J La State Med Soc, 1991 Dec, 143(12), 27 - 8 Vibrio vulnificus peritonitis . A unique case; Holcombe DJ; Louisiana is justifiably famous for the seafood harvested from its coastal waters . Unfortunately, undesirables accompany this harvest . The author presents a case of peritonitis due to vibrio vulnificus which followed ingestion of raw oysters. Gene, 1991 Dec 1, 108(1), 31 - 7 Genetic analysis of the export of an extracellular DNase of Vibrio cholerae using DNase-beta-lactamase fusions; Focareta T et al.; A series of C-terminal deletions of the dns-encoded extracellular deoxyribonuclease (DNS) of Vibrio cholerae, fused to the mature form TEM beta-lactamase (Bla) has been used to analyse the export of the DNase in both V . cholerae and Escherichia coli . All hybrid proteins were localized to the periplasmic space in E . coli and V . cholerae, with specific cleavage of the DNS-Bla fusion occurring in V . cholerae . Periplasmic accumulation of wt DNS was also seen in V . cholerae when present on a multicopy plasmid . DNS fusions retaining all six Cys residues of DNS displayed both DNase and Bla enzymatic activity . While hybrid proteins were unable to be secreted across the outer membrane in V . cholerae, the cleaved (active) DNS portion of these proteins was exported . Taken together, these data suggest that the periplasmic form seen in E . coli is a normal intermediate also seen in V . cholerae, and that the lack of secretion machinery in E . coli prevents further export across the outer membrane . Although the DNS portion of the protein fusions must be able to interact with secretion genes, the whole fusion proteins are not exported. Microb Pathog, 1991 Dec, 11(6), 433 - 41 Identification of a mannose-binding pilus on Vibrio cholerae El Tor; Jonson G et al.; The mannose-sensitive hemagglutinin (MSHA) that is associated with Vibrio cholerae strains of El Tor biotype is identified as a pilus composed of subunits with a molecular mass of approximately 17 kDa . In immunoelectron microscopy, a monoclonal antibody against MSHA that inhibited El Tor vibrio-mediated mannose-sensitive agglutination of chicken erythrocytes or El Tor bacterial binding to mannose-coated agarose beads, bound specifically to repetitive subunits along typical fimbriae extending from the surface of El Tor vibrios . No such pili were seen on the surface of MSHA negative classical vibrios, although non-surface exposed fimbrial subunits could be demonstrated in these bacteria by immunoblotting techniques. Mol Gen Genet, 1991 Dec, 230(3), 385 - 93 The beta subunit polypeptide of Vibrio harveyi luciferase determines light emission at 42 degrees C; Escher A et al.; The nucleotide sequence of the luxA and luxB genes encoding the alpha beta heterodimeric luciferase from thermotolerant Vibrio harveyi CTP5 was determined . The DNA sequence of the CTP5 luxA and luxB genes is identical to the DNA sequence of the luxA and luxB genes from mesophilic V . harveyi MAV (B 392), with minor exceptions . The sequence differences result in 5 amino acid substitutions in the alpha subunit polypeptide and 7 amino acid substitutions in the beta subunit polypeptide . Escherichia coli cells grown on solid medium and expressing CTP5 or MAV luxAB genes emit similar amounts of light at 37 degrees C, while at 42 degrees C cells containing CTP5 luxAB genes show more than tenfold increased bioluminescence compared to cells with MAV luxAB genes . When grown in liquid medium E . coli cells with CTP5 or MAV luxAB genes emit equivalent amounts of light at 37 degrees C; however, in liquid medium at 42 degrees C cells containing CTP5 luxAB genes show only three times higher bioluminescence than cells with MAV luxAB genes . Expression of T7 promoter-linked hybrid luxAB transcriptional units luxACTP5-luxBMAV and luxAMAV-luxBCTP5 in E . coli reveals that (i) the MAV luxB gene product is responsible for the decreased activity of MAV luciferase at 42 degrees C; (ii) the CTP5 luxB gene encodes the information required for most of the increased activity of CTP5 luciferase relative to MAV luciferase at 42 degrees C; and (iii) E . coli cells containing MAV luxB gene show an increase in bioluminescence when grown in liquid medium at 42 degrees C, which coincides with elevated GroEL chaperonin levels.(ABSTRACT TRUNCATED AT 250 WORDS) Biochemistry, 1991 Nov 26, 30(47), 11255 - 62 Functional consequences of site-directed mutation of conserved histidyl residues of the bacterial luciferase alpha subunit; Xin X et al.; The available sequences for the different bacterial luciferases reveal five conserved histidyl residues at positions 44, 45, 82, 224, and 285 of the alpha subunit . Ten variants of Vibrio harveyi luciferase were obtained by selective site-directed mutations of these five histidines . The essentiality of alpha His44 and alpha His45 was indicated by 4-7 orders of magnitude of bioluminescence activity reductions resulting from the substitution of either histidine by alanine (alpha H44A or alpha H45A), aspartate (alpha H44D or alpha H45D), or lysine (alpha H45K) . Moreover, alpha H44A and alpha H45A were distinct from the native luciferase in thermal stabilities . Mutations at the other three positions also resulted in activity reductions ranging from a fewfold to 3 orders of magnitude . Despite these widely different bioluminescence light outputs, mutated luciferases exhibited, in nonturnover in vitro assays, light emission decay rates mostly similar to that of the native luciferase using octanal, decanal, or dodecanal as a substrate . This is attributed to a similarity in the catalytic rate constants of the light-emitting pathway for the native and mutated luciferases, but various mutated luciferases suffer in different degrees from competing dark reaction(s) . In accord with this interpretation, the bioluminescence activities of mutated luciferases showed a general parallel with the relative stabilities of their 4a-hydroperoxyflavin intermediate species . Furthermore, the drastically reduced bioluminescence activities for luciferases with the alpha His44 or alpha His45 substituted by aspartate, alanine, or lysine were accompanied by little or no activities for consuming the aldehyde substrate.(ABSTRACT TRUNCATED AT 250 WORDS) Zh Mikrobiol Epidemiol Immunobiol, 1991 Nov, (11), 11 - 3 {The lipids of phosphorescent Vibrio albensis bacteria}; Lebedev KK et al.; The lipid composition of fluorescent vibrios, V . eltor and nonagglutinating vibrios has been studied . In the fraction of polar lipids phosphatidylethanolamine, phosphatidylinositol and cardiolipin and in the fraction of neutral lipids monoglycerides, free fatty acids, diglycerides, triglycerides, sterol esters have been identified . The fatty acid composition of some classes of neutral lipids have been determined . Both similarity and differences between the strains under study in their lipid and fatty acid composition have been established. Chem Pharm Bull (Tokyo), 1991 Nov, 39(11), 3067 - 70 Purification and some properties of inducible lysine decarboxylase from Vibrio parahaemolyticus; Yamamoto S et al.; Inducible lysine decarboxylase from Vibrio parahaemolyticus AQ 3627 was purified to apparent homogeneity and characterized . The enzyme displayed a molecular weight of 531000 by gel filtration and 79000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis . The enzyme required pyridoxal phosphate as a cofactor, and the pH optimum was 5.5 . The Km value for L-lysine was 3.2 mM, and the enzyme was inhibited by 6-aminocaproic acid and alpha-fluoromethyl analogs of cadaverine . delta-Hydroxylysine and S-aminoethyl-L-cysteine was active as substrates to a lesser extent than L-lysine . The amino-terminal amino acid sequence was determined to be Met-Asn-Ile-Phe-Ala-Ile-Leu . These properties were compared with those of other bacterial lysine decarboxylases. Can J Microbiol, 1991 Nov, 37(11), 840 - 7 Changes in rates of synthesis of individual proteins in a psychrophilic bacterium after a shift in temperature; Araki T; In the psychrophilic bacterium Vibrio sp . strain ANT-300, which has the ability to grow efficiently between 13 and -2 degrees C, with an optimum at 7 degrees C, cells in steady-state growth at 0 and 13 degrees C appeared to exhibit different patterns in the levels of certain individual proteins . With a shift in temperature, the steady-state level of individual proteins was achieved only after dramatic transient changes in the rates of synthesis of a small number of those proteins whose levels would be adjusted . Upon a shift up from 0 to 13 degrees C, the rates of synthesis of at least 25 proteins increased transiently, while increased rates of synthesis of 39 proteins were induced immediately upon a shift down from 13 to 0 degrees C . The proteins of which the levels would be adjusted were synthesized at differential rates, which varied conspicuously with respect to timing after the shifts in temperature . Such changes appear to be active regulatory responses to changes in temperature. J Clin Microbiol, 1991 Nov, 29(11), 2517 - 21 Polymerase chain reaction for detection of the cholera enterotoxin operon of Vibrio cholerae; Shirai H et al.; We report a set of oligonucleotide primers and amplification conditions for the polymerase chain reaction to detect the ctx operon of Vibrio cholerae . The results of this assay on strains of V . cholerae and related organisms were identical with those obtained by the DNA colony hybridization test with the polynucleotide probe . The detection limit of this system was 1 pg of chromosomal DNA or broth culture containing three viable cells . The polymerase chain reaction method could directly detect the ctx operon sequences in rice-water stool samples from patients with cholera. FEMS Microbiol Lett, 1991 Nov 1, 68(1), 113 - 7 Adherence of Vibrio parahaemolyticus to rabbit intestinal epithelial cells in vitro; Chakrabarti MK et al.; Kanagawa positive strains of Vibrio parahaemolyticus showed adherence whereas most of the Kanagawa negative strains were non-adhering to rabbit intestinal epithelial cells . Anti-hemolysin antisera did not inhibit the adherence of V . parahaemolyticus strains . Moreover, the adhesive capacity of non-adhering strains was not enhanced by purified hemolysin . Cell surface hydrophobicity remained the same in both Kanagawa positive and negative strains of V . parahaemolyticus . Fetuin strongly inhibited the adherence to rabbit intestinal epithelial cells followed by -mannose and D-glucose. Mol Gen Genet, 1991 Nov, 230(1-2), 251 - 6 Highly bioluminescent Bacillus subtilis obtained through high-level expression of a luxAB fusion gene; Jacobs M et al.; Bioluminescence levels comparable to those achievable in Escherichia coli have yet to be obtained from luxAB expression in gram-positive bacteria . In this communication we describe the gene engineering required to generate a highly bioluminescent derivative of Bacillus subtilis . The combination of a powerful promoter, Pxyn, a fusion derivative of luxAB from Vibrio harveyi and translational coupling have overcome the previously reported limitations in luxAB expression . The implications for highly bioluminescent gram-positive organisms are discussed. Mikrobiol Zh, 1991 Nov-Dec, 53(6), 