J Gen Microbiol, 1986 Nov, 132 ( Pt 11), 3055 - 9 dam methylation in the archaebacteria; Lodwick D et al.; The DNA of certain species of halophilic and methanogenic archaebacteria is dam methylated, as shown by restriction endonuclease sensitivities . The Dam+ phenotype appears to be confined to particular taxonomic groupings defined by DNA:rRNA hybridization or 16S RNA oligonucleotide cataloguing. J Biol Chem, 1986 Oct 15, 261(29), 13850 - 1 Crystallographic characterization of a photoactive yellow protein with photochemistry similar to sensory rhodopsin; McRee DE et al.; A photoactive yellow protein purified from the phototrophic bacterium Ectothiorhodospira halophila, has been crystallized by vapor diffusion from ammonium sulfate solution . The hexagonal crystals are in space group P6(3) with unit cell dimensions a = b = 66.89, c = 40.68 A and appear to have one 15,000-dalton protein in the asymmetric unit . Photoactive yellow protein contains a chromophore with retinal-like properties; its color can be reversibly bleached, by visible light, with kinetics similar to those of sensory rhodopsin . The crystals can also be bleached by an intense visible light source without cracking, but are not bleached by x-rays . This suggests that structures can be obtained for both bleached and colored conformations of the protein-bound chromophore . The crystals diffract strongly to at least 1.3 A resolution, are resistant to radiation damage, and are suitable for a high resolution structure determination . The covalently bound chromophore and photobleaching characteristics of the protein offer unique opportunities to study protein conformational change and refolding as well as to understand the mechanisms of light-induced conformational change at atomic resolution. Microbiologia, 1986 Oct, 2(2), 73 - 80 Potassium ion accumulation in cells of different halobacteria; Perez-Fillol M et al.; Halobacteria live in extremely hypersaline environments accumulating K+ as compatible solute . We have studied the accumulation of intracellular potassium in recently isolated halobacteria with relatively moderate salt response, and compared it with the classical halobacteria with very extreme salt response . Significant differences have been found, the more moderate group having lower intracellular K+ concentrations . Some experiments have been carried out concerning the energy dependence of this K+ accumulation, which indicate that the moderate group seems to be less dependent on metabolic energy . The results are consistent with existence of different degrees of halophilia among halobacteria, probably corresponding to adaptation to different habitats. J Bacteriol, 1986 Oct, 168(1), 425 - 7 Immunologic distinctiveness of archaebacteria that grow in high salt; de Macario EC et al.; The antigenic fingerprints of eight halophilic archaebacteria representing the groups recently outlined by molecular and chemical analyses were determined with calibrated antibody probes . Comparison with the antigenic fingerprints of methanogens encompassing all described families and most genera demonstrated that these two archaebacterial groups are themselves antigenically coherent but immunologically distinct. J Mol Biol, 1986 Jul 5, 190(1), 97 - 106 Solution structure of halophilic malate dehydrogenase from small-angle neutron and X-ray scattering and ultracentrifugation; Zaccai G et al.; Data from small-angle X-ray and neutron scattering and ultracentrifugation experiments on solutions of malate dehydrogenase from Halobacterium maris mortui are analysed together to yield a model for the enzyme particle formed by the protein and its interactions with water and salt in the solvent . The halophilic enzyme is stable only in high concentrations of salt and the model has structural features that are absent from non-halophilic malate dehydrogenase . The complementarity of the information derived from the three experimental methods is discussed extensively and quantitatively . It derives from the fact that mass density (ultracentrifugation), electron density (X-rays) and neutron scattering density are independent of each other . Each method gives a different "view" of the same particle, and an analysis of the combined data provided thermodynamic and structural parameters with, apart from the chemical composition of the solutions, only one other assumption: a constant partial specific volume for water equal to 1.00 cm3 g-1 . Both the insights gained by this novel approach and its limitations are carefully pointed out . In solvents between 1 M and 5 M-NaCl, the enzyme forms a particle of invariant volume, consisting of a protein dimer (87,000 g mol-1) with which are associated 0.87 g of water and 0.35 g of salt per gram of protein . The partial specific volume of the protein calculated from the combined experimental data is 0.753(+/- 0.030) cm3 g-1, in good agreement with the value calculated from the amino acid composition . The particle has a radius of gyration of 32 A and an equivalent Stokes radius of 43 A . By combining the data from the X-ray and neutron scattering studies, the radii of gyration of the protein moiety alone and of the associated water and salt distribution were calculated . They are 28 A and about 40 A, respectively . The large-angle scattering curves show that the shapes of the particle and of the protein moiety alone are similar . At very low resolution they can be approximated by an ellipsoid of axial ratio 1:1:0.6 (or 1:1:1.5) . At higher resolution, it becomes apparent that the particle has a significantly larger interface with solvent than an homogeneous ellipsoid or globular protein . The model has a globular protein core similar to non-halophilic malate dehydrogenase, with about 20% of the protein extending loosely out of the core, forming the large interface with solvent . The main interactions with water and salt take place on this outer part. Biochem Cell Biol, 1986 Jul, 64(7), 675 - 80 The primary structure of the ribosomal A-protein (L12) from the moderate halophile NRCC 41227; Falkenberg P et al.; The complete amino acid sequence of the ribosomal A-protein (equivalent to L7/L12 in Escherichia coli) from a moderate halophile, NRCC 41227, has been determined using an automatic Beckman sequencer and by the manual Edman cleavage of peptides obtained from selective proteolytic cleavage of the ribosomal A-protein . The protein contains 122 amino acids and has a composition of Asp5, Asn2, Thr6, Ser6, Glu21, Gln2, Pro2, Gly12, Ala21, Val14, Met4, Ile4, Leu9, Phe2, Lys11, and Arg1, and a molecular weight of 12 537 . It has a net negative charge of -14 and is, therefore, slightly more acidic than other eubacterial ribosomal A-proteins . The phylogenetic tree, obtained by computer analysis of the amino acid sequence of this and other eubacterial A-proteins, indicate these proteins form five subgroups within the eubacterial kingdom . The moderate halophile NRCC 41227 is part of a group of Gram-negative bacteria that include E . coli and another moderate halophile Vibrio costicola . The sequence data provides further evidence that the moderate and extreme halophiles have evolved by separate pathways. J Bacteriol, 1986 Jul, 167(1), 265 - 71 Unique antibiotic sensitivity of archaebacterial polypeptide elongation factors; Londei P et al.; The antibiotic sensitivity of the archaebacterial factors catalyzing the binding of aminoacyl-tRNA to ribosomes (elongation factor Tu {EF-Tu} for eubacteria and elongation factor 1 {EF1} for eucaryotes) and the translocation of peptidyl-tRNA (elongation factor G {EF-G} for eubacteria and elongation factor 2 {EF2} for eucaryotes) was investigated by using two EF-Tu and EF1 {EF-Tu(EF1)}-targeted drugs, kirromycin and pulvomycin, and the EF-G and EF2 {EF-G(EF2)}-targeted drug fusidic acid . The interaction of the inhibitors with the target factors was monitored by using polyphenylalanine-synthesizing cell-free systems . A survey of methanogenic, halophilic, and sulfur-dependent archaebacteria showed that elongation factors of organisms belonging to the methanogenic-halophilic and sulfur-dependent branches of the "third kingdom" exhibit different antibiotic sensitivity spectra . Namely, the methanobacterial-halobacterial EF-Tu(EF1)-equivalent protein was found to be sensitive to pulvomycin but insensitive to kirromycin, whereas the methanobacterial-halobacterial EF-G(EF2)-equivalent protein was found to be sensitive to fusidic acid . By contrast, sulfur-dependent thermophiles were unaffected by all three antibiotics, with two exceptions; Thermococcus celer, whose EF-Tu(EF1)-equivalent factor was blocked by pulvomycin, and Thermoproteus tenax, whose EF-G(EF2)-equivalent factor was sensitive to fusidic acid . On the whole, the results revealed a remarkable intralineage heterogeneity of elongation factors not encountered within each of the two reference (eubacterial and eucaryotic) kingdoms. J Bacteriol, 1986 May, 166(2), 686 - 8 Polyadenylated RNA isolated from the archaebacterium Halobacterium halobium; Brown JW et al.; Polyadenylated {poly(A)+} RNA has been isolated from the halophilic archaebacterium Halobacterium halobium by binding, at 4 degrees C, to oligo(dT)-cellulose . H . halobium contains approximately 12 times more poly(A) per unit of RNA than does the methanogenic archaebacterium Methanococcus vannielii . The 3' poly(A) tracts in poly(A)+ RNA molecules are approximately twice as long (average length of 20 nucleotides) in H . halobium as in M . vannielii . In both archaebacterial species, poly(A)+ RNAs are unstable. Nucleic Acids Res, 1986 Mar 25, 14(6), 2459 - 79 Transcription signals for stable RNA genes in Methanococcus; Wich G et al.; A previous survey of upstream sequences of tRNA genes from the archaebacterium Methanococcus vannielii has revealed that there are two boxes of sequence homology: A box "A" of about 20 conserved nucleotides at a distance of 30 to 49 basepairs upstream from the gene and a box "B" 18 to 19 nucleotides downstream from box "A" (Wich, G., Sibold, L., and Bock, A . (1985) System . Appl . Microbiol . (in press) . Nuclease S1 mapping experiments were carried out with two of these tRNA transcriptional units and with a ribosomal RNA operon, to determine whether these consensus sequences have a function in the initiation of transcription . Use was made of the fact that cells from Methanococcus accumulate primary transcript and processing intermediates of ribosomal RNA under conditions of protein synthesis inhibition . The following results were obtained: (i) Transcription in all three systems starts at the G within the conserved trinucleotide TGC of box "B" . Since the box "B" motif, 5'TGCaagT3', also occurs at the site of transcription initiation of protein encoding genes, both in methanogenic and halophilic organisms, it appears to constitute a frequently used transcription start signal within these archaebacterial groups . (ii) The box "A" motif occurs with constant spacing, relative to box "B", in all 10 tRNA and ribosomal RNA transcriptional units investigated from Methanococcus . Since it is not present in the leader region of genes coding for proteins, it seems to function as a specific element which is required for the expression of genes for stable RNA . (iii) Termination of transcription of the ribosomal RNA operon from Methanococcus occurs at a distinct T within an oligo-T stretch immediately downstream from the 3'-terminal 5S RNA gene . This signal occurs in all 3'-flanking regions of transcriptional units for stable RNA from the Methanococcus strains studied . Termination signals for stable RNA genes in Methanococcus appear to be similar with those of stable RNA genes in eukaryotes . (iv) By nuclease S1 mapping a recognition site was identified for a processing enzyme involved in the maturation of preribosomal RNA. J Biol Chem, 1986 Feb 25, 261(6), 2616 - 22 Generation of Na+ electrochemical potential by the Na+-motive NADH oxidase and Na+/H+ antiport system of a moderately halophilic Vibrio costicola; Udagawa T et al.; Cells of Vibrio costicola at pH 8.5 generate both membrane potential (inside negative) and delta pH (inside acidic) in the presence of a proton conductor, carbonyl cyanide m-chlorophenylhydrazone (CCCP) . The generation of CCCP-resistant membrane potential was inhibited by 2-heptyl-4-hydroxyquinoline-N-oxide that is known to inhibit the Na+-motive NADH oxidase of Vibrio alginolyticus . NADH oxidase, but not lactate oxidase, of inverted membrane vesicles prepared from V . costicola required Na+ for a maximum activity and was inhibited by 2-heptyl-4-hydroxyquinoline-N-oxide . By the oxidation of NADH, inverted membrane vesicles generated concentration gradients of Na+ across the membrane, whose magnitude was always larger than that of delta pH by about 50 mV . In contrast, magnitudes of delta pH and Na+ concentration gradients generated by the oxidation of lactate were similar . Na+ translocation in the presence of lactate was inhibited by CCCP but little affected by valinomycin . On the other hand, Na+ translocation in the presence of NADH was resistant to CCCP and stimulated by valinomycin . Amiloride, an inhibitor for a eucaryotic Na+/H+ antiport system, inhibited the lactate-dependent Na+ translocation but had little effect on the NADH-dependent Na+ translocation . These results indicate that a primary event of lactate oxidation is the translocation of H+, which then causes the generation of Na+ concentration gradients via the secondary Na+/H+ antiport system . We conclude that the NADH oxidase of V . costicola translocates Na+ as an immediate result of respiration, leading to the generation of Na+ electrochemical potential. Biochemistry, 1986 Jan 14, 25(1), 60 - 7 Hydrogen-1 nuclear magnetic resonance investigation of high-potential iron-sulfur proteins from Ectothiorhodospira halophila and Ectothiorhodospira vacuolata: a comparative study of hyperfine-shifted resonances; Krishnamoorthi R et al.; Proton NMR spectra of the oxidized and reduced forms of high-potential iron-sulfur proteins (HiPIPs) were recorded at 200 MHz . The proteins studied were the HiPIPs I and II from Ectothiorhodospira halophila and Ectothiorhodospira vacuolata . Hyperfine-shifted peaks in spectra of the oxidized proteins were assigned to some of the protons of the cysteinyl ligands and aromatic residues at the active site on the basis of their chemical shifts, longitudinal relaxation times, and temperature-dependent behavior . The cysteinyl C beta-H protons were found to resonate downfield (about 100 ppm) and the C alpha-H protons upfield (about-25 ppm) . This hyperfine shift pattern is consistent with the observed isotropic shift being contact in origin; it probably results from a pi-spin-transfer mechanism . The large magnitudes of the chemical shifts of peaks assigned to aromatic residues suggest that these residues interact with the iron-sulfur cluster via pi-pi overlap . Some of the hyperfine-shifted peaks observed in water were found to disappear in 2H2O solution . Such resonances probably arise from exchange-labile hydrogens of amino acid residues directly hydrogen bonded to the iron-sulfur cluster . In the case of HiPIPs I and II from E . vacuolata, whose spectra are similar except for the number of such peaks, the relative number of hydrogen bonds inferred to be present in the oxidized and reduced proteins qualitatively explains the difference between their midpoint redox potentials . On the other hand, for E . halophila HiPIPs I and II, consideration of the inferred number of hydrogen bonds alone fails to predict the sign of the difference between their midpoint redox potentials.