94 - 8 {The use of a CHO cell culture in studying Vibrio cholerae grown under different conditions}; Sal'nikova OI et al.; Studies of biological activity of cholera vibrios in cultures of chinese hamster ovary cells (CHO) have revealed their strong dependence on culture conditions . Elongation of CHO cells is caused only by choleragenic strains . Under stationary conditions of culture the vibrios were found to release haemolisin into the medium and had a cytotoxic effect . Most of cytotoxic supernatants exhibited a neuraminidase activity . Proteolytic activity was less dependent on the vibrio culture conditions . Strains with a high proteolytic activity caused rounding of the CHO cells. Science, 1991 Nov 1, 254(5032), 710 - 3 An inducible bundle-forming pilus of enteropathogenic Escherichia coli; Giron JA et al.; Enteropathogenic Escherichia coli (EPEC), a cause of childhood diarrhea, grow on the surface of the small intestine and on cultured epithelial cells as colonies of adherent bacteria . When propagated on solid medium containing blood or attached to HEp-2 cells, EPEC express ropelike bundles of filaments, termed bundle-forming pili (BFP), that create a network of fibers that bind together the individual organisms . BFP were found to be expressed by five EPEC serogroups, each harboring a approximately 92-kilobase plasmid previously known to be important for virulence in humans . When two of these strains were cured of this plasmid, they neither expressed BFP nor grew as adherent colonies . An antiserum to BFP reduced the capacity of EPEC to infect cultured epithelial cells . BFP are composed of a repeating subunit of 19,500 daltons, the amino-terminal amino acid sequence of this subunit is homologous to that of the toxin-coregulated pilin of Vibrio cholerae. Biochemistry, 1991 Oct 29, 30(43), 10551 - 7 Mapping the polarity profiles of general anesthetic target sites using n-alkane-(alpha, omega)-diols; Moss GW et al.; The effects of the homologous series of n-alkane-(alpha, omega)-diols have been studied on the inhibition of the purified firefly luciferase enzyme from Photinus pyralis, the inhibition of the purified bacterial luciferase enzyme from Vibrio harveyi, and the induction of general anesthesia in Xenopus laevis tadpoles . All but one of the diols tested were found to be reversible general anesthetics . The diols inhibited firefly luciferase by competing with its normal substrate firefly luciferin, and they inhibited bacterial luciferase by competing with the substrate n-decanal . For all but the smallest agent (1,4-butanediol), only a single diol molecule was found to be involved in the inhibition of the enzymes . Inhibition constants Ki were determined for the enzymes, and general anesthetic EC50 concentrations were determined for tadpoles . These data were then used in conjunction with previously determined n-alkane and n-alcohol data to calculate, as a function of chain length, the incremental standard Gibbs free energies delta (delta G0) for adding apolar -CH2- groups and for converting apolar terminal -CH3 groups to polar -CH2OH groups . The resulting plots of delta (delta G0) versus chain length gave a consistent mapping of the polarity profiles of the anesthetic-binding pockets . They clearly reveal the existence of two substantial and distinct polar regions in the anesthetic-binding pocket of firefly luciferase but only one such region for bacterial luciferase and for the unknown target sites underlying general anesthesia . The polarities and geometric properties of these different binding sites for straight-chain anesthetics are discussed in terms of simple models. J Biol Chem, 1991 Oct 25, 266(30), 20094 - 102 Structural analysis and functional role of the carbohydrate component of somatostatin receptors; Rens-Domiano S et al.; SRIF receptors are membrane-bound glycoproteins . To structurally identify the carbohydrate components of SRIF receptors, solubilized rat brain SRIF receptors were subjected to lectin affinity chromatography . Solubilized SRIF receptors specifically bound to wheat germ agglutinin-lectin affinity columns but not to succinylated wheat germ agglutinin . This finding, as well as the ability of the solubilized receptor to interact with a Sambucus nigra L . lectin affinity column suggested that sialic acid residues are associated with SRIF receptors . The inability of the receptor to bind to concanavalin A, Dolichus biflorus agglutinin, Ulex europeaus I, and Jacalin lectin affinity columns suggests that high mannose, N-acetylgalactosamine, fucose, and O-linked carbohydrates are not associated with receptor . To investigate the functional role of the carbohydrate groups in brain SRIF receptors, specific sugars were selectively cleaved from SRIF receptors and the subsequent effect on the specific high affinity binding of the agonist {125I}MK 678 to SRIF receptors was determined . Treatment of the receptor with endoglycosidase D did not affect the specific binding of {125I} MK 678 to the solubilized SRIF receptors, consistent with the finding from lectin affinity chromatography that high mannose-type carbohydrate structures were not associated with SRIF receptors . Treatment of solubilized SRIF receptors with peptide-N-glycosidase F and endoglycosidases H and F reduced {125I}MK 678 binding to SRIF receptors indicating that either hybrid, or a combination of hybrid and complex N-linked carbohydrate structures, have a role in maintaining the receptor in a high affinity state for agonists . Treatment of solubilized SRIF receptors with neuraminidase from Vibrio cholera abolished high affinity agonist binding to the receptors, whereas treatment of the receptor with neuraminidase from Newcastle disease virus did not affect {125I}MK 678 binding to the receptor . These findings suggest that sialic acid residues in an alpha 2,6-configuration have a role in maintaining the SRIF receptor in a high affinity conformation for agonists . This is further indicated by studies on SRIF receptors in the pituitary tumor cell line, AtT-20 . Treatment of AtT-20 cells in culture with neuraminidase (V . cholera) greatly reduces high affinity {125I} MK 678 binding sites, but did not alter the maximal ability of SRIF to inhibit forskolin-stimulated cAMP accumulation in intact AtT-20 cells . This finding suggests that the desialylated SRIF receptor is functionally active and remains coupled to GTP-binding proteins, but exhibits a reduced affinity for agonists . Treatment of AtT-20 cell membranes with neuraminidase from V . cholera was also able to greatly reduce the affinity of SRIF receptors for {125I}MK 678.(ABSTRACT TRUNCATED AT 400 WORDS) J Vet Med Sci, 1991 Oct, 53(5), 883 - 7 Plasma-dependent chemotactic activity of hemocytes derived from a juvenile estuarine gastropod mollusc, Clithon retropictus, to Vibrio parahaemolyticus and Escherichia coli strains; Kumazawa NH et al.; Hemocytes of adult Clithon retropictus were attracted chemotactically to live Vibrio parahaemolyticus and Escherichia coli strains . The chemotaxis was stimulated by the plasma of adult C . retropictus . Hemocytes of the juvenile specimen were attracted chemotactically to V . parahaemolyticus and E . coli strains in the presence of the plasma of the juvenile and only to E . coli strain in the absence of the plasma . These evidences suggest that hemocytes of juvenile C . retropictus might be defective to recognize V . parahaemolyticus strains and that the hemocytes would display full activities in the presence of the plasma factor(s). Mol Microbiol, 1991 Oct, 5(10), 2547 - 55 Distinguishing between the extracellular DNases of Vibrio cholerae and development of a transformation system; Focareta T et al.; Vibrio cholerae is known to secrete DNase(s) into the extracellular environment . These proteins have been thought to be responsible for the difficulties in transforming this organism . In this work we demonstrate that the dns and xds genes differ and that their products are solely responsible for the extracellular DNase activity . By site-directed mutagenesis, strains have been constructed which are mutant in one or both genes . These strains have been assessed for their ability to be transformed with plasmid DNA and for their virulence in the infant mouse cholera model . DNase-deficient mutants can be readily transformed and the product of dns appears to be the more significant barrier . No effect on virulence was observed with the mutants. West J Med, 1991 Oct, 155(4), 400 - 3 Vibrio vulnificus . Hazard on the half shell; Koenig KL et al.; Vibrio vulnificus is an extremely invasive gram-negative bacillus that causes bacteremia and shock . It should be suspected in any patient who is immunocompromised or has liver disease or hemochromatosis . Reduced gastric acidity may also increase the risk of infection if a patient presents with a history of ingesting raw shellfish (especially oysters) or trauma in brackish waters and skin lesions . Patients most commonly present with one of three clinical syndromes: primary septicemia, wound infection, or gastroenteritis . Treatment includes aggressive wound debridement, antibiotic therapy, and supportive care . Rapidly diagnosing and promptly initiating therapy are critical because V vulnificus infection is rapidly progressive and mortality approaches 100% if septic shock occurs. Am J Vet Res, 1991 Oct, 52(10), 1658 - 64 Effect of endocytic and metabolic inhibitors on the internalization and intracellular growth of Brucella abortus in Vero cells; Detilleux PG et al.; Uptake, transfer to rough endoplasmic reticulum, and intracellular growth of Brucella abortus were studied in Vero cells treated with endocytic and metabolic inhibitors . Infection of Vero cells was suppressed when inhibitors of energy metabolism (iodoacetate, dinitrophenol), receptor-mediated endocytosis (monodansylcadaverine, amantadine, methylamine), or endosomal acidification (chloroquine, ammonium chloride, monensin) were added to the inoculum . Inhibition was not observed when these drugs were added after the inoculation period . Infection of Vero cells by B abortus was inhibited by dibutyryl-cyclic adenosine monophosphate and Vibrio cholerae enterotoxin, but was stimulated by dibutyryl-cyclic guanosine monophosphate and escherichia coli heat-stable enterotoxin a . Uptake of B abortus by Vero cells was not prevented by colchicine, but was abolished by cytochalasin B . Uptake of heat-killed B abortus and noninvasive E coli was similar to that of viable brucellae . Intracellular growth of B abortus was not affected by cycloheximide . Results indicate that: B abortus may be internalized by a receptor-mediated phagocytic process; transfer of B abortus from phagosomes to rough endoplasmic reticulum may require endosomal acidification; and replication of B abortus within the rough endoplasmic reticulum may not depend on protein synthesis by the host cell. J Wildl Dis, 1991 Oct, 27(4), 706 - 9 Nasitrema sp.-associated encephalitis in a striped dolphin (Stenella coeruleoalba) stranded in the Gulf of Mexico; O'Shea TJ et al.; An immature female striped dolphin (Stenella coeruleoalba) found dead on a northwestern Florida beach in 1988 exhibited severe inflammation bilaterally in the dorsal and mid-thalamus in association with adult trematodes (Nasitrema sp.) and trematode eggs . Numerous specimens of Nasitrema sp . also were present in the pterygoid sinuses . Pneumonia in association with a heavy growth of Vibrio damsela was observed also . This report confirms the occurrence of Nasitrema sp.-associated encephalitis in striped dolphins and in small cetaceans from the Gulf of Mexico. Zentralbl Bakteriol, 1991 Oct, 275(4), 467 - 73 A polyclonal-monoclonal antibody based sensitive sandwich enzyme linked immunosorbent assay for specific detection of cholera toxin; Bhadra RK et al.; A sensitive sandwich enzyme-linked immunosorbent assay (ELISA) for specific detection of prototype cholera toxin (CT) elaborated by Vibrio cholerae serovar O1 has been developed . The use of a high affinity monoclonal antibody (MAb) for capturing of CT epitopes permitted a high efficiency . Using this ELISA, we sought in vitro production of CT from clinical strains of V . cholerae O1, Non-O1 and from LT-producing E . coli . All culture supernatants of V . cholerae O1 were positive for CT whereas V . cholerae non-O1 and LT producing E . coli were found negative for CT . This ELISA will be particularly useful in specifically designed studies where detection of CT and not of related labile toxins is mandatory. J Biochem (Tokyo), 1991 Oct, 110(4), 548 - 52 Alpha-macroglobulin-like plasma inactivator for Vibrio vulnificus metalloprotease; Miyoshi S et al.; The metalloprotease produced by Vibrio vulnificus (VVP) is known to be quickly inactivated by plasma proteins which belong to the class of alpha-macroglobulins in vitro at a molar ratio of 1:1 . But the in vivo potential of the inactivators has not been studied . Macroalbumin (MA), a member of alpha-macroglobulins in guinea pig plasma, was found to inactivate VVP by means of physical entrapment in vitro . In vivo actions of VVP, permeability-enhancing and hemorrhagic actions, were greatly augmented by simultaneous injection of the antibody against MA, which had no effect on in vitro proteolytic action toward azocasein . The interstitial-tissue space in the normal guinea pig skin contains a negligible amount of MA . However, sufficient MA was present in the extravascular fluid collected after the intradermal injection of VVP . Besides, in the extravascular fluid, VVP formed a complex with MA and no inactivator other than MA was found . These results indicate that plasma MA leaked from the vascular system owing to the permeability-enhancing and hemorrhagic actions of VVP, resulting in inactivation of VVP in situ. Genes Dev, 1991 Oct, 5(10), 1834 - 46 Processing of TCP pilin by TcpJ typifies a common step intrinsic to a newly recognized pathway of extracellular protein secretion by gram-negative bacteria; Kaufman MR et al.; Biogenesis of the Vibrio cholerae toxin-coregulated pilus (TCP) requires the activities of at least seven accessory proteins . We demonstrate that a portion of this pathway involves a novel processing step in which a hydrophilic leader peptide is proteolytically removed from TcpA by the gene product characterized in this report, TcpJ, to yield the mature, export-competent form of the pilin . Cleavage of the pilin leader peptide is independent of known signal peptidases as demonstrated by pilin-processing profiles in Escherichia coli strains conditionally defective for production of leader peptidase or grown in the presence of the antibiotic globomycin . Additionally, pilin cleavage did not rely on the SecA protein, as evidenced by TcpA processing in azide-treated cells . These results suggest that TcpJ is representative of a new class of proteins involved in SecA-independent proteolytic cleavage of a set of atypical leader peptides during extracellular export. J Biolumin Chemilumin, 1991 Oct-Dec, 6(4), 251 - 8 Amplified luminometric assays of alkaline phosphatase using riboflavin phosphates; Harbron S et al.; An assay for alkaline phosphatase is described which is based on the hydrolysis of riboflavin phosphates (5'FMN or 4'FMN) to produce riboflavin . This is converted to 5'FMN using riboflavin kinase, and then assayed using the bacterial bioluminescent system from Vibrio harveyi or V . fischeri . The most sensitive assay is obtained using 4'FMN, which can measure less than 20 amol after a 1-hour incubation. Biochem Biophys Res Commun, 1991 Sep 30, 179(3), 1200 - 4 T7 infection-dependent selective expression of cloned genes in P1-lysogenic Escherichia coli; Olenik C et al.; Expression systems based on the selective transcription of genes cloned behind a T7 promoter, by T7 RNA polymerase, display a non-negligible basal expression when the T7 RNA polymerase gene is present within the host organism before induction of the system . This is a problem, especially for cloning and controlled expression of genes toxic to the host organism . We have circumvented this problem by taking advantage of abortive T7 infection of E . coli (P1), in the course of which T7 RNA polymerase is synthesized but bacterial growth is not quantitatively impaired . We have tested this system with three reporter genes, the 6-phospho-beta-galactosidase gene of Staphylococcus aureus, the luciferase operon of Vibrio harveyi, and the rabbit beta-globin gene; we have found very low basal levels, while, upon T7 infection, transcription is at least as efficient as in other in vivo T7 RNA polymerase systems in use. Eur J Biochem, 1991 Sep 15, 200(3), 689 - 98 Chemical structure of the carbohydrate backbone of Vibrio parahaemolyticus serotype 012 lipopolysaccharide; Kondo S et al.; The chemical structure of the saccharide portion of Vibrio parahaemolyticus serotype 012 lipopolysaccharide was studied . Using chemical degradation and modification, as well as methylation analysis in combination with GLC-MS, laser-desorption mass spectrometry and 1H-NMR and 13C-NMR spectroscopy, the carbohydrate backbone of the lipopolysaccharide was characterized as a branched decasaccharide with the following structure: (formula; see text) In the native lipopolysaccharide two additional phosphate groups are present and 3-deoxy-D-threo-hexulosonic acid and D-galacturonic acid are bound via acid-labile linkages. Biochim Biophys Acta, 1991 Sep 13, 1059(3), 332 - 8 A novel mechanism of cation/substrate cotransport: Na+/H+/adenosine cotransport in Vibrio parahaemolyticus; Okabe Y et al.; Adenosine is actively transported with Na+ in Vibrio parahaemolyticus (Sakai, Y., Tsuda, M., Tsuchiya, T . (1987) Biochim, Biophys . Acta 893, 43-48) . The proton conductor carbonylcyanide m-chlorophenylhydrazone, CCCP, strongly inhibited active transport of adenosine at pH 8.5 as well as at pH 7.0 . This seemed peculiar because the driving force, an electrochemical potential of Na+, is established by the Na(+)-extruding respiratory chain at pH 8.5 in this organism, although it is established by the function of the Na+/H+ antiporter at pH 7.0 . This suggested that H+ might be involved in the adenosine transport . We detected H+ uptake induced by adenosine influx in V . parahaemolyticus cells in the presence of Na+, but not in its absence, suggesting the occurrence of Na+/H+/adenosine cotransport . We isolated formycin A-resistant mutants which showed defective adenosine transport . The mutation resulted in simultaneous losses of Na+ uptake and H+ uptake induced by adenosine . In revertants from these mutants the Na+ uptake and H+ uptake were restored simultaneously . The frequencies of reversion were in the order of 10(-7), indicating that the mutations were single mutations; namely that Na+/adenosine cotransport and H+/adenosine cotransport took place via the same carrier . Thus, we conclude that adenosine is transported by the novel mechanism of Na+/H+/adenosine cotransport in V . parahaemolyticus. Carbohydr Res, 1991 Sep 2, 216, 61 - 6 2,3-Didehydro-2-deoxysialic acids structurally varied at C-5 and their behaviour towards the sialidase from Vibrio cholerae; Schreiner E et al.; 2,3-Didehydro-2-deoxy-N-trifluoroacetylneuraminic acid (5-trifluoroacetyl-Neu2en) (3) has been synthesised from Neu5Ac2en (1) by hydrazinolysis, to give Neu2en (2), followed by N-trifluoroacetylation . 2,3-Didehydro-2,3-dideoxy-D-glycero-D-galacto-2-nonulopyranoson ic acid (Kdn2en, 8) and 5-azido-2,3-didehydro-2,3,5-trideoxy-D-glycero-D-galacto-2-nonu lopyranosonic acid (5-azido-5-deoxy-Kdn2en, 9) have been prepared from the acetylated methyl esters of Kdn (4) and 5-azido-5-deoxy-Kdn (5) via Zemplen saponification . The behaviour of the above 2,3-didehydro-2-deoxysialic acids towards Vibrio cholerae sialidase has been investigated. Antimicrob Agents Chemother, 1991 Sep, 35(9), 1864 - 7 Efficacy of a single dose of furazolidone for treatment of cholera in children; Rabbani GH et al.; To test the efficacy and safety of furazolidone given as a single dose for childhood cholera, a randomized double-blind placebo-controlled trial was carried out among 118 culture-positive dehydrated children with diarrhea . Patients were randomly assigned to one of four groups to receive medication orally in liquid suspension: furazolidone at 7 mg/kg/day once, furazolidone at 7 mg/kg/day divided into four doses for 3 days, placebo once, or placebo for 3 days . After 12 patients with furazolidone-resistant infections were excluded from the analysis of efficacy, it was determined that both groups treated with furazolidone showed significantly higher rates of bacteriologic success (stool cultures negative for Vibrio cholerae on days 2 to 4 after start of therapy) and clinical success (cessation of diarrhea within 72 h after start of therapy) than corresponding placebo groups (P less than 0.001) . There were no significant differences between responses to the 3-day and single-dose regimens of furazolidone, but there was a trend toward better clinical responses in patients who received furazolidone for 3 days . No patient treated with furazolidone dropped out because of side effects . These results indicate that furazolidone, given as either a single dose or divided doses for 3 days, is effective treatment for childhood cholera. J Neurochem, 1991 Sep, 57(3), 748 - 53 Evidence for nonrandom distribution of GD1a ganglioside in rabbit brain microsomal membranes; Palestini P et al.; GD1a is the major ganglioside of rabbit brain microsomal membranes and occurs mainly with two molecular species, containing the C18:1 (62.3%) and C20:1 (37.7%) long-chain bases . The membranes were exposed to Vibrio cholerae (VC) sialidase under conditions where the enzyme hydrolyzed only GD1a (approximately 9%), producing GM1 ganglioside, whereas the other gangliosides remained virtually unaffected . The long-chain-base analysis showed that newly-formed GM1 contained approximately 68% of the C20:1 molecular species . This indicates that VC sialidase did not randomly affect the two molecular species of GD1a but hydrolyzed preferentially the C20:1 one . In similar experiments, GD1a was inserted into the external layer of phosphatidylcholine vesicles and incubated with VC sialidase under conditions producing approximately 10% hydrolysis . Long-chain-base analysis showed that the proportion of C20:1 species in GM1 was 25.1% using vesicles composed of dipalmitoylphosphatidylcholine and 42.3% with egg