(ABSTRACT TRUNCATED AT 250 WORDS) Bull Soc Pathol Exot Filiales, 1986, 79(2), 247 - 50 {The small halophilic zygopteric odonate, Mortonagrion hirosei, of central Japan, a predator utilizable against tiny stinging diptera of coastal salt marshes, especially Ceratopogonidae of the genera Culicoides and Oecacta, pests of sea shores in southwestern U.S.A . and Caribbean area}; Vasserot J; Among stinging diptera pullulating in coastal salt marshes Ceratopogonidae gnats (mainly of genus Culicoides and Oecacta) are especially troublesome, particularly in Southeastern U . S . A . and Caribbean area, escaping attacks of most predators by their tiny size . But the zygopteric odonate insect Mortonagrion hirosei is well fitted for hunting those minute diptera, by its tiny size and its behaviour, seeking shelter between halophilic plants (2 facts explaining that it was not discovered in central Japan before 1971...) . Its larvae, living in brackish waters of coastal lagoons, can devour those of Ceratopogonidae and at least young stages of those of Mosquitoes whose some halophilic species are dangerous vectors of diseases . According to similarity of climates M . hirosei can certainly thrive in Southeastern U . S . A., and probably in Southern Europe . At lower latitudes problems for completion of annual cycle could perhaps arise from lack of hivernal cooling . It is necessary to make at the world scale methodical researches for other species of zygopteric odonates of similar ecology which could exist in other countries, both for avoiding harmful competition of introduced M . hirosei with native species still unknown and for fulfilling the same ecological function in areas of climate no suitable for this Japanese insect . Introduction of M . hirosei in new geographic areas would be very useful, too, for protection of this interesting species threatened by human activities in its natural biotopes, made of discontinuous and rather little areas. Biochimie, 1986 Jan, 68(1), 75 - 84 Redox properties and activity studies on a nickel-containing hydrogenase isolated from a halophilic sulfate reducer Desulfovibrio salexigens; Teixeira M et al.; A soluble hydrogenase from the halophilic sulfate reducing bacterium Desulfovibrio salexigens, strain British Guiana (NCIB 8403) has been purified to apparent homogeneity with a final specific activity of 760 mumoles H2 evolved/min/mg (an overall 180-fold purification with 20% recovery yield) . The enzyme is composed of two non-identical subunits of molecular masses 62 and 36 kDa, respectively, and contains approximately 1 Ni, 12-15 Fe and 1 Se atoms/mole . The hydrogenase shows a visible absorption spectrum typical of an iron-sulfur containing protein (A400/A280 = 0.275) and a molar absorbance of 54 mM-1cm-1 at 400 nm . In the native state (as isolated, under aerobic conditions), the enzyme is almost EPR silent at 100 K and below . However, upon reduction under H2 atmosphere a rhombic EPR signal develops at g-values 2.22, 2.16 and around 2.0, which is optimally detected at 40 K . This EPR signal is reminiscent of the nickel signal C (g-values 2.19, 2.16 and 2.02) observed in intermediate redox states of the well characterized D . gigas nickel containing hydrogenase and assigned to nickel by 61 Ni isotopic substitution (J.J.G . Moura, M . Teixeira, I . Moura, A.V . Xavier and J . Le Gall (1984), J . Mol . Cat., 23, 305-314) . Upon longer incubation with H2 the "2.22" EPR signal decreases . During the course of a redox titration under H2, this EPR signal attains a maximal intensity around--380 mV . At redox states where this "2.22" signal develops (or at lower redox potentials), low temperature studies (below 10 K) reveals the presence of other EPR species with g-values at 2.23, 2.21, 2.14 with broad components at higher fields . This new signal (fast relaxing) exhibits a different microwave power dependence from that of the "2.22" signal, which readily saturates with microwave power (slow relaxing) . Also at low temperature (8 K) typical reduced iron-sulfur EPR signals are concomitantly observed with gmed approximately 1.94 . The catalytic properties of the enzyme were also followed by substrate isotopic exchange D2/H+ and H2 production measurements. J Clin Microbiol, 1986 Jan, 23(1), 104 - 8 Vibrio cincinnatiensis sp . nov., a new human pathogen; Brayton PR et al.; A halophilic gram-negative rod was isolated from blood and cerebrospinal fluid collected from a 70-year-old male having no known contact with seafood or salt water . Positive biochemical tests included oxidase, sensitivity to 0/129, O-nitrophenyl-beta-D-galactopyranoside, lysine decarboxylase and fermentation of glucose, salicin, n-inositol, sucrose, L-mannose, L-arabinose, and arbutin . Negative tests included indole, ornithine decarboxylase, arginine dihydrolase fermentation of lactose, and production of gelatinase and urease . The DNA base composition was 45.0 mol% guanine plus cytosine . Numerical taxonomy indicated 70% similarity with known reference Vibrio sp . strains . The 5S rRNA sequence for this strain has been determined: 5'-U G C C U G G C G A C C A U A G C G U U U U G G A C C C A C C U G A U U C C A U G C C G A A C U C A G U A G U G A A A C G A A A C A G C G U C G A U G G U A G U G U G G G G U C U C C C C A U G U G A G A G U A G A A C A U C G C C A G G C A U-3' . Based on the phenetic, molecular genetic, and nucleic acid sequencing data, it is concluded that Vibrio cincinnatiensis represents a new species of the genus Vibrio sensu strictu (as defined by 5S rRNA sequencing results) . On a basis of 5S rRNA comparative sequence analysis, the organism appears to share a recent common ancestor with V . gazogenes (98% homology) and close ancestry with V . mimicus, V . fluvialis, and V . metschnikovii. Arch Biochem Biophys, 1985 Nov 15, 243(1), 238 - 45 Regulation of respiration by Na+ and K+ in the halotolerant bacterium, Ba1; Ken-Dror S et al.; In the obligate aerobe, moderate halophile bacterium, Ba1, the ion composition of the medium was found to have a profound influence on the response of the respiratory system to changes in the external pH . In the pH range 6.5 to 8.5 the respiratory activity either increased or decreased progressively, depending whether K+ or Na+ ions were omitted from the medium . A nearly constant rate of respiration was observed in the entire pH range when both K+ and Na+ were present simultaneously . The stimulatory effect of Na+ was expressed especially in the alkaline pH range, where it induced acidification of the intracellular milieu . It was manifest in whole cells as well as in inverted membrane vesicles, and was not affected by either uncoupler or inhibitor of H+-ATPase . In contrast, the respiratory stimulation induced by K+ was most prominent in the acidic pH range and was accompanied by alkalinization of the internal pH . The effect of K+ was observed only in intact cells . Agents which interfered with energy transfer suppressed the effect of K+ . With ethanol as the electron donor, Na+ was found to decrease the extent of reduction of the cellular NAD+ in the aerobic steady state, and to cause increased reduction of the cytochromes . K+ had no appreciable effect on the extent of reduction of any component in the respiratory chain . The implications of the above findings are discussed in relation to the mechanism(s) involved in the cation-mediated regulation of respiration and intracellular pH. Microbiol Sci, 1985 Nov, 2(11), 345 - 50 Haloadaptation: salt sensing and cell-envelope changes; Russell NJ et al.; When moderately halophilic bacteria adapt phenotypically to altered salinity, they modify the composition of their cell envelopes . These alterations are discussed in the context of how external salt concentration could be sensed and the adaptive changes triggered . A general model for salt sensing and signal transduction is suggested. Can J Microbiol, 1985 Sep, 31(9), 870 - 2 Growth of Vibrio costicola and other moderate halophiles in a chemically defined minimal medium; Kamekura M et al.; A simple chemically defined minimal medium consisting of sodium glutamate, glucose, vitamins, and salts was devised to support growth of the moderate halophile, Vibrio costicola, over as wide a range of NaCl concentrations as the complex medium, proteose peptone + tryptone . The lag period at higher NaCl concentrations was longer in the chemically defined minimal medium than in proteose peptone + tryptone . Chemically defined minimal medium also supported the growth of an unidentified moderate halophile, HX, and of Vibrio alginolyticus and Vibrio cholerae . The Mg2+ concentration required for good growth changed with the growth temperature for both V . costicola and HX. Arch Biochem Biophys, 1985 Sep, 241(2), 656 - 64 Amino acid sequence of high-redox-potential ferredoxin (HiPIP) isozymes from the extremely halophilic purple phototrophic bacterium, Ectothiorhodospira halophila; Tedro SM et al.; The amino acid sequences of high-redox-potential ferredoxin (HiPIP) isozymes from Ectothiorhodospira halophila have been determined . These are: isozyme I, EPRAEDGHAHDYVNEAADPSHGRYQEGQLCENCAFWGEAVQDGWGRCTHPDFDEVLVKAEGWCSVYAPA S, and isozyme II, GLPDGVEDLPKAEDDHAHDYVNDAADTDHARFQEGQLCENCQFWVDYVNGWGYCQHPDFTDVLVRGEGW CSVYAPA . Isozyme II is the major form of HiPIP produced by the bacterium (65-80%) and is the most acidic of the known HiPIPs . The two isozymes are 72% identical to one another and require only a single residue deletion for alignment . Comparison of these HiPIPs with seven previously determined sequences revealed only 27% average identity . Both E . halophila HiPIP isozymes are likely to be functional since their sequences are equally distant from those of other species . The E . halophila HiPIP sequences show that H-bonding patterns recognized in Chromatium vinosum HiPIP are likely to be conserved and therefore cannot explain the unusually low redox potentials which have been reported. Microbiologia, 1985 Sep, 1(1-2), 29 - 33 Isolation of methanogenic bacteria able to grow in high salt concentration; Perez-Fillol M et al.; A new obligate halophilic methane-producing bacterium has been isolated from the sediment of solar salt ponds . This isolate was unable to grow at or below 12% salt concentration and used H2/CO2 (80/20) as energy and carbon source . No growth or methanogenesis was observed with other reduced substrates . This is, to our knowledge, the first obligately halophilic methanogenic bacteria described . Since the phylogenetic nexus between methanogenic and halobacteria seem to be relatively close, the study of this organism could help to understand the relations between these two groups of archaebacteria. Microbiologia, 1985 Sep, 1(1-2), 89 - 96 Isolation and characterization of moderately halophilic nonmotile rods from different saline habitats; Quesada E et al.; A total of 736 strains were isolated from samples taken from three different saline habitats: solar saltern, saline soils and the sea, near Alicante (Spain) . For a further study 60 moderately halophilic nonmotile rods were selected and studied for 57 phenotypic characteristics . The highest proportion of moderately halophilic nonmotile rods were isolated from saline soils and in media with 10 or 20% salts, being very scarce in sea water samples . All were Gram-negative rods and were included in two groups: 33 oxidase positive strains could be assigned to the genus Flavobacterium and 24 oxidase negative strains to the genus Acinetobacter. Am J Gastroenterol, 1985 Sep, 80(9), 706 - 8 Spontaneous Vibrio vulnificus peritonitis and primary sepsis in two patients with alcoholic cirrhosis; Wongpaitoon V et al.; Two patients with alcoholic cirrhosis were seen on two separate occasions for fever, swollen legs, petechial hemorrhage, purpura, and cutaneous bullae . One patient ate oysters 2 days before the onset of illness . Vibrio vulnificus, a lactose-positive halophilic vibrio, was isolated from the ascitic and cutaneous fluid in both cases, and from the blood in one of the two cases . Both isolated strains were sensitive to the antibiotics given to the patients from the beginning; however, both patients died, one from septicemic shock and the other from massive esophageal variceal hemorrhage . Autopsies in both patients revealed alcoholic cirrhosis, hemorrhagic necrosis of the terminal ileum, intraalveolar hemorrhage, petechial hemorrhage in the peritoneum, and nonspecific acute inflammation of the dermis with vasculitis . Physicians should consider V . vulnificus in the differential diagnosis of cirrhotic patients with sepsis, primary skin lesions, and spontaneous bacterial peritonitis with or without history of recent oyster ingestion. Biochim Biophys Acta, 1985 Jul 17, 808(2), 213 - 8 Complexity in the redox titration of the dihaem cytochrome c4; Leitch FA et al.; Redox titration of the dihaem, two domain cytochromes c4 from Pseudomonas aeruginosa, Pseudomonas stutzeri and Azotobacter vinelandii showed complex behaviour indicative of the