phosphatidylcholine, whereas it was 39.2% in the starting GD1a . Therefore, in artificial membranes, VC sialidase acted preferentially on the C18:1 or C20:1 molecular species, depending on the length and unsaturation of the phospholipid fatty acids . Because VC sialidase is known to affect molecular dispersions more easily than packed aggregations of the gangliosidic substrate, the data suggest that in rabbit brain microsomal membranes the GD1a ganglioside molecular species carrying C20:1 long-chain base are more molecularly dispersed than those containing C18:1 long-chain base. Appl Environ Microbiol, 1991 Sep, 57(9), 2750 - 7 Characterization of Vibrio anguillarum and closely related species isolated from farmed fish in Norway; Myhr E et al.; A total of 264 bacterial strains tentatively or definitely classified as Vibrio anguillarum were examined . The strains were isolated from diseased or healthy Norwegian fish after routine autopsy . With the exception of five isolates from wild saithe (Pollachius virens), the strains originated from nine different species of farmed fish . The bacteria were subjected to morphological, physiological, and biochemical studies, numerical taxonomical analyses, serotyping by slide agglutination and enzyme-linked immunosorbent assay, DNA-plasmid profiling, and in vitro antimicrobial drug susceptibility testing . The results of the microbiological studies were correlated to anamnestic information . The bacterial strains were identified as V . anguillarum serovar O1 (n = 132), serovar O2 (n = 89), serovar O4 (n = 2), serovar O8 (n = 1), and not typeable (n = 1) as well as Vibrio splendidus biovar I (n = 36) and biovar II (n = 1), Vibrio tubiashii (n = 1), and Vibrio fischerii (n = 1) . V . anguillarum serovar O1 or O2 was isolated in 176 out of 179 cases of clinical vibriosis in Atlantic salmon (Salmo salar) . V . anguillarum serovar O1 was the only serovar isolated from salmonid fish species other than Atlantic salmon, while V . anguillarum serovar O2 was isolated from all marine fish suffering from vibriosis . A 48-Mda plasmid was isolated from all V . anguillarum serovar O1 isolates examined . Serovar O2 isolates did not harbor any plasmids . Resistance against commonly used antibiotic compounds was not demonstrated among V . anguillarum isolates . Neither V . splendidus biovar I nor other V . anguillarum-related species appeared to be of clinical importance among salmonid fish.(ABSTRACT TRUNCATED AT 250 WORDS) Appl Environ Microbiol, 1991 Sep, 57(9), 2651 - 5 Use of the polymerase chain reaction in detection of culturable and nonculturable Vibrio vulnificus cells; Brauns LA et al.; Vibrio vulnificus is a human pathogen associated with consumption of raw oysters . During the colder months the organism apparently enters a viable but nonculturable state and thus cannot be cultured by ordinary bacteriological methods . For this reason, another means of detecting this bacterium is necessary . In the present study we utilized the polymerase chain reaction (PCR) to detect V . vulnificus DNA, thus eliminating the problem of nonculturability . DNA from both culturable and nonculturable cells of V . vulnificus was amplified by PCR with primers flanking a 340-bp fragment of the cytotoxin-hemolysin gene . As little as 72 pg of DNA from culturable cells and 31 ng of DNA from nonculturable cells could be detected . Fifty cycles of a two-step reaction (30 s {each} at 94 and 65 degrees C) were found to be optimal as well as more time efficient than the three-step PCR . The total procedure from the point of DNA extraction to observation on a gel required less than 8 h . Possible reasons for the difficulties encountered in amplifying DNA from nonculturable cells, e.g., gene rearrangement or loss of the hemolysin gene, are discussed. Appl Environ Microbiol, 1991 Sep, 57(9), 2640 - 4 Formation of nonculturable Vibrio vulnificus cells and its relationship to the starvation state; Oliver JD et al.; Entry into the viable but nonculturable state by the human bacterial pathogen Vibrio vulnificus in artificial seawater microcosms was studied . In contrast to the long-term culturability exhibited by cells incubated under these starvation conditions at room temperature, cells exposed to a temperature downshift to 5 degrees C exhibited an immediate decrease in culturability . Cells incubated at low temperature exhibited a morphological change from rods to cocci but demonstrated no reductive division . Of 10 factors studied which might affect the nonculturable response in V . vulnificus, only the physiological age of the cells was found to significantly affect the rate at which cells became nonculturable . The nonculturable response appears to be related to the starvation response, as prestarvation at room temperature for 24 h was found to eliminate the nonculturable response of cells subsequently incubated at 5 degrees C . This observation suggests that the synthesis of starvation proteins may repress the viable but nonculturable program displayed during low-temperature incubation . The possible ecological significance of these findings is discussed. Microb Pathog, 1991 Sep, 11(3), 179 - 88 Epitope differences in toxin-coregulated pili produced by classical and El Tor Vibrio cholerae O1; Jonson G et al.; A toxin-coregulated pilus (TCP), that is important for intestinal colonization of Vibrio cholerae O1, may be produced by vibrios of both classical and EI Tor biotypes . By comparing TCP produced by various strains of the two biotypes in immunoblotting and enzyme-linked immunosorbent assays (ELISA) using monoclonal antibodies (mAbs) and polyclonal antisera against TCP from classical vibrios, we have found biotype-related epitope differences in TCP . Our results indicate that TCP of classical strains has an epitope in the TcpA-subunit (20.5 kDa) that is missing in EI Tor TcpA, and an additional epitope that is more strongly expressed in classical TcpA . A polyclonal antiserum reacted strongly with TcpA from strains of both biotypes in immunoblotting suggesting both the presence of major shared TcpA epitopes and that the low or absent reactivity of EI Tor TcpA with the mAbs was not due to lower production of TcpA by EI Tor strains . Whereas all the TcpA-positive classical strains inhibited the binding of polyclonal antiserum and mAbs to solid phase-bound TCP-positive bacteria in an inhibition ELISA, practically no inhibition was observed with TcpA-positive EI Tor strains . This together with findings in immunoelectron microscopy studies that TCP 'bundles' were only detected on classical strains, suggest that TCP is poorly expressed on EI Tor vibrios. Vopr Med Khim, 1991 Sep-Oct, 37(5), 28 - 31 {Catalytic properties of neuraminidase of non-cholera vibrios}; Lavrovskii SN et al.; Main catalytic properties of commercially available neuraminidase preparations from noncholeric vibrios were studied . The enzymatic activity was measured using a simple resorcinol procedure . Optimal conditions for neuraminidase effect: pH 5.5-6.0 and buffer composition, were characterized . Affinity of the enzyme to various substrates was studied using 10 natural and synthetic sialoconjugates . Km values were studied for fetuin, ovomucin and transferrin used as optimal substrates . When influence of meta ions, detergents, complexes and other compounds was studied, activation of neuraminidase was found in presence of bivalent metal ions, especially of Ca2+, while chelate-forming complexes and heavy metal salts inhibited the enzyme . These results may be used in studies of the neuraminidase action mechanism and regulation of its activity. Bioessays, 1991 Sep, 13(9), 463 - 8 Na(+)-coupled alternative to H(+)-coupled primary transport systems in bacteria; Dimroth P; Protons are the most common coupling ions in bacterial energy conversions . However, while many organisms, such as the alkaliphilic Bacilli, employ H(+)-bioenergetics for electron transport phosphorylation, they use Na+ as the coupling ion for transport and flagellar movement . The Na+ gradient required for these bioenergetic functions is established by the secondary Na+/H+ antiporter . In contrast, Vibrio alginolyticus and methanogenic bacteria have primary pumps for both H+ and Na+ . They use the proton gradient for ATP synthesis while other, less energy-consuming membrane reactions are powered by the Na+ gradient . In a third mode, some anaerobic bacteria possess decarboxylases acting as primary Na+ pumps . For instance, in Klebsiella pneumoniae, the Na+ gradient established by oxaloacetate decarboxylase is used for the uptake of the growth substrate citrate, and Propionigenium modestum consumes the energy of the Na+ gradient formed by methylmalonyl-CoA decarboxylase directly for ATP synthesis. Zhonghua Yi Xue Za Zhi (Taipei), 1991 Sep, 48(3), 232 - 6 Non-0:1 Vibrio cholerae bacteremia: a case report and literature review; Wang K et al.; We reported a case of non-0:1 group Vibrio cholerae septicemia with myelodysplatic syndrome in Taiwan . We also reviewed the other 22 reported cases of non-0:1 Vibrion cholerae septicemia found in the literature regarding its pathogenesis and treatment . The case mortality rate of these 23 cases was 47.8% . Most of them had immunocompromised diseases, particularly liver cirrhosis and hematologic malignancy . Therefore, the most important factor is the host defense . The cholera-like enterotoxin and E1-Tor-like hemolysin also play a major role, but whether the gall bladder plays a role in organ growth is still unclear . The incidence of gastroenteritis is not well understood because of the low incidence of non-0:1 V . cholerae gastroenteritis as compared with other factors such as shell-fish eating . Ampicillin as the sole antibiotic for non-0:1 V . cholerae is not efficacious . Tetracyclines or chloramphenicol is more effective for treatment. Infect Immun, 1991 Sep, 59(9), 3046 - 52 Regulation of leukotriene B4 generation from human polymorphonuclear granulocytes after stimulation with formyl-methionyl-leucyl phenylalanine: effects of pertussis and cholera toxins; Hensler T et al.; The effects of holotoxins and toxin subunits from Bordetella pertussis and Vibrio cholerae strains on intact and digitonin-permeabilized human polymorphonuclear neutrophils were studied . Our data clearly demonstrate that formyl-methionyl-leucyl-phenylalanine (fMLP)-induced generation of chemotactic active leukotriene B4 was inhibited by both holotoxins as well as by their isolated enzymatic A protomers . In contrast, the respective binding components (B oligomers) did not affect leukotriene formation . Priming of digitonin-permeabilized neutrophils with either guanylylimidodiphosphate or inositol trisphosphate increased subsequent stimulation with fMLP . In contrast, diacylglycerol decreased fMLP-induced leukotriene B4 formation, but inositol trisphosphate and diacylglycerol had no effect on inhibition mediated by the toxins . In addition, pertussis and cholera toxins reduced the specific binding of {3H}fMLP . Scatchard plot analysis revealed that the observed decrease of peptide binding was due to a reduced number of receptor sites . The fMLP-stimulated {3H}guanylylimidodiphosphate binding and GTPase activity used as parameters for the activation