presence of two redox components . In the case of the P . stutzeri cytochrome c4, two spectroscopically distinct components were present during the redox titration . In contrast, cytochrome c-554(548) from a halophilic Paracoccus species is a stable dimer of a monohaem cytochrome which shows close homology to cytochrome c4, but does not show complexity in its redox titration . The presence of chemically distinct haem environments or anti-cooperative interactions between identical haem groups are two possible explanations for the redox complexity of cytochrome c4 . The simple redox titration of cytochrome c-554(548) shows that haems situated relatively close together need not interact, but direct cleavage, separation and study of the domains will be necessary to decide whether they do or do not interact in the case of cytochrome c4. J Microsc, 1985 Jul, 139 ( Pt 1), 63 - 74 The structure of the stalk surface layer of a brine pond microorganism: correlation averaging applied to a double layered lattice structure; Kessel M et al.; The surface layer of the stalk of a prosthecate halophilic microorganism is a periodic array (space group p3m1) comprised of electron dense trimers with a centre to centre spacing of 9.0 nm . The structure is reminiscent of E . coli porin . We have demonstrated that the method of correlation averaging can be effectively used to separate overlapping lattices, and that this results in a higher fidelity reconstruction, when compared to the established method of Fourier filtration . Two statistical methods are used to determine the resolution of the correlation average as a function of the number of 'windows' averaged . (i) The phase residual of spatial frequencies in Fourier space is computed between independently obtained subaverages, and (ii) a new method of Q factor analysis examines the cumulative vector sum in Fourier space as a function of the number of windows averaged . Both methods give a resolution of 1/2.1 nm-1. Surgery, 1985 Jul, 98(1), 126 - 30 Necrotizing soft-tissue infections caused by marine vibrios; Howard RJ et al.; Halophilic, noncholera marine Vibrio bacteria can cause septicemia, gastroenteritis, cellulitis, and necrotizing fasciitis . We describe six patients with necrotizing fasciitis and review 12 cases described previously . The 18 patients included 14 men and four women . Their ages ranged from 32 to 79 years (average 58.1 years) . Eleven patients were older than 55 years . Nine infections were caused by V . vulnificus, three by V . parahaemolyticus, and one by V . alginolyticus . In five cases the Vibrio species was not identified . Twelve patients had associated conditions that might have made them more susceptible to these infections, such as cirrhosis, steroid therapy, hemochromatosis, and multiple myeloma . These infections usually occur in apparently insignificant wounds (puncture wounds, insect bites) exposed to sea water or fish . Treatment is by debridement and antibiotic therapy . Three patients required amputation to control the infection . Six (33.3%) of the 18 patients died. Infect Immun, 1985 Jul, 49(1), 25 - 31 Purification and characterization of an extracellular cytolysin produced by Vibrio damsela; Kothary MH et al.; Large amounts of an extremely potent extracellular cytolysin produced by the halophilic bacterium Vibrio damsela were obtained free of detectable contamination with medium constituents and other bacterial products by sequential ammonium sulfate precipitation, gel filtration with Sephadex G-100, and hydrophobic interaction chromatography with phenyl-Sepharose CL-4B . The cytolysin is heat labile and protease sensitive and has a molecular weight (estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis) of ca . 69,000 and an isoelectric point of ca . 5.6 . The first 10 amino-terminal amino acid residues of the cytolysin are Phe-Thr-Gln-Trp-Gly-Gly-Ser-Gly-Leu-Thr . The cytolysin was very active against erythrocytes from 4 of the 18 animal species examined (mice, rats, rabbits, damselfish) and against Chinese hamster ovary cells and was lethal for mice (ca . 1 microgram/kg, intraperitoneal median lethal dose) . Lysis of mouse erythrocytes by the cytolysin is a multi-hit, at least two-step process consisting of a temperature-independent, toxin-binding step followed by a temperature-dependent, membrane-perturbation step(s). J Biochem (Tokyo), 1985 Jun, 97(6), 1653 - 8 Polyamines in photosynthetic eubacteria and extreme-halophilic archaebacteria; Hamana K et al.; Qualitative and quantitative determinations of polyamines have been done in 4 photosynthetic eubacteria and 6 extreme-halophilic archaebacteria . For comparison, 5 moderate-halophilic eubacteria were also analyzed to determine their polyamine contents . Not only putrescine and spermidine but also homospermidine were found in the photosynthetic eubacteria, especially in the N2-fixing species, Rhodospirillum and Chromatium . Norspermidine, norspermine, and spermine were not detected in the phototrophic eubacteria . No appreciable amount of any polyamine was found in extreme-halophilic archaebacteria, Halobacterium and Halococcus, while moderate-halophilic eubacteria contained quite high concentrations of putrescine and spermidine and cadaverine . When arginine was incubated with cell lysates of these two archaebacteria, appreciable amounts of agmatine were produced; neither putrescine nor cadaverine was formed in the presence of ornithine or lysine . No detectable amount of spermidine was produced by the lysates on incubation with putrescine. Can J Microbiol, 1985 Jun, 31(6), 543 - 8 Membrane-bound 5'-nucleotidase in marine luminous bacteria: biochemical and immunological properties; Bengis-Garber C; A novel 5'-nucleotidase previously described in halophilic Vibrio costicola was detected in marine Vibrio and Photobacterium strains . The enzyme of marine bacteria was similar in its properties to the 5'-nucleotidase of Vibrio costicola; it was outwardly oriented in the cytoplasmic membrane and dephosphorylated nucleoside 5'-tri-, di-, and mono-phosphates to respective nucleosides before uptake . The enzyme in marine strains was immunologically cross-reactive with the antibody raised against the purified 5'-nucleotidase of Vibrio costicola . The uptake of the products of ATP hydrolysis was studied in Vibrio harveyi, and it was shown that both adenosine and inorganic phosphate released upon the action of 5'-nucleotidase were rapidly taken up by the cell. Arch Biochem Biophys, 1985 May 15, 239(1), 200 - 5 Soluble succinate dehydrogenase from the halophilic archaebacterium, Halobacterium halobium; Gradin CH et al.; Succinate dehydrogenase activity was found in both the cytoplasmic and the membrane fractions from disrupted Halobacterium halobium cells . The cytoplasmic enzyme was found to be soluble in aqueous media and had an apparent molecular weight of 90,000 . The enzyme activity of the cytoplasmic succinate dehydrogenase was salt dependent, with preference for KCl over KNO3 . The Km values for succinate of the soluble and the membrane-bound succinate dehydrogenases from H . halobium were 2.3 +/- 0.3 and 0.7 +/- 0.1 mM, respectively . The soluble succinate dehydrogenase was obtained from two different strains of H . halobium and was obtained independently of the method used to disrupt the bacteria . Thus, the archaebacterium, H . halobium, contains a succinate dehydrogenase which differs from the succinate dehydrogenase in most eucaryotic and eubacterial cells, where the enzyme is tightly membrane-bound. Eur J Biochem, 1985 May 15, 149(1), 135 - 9 1,4,5,6-Tetrahydro-2-methyl-4-pyrimidinecarboxylic acid . A novel cyclic amino acid from halophilic phototrophic bacteria of the genus Ectothiorhodospira; Galinski EA et al.; A novel cyclic amino acid was detected in and subsequently isolated from extremely halophilic species of the bacterial genus Ectothiorhodospira . The structure of this new compound was elucidated by a combination of nuclear magnetic resonance (NMR) techniques and mass spectrometry . 1,4,5,6-Tetrahydro-2-methyl-4-pyrimidinecarboxylic acid is only accumulated within the cytoplasm under certain growth conditions and seems to serve an osmoregulatory function . There is no previous reference to this molecule in the chemical literature and we, therefore, propose to use the trivial name 'ectoine', due to its discovery in members of the bacterial genus Ectothiorhodospira . (formula: see text). Biochemistry, 1985 May 7, 24(10), 2542 - 9 Circular dichroism and redox properties of high redox potential ferredoxins; Przysiecki CT et al.; The circular dichroism (CD) spectra of 13 examples of high-potential iron-sulfur proteins (HiPIPs), a class of {4Fe-4S} ferredoxins, have been determined . In contrast to the proposal of Carter {Carter, C . W., Jr . (1977) J . Biol . Chem . 252, 7802-7811}, no strict correlation between visible CD features and utilization of the {4Fe-4S}2+/{4Fe-4S}3+ oxidation levels was found . Although most HiPIPs have these features, the model requires their presence in all species . There is also no simple relationship between CD spectral features and the presence of conserved tyrosine-19 . In addition, no apparent correlation between CD properties and oxidation-reduction potential could be detected . However, amino acid side chains in close contact to the iron-sulfur cluster appear to be important in modulating spectral and oxidation-reduction properties . In particular, the negative shoulder at 290 nm and negative maximum at 230 nm correlate with the presence of Trp-80 (Chromatium vinosum numbering) . Two HiPIPs that do not have Trp at this position have positive bands at 290 and 230 nm . These bands in the Ectothiorhodospira halophila HiPIPs are apparently associated with Trp-49, which is located on the opposite side of the effective mirror plane of the cluster from Trp-80 . The effect of pH on circular dichroism and redox potential in Thiocapsa roseopersicina HiPIP, which has a histidine at position 49, is consistent with the interaction of the side chain with the cluster . Despite specific differences in their CD spectra, the various HiPIPs studied show general similarity consistent with structural homology within this class of iron-sulfur proteins. Biochem J, 1985 May 1, 227(3), 1009 - 13 The amino acid sequence of the cytochrome c-554(547) from the chemolithotrophic bacterium Thiobacillus neapolitanus; Ambler RP et al.; An amino acid sequence is proposed for the cytochrome c-554(547) from the bacterium Thiobacillus neapolitanus N.C.I.B . 8539) . It consists of a polypeptide chain of 91 residues, with a pair of haem-attachment cysteine residues at positions 15 and 18 . There is similarity in sequence with each of the halves of the sequence of the dihaem cytochromes c4 and with a cytochrome c-554(548) from a halophilic strain of Paracoccus . Detailed evidence for the amino acid sequence of the protein has been deposited as Supplementary Publication SUP 50127 (11 pages) at the British Library (Lending Division), Boston Spa, Wetherby, West Yorkshire LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem . J . (1985) 225, 5. J Bacteriol, 1985 Apr, 162(1), 461 - 2 Genetic transfer in Halobacterium volcanii; Mevarech M et al.; Auxotrophic mutants of Halobacterium volcanii generated by chemical mutagenesis were used to demonstrate a native genetic transfer system in this extremely halophilic member of the class Archaeobacteria. Infect Immun, 1985 Apr, 48(1), 62 - 72 Purification and characterization of an extracellular cytolysin produced by Vibrio vulnificus; Gray LD et al.; An extracellular cytolytic toxin produced by the halophilic bacterium Vibrio vulnificus was isolated free of detectable contamination with medium constituents and other bacterial products by sequential ammonium sulfate precipitation, gel filtration with Sephadex G-75, hydrophobic interaction chromatography with phenyl-Sepharose CL-4B, and isoelectric focusing in an ethylene glycol density gradient . The cytolysin is a heat-labile, hydrophobic protein that is inhibited by large amounts of cholesterol, is partially inactivated by proteases and trypan blue, has a molecular weight (estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and by amino acid analysis) of ca . 56,000, and has an isoelectric point of ca . 7.1 . The first 10 amino-terminal amino acid residues of the cytolysin are Gln-Glu-Tyr-Val-Pro-Ile-Val-Glu-Lys-Pro . Lysis of mouse erythrocytes by the purified cytolysin is a multi-hit, at least two-step process consisting of a temperature-independent, toxin-binding step, followed by a temperature-dependent, membrane-perturbation step(s) . In addition to possessing cytolytic activity against erythrocytes from 17 animal species and against Chinese hamster ovary cells in tissue culture, the purified cytolysin preparation was lethal for mice (ca . 