of G proteins were decreased in parallel . These results suggest altered chemotactic receptor numbers and G-protein functions responsible for the toxin-dependent suppression of fMLP-mediated response for neutrophils. Gene, 1991 Aug 30, 105(1), 107 - 11 Transformation of Vibrio cholerae by plasmid DNA; Panda DK et al.; The lack of an efficient transformation system in Vibrio cholerae was a handicap in the genetic manipulation of this important human pathogen . Since V . cholerae cells secrete DNases, this may interfere with the uptake of DNA . The present report describes the approaches taken for transforming V . cholerae cells with plasmid DNA, by overcoming this DNase barrier . The partial success of transforming DNase-negative mutants confirmed the role of DNase in the nontransformability of the wild-type cells . Successful transformation was carried out following removal of DNases from the periplasmic space . This was achieved by treating the cells with Mg2+ and Ca2+ ions to allow the DNase to be released, and then holding them under conditions where the remaining DNase activity was minimized before adding DNA to the competent cells . Transformation efficiencies of the order of 10(-5) per recipient cell were observed. Biochem Biophys Res Commun, 1991 Aug 30, 179(1), 224 - 8 Na(+)-coupled ATP synthesis in a mutant of Vibrio parahaemolyticus lacking H(+)-translocating ATPase activity; Sakai-Tomita Y et al.; An H(+)-translocating ATPase-defective mutant of Vibrio parahaemolyticus YS-1 grew well on lactate as a sole source of carbon at pH 8.5 under aerobic conditions, but not under anaerobic conditions . Both wild type cells and the mutant cells could grow on lactate at pH 8.5 even in the presence of an H+ conductor, carbonylcyanide m-chlorophenylhydrazone (CCCP), but not at pH 7.5 . Oxidative phosphorylation resistant to CCCP in the mutant occurred at pH 8.5 . These findings suggest the existence of Na(+)-coupled oxidative phosphorylation which is functional at alkaline pHs in V . parahaemolyticus . In fact, we observed ATP synthesis driven by an artificially imposed Na+ gradient in YS-1 cells, which was resistant to CCCP. Biochim Biophys Acta, 1991 Aug 27, 1090(1), 139 - 41 Nucleotide sequence analysis of the CT operon of the Vibrio cholerae classical strain 569B; Dams E et al.; The complete nucleotide sequence of the Vibrio cholerae classical strain 569B was determined . The results prove the exactness of the amino acid CT B sequence published by Takao et al . (1985, Eur . J . Biochem . 146, 503-508) . A comparison is made with already reported CT genes. Carbohydr Res, 1991 Aug 20, 215(2), 303 - 14 Structural studies of the Vibrio cholerae O:3 O-antigen polysaccharide; Chowdhury TA et al.; The structure of the Vibrio cholerae O:3 O-antigen polysaccharide has been investigated, mainly by n.m.r . spectroscopy, mass spectrometry, sugar and methylation analysis, and specific degradations, and is proposed to involve the following tetrasaccharide repeating-unit . {formula: see text} . In this structure, D-D-Hep is D-glycero-D-manno-heptose, Asc is 3,6-dideoxy-L-arabino-hexose (ascarylose), and Sug is 2,4-diamino-2,4,6-trideoxy-D-glucose (bacillosamine) in which N-2 is acetylated and N-4 is acylated with a 3,5-dihydroxyhexanoic acid . That the 2,4-diamino-2,4,6-trideoxy-D-glucose residue is linked through O-3 and not through one of the hydroxyl groups in the 3,5-dihydroxyhexanoyl group is indicated but not definitely proved . The configuration of the latter group has not been determined . The f.a.b.-mass spectrum of the methylated O-antigen indicates that the structure given above also represents the biological repeating-unit. Ugeskr Laeger, 1991 Aug 19, 153(34), 2361 - 2 {Vibrio vulnificus}; Andersen HK; A patient sustained a knife wound while cleaning eels and subsequently severe wound infection developed . Vibrio vulnificus was isolated from the wound and, on the basis of this, the main features of the epidemiology of the bacteria and the typical clinical pictures are reviewed. FEMS Microbiol Lett, 1991 Aug 15, 66(3), 279 - 85 Effect of lipopolysaccharide core synthesis mutations on the production of Vibrio cholerae O-antigen in Escherichia coli K-12; Morona R et al.; The rfb genes of Vibrio cholerae O1 (Ogawa serotype) were subcloned into a derivative of pBR322 . This plasmid was transformed into several Escherichia coli K-12 mutant strains which produce an incomplete lipopolysaccharide (LPS)-core-oligosaccharide region . The data indicate that the V . cholerae O-antigen is assembled onto the E . coli LPS and that at least two glucoses are needed in the core in order to achieve a high level of production . These data are consistent with the reported presence of glucose in the V . cholerae LPS-core-oligosaccharide region. Gastroenterology, 1991 Aug, 101(2), 319 - 24 Effects of Vibrio cholerae recombinant strains on rabbit ileum in vivo . Enterotoxin production and myoelectric activity; Lind CD et al.; Previous studies have identified the effects of Vibrio cholerae and its enterotoxin, choleragen (CT A+B+), on the myoelectric activity of rabbit ileal loops in vivo . The response was defined as the migrating action potential complex, the single ring contraction that propels luminal contents aborad . In this study the same rabbit model is used to assess whether migrating action potential complex activity or fluid output is induced by recombinant strains of V . cholerae that produce no subunit of cholera toxin (CT A-B-) or only by the inactive binding subunit (CT A-B+) . Three live strains were studied: El Tor wild-type N16961 (CT A+B+) and recombinant strains CVD106 (CT A-B+) and JBK70 (CT A-B-) . Controls received sterile culture broth . Migrating action potential complex frequency in animals inoculated with CT A+B+ was significantly increased compared with that in all other experimental groups (P less than 0.01) . Fluid output was also increased in animals inoculated with CT A+B+ compared with fluid output in all other groups (P less than 0.05) . Migrating action potential complex frequency and fluid output in rabbits given CT A-B+ or CT A-B- did not differ from activity in controls . How these recombinant strains induce diarrhea is unknown, but the mechanism may involve bacterial colonization or production of an unknown toxin. Can J Microbiol, 1991 Aug, 37(8), 618 - 23 Seasonal variation in presence of Vibrio salmonicida and total bacterial counts in Norwegian fish-farm water; Enger O et al.; Total bacterial counts and the number of the fish pathogenic bacterium Vibrio salmonicida have been studied in water samples collected twice a month in 12 Norwegian fish farms from October 1988 to June 1989 . Total counts were determined by staining with 4',6-diamidino-2-phenylindole followed by epifluorescence microscopy . Cells of V . salmonicida were enumerated with a fluorescent antibody technique using highly specific monoclonal antibodies . Despite the fact that no outbreak of cold-water vibriosis was reported, V . salmonicida was detected in all 12 farms, in numbers ranging from 12 to 43 bacteria/mL . The number of farms where V . salmonicida was detected was generally highest during the winter . Total bacterial counts in the water samples varied between 4 X 10(4) and 9 X 10(5) bacteria/mL and the lowest numbers occurred during the winter period . The total bacterial counts were comparable with counts in water uninfluenced by fish farming . On the basis of our results, and additional information available about cold-water vibriosis caused by the bacterium V . salmonicida, an asymptomatic carrier state of the disease is proposed. Kansenshogaku Zasshi, 1991 Aug, 65(8), 897 - 904 {Studies on the enteropathogenic mechanism of non-O1 Vibrio cholerae . IV . Role of hemolysin}; Gyobu Y et al.; The role of hemolysin in the enteropathogenic mechanism of non-O1 V . cholerae was experimentally investigated, in vitro and in vivo . Results are summarized as follows . 1) . A greater majority of enteropathogenic strains produced hemolysin in Eagle MEM medium supplemented with 10% calf serum and in the rabbit ileal loop, while most non-enteropathogenic strains did not under the same conditions . 2) . Non-enteropathogenic mutants derived from enteropathogenic parent strains produced much less hemolysin than that of parent strains . 3) . A significant inhibition of the fluid accumulation in the ligated rabbit ileal loop test with viable cells was noted in rabbit immunized with purified hemolysin . These results indicate that hemolysin is the most important toxin in the enteropathogenic mechanism of non-O1 V . cholerae. Epidemiol Infect, 1991 Aug, 107(1), 225 - 33 Genetic diversity among toxigenic and nontoxigenic Vibrio cholerae O1 isolated from the Western Hemisphere; Chen F et al.; Multilocus enzyme electrophoresis was used to examine genetic relationships among and between toxigenic and non-toxigenic isolates of Vibrio cholerae O1 obtained from patients and the environment in the US Gulf Coast and surrounding areas . A total of 23 toxigenic and 23 non-toxigenic strains were examined . All the toxigenic and 7 of the non-toxigenic strains had the same alleles at 16 enzyme loci, whereas the balance of the nontoxigenic strains had 9 distinct combinations of alleles . This study suggests that all of the toxigenic strains belong to a single clone, and that while some of the non-toxigenic isolates were related, most were of diverse origin. Am J Epidemiol, 1991 Aug 1, 134(3), 290 - 7 The risk of Vibrio illness in the Florida raw oyster eating population, 1981-1988; Desenclos JC et al.; In the period 1981-1988, 333 cases of bacteriologically confirmed Vibrio illness were reported in Florida adult residents . A total of 197 patients (59.2%) had consumed raw oysters the week prior to becoming ill, and among those 197, 38 (19.3%) had a liver disease, 13 (6.6%) had past gastric surgery, and 15 (7.6%) were diabetic . To calculate a population-based incidence rate, the authors obtained prevalence estimates of annual raw oyster consumption, liver disease, previous gastric surgery, and diabetes through a random telephone survey of Florida adult residents and applied them to the January 1985 Florida population . The estimated age-standardized annual incidence of Vibrio illness per million was 95.4 for raw oyster eaters with liver disease, 9.2 for raw oyster eaters without liver disease, and 2.2 for non-raw oyster eaters . Those with prior gastric surgery had a moderately increased risk of Vibrio illness . The annual incidence for Vibrio septicemia was 82.8 for raw oyster eaters with liver disease, 2.0 for raw oyster eaters without liver disease, and 0.4 for non-raw oyster eaters . While estimates on which these data are based are subject to a number of potential biases, this is the first study to provide estimates of the risk of Vibrio illness in raw oyster eaters, and it supports the recommendation that raw oyster consumption should be avoided by persons with liver disease. Arch Intern Med, 1991 Aug, 151(8), 1606 - 9 Hemochromatosis, iron and septicemia caused by Vibrio vulnificus; Bullen JJ et al.; Vibrio vulnificus is killed by normal human blood but grows rapidly in blood from patients with hemochromatosis . It also grows in normal blood if the saturation of the transferrin is increased or if hematin, which contains iron, is added . It is suggested that the increased availability of iron in the blood of patients with chronic iron overload is responsible for their enhanced susceptibility to infection with V vulnificus. J Pharmacol Exp Ther, 1991 Aug, 258(2), 647 - 51 Purified choleragenoid does not induce migrating action potential complex activity in rabbit ileum in vivo; Lind CD et al.; The migrating action potential complex (MAPC), a single ring contraction that propels luminal contents abroad, is elicited by Vibrio cholerae and its enterotoxin, choleragen (A1A2B5), in rabbit ileal loops in vivo . Choleragenoid (B5; the binding subunit) was shown previously to induce MAPCs without activating the adenylate cyclase system and without stimulating fluid output . We restudied purified B5 (extracted by high-performance liquid chromatography) to assess its effects on the myoelectric activity of rabbit ileum: can MAPC activity can be induced without associated fluid production? Four different B5 preparations and two controls, V . cholerae and sterile saline, were used . MAPC activity and ileal fluid output were significantly increased in animals inoculated with A1A2B5 (V . cholerae-El Tor) compared with all other preparations and controls . Importantly, MAPC activity and fluid output in all B5 groups did not differ from those in saline controls, demonstrating that purified B5 does not induce MAPC activity in rabbit ilium in vivo . The previous study showing B5-induced MAPCs may have resulted from A1A2B5 contamination . These results suggest A1A2B5-induced adenylate cyclase activation; myoelectric activity may be interrelated with holotoxin binding that causes a neural response. J Bacteriol, 1991 Aug, 173(16), 5054 - 9 Resuscitation of Vibrio vulnificus from the viable but nonculturable state; Nilsson L et al.; Stationary-phase-grown cells of the estuarine bacterium Vibrio vulnificus became nonculturable in nutrient-limited artificial seawater microcosms after 27 days at 5 degrees C . When the nonculturable cells were subjected to temperature upshift by being placed at room temperature, the original bacterial numbers were detectable by plate counts after 3 days, with a corresponding increase in the direct viable counts from 3% to over 80% of the total cell count . No increase in the total cell count was observed during resuscitation, indicating that the plate count increases were not due to growth of a few culturable cells . Chloramphenicol and ampicillin totally inhibited resuscitation of the nonculturable cells when added to samples that had been at room temperature for up to 24 h . After 72 h of resuscitation, the inhibitors had an easily detectable but reduced effect on the resuscitated cells, indicating that protein and peptidoglycan synthesis were still ongoing . Major changes in the morphology of the cells were discovered . Nonculturable cells of V . vulnificus were small cocci (approximately 1.0 micron in diameter) . Upon resuscitation, the cells became large rods with a size of mid-log-phase cells (3.0 microns in length) . Four days after the cells had become fully resuscitated, the cell size had decreased to approximately 1.5 micron in length and 0.7 micron in width . The cells were able to go through at least two cycles of nonculturability and subsequent resuscitation without changes in the total cell count . This is the first report of resuscitation, without the addition of nutrient, of nonculturable cells, and it is suggested that temperature may be the determining factor in the resuscitation from this survival, or adaptation, state of certain species in estuarine environments. J Infect Dis, 1991 Aug, 164(2), 407 - 11 Antibody responses after immunization with killed oral cholera vaccines during the 1985 vaccine field trial in Bangladesh; Sack DA et al.; Sera collected during the 1985 oral cholera vaccine trial in Matlab, Bangladesh, which demonstrated efficacy of a whole cell combined with cholera B subunit vaccine (WC/BS) and a whole cell only vaccine (WC), were analyzed for antitoxin and vibriocidal antibodies . Before vaccines were given, antitoxin titers were highest in children, especially those with O blood group, whereas vibriocidal titers rose throughout life . Two weeks after three doses of vaccine, geometric mean antitoxin titers were 2.5-4.5 times higher in vaccinees who received the WC/BS vaccine; the vibriocidal titers were 1.3-2.1 times higher in vaccinees who received either vaccine . The titer elevations were relatively brief and were barely detectable 7 months after the third dose even though significant levels of protection persisted greater than or equal to 3 years . Thus, the oral vaccines induced a serum response in this large field trial that was similar to that seen in earlier pilot studies, but the duration of the serum responses was much shorter than the duration of the protection. Infect Immun, 1991 Aug, 59(8), 2727 - 36 Roles of motility and flagellar structure in pathogenicity of Vibrio cholerae: analysis of motility mutants in three animal models; Richardson K; Wild-type Vibrio cholerae of both El Tor and classical biotypes (strains N16961 and 395, respectively) and nonmotile mutant derivatives with and without flagellar structures were characterized in three different animal models: (i) the rabbit ileal loop, (ii) the removable intestinal tie adult rabbit diarrhea (RITARD) model, and (iii) the suckling mouse model . Both the wild-type strains and nonmotile mutants were toxinogenic in the rabbit ileal loop and the suckling mouse models . However, all of the nonmotile mutants produced significantly less fluid accumulation than did the wild-type parental strains . The two nonmotile mutants of strain N16961 did not adhere to rabbit ileal mucosa, but both nonmotile mutants derived from strain 395 exhibited adherence . In the RITARD model, the motile El Tor strains were more virulent than both the flagellate and aflagellate nonmotile mutants (all infected rabbits died within 18 h), while the nonmotile mutants, when fatalities occurred, required 78 to 105 h to produce a fatal outcome . Likewise, the motile classical parent 395 produced a fatal outcome within ca . 25 h, while nonmotile mutants required 69 to 96 h . The nonmotile flagellate strain KR31 was not significantly more virulent than the nonmotile aflagellate strain KR26 . Of the two classical nonmotile mutants, KR1, which produces a coreless sheathlike structure, was clearly more virulent (5 of 10 rabbits died within 96 h), while KR3 (nonmotile, aflagellate) did not produce fatalities in any of the 10 rabbits tested . Similarly, no significant difference in diarrheagenicity or colonizing ability was detected between the two nonmotile mutants derived from the El Tor strain, but the classical nonmotile mutant with the coreless sheath caused significantly greater diarrhea and colonized for a longer time than did the isogenic nonmotile aflagellate strain, KR3 . No significant differences between the nonmotile mutants were detected in competition studies done with suckling mice . Analysis of the wild-type and mutant strains in these three animal models clearly demonstrated a role for motility in V . cholerae pathogenicity, while analysis of only the nonmotile mutants derived from the classical parent suggested a role for flagellar structures. Vaccine, 1991 Aug, 9(8), 588 - 94 Amino-terminal domain of the El Tor haemolysin of Vibrio cholerae O1 is expressed in classical strains and is cytotoxic; Alm RA et al.; Previous studies have shown that the classical isolates of Vibrio cholerae possess an 11 bp deletion in the structural gene for the El Tor haemolysin leading to the production of a 27 kDa non-haemolytic truncated product HlyA* compared to the 82 kDa haemolysin, HlyA . These studies were designed to assess whether this truncated product had any biological activity . A KmR cartridge was introduced into the hlyA gene effectively eliminating the haemolysin . This was recombined into the chromosome of a variety of strains and isogenic pairs were examined in a number of systems . These studies suggest that the haemolytic (cytolytic) domain of HlyA resides at the C-terminus and that the N-terminus, which is conserved as HlyA* in classical strains, possesses enterotoxic (cytotoxic) activity . Experiments with the cholera-toxinless vaccine candidate JBK70 and its hlyA::KmR mutant suggest that HlyA* may be responsible for the residual diarrhoea observed in cholera-toxinless vaccine strains. Appl Environ Microbiol, 1991 Aug, 57(8), 2223 - 8 Isolation and characterization of turbot (Scophtalmus maximus)-associated bacteria with inhibitory effects against Vibrio anguillarum; Westerdahl A et al.; More than 400 isolates from the intestine and the external surface of farmed Scophtalmus maximus as well as from fish food and hatchery water were screened for inhibitory effects against the fish pathogen Vibrio anguillarum HI 11345 and seven other fish pathogens . The bacteria with inhibitory effects were then characterized with regard to their sites of colonization, especially the intestinal regions and sites within each region . Of the total number of bacterial isolates from the intestine, 28% were inhibitory against V . anguillarum HI 11345 . A marine biochemical assay was used to order the inhibitory strains into different phena . Most inhibitory bacteria were found in the rinse and mucus fractions of the gastrointestinal tract . No correlations among the different phena, site of colonization, and inhibitory effect could be found; however, a biochemical diversity was noted in the strains with an inhibitory effect . Of the isolates with an inhibitory effect against V . anguillarum HI 11345, 60% had an inhibitory effect on five other fish-pathogenic serotypes of V . anguillarum . Inhibitory effects of the isolates were also shown against Aeromonas salmonicida and Aeromonas hydrophila. Appl Environ Microbiol, 1991 Aug, 57(8), 2158 - 63 Occurrence of plasmids in Danish isolates of Vibrio anguillarum serovars O1 and O2 and association of plasmids with phenotypic characteristics; Larsen JL et al.; Two hundred and twenty-eight isolates of Vibrio anguillarum serovar O1 (125 isolates) and serovar O2 (103 isolates) have been characterized with regard to plasmid contents, biochemical properties, and in vitro hemagglutination and hydrophobic properties . Among 74 V . anguillarum isolates from diseased fish, 63 carried only a 67-kb plasmid (pJM1), 9 carried an additional 98-kb plasmid, and 1 isolate carried only the 98-kb plasmid . Only one isolate was without plasmids . In V . anguillarum serovar O1 from nondiseased fish (mucus and gills), plasmids of the same sizes were present in 29 isolates (58%), whereas 21 isolates (42%) were plasmid free . Based on hemagglutination and biochemical properties, V . anguillarum serovar O1 isolates were divided into eight biovars . The plasmid-carrying strains (102 isolates) all fell within biovars 1 and 2, whereas the 23 strains of biovars 3 to 8 were without plasmids . It was tentatively concluded there are two populations of V . anguillarum serovar O1 . One population contains plasmid(s), is hemagglutination