3 micrograms/kg, intravenous 50% lethal dose) and had vascular permeability factor activity in guinea pig skin. Biochim Biophys Acta, 1985 Mar 22, 828(1), 29 - 38 Preparation and properties of highly-purified Vibrio costicola polynucleotide phosphorylase; Harry K et al.; Vibrio costicola polynucleotide phosphorylase (polyribonucleotide: orthophosphate nucleotidyltransferase, EC 2.7.7.8) has been purified to electrophoretic homogeneity . It has an approximate molecular weight of 220 000 and consists of identical subunits with an approximate molecular weight of 72 000 . The enzyme appears to be a fairly typical polynucleotide phosphorylase with respect to its pH optima, substrate specificity and requirement for a divalent cation cofactor . However, the effect of salt concentration on its physiologically important phosphorolysis activity suggests that it is a moderately halophilic enzyme, able to function at the intracellular ionic strength of the bacterium . In addition, its ADP polymerization activity is remarkably stimulated by polylysine. Appl Environ Microbiol, 1985 Mar, 49(3), 664 - 6 Isolation and characterization of Pediococcus halophilus from salted anchovies (Engraulis anchoita); Villar M et al.; The presence of bacteria in salted anchovies during and at the end of the curing process was investigated . Attempts to isolate bacteria under aerobic or anaerobic conditions led to the isolation of only bacteria of the genus Pediococcus which were identified as Pediococcus halophilus . The isolates correspond to a rather heterogeneous group in which some of the members differ in some biochemical tests from the types described in the literature. EMBO J, 1985 Mar, 4(3), 811 - 6 Insensitivity of archaebacterial ribosomes to protein synthesis inhibitors . Evolutionary implications; Cammarano P et al.; The effect on Sulfolobus solfataricus (an extremely thermoacidophilic archaebacterium) of selected inhibitors affecting reactions of the polypeptide elongation cycle has been tested by using poly(U) and poly(UG) directed cell-free systems . The results reveal a unique pattern of antibiotic sensitivity of Sulfolobus ribosomes with an inhibitory effect observed for only three of 60 compounds tested . Through comparison with suitable eubacterial and eukaryotic cell-free systems the insensitivity of Sulfolobus ribosomes to most inhibitors of protein synthesis appears to reflect a phylogenetic distinction of ribosome structure, rather than the high temperature conditions of the Sulfolobus assay system . In this respect ribosomes of thermoacidophilic archaebacteria differ not only from their eubacterial and eukaryotic counterparts, but also from ribosomes of archaebacteria belonging to the methanogenic-halophilic branch of the 'third' kingdom . The evolutionary implications of these findings are discussed. Biochim Biophys Acta, 1985 Feb 28, 813(1), 111 - 6 Fluorescence energy transfer between ionophore, A23187, and membrane proteins of isolated outer and cytoplasmic membranes of a Gram-negative bacterium; Hyono A et al.; When tryptophan residues of the proteins of outer and cytoplasmic membranes of a moderately halophilic bacterium, Pseudomonas halosaccharolytica ATCC 29423, were excited at the wavelength 270 nm, tryptophan emission was observed at 330 nm . Adding the calcium ionophore, A23187, to both suspensions, the tryptophan emission at 330 nm decreased and the ionophore emission at 430 nm increased . Thus, when the calcium ionophore was increased in both suspensions, the ionophore emission increased with excitation of membrane tryptophan, that is, the fluorescence energy was transferred from tryptophan to the calcium ionophore . Using the Forster equation the critical distance was calculated to be 52 A . As this distance is considerable compared with the diameter of the membrane protein molecules, the ionophore cannot be bound to the membrane proteins . It is probably located in the lipid bilayers. J Bacteriol, 1985 Feb, 161(2), 681 - 6 Proton circulation in Vibrio costicola; Hamaide F et al.; The importance of proton movements was assessed in the moderate halophile Vibrio costicola . When anaerobic cells in acidic buffer (pH 6.5) were given an O2 pulse, protons were extruded regardless of the presence of Na+ . At pH 8.5, however, V . costicola produced an acidic response to an O2 pulse in the absence of Na+ and an alkaline response when Na+ was present . An Na+/H+ antiport activity was confirmed at pH 8.5 . All of these effects were prevented by protonophores or butanol treatment . Growth in complex medium at pH 8.5 was prevented by a high concentration (50 microM) of carbonyl cyanide m-chlorophenyl-hydrazone (CCCP) or a low concentration (5 microM) of another protonophore, 3,3',4',5-tetrachlorosalicylanilide (TCS) . The relative ineffectiveness of the former protonophore was caused by the proteose peptone and tryptone ingredients of the complex medium, since 5 microM completely prevented growth in their absence . The results are explained by a primary respiratory-linked proton efflux coupled to a secondary Na+/H+ antiport operating at alkaline pH . Evidence was seen for a role of Na+ in stimulating proton influx at alkaline pH, presumably via the pH homeostasis mechanism. Biochim Biophys Acta, 1985 Jan 23, 806(1), 175 - 83 Isolation and characterization of soluble cytochromes, ferredoxins and other chromophoric proteins from the halophilic phototrophic bacterium Ectothiorhodospira halophila; Meyer TE; A cytochrome c-551 and a pair of 'high redox-potential' ferredoxins (iso-high-potential iron-sulfur proteins) were found to be the major soluble electron-transport proteins in Ectothiorhodospira halophila . Smaller amounts of 'bacterial' ferredoxin and cytochrome c' were also observed . With the exception of cytochrome c-551, these proteins are commonly encountered in the purple sulfur bacteria, family Chromatiaceae and less frequently in the purple bacteria, family Rhodospirillaceae . In addition to the cytochromes and ferredoxins, E . halophila synthesizes substantial amounts of a small yellow-colored protein, which has a chromophore spectrally similar to flavins having oxygen, nitrogen or sulfur substituents in place of the 8-methyl group such as roseoflavin and the methanogen cofactor F-420 . A purple-colored protein was only partially purified, but it is spectrally similar to iron proteins having a tyrosine ligand, such as transferrin, catechuate dioxygenase, and especially the purple acid phosphatases . Neither the yellow protein nor the purple one has previously been observed in phototrophic bacteria, but may in some way be required for survival in extremely halophilic habitats . The only feature common to halophiles including E . halophila is the very acidic nature of their proteins. Zentralbl Mikrobiol, 1985, 140(2), 149 - 54 Salinity-loving fungi in Egyptian soils . II . Preliminary notes on antibiotics from halophilic Penicillium spp; Radwan SS et al.; Two halophilic Penicillium spp., isolated from saline soils, were selected for the present study . Their growth was best with 10% NaCl (w/v) in the nutrient media, but no antibiotics were produced unless relatively high proportions of potassium salts were also available . Conditions for the economic antibiotic production without achieving sterilization are specified . An economic biphasic process of fermentation in replacement culture for the production of antibiotics by halophilic Penicillium species is described. J Mol Evol, 1985, 22(4), 301 - 7 Sequence of the 16S rRNA gene from the thermoacidophilic archaebacterium Sulfolobus solfataricus and its evolutionary implications; Olsen GJ et al.; The sequence of the small-subunit rRNA from the thermoacidophilic archaebacterium Sulfolobus solfataricus has been determined and compared with its counterparts from halophilic and methanogenic archaebacteria, eukaryotes, and eubacteria . The S . solfataricus sequence is specifically related to those of the other archaebacteria, to the exclusion of the eukaryotic and eubacterial sequences, when examined either by evolutionary distance matrix analyses or by the criterion of minimum change (maximum parsimony) . The archaebacterial 16S rRNA sequences all conform to a common secondary structure, with the S . solfataricus structure containing a higher proportion of canonical base pairs and fewer helical irregularities than the rRNAs from the mesophilic archaebacteria . S . solfataricus is unusual in that its 16S rRNA-23S rRNA intergenic spacer lacks a tRNA gene. C R Acad Sci III, 1985, 300(5), 177 - 80 {Existence of sequences homologous to the V-MYB oncogene in the genome of archaebacteria}; Perbal B et al.; The presence of DNA sequences homologous to the v-myb oncogene in the genome of both halophilic and methanogenic archaebacteria was revealed after hybridization of restriction fragments with cloned probes . No myb-related sequences were detected in the DNA from S . acidocaldarius. Mol Gen Genet, 1985, 200(1), 47 - 59 Structure of genes and an insertion element in the methane producing archaebacterium Methanobrevibacter smithii; Hamilton PT et al.; DNA fragments cloned from the methanogenic archaebacterium Methanobrevibacter smithii which complement mutations in the purE and proC genes of E . coli have been sequenced . Sequence analyses, transposon mutagenesis and expression in E . coli minicells indicate that purE and proC complementations result from the synthesis of M . smithii polypeptides with molecular weights of 36,697 and 27,836 respectively . The encoding genes appear to be located in operons . The M . smithii genome contains 69% A/T basepairs (bp) which is reflected in unusual codon usages and intergenic regions containing approximately 85% A/T bp . An insertion element, designated ISM1, was found within the cloned M . smithii DNA located adjacent to the proC complementing region . ISM1 is 1381 bp in length, has 29 bp terminal inverted repeat sequences and contains one major ORF encoded in 87% of the ISM1 sequence . ISM1 is mobile, present in approximately 10 copies per genome and integration duplicates 8 bp at the site of insertion . The duplicated sequences show homology with sequences within the 29 bp terminal repeat sequence of ISM1 . Comparison of our data with sequences from halophilic archaebacteria suggests that 5'GAANTTTCA and 5'TTTTAATATAAA may be consensus promoter sequences for archaebacteria . These sequences closely resemble the consensus sequences which precede Drosophila heat-shock genes (Pelham 1982; Davidson et al . 1983) . Methanogens appear to employ the eubacterial system of mRNA: 16SrRNA hybridization to ensure initiation of translation; the consensus ribosome binding sequence is 5'AGGTGA. Mol Gen Genet, 1985, 198(3), 449 - 55 Genome organization in Halobacterium halobium: a 70 kb island of more (AT) rich DNA in the chromosome; Pfeifer F et al.; The more A + T rich fractionated component (FII DNA) of the Halobacterium halobium genome constitutes one third of the total DNA and upon isolation consists of covalently closed circular DNA (pHH1 and minor cccDNA) and nonsupercoiled sequences . We have investigated the physical organization of the non cccDNA in FII by a chromosome walk using one copy of the halobacterial insertion element ISH1 as a start point . This chromosome walk led to the isolation of 160 kb of chromosomal DNA containing 70 kb of FII DNA covalently linked to more G + C rich sequences (FI DNA) . Copies of three previously characterized insertion elements (ISH1, ISH2, and ISH26) as well as at least 10 other repeated sequences are clustered within this chromosomal FII DNA "island" . Unique sequences are found in the FI DNA flanking the FII DNA island as well as in 40 kb of FI DNA surrounding the bacterio-opsin gene . The presence of pHH1 in H . halobium and closely related species correlates with the occurrence of the characterized chromosomal FII DNA island . Halophilic purple membrane producing isolates YC81819-9, GN101, SB3 and GRA lack pHH1 and the 70 kb FII DNA, but contain all of the FI DNA sequences tested . We propose that pHH1 and this chromosomal FII DNA are characteristic genomic components of H . halobium and closely related species, and, that the 70 kb FII DNA might represent a large insertion in the chromosome of H . halobium and closely related species . The conservation of both FI and FII DNA sequences can be used for strain classification and determination of evolutionary relationships among halo-bacteria. J Bacteriol, 1985 Jan, 161(1), 438 - 41 gamma-Glutamylcysteine and thiosulfate are the major low-molecular-weight thiols in halobacteria; Newton GL et al.; Six representative species of extremely halophilic bacteria were found to contain approximately millimolar concentrations of gamma-glutamylcysteine in the absence of significant glutathione . Thiosulfate also accumulated in the halobacteria, apparently as a major product of cysteine oxidation. J Gen Microbiol, 1985 Jan, 131 ( Pt 1), 165 - 73 Nucleic acid studies on halophilic archaebacteria; Ross HN et al.; DNA-16S rRNA hybridization studies of archaebacterial halophiles revealed nine major groups . High (greater than 45%) DNA-DNA homologies were found only within DNA-rRNA groups . The DNA-DNA homology between the type strains of Halobacterium halobium, Hb . salinarium and Hb . cutirubrum was greater than 70% . The implications for the taxonomy of the extreme halophiles are discussed. Biochem Biophys Res Commun, 1984 Oct 30, 124(2), 423 - 9 Lack of detectable polyamines in an extremely halophilic bacterium; Chen KY et al.; Polyamines (putrescine, spermidine, spermine and other analogs) were not detectable by the dansylation procedure coupled with HPLC analysis in an extremely halophilic bacterium, Halobacterium halobium . Based on the detection limit of this analytical method, we estimated that the polyamine content in H . halobium, if present, was less than 0.06% of that of E . coli . Putrescine uptake and the metabolic conversion of ornithine or arginine to polyamines were negligible in this bacterium . In a H . halobium cell-free extract, a saturated amount of KC1 was needed for poly(U) directed polyphenylalanine synthesis; neither putrescine nor spermidine could replace KC1 . These results suggest that polyamines may play an insignificant role in the growth of this halophilic bacterium. J Bacteriol, 1984 Oct, 160(1), 107 - 11 Protein on the cell surface of the moderately halophilic phototrophic bacterium Rhodospirillum salexigens; Evers D et al.; A cell surface protein (Mr 68,000) of the moderately but obligately halophilic phototrophic bacterium Rhodospirillum salexigens was identified by two independent methods: first, by labeling the cell surface with radioactive iodine and lactoperoxidase, and second, by washing cells in 30% sucrose to remove proteins attached to the cell surface by ionic bonds . The identified protein very likely represents the outermost layer of the cell envelope of R . salexigens as observed by electron microscopy . The protein was isolated . Its isoelectric point was determined to be 4.4; the excess of acidic over basic amino acids was found to be 18.3 mol%; and its average hydrophobicity was 2.26 kJ per residue. J Bacteriol, 1984 Oct, 160(1), 478 - 9 Betaine is the main compatible solute of halophilic eubacteria; Imhoff JF et al.; A number of moderately halophilic bacteria of diverse taxonomic groups have been studied to determine the intracellular concentrations of organic compounds at various salt concentrations . Betaine was accumulated in all of these organisms in proportion to the salinity of the medium, suggesting that this compound plays a major role in osmoregulation. J Bacteriol, 1984 Oct, 160(1), 385 - 90 Effect of chloride and glutamate ions on in vitro protein synthesis by the