negative and trehalose negative, and does not form pellicles in broth cultures, whereas the other population is plasmid free and has the opposite characteristics . The former group is the one related to disease in fish . All 20 V . anguillarum serovar O2 isolates from the environment were without plasmids, whereas 54 (65%) of the isolates from fish (trout and cod) carried plasmids . The biochemical diversity within serovar O2 was pronounced; 13 different biovars were demonstrated . No correlation between the presence of plasmids and biochemical properties was observed. Appl Environ Microbiol, 1991 Aug, 57(8), 2152 - 7 Cholera enterotoxin production in Vibrio cholerae O1 strains isolated from the environment and from humans in Japan; Minami A et al.; Vibrio cholerae O1 strains isolated from various sources in Japan over the years 1977 through 1987 were examined to confirm the presence or absence of the cholera enterotoxin (CT) gene and production of CT and to determine the kappa-phage type . The CT gene was detected in none of 225 isolates from natural waters but was present in all of the 10 isolates from environmental waters implicated in domestic cholera cases, in 64 strains (26.6%) of the 241 isolates from imported seafoods, in 43 strains (95.6%) of the 45 isolates from domestic cholera cases, and in 119 strains (93.7%) of the 127 isolates from imported cholera cases . The results suggest that the CT gene-positive strains of V . cholerae O1 have been imported into Japan through seafoods and/or by travelers . Sporadic cholera cases have resulted in contamination of the surrounding environment, but the CT gene-positive strains may not have persisted in natural waters to serve as a reservoir for epidemic cholera . The commercially available VET-RPLA kit (a latex agglutination kit for immunological detection of CT) detected production of CT in all of the CT gene-positive strains, indicating that there was no silent CT gene in the test strains . There was a strong correlation between the kappa-phage type and the presence or absence of the CT gene, suggesting a significant clonal difference between CT gene-positive and -negative strains . Five CT gene-negative strains isolated from imported cholera cases (travelers with mild diarrhea) induced a considerable amount of fluid accumulation in rabbit and/or suckling mouse intestines, indicating production of an enterotoxic factor(s) other than CT.(ABSTRACT TRUNCATED AT 250 WORDS) Mol Microbiol, 1991 Aug, 5(8), 2031 - 8 Transcription of the Vibrio cholerae haemolysin gene, hlyA, and cloning of a positive regulatory locus, hlyU; Williams SG et al.; Transcription of the Vibrio cholerae hlyA gene, which encodes a cytotoxic haemolysin, has been investigated . The hlyA transcript initiates 430 nucleotides (nt) upstream of the translational start site . hlyA-cat transcriptional fusion constructs were active in V . cholerae but not in Escherichia coli . An hlyA-cat fusion was used to select, from a V . cholerae O17 plasmid library, a clone that could activate the hlyA promoter in E . coli . This regulatory locus has been designated hlyU . hlyU appears to be distinct from the previously described hlyR locus. J Clin Microbiol, 1991 Aug, 29(8), 1684 - 8 Identification of Vibrio vulnificus O serovars with antilipopolysaccharide monoclonal antibody; Martin SJ et al.; A serotyping scheme for Vibrio vulnificus predicated on the detection of lipopolysaccharide (LPS) antigens is proposed . The serovar O typing scheme used to type V . vulnificus employs polyclonal antisera raised in rabbits immunized with heat-killed whole-cell vaccines . Polyclonal typing sera produced in this manner cross-react with heterologous strains . Affinity purification of polyclonal antisera with LPS affinity columns resolved some of these cross-reactions; however, affinity-purified polyclonal antisera still showed cross-reactions that were nonreciprocal . On the basis of the serological patterns that were obtained with affinity-purified polyclonal antisera, V . vulnificus strains were selected as vaccine strains for production of monoclonal antibody . Spleen cells harvested from BALB/c mice immunized with formalin-killed V . vulnificus cells were fused with SP2/O-Ag 14 myeloma cells . Hybridomas were screened by using LPS and whole-cell enzyme-linked immunosorbent assay to identify clones secreting LPS-specific antibodies . Monoclonal antibodies identified five LPS serological varieties of V . vulnificus and a single serovar each for Vibrio damsela and Vibrio hollisae . No cross-reactions between V . vulnificus and V . hollisae or V . damsela were observed. Antibiot Khimioter, 1991 Aug, 36(8), 37 - 9 {Antibiotic sensitivity of El Tor Vibrio cholerae after exposure to various pesticides and mineral fertilizers}; Ziiaev ShI et al.; The strains of El Tor Vibrio cholerae were exposed to different concentrations of pesticides (fazolone, treflane, prometrine, magnesium chlorate, omait and gardon) and mineral fertilizers (superphosphate, ammophos and carbamide) for 2 to 135 days . The subcultures of various ages were tested for their sensitivity to 16 antibiotics . The whole of 229 cultures were tested . There was a general tendency to lowering of the El Tor vibrio sensitivity to the majority of the antibiotics tested . The vibrio strains resistant to the antibiotics widely used in medical practice i . e . levomycetin, streptomycin, tetracycline, lincomycin, neomycin and kanamycin were isolated. J Neurosci, 1991 Aug, 11(8), 2443 - 52 Interaction of ganglioside GM1 with the B subunit of cholera toxin modulates growth and differentiation of neuroblastoma N18 cells; Masco D et al.; The present study uses the B subunit of cholera toxin, a protein that binds specifically to ganglioside GM1, to examine the role of endogenous GM1 in the process of growth and differentiation of mouse neuroblastoma N18 cells . Binding of the B subunit to neuroblastoma N18 cells inhibited DNA synthesis with concomitant induction of differentiation . The B subunit induced pronounced morphological changes: an increase in neurite outgrowth with branched neurites and spinelike processes . The distinct morphological alterations and neuritogenesis in response to the B subunit were also revealed by immunofluorescence with fluorescein-labeled B subunit . The mechanism of the B subunit-induced differentiation is different than that of spontaneous differentiation . Thrombin, a serine protease present in normal serum, inhibits neurite outgrowth induced by the removal of serum from the medium . In contrast, thrombin did not cause retraction of the neurites induced by the B subunit . Thus, thrombin or a thrombin-like protease is not involved in the process of neurite outgrowth mediated through endogenous GM1 . The biological effects of the B subunit are due to the binding of the B subunit to ganglioside GM1 and not due to changes in cAMP levels resulting from contaminating A subunit . We used highly purified cloned B subunit that cannot contain any A subunit because it was isolated from a Vibrio cholerae mutant that only expresses the B subunit . Neither the cloned nor commercial preparations of the B subunit induced increases of cAMP in these cells . There was a good correlation between the amount of B subunit bound to the cells and the biological effect . Finally, treatment with neuraminidase, which caused a fourfold increase in the level of membrane GM1 as determined by iodinated cholera toxin binding, enhanced the biological effect of the B subunit . However, neuraminidase treatment alone did not have significant effects, either on DNA synthesis or on morphology of the cells, indicating that elevations in the level of GM1 per se are not sufficient by themselves to cause significant changes in cell growth or differentiation . It seems most likely that the aggregation of endogenous GM1 on the cell surface by the B subunit is responsible for these effects on mouse neuroblastoma N18 cells. J Immunol, 1991 Aug 1, 147(3), 757 - 66 Cyclic AMP- and inositol phosphate-independent inhibition of Ca2+ influx by cholera toxin in CD3-stimulated Jurkat T cells . A study with a cholera toxin-resistant cell variant and the Ca2+ endoplasmic reticulum-ATPase inhibitor thapsigargin; Gouy H et al.; In this report, we describe a Jurkat cell variant, termed JCT8, the selection of which is based upon its resistance to cell-growth inhibition mediated by the holotoxin of Vibrio cholerae, cholera toxin (CT) . JCT8 cells exhibit normal cAMP production in response to various cAMP inducers, including CT, together with conserved ADP ribosylation in vitro of G-protein Gs alpha by the A subunit of the toxin . However, after a 4-h pretreatment with CT, JCT8 cells have a conserved expression of cell-surface CD3 molecules . These effects are in contrast to those elicited by the toxin in long term PGE2-desensitized Jurkat cells, which remain as sensitive as the wild type to the inhibitory action of CT on cell growth and CD3 cell-surface expression, despite poor responsiveness to CT with regard to cAMP production . In JCT8 cells, Ca2+ mobilization induced via the CD3/TCR is maintained after CT treatment contrasting with its complete suppression in the wild-type and in the PGE2-desensitized cells . However, as in the other cell types, CT still suppresses Ca2+ influx in JCT8 cells . Increase in inositol phosphates by CD3 stimulation of JCT8 cells, including of inositol 1,4,5-triphosphate (I(1,4,5)P3), is only partially antagonized by CT . This suggests either that in JCT8 cells there is a different susceptibility of Ca2+ mobilization and influx to partial inhibition by CT of CD3-triggered phospholipase C (PLC)-induced phosphoinositide hydrolysis or that an additional and PLC-independent suppressive effect of the toxin on Ca2+ influx may exist . To investigate this particular point further, we use Thapsigargin, a Ca(2+)-endoplasmic reticulum ATPase inhibitor that can mobilize in human T lymphocytes I(1,4,5)P3-dependent intracellular Ca2+ pools by a PLC-independent pathway . We demonstrate that the Ca2+ influx triggered in the wild-type Jurkat cells or in JCT8 cells by Thapsigargin is antagonized by CT . The present data are therefore consistent with the idea that CT specifically impairs in the Jurkat T cell model the entry of Ca2+ from extracellular spaces by a mechanism independent not only from cAMP but also in part from inhibition by the toxin of phosphoinositide hydrolysis. J Bacteriol, 1991 Aug, 173(16), 5036 - 46 Evidence for insertion sequence-mediated spread of the thermostable direct hemolysin gene among Vibrio species; Terai A et al.; The tdh gene of Vibrio parahaemolyticus which encodes the thermostable direct hemolysin has been found in some strains of other Vibrio species . Analysis of seven tdh genes cloned from V . parahaemolyticus, Vibrio mimicus, and non-O1 Vibrio cholerae revealed that all tdh genes were flanked by insertion sequence-like elements (collectively named ISVs) or related sequences derived from genetic rearrangement of ISVs . The ISVs possessed 18-bp terminal inverted repeats highly homologous to those of IS903 (2- to 4-bp mismatch) and were 881 to 1,058 bp long with less than 33.6% sequence divergence . These features and nucleotide sequence similarities among ISVs and IS903 (overall homologies between ISVs and IS903, ca . 