moderate halophile Vibrio costicola; Kamekura M et al.; Vibrio costicola grown in the presence of different NaCl concentrations contains cell-associated Na+ and K+ ions whose sum is equal to or greater than the external Na+ concentration . In the presence of 0.5 M NaCl, virtually no in vitro protein is synthesized in extracts of cells grown in 1.0 M NaCl . However, we report here that active in vitro protein synthesis occurred in 0.6 M or higher concentrations of Na2SO4, sodium formate, sodium acetate, sodium aspartate, or sodium glutamate, whereas 0.6 M NaF, NaCl, or NaBr completely inhibited protein synthesis as measured by polyuridylic acid-directed incorporation of {14C}phenylalanine . Sodium glutamate, sodium aspartate, and betaine (0.3 M) counteracted the inhibitory action of 0.6 M NaCl . The cell-associated Cl- concentration was 0.22 mol/kg in cells grown in 1.0 M NaCl . Of this, the free intracellular Cl- concentration was only 0.02 mol/kg . Cells contained 0.11 mol of glutamate per kg and small concentrations of other amino acids . All of the negative counterions for cell-associated Na+ and K+ have not yet been determined . In vitro protein synthesis by Escherichia coli was inhibited by sodium glutamate . Hybridization experiments with ribosomes and the soluble (S-100) fractions from extracts of E . coli and V . costicola showed that the glutamate-sensitive fraction was found in the soluble, not the ribosomal, part of the system . The phenylalanyl-tRNA synthetase of V . costicola was not inhibited by 0.5 M or higher concentrations of NaCl; it was slightly more sensitive to high concentrations of sodium glutamate . Therefore, this enzyme was not responsible for the salt response of the V . costicola in vitro protein-synthesizing system. J Biochem (Tokyo), 1984 Aug, 96(2), 413 - 20 Isolation and characterization of halorhodopsin from Halobacterium halobium; Sugiyama Y et al.; Chromoprotein of a light-driven chloride pump, halorhodopsin (HR), was isolated from Halobacterium halobium L-33, which contains HR and "slowly cycling rhodopsin-like pigment" (SR) but lacks bacteriorhodopsin (BR) . The isolation was run in the presence of more than 2 M NaCl, which was required to preserve this halophilic retinal protein . Cell envelope vesicles were washed with Tween-20 to remove 80% of the proteins . The residual membranes were solubilized with 0.5% C12E9, which had little effect on the photochemical activities of HR and SR . HR was purified by passing it through a hydroxyapatite and then a phenyl-Sepharose column in 2 M NaCl and 0.5% C12E9 . The absorption maximum of HR was 578 nm and the ratio of absorbance at 280 nm to 580 nm was 1.52 . The apparent molecular weight of HR was 20,000 on polyacrylamide gel electrophoresis in the presence of SDS . The characteristic, bilobed CD spectrum of HR in the visible region suggested that HR exists as an oligomer in both its membrane-bound and isolated forms. J Bacteriol, 1984 Aug, 159(2), 800 - 2 Aphidicolin inhibits growth and DNA synthesis in halophilic arachaebacteria; Forterre P et al.; Aphidicolin, a specific inhibitor of eucaryotic alpha DNA polymerase, inhibits the growth of halophilic arachaebacteria . In Halobacterium halobium, aphidicolin prevents cell division and DNA synthesis . These results suggest that arachaebacterial replicases are of the eucaryotic type. Biochim Biophys Acta, 1984 Jul 27, 766(1), 77 - 87 Energetics of sodium-dependent alpha-aminoisobutyric acid transport in the moderate halophile Vibrio costicola; Hamaide F et al.; The energetics of alpha-aminoisobutyric acid transport were examined in Vibrio costicola grown in a medium containing the NaCl content (1 M) optimal for growth . Respiration rate, the membrane potential (delta psi) and alpha-aminoisobutyric acid transport had similar pH profiles, with optima at 8.5-9.0 . Cells specifically required Na+ ions to transport alpha-aminoisobutyric acid and to maintain the highest delta psi (150-160 mV) . Sodium was not required to sustain high rates of O2-uptake . Delta psi (and alpha-aminoisobutyric acid transport) recovered fully upon addition of Na+ to Na+-deficient cells, showing that Na+ is required in formation or maintenance of the transmembrane gradients of ions . Inhibitions by protonophores, monensin, nigericin and respiratory inhibitors revealed a close correlation between the magnitudes of delta psi and alpha-aminoisobutyric acid transport . Also, dissipation of delta psi with triphenylmethylphosphonium cation abolished alpha-aminoisobutyric acid transport without affecting respiration greatly . On the other hand, alcohols which stimulated respiration showed corresponding increases in alpha-aminoisobutyric acid transport, without affecting delta psi . Similarly, N,N'-dicyclohexylcarbodiimide (10 microM) stimulated respiration and alpha-aminoisobutyric acid transport and did ot affect delta psi, but caused a dramatic decline in intracellular ATP content . From these, and results obtained with artificially established energy sources (delta psi and Na+ chemical potential), we conclude that delta psi is obligatory for alpha-aminoisobutyric acid transport, and that for maximum rates of transport an Na+ gradient is also required. Appl Environ Microbiol, 1984 Jul, 48(1), 236 - 8 Halophilic Vibrio species from seafish in Senegal; Schandevyl P et al.; Sucrose-positive and sucrose-negative halophilic Vibrio species at counts of up to 10(7)/100 g were isolated from muscles tissue in 27 and 43%, respectively, of 128 seafish from coastal waters in Senegal . Vibrio parahaemolyticus, including 21% urease-positive strains, was the most common isolate, followed by Vibrio alginolyticus, Vibrio vulnificus, Vibrio damsela, and Vibrio fluvialis. Biochim Biophys Acta, 1984 Jun 15, 799(2), 135 - 42 Photoreactivation in pigmented and non-pigmented extreme halophiles; Sharma N et al.; The sensitivity to ultraviolet radiation (254 nm) and the photoreactivability of four pigmented and three colourless strains of the extremely halophilic bacteria Halobacterium cutirubrum and Halobacterium salinarium have been studied . The results with three pigmented/non-pigmented pairs show that the pigments play an accessory role in photoreactivation at low visible light intensities and confirm that they do not provide passive protection against ultraviolet light . Evidence is presented that photoreactivation plays an unexpected direct role in the resistance of extreme halophiles to ultraviolet radiation and that colourless mutants of H . cutirubrum NRC 34001 only arise in cultures that have been both ultraviolet-irradiated and photoreactivated . None of these extreme halophiles is capable of excision repair of ultraviolet damage to DNA. Mikrobiologiia, 1984 May-Jun, 53(3), 520 - 4 {Comparative characteristics of the transport systems of C4-dicarboxylic acids in cultures of the genera Halobacterium and Halococcus}; Zviagintseva IS et al.; The transport systems of the extreme halophilic organisms, Halobacterium and Halococcus, differ to a considerable degree in the kinetic parameters of succinate and fumarate transport, the exchange between exocellular and endocellular labeled dicarboxylates, and the rate at which labeled compounds in the cell are incorporated into cellular metabolism. Infect Immun, 1984 May, 44(2), 326 - 31 Cytolytic activity and virulence of Vibrio damsela; Kreger AS; A correlation was observed between the ability of 19 isolates of Vibrio damsela, a halophilic bacterium recently recognized as a human pathogen, to cause disease in mice and to produce large amounts of a cytolytic toxin in vitro . The yield of toxin in the culture supernatant fluids was optimal during the mid- and late-logarithmic phases of growth in medium containing 0.5% Na+ ion, was stable during the stationary growth phase, and was significantly reduced in culture medium containing greater than or equal to 0.8% Na+ ion, even though Na+ ion concentrations ranging from 0.8% to 2% significantly enhanced growth of the bacterium . The activity in toxin preparations partially purified by ammonium sulfate precipitation was deleteriously affected by heat, low and high pH, proteases, dithiothreitol, and chelating agents, but was unaffected by cholesterol, trypan blue, and mixed gangliosides . The toxin had a molecular weight (estimated by gel filtration) of ca . 57,000 and an isoelectric point of ca . 5.7 and was antigenically distinct from previously described cytolysins produced by Vibrio vulnificus, Vibrio parahaemolyticus, and the El Tor biotype of Vibrio cholerae . Bacteriologically sterile, partially purified toxin preparations were lethal for mice after intraperitoneal, intravenous, and subcutaneous administration, and subcutaneous injection elicited grossly observable changes similar to those observed during the lethal experimental infection caused by subcutaneous injection of V . damsela. Mikrobiyol Bul, 1984 Apr, 18(2), 107 - 13 {Isolation of a moderately halophilic bacterium from Salt Lake, Turkey}; Aksoz N et al.; A moderate halophilic bacterium was isolated from Salt Lake, Turkey . Dundas' complex medium was used for further investigations . The bacterium showed optimal growth in medium containing 8% NaCl . Growth was also detected in media with 0, 5, 12.5, 20 and 25 (%) NaCl. J Infect Dis, 1984 Apr, 149(4), 558 - 61 Clinical features and an epidemiological study of Vibrio vulnificus infections; Tacket CO et al.; Vibrio vulnificus, a recently described halophilic Vibrio species, has been isolated from the blood, wounds, and other skin lesions of patients with primary sepsis or wound infections . Because no study of risk factors for infections with V vulnificus has been reported, a case-control study was performed with the 30 patients from whom V vulnificus isolates were recently submitted to the Centers for Disease Control (Atlanta, Georgia) . Patients with primary sepsis were more likely than controls to have eaten raw oysters recently (P less than .01) and to have a history of liver disease (P less than .02) . Persons with liver disease should be warned that raw oysters are an important source of this life-threatening infection . Patients with wound infections were more likely than controls to have had recent exposure of the skin to salt water or shellfish (P less than .05) . Physicians should therefore consider V vulnificus in the differential diagnosis of severe wound infections with these exposures. Biochem J, 1984 Mar 15, 218(3), 811 - 8 Dihydrolipoamide dehydrogenase from halophilic archaebacteria; Danson MJ et al.; Dihydrolipoamide dehydrogenase has been discovered in the halophilic archaebacteria for the first time . The enzyme from both classical and alkaliphilic halobacteria has been investigated . (1) The enzyme specifically catalysed the stoichiometric oxidation of dihydrolipoamide by NAD+ . Enzymic activity was optimal at 2 M-NaCl and was remarkably resistant to thermal denaturation . (2) The relative molecular masses (Mr) of the native enzyme from the various species of halobacteria were determined to be within the range 112000-120000 . (3) The enzyme exhibited a hyperbolic dependence of catalytic activity on both dihydrolipoamide and NAD+ concentrations . From these steady-state kinetic measurements the dissociation constant (Ks) of dihydrolipoamide was determined to be 57 (+/- 5) microM . (4) The enzyme was only susceptible to inactivation by iodoacetic acid in the presence of its reducing ligands, dihydrolipoamide or NADH . The rate of inactivation followed a hyperbolic dependence on the concentration of dihydrolipoamide, from which the Ks of this substrate was calculated to be 55 (+/- 7) microM . Together with the steady-state kinetic data, the pattern of inactivations is consistent with the involvement in catalysis of a reversibly reducible disulphide bond, as has been found in dihydrolipoamide dehydrogenase from non-archaebacterial species . In eubacterial and eukaryotic organisms, dihydrolipoamide dehydrogenase functions in the 2-oxo acid dehydrogenase complexes . These multienzyme systems have not been detected in the archaebacteria, and, in the context of this apparent absence, the possible function and evolutionary significance of archaebacterial dihydrolipoamide dehydrogenase are discussed. Arch Biochem Biophys, 1984 Feb 15, 229(1), 202 - 11 Interaction of constituent subunits in ribulose 1,5-bisphosphate carboxylase from Aphanothece halophytica; Takabe T et al.; Ribulose 1,5-bisphosphate carboxylase-oxygenase (RuBisCO) from the halophilic cyanobacterium, Aphanothece halophytica, dissociates into catalytic core (large subunit A oligomer) and small subunit B under low ionic strength during sucrose density gradient centrifugation . Supplementation of KCl, NaCl, or K2SO4 ( {I} = 0.3 M) partly prevents the dissociation, the preventive effect of divalent cation salts such as MgCl2 and CaCl2 being more effective than monovalent cation salts . RuBisCO with its higher-plant-type molecular form can be isolated from the cyanobacterial extracts using gradient medium containing 0.3 M KCl, 20 mM MgCl2, and 10 mM CaCl2 . The isolated enzyme contains large subunit A and small subunit B in a molar ratio of approximately 1:1, estimated from the densitometric scanning of Coomassie blue-stained gels . During the second sucrose density gradient centrifugation to remove minor contaminants, a small amount of subunit B is depleted from the holoenzyme . Determination of the molecular weight by equilibrium centrifugation and electron microscopic observation have confirmed that the cyanobacterial RuBisCO has an A8B8-type structure . The enzyme activity per se is found to be sensitive to concentrations of salts, and small subunit B is obligatory for the enzyme catalysis . It has been shown that the more the enzyme activity is inhibited by salts, the tighter the association of subunit B becomes . It is likely that the active enzyme retains the loose conformational structure to such an extent that the dissociable release of subunit B from the holoenzyme in vivo is not allowed. J Clin Microbiol, 1984 Feb, 19(2), 197 - 9 Wound infections caused by Vibrio vulnificus, a marine vibrio, in inland areas of the United States; Tacket CO et al.; Vibrio vulnificus is a halophilic marine vibrio which may produce infection in wounds exposed to seawater or raw shellfish . The Centers for Disease Control has received two isolates from wounds exposed to inland waters, a New Mexico creek and an Oklahoma reservoir . Halophilic organisms were recovered from both the creek and the reservoir, and the water in both sites was found to be brackish . Both clinical isolates of V . vulnificus grew in salt concentrations as low as those found in the creek and reservoir . These cases illustrate the potential for pathogenic halophilic Vibrio species to live in brackish inland waters and produce infections in patients living in inland areas of the United States. Zentralbl Mikrobiol, 1984, 139(6), 435 - 40 Salinity-loving fungi in Egyptian soils . I . Numbers, identities, and halophilism; Radwan SS et al.; The total numbers and the frequencies of fungi in one normal and three saline soils were determined, using a nutrient medium containing sodium chloride concentrations up to 10% (w/v) . The most salinity-tolerant fungi were found to belong to the two genera Aspergillus and Penicillium . Four selected Penicillium isolates showed a typical halophilic behaviour . Their growth was directly proportional to the concentration of sodium chloride in the nutrient medium up to 10% (w/v) . Some of the isolates could tolerate up to 30% sodium chloride in the medium (w/v). J Bacteriol, 1983 Nov, 156(2), 636 - 43 Growth of a marine Vibrio alginolyticus and moderately halophilic V . costicola becomes uncoupler resistant when the respiration-dependent Na+ pump functions; Tokuda H et al.; The growth of Vibrio alginolyticus and V . costicola, which possess respiration-dependent Na+ pumps, was highly resistant to the proton conductor carbonyl cyanide-m-chlorophenyl hydrazone (CCCP), in alkaline growth media, even though the membrane was rendered permeable to H+ . The pH dependence of CCCP-resistant growth was similar to that of the Na+ pump . In contrast, Escherichia coli ML308-225 showed neither Na+ pump activity nor CCCP-resistant growth, even when grown in alkaline, Na+-rich media . These results suggest that certain bacteria possess the Na+ pump and are thus able to grow under the conditions where H+ circulation across the membrane does not take place . Moreover, V . alginolyticus growing in the presence of CCCP maintains normal levels of internal K+, Na+, and H+ . The Na+ pump, therefore, makes the growth of these organisms resistant to CCCP by maintaining the intracellular cation environments. J Bacteriol, 1983 Nov, 156(2), 537 - 44 Proton motive force and Na+/H+ antiport in a moderate halophile; Hamaide F et al.; The influence of pH on the proton motive force of Vibrio costicola was determined by measuring the distributions of triphenylmethylphosphonium cation (membrane potential, delta psi) and either dimethyloxazolidinedione or methylamine (osmotic component, delta pH) . As the pH of the medium was adjusted from 5.7 to 9.0, the proton motive force steadily decreased from about 170 to 100 mV . This decline occurred, despite a large increase in the membrane potential to its maximum value at pH 9.0, because of the loss of the pH gradient (inside alkaline) . The cytoplasm and medium were of equal pH at 7.5; membrane permeability properties were lost at the pH extremes of 5.0 and 9.5 . Protonophores and monensin prevented the net efflux of protons normally found when an oxygen pulse was given to an anaerobic cell suspension . A Na+/H+ antiport activity was measured for both Na+ influx and efflux and was shown to be dissipated by protonophores and monensin . These results strongly favor the concept that respiratory energy is used for proton efflux and that the resulting proton motive force may be converted to a sodium motive force through Na+/H+ antiport (driven by delta psi) . A role for antiport activity in pH regulation of the cytosol can also explain the broad pH range for optimal growth, extending to the alkaline extreme of pH 9.0. Eur J Biochem, 1983 Sep 15, 135(2), 279 - 83 DNA-dependent RNA polymerase from the extremely halophilic archaebacterium Halococcus morrhuae; Madon J et al.; Pure and absolutely DNA-dependent RNA polymerase has been isolated from the extremely halophilic archaebacterium, Halococcus morrhuae . It is composed of five heavy (142 000; 88 000; 73 000; 52 500; and 49 500 Da) and five small components (13 300; 11 200; 10 800; 10 500; 9 900 Da) . The peptides of 49 500 Da and 52 500 Da probably represent one component in different modification states . Single-stranded DNA shows the highest template efficiency, although archaebacterial chromosomal DNAs are efficiently transcribed . Rifampicin, streptolydigin and alpha-amanitin do not inhibit transcription by this enzyme . Heparin permits elongation but not initiation of transcription . The activity of H . morrhuae RNA polymerase is strongly stimulated by glycerol and dimethylsulfoxide. Arch Biochem Biophys, 1983 Sep, 225(2), 713 - 21 Ribulose 1,5-bisphosphate carboxylase from the halophilic cyanobacterium Aphanothece halophytica; Asami S et al.; Various structural and functional properties of ribulose 1,5-bisphosphate carboxylase/oxygenase (RuBisCO) isolated from the halophilic cyanobacterium (blue-green alga) Aphanothece halophytica were reexamined . The ready dissociation of this algal RuBisCO during sedimentation in a linear sucrose density gradient was observed . Low NaCl concentrations promote the dissociation of small subunit (B) from the original native enzyme molecule as evidenced by the sucrose density gradient centrifugation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis . It is thus possible that the intracellular osmoticum of A . halophytica might influence the structural integrity and activity of RuBisCO . The low residual carboxylase activity ascribed to the catalytic core, an oligomer form of the large subunit (A) apparently deficient in small subunit (B), was found to be markedly stimulated by a protein component which appears identical to subunit B . The purification and structural characterization of the catalytic core and subunit B were attempted by step-wise column chromatography on DEAE-cellulose, Utrogel AcA 34, Sephadex G-75, and hydroxylapatite, and at the final stage each component was purified to near homogeneity, although the catalytic core is still associated with a small quantity of subunit B . The addition of subunit B to the catalytic core does not alter the Km (HCO-3, RuBP) values, but Vmax values are markedly enhanced . Sucrose density gradient centrifugation gave a value of 16 S for the catalytic core . The molecular weights of the monomeric forms of the catalytic core (subunit A) and subunit B were 5.0 X 10(4) and 1.4 X 10(4), respectively. Eur J Biochem, 1983 Aug 1, 134(2), 345 - 9 Utilization of energy stored in the form of Na+ and K+ ion gradients by bacterial cells; Brown II et al.; The hypothesis that Na+ and K+ gradients have an energy storing function {V . P . Skulachev (1978) FEBS Lett . 87, 171-176} has been tested in experiments with Escherichia coli, the marine bacterium Vibrio harveyi, an extremely halophilic Halobacterium halobium and a fresh-water cyanobacterium Phormidium uncinatum from Lake Baikal living at an extremely low salt concentration . The capability of these microorganisms to maintain delta microH was compared using motility as a delta microH-supported function . It was found that in all cases the gradient of monovalent cations is competent to prolong the period of active motility after other energy sources are exhausted . Maximal prolongation was found in H . halobium, which in a Na+ medium was still motile when light was switched off for 9 h under anaerobic conditions . In V . harveyi the motility was maintained for 1 h, in E . coli for about 10 min and in Ph . uncinatum for about 2 min . Thus the delta microH buffer capacity of the monovalent cation gradient is proportional to the content of these cations in the habitat . It was also found that in Ph . uncinatum only delta pK is effective, whereas in E . coli and V . harveyi both delta pK and delta pNa are . In E . coli when the K+ release is completed and the cells become motionless, motility can be temporarily restored by adding NaCl which initiates an H+ efflux . Under conditions of exhaustion of energy sources, the Na+ and K+ gradient was shown to stabilize potential in H . halobium cells, measured with a tetraphenylphosphonium probe . In H . halobium and E . coli, the anaerobic ATP level was found to stabilize when the Na+ and K+ gradients were present . Addition of N,N'-dicyclohexylcarbodiimide destabilized this level, which indicated that Na+ and K+ gradients could support de novo ATP synthesis . It is concluded that the data obtained are in agreement with the concept of the energy storing by the Na+ and K+ gradients . Other functions of these gradients and the mechanisms of their formation are discussed. Infect Immun, 1983 Aug, 41(2), 644 - 9 Siderophore production by Vibrio vulnificus; Simpson LM et al.; Previous studies in our laboratory, as well as clinical evidence, have suggested that increased iron levels in the host may be important in infections caused by the halophilic pathogen Vibrio vulnificus . To study iron acquisition, we induced siderophore production by growth in a low-iron medium, and biochemical testing indicated the production of both hydroxamate- and phenolate-type siderophores . The siderophores were extracted from growth filtrates with ethyl acetate (for phenolates) and phenol-chloroform-ether (for hydroxamates) . These extracts enhanced the growth of V . vulnificus when the bacterium was grown in iron-limited medium . The ability of these siderophores to stimulate the growth of Salmonella typhimurium LT-2 enb-7 (a mutant deficient in the biosynthesis of enterochelin) and Arthrobacter flavescens JG-9 (a hydroxamate auxotroph) supported the conclusion that V . vulnificus produces both hydroxamate- and phenolate-type siderophores. J Gen Microbiol, 1983 Jul, 129 (Pt 7), 2129 - 41 The cell cycle of the budding yeast Sterigmatomyces halophilus: culture fractionation by zonal centrifugation and the accumulation of DNA, RNA and protein; Salmon I et al.; Sterigmatomyces halophilus is an unusual budding yeast in which daughter cells are formed, remote from the mother cell, on fine projections called sterigmata . Some fundamental properties of the cell cycle have been explored by separating cells from an exponentially growing culture into size, and thus age, classes by density-gradient centrifugation . Rate separations on high capacity, high resolution, equivolumetric gradients of sucrose, or, alternatively, isopycnic separations on gradients of Urografin revealed consistent and reproducible patterns of accumulation of DNA, RNA and protein through the cell cycle . Total DNA accumulation was stepwise, synthesis occurring late in the cycle, whilst protein accumulated continuously with no evidence for the discontinuities reported in some other lower eukaryotes . Total RNA accumulation, measured either colorimetrically or by long-term incorporation of radioactively-labelled uracil was transiently elevated early in the cycle and then accumulated continuously . A mathematical analysis of the volume distributions of the cells in fractions from the gradients showed that there is a hyperbolic relationship between cell age and size but that, to a first approximation, measurements of cell size (and density) are direct measures of age . The results are discussed with reference to (1) the unusually high buoyant density of this yeast, (2) the resolution of zonal cell separation methods and (3) macromolecular accumulation in the cell cycles of other eukaryotic micro-organisms. Appl Environ Microbiol, 1983 Jul, 46(1), 288 - 90 Incidence and level of Vibrio parahaemolyticus associated with freshwater plankton; Sarkar BL et al.; We isolated Vibrio parahaemolyticus from plankton samples collected from different freshwater areas in the vicinity of Calcutta, India . Levels of this organism in association with freshwater plankton were low (less than 90 organisms per g) . All of the 16 strains of V . parahaemolyticus isolated in this study were Kanagawa negative, and all except 1 were untypable . The occurrence of V . parahaemolyticus in association with freshwater plankton suggests that adsorption onto plankton may aid the survival of this moderately halophilic organism in freshwater milieus. J Diarrhoeal Dis Res, 1983 Jun, 1(2), 87 - 9 A rapid test for the identification of Vibrio cholerae in stools; Lam SY; PIP: A rapid test to identify Vibrio cholerae in stools has been developed . The test depends on the ability of the vibrios to multiply in a specially designed medium in the presence of other intestinal bacteria and to agglutinate against specific antisera directly . The culture medium consisted of 2 parts: agar and broth . Aseptic condition was not required . A 0.5 ml amount of a diluted stool suspension was added to an equal volume of molten agar in freeze drying glass ampules and left to set while 0.3 ml of broth was allowed to run down the ampule slowly to cover the agar surface . The ampule was incubated at 37 degrees C without shaking for 2 to 4 hours or until a slight turbidity of bacterial growth became visible . A drop of V . cholerae antiserum was then added and left to react at room temperature . In a cholera stool, agglutination appeared as a suspension of fine particles within 1 hour . In view of the simple technique, low cost, and easy preparation, the test can be performed in a laboratory with minimal facilities . Results obtained for the cholera and halophilic vibrios indicate a close correlation between the present method and the slide agglutination test . South Med J, 1983 May, 76(5), 571 - 4 Extraintestinal infections due to halophilic vibrios; Armstrong CW et al.; To compare the clinical and epidemiologic features, we reviewed the hospital records and interviewed 18 patients with extraintestinal infections caused by three species of halophilic vibrios . Vibrio vulnificus, the organism most frequently isolated in Virginia during the six-year study period, caused primary septicemia in three patients . Fifteen patients had soft tissue infections, most of which followed injuries that were contaminated by seawater and mostly caused by V vulnificus and V parahaemolyticus . All infections occurred during the warm months of the year, and in most cases were an occupational or recreational hazard of fishing. J UOEH, 1983 Mar 1, 5(1), 95 - 100 {Fatal Vibrio vulnificus infection in a patient with aplastic anemia}; Yoshida S et al.; The patient was a 59-year-old man who had been in hospital suffering from aplastic anemia with transfusion hemosiderosis . Sudden onset of weakness, shaking chills and headache was observed after his staying out overnight on July 25, 1981 . His temperature was 39.3 degrees C and he complained of abdominal pain and abdominal distension . His blood pressure dropped to a dangerous level and tonic convulsions that had begun in the upper body gradually extended to the whole body and he died 23 hours after his return . V . vulnificus was isolated by the blood culture performed before death . During his stay away from the hospital, he had eaten raw cuttlefish, which was considered to be the source of infection . V . vulnificus is one of the halophilic marine vibrios and is isolated frequently in summertime from the sea foods and sea water near Japan . It has been disclosed that the presence of underlying diseases such as liver cirrhosis, hemochromatosis can predispose a person to fatal sepsis by V . vulnificus . In this case, besides leukocytopenia, the presence of hemosiderosis induced by many transfusions was considered to be a major cause leading to the fulminating course of the disease. Arch Inst Pasteur Tunis, 1983 Mar-Sep, 60(1-2), 13 - 9 {Characteristics of Vibrio metschnikovii isolated in Tunisia}; Khemiri F et al.; We report the isolation in Tunisia of two strains of Vibrio metschnik ovii from waters; These strains present some atypical characteristics the most important being their weak halophilie property. Biochim Biophys Acta, 1983 Jan 20, 739(1), 73 - 8 A comparison of liquid-holding recovery and photoreactivation in halophilic and non-halophilic bacteria; Fitt PS et al.; The ability of the extreme halophile Halobacterium cutirubrum to recover from the effects of ultraviolet radiation during liquid holding in the dark in non-nutrient medium has been compared with that of (i) a moderately halophilic bacterium (NRC 41227) and (ii) Escherichia coli B . The photoreactivabilities of all three bacteria have also been studied . The extreme halophile was incapable of liquid-holding recovery in these conditions, in marked contrast to both E . coli B and the moderate halophile, and also failed to recover when held in nutrient medium in the dark . These results strongly support the hypothesis that H . cutirubrum lacks DNA excision repair . It was also found that ultraviolet-irradiated H . cutirubrum could be almost completely photoreactivated from any level of survival in the range 10(-4)-80%, provided exposure to visible light was not delayed, whereas the moderate halophile resembled E . coli B and had a comparatively limited capacity for photoreactivation. J Clin Microbiol, 1982 Nov, 16(5), 821 - 5 Chronic granulomatous disease: fatal septicemia caused by an unnamed gram-negative bacterium; Seger RA et al.; A 2-year-old boy with proven X-linked chronic granulomatous disease was placed under continuous co-trimoxazole prophylaxis . He remained free of infection for 4 years . At age 6.25 years, he suddenly developed a fever with no localizing signs and died 16 days later in septic shock . A gram-negative, catalase-positive, halophilic, aerobic bacterium was cultured from blood, bone marrow, and ascitic fluid . This organism could not be identified in microbiological laboratories in Europe and the United States . Its biochemical features indicate that it may belong to a species which has not previously been described. Eur J Biochem, 1982 Nov, 128(1), 223 - 30 Thermoacidophilic archaebacteria contain bacterial-type ferredoxins acting as electron acceptors of 2-oxoacid:ferredoxin oxidoreductases; Kerscher L et al.; Thermoplasma acidophilum and Sulfolobus acidocaldarius contain coenzyme A-acylating 2-oxoacid:ferredoxin oxidoreductases similar to those found in halophilic archaebacteria . A common feature of these enzymes is the formation of a free radical intermediate in the course of the catalytic cycle . The electron-accepting ferredoxins and a similar protein from Desulfurococcus mobilis have been purified and characterized . In contrast to the {2Fe-2S} ferredoxin of Halobacterium halobium, the ferredoxins of thermoacidophilic archaebacteria most likely contain two {4Fe-4S}2 + (2 + .1 +) clusters per molecule . Properties of these proteins are compared with respect to the evolution of archaebacteria. Biochemistry, 1982 Oct 12, 21(21), 5189 - 95 Small-angle x-ray scattering study of halophilic malate dehydrogenase; Reich MH et al.; Malate dehydrogenase from the organism Halobacterium marismortui was studied in solutions of varying salt concentration by using a small-angle X-ray system employing a linear position sensitive detector . Considerations pertaining to the study of absorbing multicomponent solutions are presented . The radius of gyration of halophilic malate dehydrogenase was found to be 31.8 +/- 0.6 A and the shape of the molecule spheroidal . The scattering from prolate ellipsoids of eccentricity between 1 and 2 best fitted the data while for oblate ellipsoids the scattering was best fitted for eccentricities between 1 and 0.5 . No significant change in the radius of gyration or anisotropy of halophilic malate dehydrogenase was found in the range of NaCl concentrations studied (1-4 M) . The contrast matching electron density was found to be 0.407 +/- 0.002 e/A3 . A parallel study of bovine serum albumin yielded within experimental error a similar contrast matching electron density of 0.404 +/- 0.006 e/A3 . This information combined with the diffusion coefficient and the amount of water and salt associated with halophilic malate dehydrogenase renders the existence of an outer hydration shell unlikely . The data are rather consistent at low resolution with a spheroidal particle of uniform electron density. Appl Environ Microbiol, 1982 Oct, 44(4), 820 - 4 Effect of temperature and salinity on Vibrio (Beneckea) vulnificus occurrence in a Gulf Coast environment; Kelly MT; Vibrio (Beneckea) vulnificus is a recently recognized halophilic organism that may cause serious human infections . Patients infected with V . vulnificus often have a history of exposure to the sea, suggesting that the organism may be a common inhabitant of marine environments . Twenty-one inshore sites around Galveston Island in the Gulf of Mexico were cultured for V . vulnificus over a 12-month period . The organism was recovered from all but one of the sites at some time during the study . It was frequently isolated during the summer and fall from environments of relatively low salinity (7 to 16%) . V . vulnificus was rarely isolated from any of the sites during the winter months, when water temperatures dropped below 20 degrees C . In vitro growth characteristics of environmental isolates of V . vulnificus demonstrated salinity optima of 1.0 to 2.0% NaCl and a temperature optimum of 37 degrees C . These growth characteristics may account for the seasonal and geographical variations in occurrence of the organism . Overall, the results of these studies indicate that V . vulnificus is commonly found in Gulf Coast environments and that the occurrence of the organism is favored by warm temperatures and relatively low salinity. Appl Environ Microbiol, 1982 Oct, 44(4), 994 - 5 Application of halophilic nuclease H of Micrococcus varians subsp . halophilus to commercial production of flavoring agent 5'-GMP; Kamekura M et al.; RNA was degraded at 60 degrees C for 24 h by halophilic nuclease H in supernatants from broth cultures of Micrococcus varians subsp . halophilus containing 12% NaCl . Since contaminating 5'-nucleotidase exhibited almost no activity under these conditions, the 5'-GMP formed could be recovered from the reaction mixture, and the yield was 805 mg from 5 g of RNA. Nature, 1982 Sep 9, 299(5879), 182 - 5 High-frequency genomic rearrangements involving archaebacterial repeat sequence elements; Sapienza C et al.; Halobacterium halobium is an obligately halophilic archaebacterium of interest to molecular biologists for many reasons, one of which is the unexplained high frequency (10(-4)-10(-2) mutants per cell plated) at which it yields readily identifiable and unstable mutants . We showed previously that the genome of H . halobium contains many (greater than 50) families of repeated sequences whose members are dispersed on both chromosome and plasmid . Here we report that most if not all of the members of most of these repeat sequence families effect or are affected by spontaneous genomic rearrangements . Quantitative analyses show that such repeat sequence-associated rearrangements (which may be of several kinds) occur at high frequencies (greater than 4 x 10(-3) events per family per cell generation), while unique-sequence DNAs are physically stable . The presence of so many families of elements of such great instability in the halobacterial genome gives it an unusual degree of structural and perhaps functional plasticity. Med Hypotheses, 1982 Sep, 9(3), 241 - 57 Biochemical response to change in the environment and the nature of "essential" hypertension; Myers JB; The abnormality of Na+, K+-cotransport detected in erythrocytes of patients with "essential" hypertension, appears to be an inherited biochemical disorder characteristic of the disease . This explains several features of "essential" hypertension . However, characteristics of the kinetics of this Na+ transport system are similar to characteristics of enzymes in halophilic organisms, which live in a high saline environment . Cell Na+ is increased in patients with "essential" hypertension and in halophilic organisms . This suggests that the enzyme characteristics are response mechanisms to maintain extracellular Na+ concentration within an optimal range . Based on this view two assumptions of biochemical response have been put forward which form the biochemical basis of a general biological theory . The implications of this for understanding the nature of "essential" hypertension are discussed . To explain the nature of the inheritance of the Na+, K+-cotransport defect in erythrocytes of patients with "essential" hypertension, a theory of acquired genetic transmission called "improvisation" theory is proposed . Improvisation may be the mechanism whereby new gene formation occurs, and be the mechanism for evolution of species if successful reproduction of offspring is allowed to continue. J Bacteriol, 1982 Sep, 151(3), 1532 - 42 Box-shaped halophilic bacteria; Javor B et al.; Three morphologically similar strains of halophilic, box-shaped procaryotes have been isolated from brines collected in the Sinai, Baja California (Mexico), and southern California (United States) . Although the isolates in their morphology resemble Walsby's square bacteria, which are a dominant morphological type in the Red Sea and Baja California brines, they are probably not identical to them . The cells show the general characteristics of extreme halophiles and archaebacteria . They contain pigments similar to bacteriorhodopsin which apparently mediate light-driven ion translocation and photophosphorylation. Can J Microbiol, 1982 Aug, 28(8), 916 - 21 Bacteriophages of Halobacterium halobium: isolated from fermented fish sauce and primary characterization; Pauling C; BActeriophages infecting extremely halophilic bacteria of the genus Halobacterium have been isolated from fermented anchovy sauce . Two distinct phages, designated Hh-1 and Hh-3, have been characterized . Both Hh-1 and Hh-3 are more tolerant of suspension in solutions of low ionic strength that their host bacteria . Both Hh-1 and Hh-3 have the ability to establish a carrier state upon infection of sensitive cells of H . halobium . Bacterial cells infected with phage in the carrier state are viable, produce phages, are immune to superinfection with homologous phages, yet remain fully capable of supporting heterologous phages . These properties suggest that the halophages are well adapted to survival in environments in which the salinity is subject to rapid changes of considerable magnitude. Appl Environ Microbiol, 1982 Aug, 44(2), 423 - 7 Diluent composition for use of API 20E in characterizing marine and estuarine bacteria; MacDonell MT et al.; Nine chemically defined inoculation diluents, with compositions ranging from 0.85% NaCl to 35% marine salts, were used to evaluate the influence of diluent composition on the biochemical profiles of 30 marine and estuarine bacterial strains, including species of Vibrio, Aeromonas, Allomonas, and Photobacterium . Results demonstrated that a 20% marine salts diluent enabled the characterization of halophilic strains normally nonreactive by the API 20E system . Furthermore, the use of 20% marine salts showed that certain environmental isolates, identifiable as Vibrio parahaemolyticus by the recommended clinical inoculation procedure, were Vibrio vulnificus . An analysis of the profiles provided by the nine diluents indicates that the API 20E system, modified by the use of a diluent composed of 20% marine salts and incubated at 22 degrees C, can provide a reliable tool for the rapid characterization of marine and estuarine bacterial isolates. J Clin Microbiol, 1982 Jul, 16(1), 195 - 6 Panophthalmitis caused by Vibrio parahaemolyticus; Tacket CO et al.; We report a case of Vibrio parahaemolyticus panophthalmitis which resulted from contamination of a wound with water from a pond in inland Georgia . The pond was on the property of an oil refinery which receives crude oil from southern Mississippi . Cultures of the pond water 5 years later did not yield V . parahaemolyticus, but did yield non-O1 V . cholerae and had 0.28% sodium chloride content . V . parahaemolyticus may have been introduced into the pond along with oil transported from the Gulf of Mexico, and growth of this halophilic species may have been supported by salt from spilled crude oil. J Bacteriol, 1982 May, 150(2), 851 - 60 Ultrastructure of square bacteria from a brine pool in Southern Sinai; Kessel M et al.; The square bacterium discovered by Walsby (Nature {London} 283:69-71, 1980) has been shown to possess the ultrastructural features of a typical halophile . The cell wall is comprised of regularly arranged subunits demonstrated by thin sectioning, shadowed replicas, and negative staining . Optical diffraction confirms the existence of both hexagonal and tetragonal arrangements of the cell wall subunits and also of different lattice constants and suggests a mixed population of bacteria. J Clin Microbiol, 1982 Mar, 15(3), 395 - 401 Identification of Vibrio hollisae sp . nov . from patients with diarrhea; Hickman FW et al.; The name Vibrio hollisae (synonym = Special Bacteriology group EF-13) is proposed for a new group of 16 strains that occurred in stool cultures of patients with diarrhea . V . hollisae is a small gram-negative rod, which is motile with a single polar flagellum . No lateral or peritrichous flagella were observed, even when it was grown on a solid medium . Sodium chloride is required for growth, so V . hollisae is a halophilic vibrio . Strains were positive (36 degrees C, 24 or 48 h) for oxidase (Kovacs), indole production, nitrate reduction to nitrite, and fermentation of D-glucose (acid, no gas), L-arabinose, D-galactose, and D-mannose . Strains were negative for the following tests often used in enteric bacteriology: lipase (corn oil); deoxyribonuclease; gelatinase; methyl red; Voges-Proskauer; utilization of citrate, acetate, and malonate; L-lysine decarboxylase (Mollers); L-ornithine decarboxylase (Mollers); L-arginine dihydrolase (Mollers); growth in KCN medium; and acid production from D-adonitol, D-arabitol, cellobiose, dulcitol, erythritol, glycerol (25% delayed positive at 7 days), i-(myo)-inositol, lactose, maltose, D-mannitol, melibiose, alpha-methyl-D-glucoside, mucate, raffinose, L-rhamnose, salicin, D-sorbitol, sucrose, trehalose, and D-xylose . None of the strains was motile (semisolid medium) at 36 degrees C at 48 h, but by 7 days 88% were motile . The strains did not grow within 2 days when plated on thiosulfate-citrate-bile salts-sucrose (TCBS) agar or MacConkey agar, but they grew on sheep blood agar and marine agar . By DNA-DNA hybridization (75 degrees C, hydroxyapatite with (32)P), V . hollisae was only 0 to 4% related to 21 named species in Vibrio and Photobacterium . The type strain is designated ATCC 33564, which has a mean guanineplus-cytosine content in DNA of 50 mol% . With the disk diffusion method V . hollisae had relatively large zones of inhibition around penicillin, ampicillin, carbenicillin, cephalothin, colistin, polymyxin B, streptomycin, kanamycin, gentamicin, tetracycline, chloramphenicol, and sulfadiazine . Future studies should focus on the isolation of this new vibrio and its ecology and relationship to human diseases. J Bacteriol, 1982 Mar, 149(3), 808 - 15 Role of membrane-bound 5'-nucleotidase in nucleotide uptake by the moderate halophile Vibrio costicola; Bengis-Garber C et al.; Intact cells of Vibrio costicola hydrolyzed ATP, ADP, and AMP . The membrane-bound 5'-nucleotidase (C . Bengis-Garber and D . J . Kushner, J . Bacteriol . 146:24-32, 1981) was solely responsible for these activities, as shown by experiments with anti-5'-nucleotidase serum and with the ATP analog, adenosine 5'-(beta gamma-imido)-diphosphate . Fresh cell suspensions rapidly accumulated 8-14C-labeled adenine 5'-nucleotides and adenosine . The uptake of ATP, ADP, and AMP (but not the adenosine uptake) was inhibited by adenosine 5'-(beta gamma-imido)-diphosphate similarly to the inhibition of the 5'-nucleotidase . Furthermore, the uptake of nucleotides had Mg2+ requirements similar to those of the 5'-nucleotidase . The uptake of ATP was competitively inhibited by unlabeled adenosine and vice versa; inhibition of the adenosine uptake by ATP occurred only in the presence of Mg2+ . These experiments indicated that nucleotides were dephosphorylated to adenosine before uptake . The hydrolysis of {alpha-32P}ATP as well as the uptake of free adenosine followed Michaelis-Menten kinetics . The kinetics of uptake of ATP, ADP, and AMP also each appeared to be a saturable carrier-mediated transport . The kinetic properties of the uptake of ATP were compared with those of the ATP hydrolysis and the uptake of adenosine . It was concluded that the adenosine moiety of ATP was taken up via a specific adenosine transport system after dephosphorylation by the 5'-nucleotidase. Nature, 1982 Feb 4, 295(5848), 384 - 9 Unusual physical organization of the Halobacterium genome; Sapienza C et al.; The genomes of the extremely halophilic bacteria, Halobacterium halobium and Halobacterium volcanii, contain many repeated sequences . These sequences comprise many families, seem to be highly mobile and are arranged in both clustered and dispersed fashions within these genomes . At least some repeated sequences are more strongly conserved between the two species than are unique sequence DNAs. J Biochem (Tokyo), 1982 Feb, 91(2), 695 - 701 Hybrid ATPase's formed from subunits of coupling factor F1's of Escherichia coli and thermophilic bacterium PS3; Takeda K et al.; ATPase complexes were reconstituted from homologous and heterologous combinations of alpha, beta, and gamma subunits of coupling factor ATPase TF1 of thermophilic bacterium PS3 and EF1 of Escherichia coli . TF1 and alpha beta gamma complex reconstituted from TF1 subunits were thermostable and activated by methanol, sodium dodecyl sulfate and anions and they were halophilic, whereas EF1 and its three-subunit complex did not show these properties . The hybrid ATPase alpha T beta T gamma E (complex of the alpha and beta subunits of TF1 and the gamma subunit of EF1) showed closely similar properties to TF1 except for thermostability, while alpha E beta E gamma T (alpha and beta from EF1 and gamma from TF1) had similar properties to EF1 . These results suggest that alpha and/or beta is required for the properties of F1 . The complex alpha E beta T gamma E showed similar properties to EF1 except for its optimum pH: this complex had a broad pH optimum at about pH 7, whereas EF1 had an optimum at pH 8.5 . No hybrid complexes were thermostable, suggesting that all three subunits of TF1 are required for heat stability . These hybrids showed higher halophilicity than EF1, although they were less halophilic than TF1 . The hybrid enzymes studied here are the first thermophilic-mesophilic hybrid enzymes obtained. Crit Rev Microbiol, 1982, 10(1), 77 - 124 Vibrio parahaemolyticus and related halophilic Vibrios; Joseph SW et al.; Approximately 30 years have elapsed since Dr . Fujino's original discovery that Vibrio parahaemolyticus (then termed Pasteurella parahemolytica) was the cause of "summer diarrhea" in Japan . Since that finding, V . parahaemolyticus has been established as a cause of gastroenteritis in numbers and places approaching global proportions . It has been isolated in marine and estuarine areas almost worldwide and despite its halophilic nature, V . parahaemolyticus has been isolated from saline-free waters . The relationship of this organism to the environment reveals a close association with other marine organisms especially copepods on which the Vibrios depend for survival in winter months and growth in summer months . There is a uniquely provocative disparity between human strains of V . parahaemolyticus which are Kanagawa phenomenon (KP) positive and the environmental strains which to a large extent are KP negative, the significance being that pathogenicity is measured according to the Kanagawa phenomenon (hemolytic activity) reaction . The hemolysin of the pathogenic strains is a thermostable, cardiotoxic protein, which thus far has not been implicated in the mechanism(s) which causes human gastroenteritis . The interest in this organism has been widened in recent years by the finding that similar organisms, V . alginolyticus, lactose positive vibrios and group F vibrios also cause serious disease in humans. J Mol Evol, 1982, 18(2), 109 - 14 Taxonomic relations between archaebacteria including 6 novel genera examined by cross hybridization of DNAs and 16S rRNAs; Tu JK et al.; DNAs from 16 species of archaebacteria including 6 novel isolates were hybridized with 16S rRNAs from 7 species representing different orders or groups of the urkingdom of archaebacteria . The yields, normalized for the number of genes per microgram of DNA, and the temperature stabilities of all hybrids were determined and related to each other . A taxonomic tree constructed from such fractional stability data reveals the same major divisions as that derived from comparative cataloging of 16S rRNA sequences . The extreme halophiles appear however as a distinct order besides the three known divisions of methanogens . The methanogens, the halophiles and Thermoplasma form one of two clearly recognizable branches of the archaebacterial urkingdom . The order represented by Sulfolobus and the related novel order Thermoproteales form the other branch . Three novel genera, Thermoproteus, Desulfurococcus and the "stiff filaments" represent three families of this order . The extremely thermophilic methanogen Methanothermus fervidus belongs to the Methanobacteriales . SN1, a methanogen from Italy, appears as another species of the genus Methanococcus . Another novel methanogen, M3, represents a genus or family of the order Methanomicrobiales. Biochemistry, 1981 Nov 10, 20(23), 6536 - 43 Structural stability of halophilic proteins; Rao JK et al.; An examination of halobacterial amino acids exchanges as they appear in the known Spirulina platensis {2Fe-2S} ferredoxin tertiary structure indicated that most of the additional acidic residues of the halophiles occurred on the external surface of the alga structure; however, further negative changes were not placed in the ferredoxin active site region . A statistical investigation of the amino acid compositions of seven halophile and nonhalophile protein counterparts indicated that the bulkiness of amino acids used by halophiles is considerably reduced and that the overall hydrophobicity of halophilic and non halophilic molecules was essentially the same . It is suggested that the principal mode of structural stabilization for halophilic proteins is effective competition with the cytoplasmic salt for water through utilization of many external carboxyl groups of glutamic and aspartic acids . A reduction is residue bulkiness would prevent inactivation in the presence of the high molarity, antichaotropic KCl . Halophilic functionality is preserved through avoidance of additional negative charge at the active site surface. J Bacteriol, 1981 Oct, 148(1), 352 - 60 Walsby's square bacterium: fine structure of an orthogonal procaryote; Stoeckenius W; The "square" bacterium, first described by Walsby from brine collected at the Red Sea shore {A . E . Walsby, Nature (London) 283:69-71, 1980} was examined by electron microscopy . The cells appeared as flat rectangular boxes in scanning electron micrographs . In sections and freeze-fracture preparation, the edges looked more rounded . The thickness apparently remains constant as the cells grow and divide . Their sides were a few micrometers long, but the cells were only 0.25 micrometers thick . They showed typical procaryote structure, with a regular cell wall and a gas vacuole fine structure similar to that of other halophilic procaryotes . The inner fracture faces of the cell membrane showed a much denser population of intramembrane particles than the outer fracture faces, but no patches of purple membrane, despite the presence of bacteriorhodospin-like pigment in the cell suspension . Morphologically identical cells have been found in brine from Baja California, Mexico. Eur J Biochem, 1981 Sep 1, 118(3), 471 - 7 Structure and activity of malate dehydrogenase from the extreme halophilic bacteria of the Dead Sea . 2 . Inactivation, dissociation and unfolding at NaCl concentrations below 2 M . Salt, salt concentration and temperature dependence of enzyme stability; Pundak S et al.; The stability of halophilic malate dehydrogenase increases with increasing salt concentration and with decrease in temperature . Stabilization by various salts, at high salt concentrations, follows the Hofmeister series . The enzyme inactivation rates closely match dissociation of the dimeric enzymes into monomeric subunits and unfolding of the polypeptide chains, as followed by velocity sedimentation, light scattering and circular dichroism measurements . The alpha-helix content goes to zero upon denaturation . Unusual water and salt binding properties of the native enzyme (cf . preceding paper, in this journal) are believed to be largely lost upon enzyme dissociation and unfolding . The properties thus seem to be associated with the intact structure of the enzyme. Eur J Biochem, 1981 Sep 1, 118(3), 463 - 70 Structure and activity of malate dehydrogenase from the extreme halophilic bacteria of the Dead Sea . 1 . Conformation and interaction with water and salt between 5 M and 1 M NaCl concentration; Pundak S et al.; Large-scale growth of extreme halophilic bacteria from the Dead Sea and purification of malate dehydrogenase (and other proteins) in quantities of hundreds of milligrams makes possible a detailed study of the adaptation to high salt . Halophilic malate dehydrogenase is stable at 20 degrees C in NaCl solutions between 2.5--5 M . Below 2.5 M NaCl time-dependent inactivation, paralleled by structural changes, sets in . Within the time scale of the sedimentation, diffusion and circular dichroism experiments discussed here, it was possible to analyze data corresponding to the active halophilic malate dehydrogenase between 1 M and 5 M NaCl . The striking observation was that rather minor conformation changes were observed over the whole range, yet the special properties of the halophilic enzyme seem to be related to its capacity of associating with unusually large amounts of water and of salts, quite distinct from non-halophilic counterparts . These special properties seem to be related to the intact structure of the protein . Some parallel properties of halophilic glutamate dehydrogenase are also discussed. J Bacteriol, 1981 Aug, 147(2), 282 - 8 Immunological comparison of ribosomal proteins from archaebacteria; Schmid G et al.; Antisera were raised in rabbits against ribosomal proteins of Methanobacterium bryantii and used to analyze immunological relationsh