50%) strongly suggest that they were derived from a common ancestral sequence . A family of ISVs were widely distributed in Vibrio species, often regardless of the possession of the tdh genes, and one to several copies of the ISVs per organism were detected . A strain of V . mimicus possessed two copies of the ISVs flanking the tdh gene and three copies unrelated to the tdh gene . However, the transposition activity of the ISVs could not be demonstrated, probably because they had suffered from base changes and insertions and deletions within the transposase gene . The possible mode of ISV-mediated spread of the tdh gene is discussed from an evolutionary standpoint. FEBS Lett, 1991 Jul 29, 286(1-2), 159 - 62 Identification and nucleotide sequence determination of the gene responsible for Ogawa serotype specificity of V . cholerae 01; Ito T et al.; The gene encoding a protein of 27 kDa, which is specifically expressed in Vibrio cholerae of serotype Ogawa, was identified and its nucleotide sequence determined . The plasmid carrying this gene was found to convert serotype specificity from Inaba to Ogawa when introduced into the Escherichia coli DH5(pVCI112) cell which harbors a cloned 20-kilobase genomic DNA fragment of V . cholerae NIH35A3 and expresses the 01 antigen of Inaba serotype. Gene, 1991 Jul 15, 103(1), 37 - 43 Analysis of two genes encoding heat-labile toxins and located on a single Ent plasmid from Escherichia coli; Murphy GL et al.; A clinical isolate of Escherichia coli harbored two copies of the heat-labile toxin (LT)-encoding gene (elt) on a 157-kb plasmid . The arrangement of the gene copies is different from the cholera toxin-encoding gene duplication described for some strains of Vibrio cholerae . The nucleotide sequences of the elt alleles are not identical (differing by 2 bp) and the duplicated region flanking the alleles extends 314 bp on one side and 1122 bp on the other side of each copy . Different partial copies of IS600 were identified 280 bp 3' to the stop codon of each allele . Partial and complete copies of other IS were also identified near the elt alleles . The data suggest that the regions surrounding the genes are hot spots for IS which would account for the observed heterogeneity in DNA flanking elt genes. J Gen Microbiol, 1991 Jul, 137 ( Pt 7), 1737 - 42 Purification and some properties of carboxynorspermidine synthase participating in a novel biosynthetic pathway for norspermidine in Vibrio alginolyticus; Nakao H et al.; Carboxynorspermidine synthase, mediates the nicotinamide-nucleotide-linked reduction of the Schiff base H2N(CH2)3N = CHCH2CH(NH2)COOH . This is formed from L-aspartic beta-semialdehyde (ASA) and 1,3-diaminopropane (DAP) and is reduced to carboxynorspermidine {H2N(CH2)3NH(CH2)2CH(NH2)COOH}, an intermediate in the novel pathway for norspermidine (NSPD) biosynthesis . The enzyme was purified to apparent homogeneity from Vibrio alginolyticus and characterized . The overall purification was about 1800-fold over the crude extract, with a yield of 33% . The enzyme displayed an apparent Mr of 93500 +/- 1000 by gel filtration and 45100 +/- 500 by SDS-PAGE, indicating that the native form is probably composed of two subunits of similar size . The specific activity of the purified enzyme was 31.0 mumol carboxynorspermidine produced min-1 (mg protein)-1 . The enzyme was activated by dithiothreitol, and inhibited by SH-reactive compounds . The pH and temperature optima were 7.25-7.5 and 37 degrees C, respectively . The Km value for the Schiff base was 4.68 mM, measured by varying the ASA concentration while keeping the DAP concentration constant . Putrescine was slightly active as a substrate, forming carboxyspermidine (at about 7% of the rate of DAP), but ethylenediamine, cadaverine and D-ASA were inert . The Km value for NADPH was 1.51 mM . NADH was a much poorer cofactor than NADPH . When V . alginolyticus was grown in the presence of 5 mM-NSPD, the specific activity of this enzyme was reduced by approximately 70% . NSPD also repressed two other enzymes responsible for its biosynthesis, 2,4-diaminobutyrate decarboxylase and carboxynorspermidine decarboxylase. Kansenshogaku Zasshi, 1991 Jul, 65(7), 833 - 7 {Molecular epidemiology of Vibrio cholerae O-1 from outbreak and sporadic patients in Nagoya in 1989}; Mori M et al.; Enterotoxigenic strains of Vibrio cholerae O-1 biotype eltor, isolated from three sporadic cases of cholera in Nagoya in 1989 and an outbreak of cholera in Nagoya in 1989 were analyzed for their similarities . All isolates of V . cholerae O-1 were indistinguishable in bacteriophage types, serovars, biovars and drug resistance patterns . Because the epidemiological investigation based on a primary structure of chromosomal DNA is more reliable, we isolated chromosomal DNA from these isolates and compared electrophoretic patterns of restriction endonuclease-digested DNA fragments . Furthermore, Southern hybridization of the cholera toxin gene was performed . Since no difference among six strains in these sporadic was observed, it was strongly suggested that both the independent cases and the outbreak of cholera were caused by the same strain. Kansenshogaku Zasshi, 1991 Jul, 65(7), 788 - 93 {Cholera toxin producibility by Vibrio cholerae isolated during the cholera outbreak in the NTT Nagoya Hall}; Matsumoto M et al.; An outbreak of cholera occurred among guests of the NTT Nagoya Hall in September 1989 . Clinical findings showed that all but one were symptomatic infections out of 44 bacteriologically confirmed cases . In relation to the high incidence of symptomatic infections, we examined cholera toxin (CT) producibility of the isolated V . cholerae . 1 . Strains of the NTT case produced 16-256 (mean 130) ng of CT per ml in CAYE-L medium at 30 degrees C and 32-256 (mean 142) ng of CT per ml by Polymyxin B treatment . But strains of past case produced 8-256 (mean 34), 8-128 (mean 44) ng of CT per ml, respectively . Strains of the NTT case produced a larger amount of CT than that of the past cases . 2 . Strains of the NTT case produced 512-4096 (mean 2100) ng of CT per ml in CAYE-L medium at 37 degrees C and 1024-2048 (mean 1600) ng of CT per ml by Polymyxin B treatment . But strains of the past case produced 8-64 (mean 25), 8-128 (mean 45) ng of CT per ml, respectively . Strains of the NTT case produced a larger an amount of CT than them of past case . We observed the same phenomenon in AKI medium at 37 degrees C . The yield of CT in CAYE-L medium was greater at 37 degrees C than 30 degrees C . 3 . Strains of NTT case grew faster than that of the past case in CAYE-L medium at 37 degrees C . But the growth rate was the same as both strains in AKI and CAYE media.(ABSTRACT TRUNCATED AT 250 WORDS) Kansenshogaku Zasshi, 1991 Jul, 65(7), 781 - 7 {Studies on the enteropathogenic mechanism of non-O1 Vibrio cholerae . III . Production of enteroreactive toxins}; Gyobu Y et al.; Cholera toxin gene and production of enteroreactive toxins were examined in 134 strains of non-O1 V . cholerae . Results obtained were summarized as follows . Frequencies of cholera-toxin-gene-positive strains were 2/58 (3.4%) from human sources and 2/76 (2.6%) from fish and environment . While, frequencies of production of hemolysin, fluid accumulating factor (FAF) related with protease, fluid accumulating factor in the suckling mouse, NAG-rTDH, NAG-ST and Vero toxin were 100, 72, 31, 2, 0 and 0%, respectively, for 58 strains from human sources, and 100, 57, 24, 0, 1.3 and 0%, respectively, for 76 strains from fish and environment . Among the 31 strains used for the injection of viable cells to the ligated rabbit ileal loop, detection frequencies of these enteroreactive toxins in the accumulated fluids were 100% for hemolysin, 3.2% for both FAF and NAG-rTDH and 0% for cholera toxin, Vero toxin or NAG-ST . Hemolysin and the fluid accumulating factor in the suckling mouse seemed to be identical in most strains . These results suggest that cholera toxin, NAG-ST, NAG-rTDH and Vero toxin may not be very important in the enteropathogenic mechanism of a great majority of non-O1 V . cholerae strains, whereas hemolysin may play an important role in the enteropathogenicity. J Clin Microbiol, 1991 Jul, 29(7), 1407 - 12 Production and characterization of monoclonal antibodies directed against the lipopolysaccharide of Francisella tularensis; Fulop MJ et al.; Two monoclonal antibodies (FT14 and FT2F11) directed against the lipopolysaccharide (LPS) of Francisella tularensis were produced for use in tests to detect the organism in environmental samples and clinical specimens . The specificity of the antibodies was determined by enzyme-linked immunosorbent assay (ELISA) and immunoblotting . Both antibodies detected LPS from F . tularensis by ELISA, but only one antibody, FT14, was serologically active in an immunoblot . Treatment of the LPS with detergents prior to ELISA eliminated its binding to FT2F11 but not FT14 . Qualitatively, both antibodies detected 10 different strains of F . tularensis by ELISA, but quantitatively, FT14 gave a detectable reaction with 10(3) organisms, whereas FT2F11 was able to detect only 10(5) organisms . FT14 did not cross-react with LPS from a range of other gram-negative species of bacteria, whereas FT2F11 cross-reacted against Vibrio cholerae LPS . Neither antibody showed cross-reactions when entire gram-negative organisms were used as antigens . In a competition ELISA, the two monoclonal antibodies were shown to compete for different epitopes . FT14 was strongly inhibited by purified O side chain from F . tularensis LPS, but FT2F11 was only weakly inhibited . It was inferred from those results that FT14 is directed against the O side chain and that FT2F11 is directed against the core. Rev Argent Microbiol, 1991 Jul-Sep, 23(3), 160 - 5 {Bacterial flora of the digestive tract of specimens of Notothenia neglecta caught in Caleta Potter (South Shetland Archipelago, Antarctica)}; MacCormack WP et al.; A qualitative and quantitative study of the predominant heterotrophic bacterial flora in the stomach and intestine of the Antarctic fish Notothenia neglecta was carried out: 10 newly caught specimens (Potter cove, King George Island, South Shetland Islands) were analyzed . The cultures were made under aerobic and anaerobic conditions . The stomach flora showed variable results between samples which are probably related to the flora ingested with food . The gut flora was composed almost exclusively of Vibrio spp . These results are in agreement with those attributing to Vibrio the nature of indigenous flora of the intestine of marine teleosts and show that this flora had not changed, not even during the adaptation of these fish to the extreme Antarctic environmental conditions. Trans R Soc Trop Med Hyg, 1991 Jul-Aug, 85(4), 544 - 7 Identification of Vibrio cholerae by enzyme electrophoresis; Salles CA et al.; Zymovar analysis of 260 strains of Vibrio cholerae plus 3 reference strains of V . mimicus, using 13 structural loci, led to the grouping of strains in 73 zymovars (strain or group of strains sharing the same alleles) . Effective separation of strains, distinction of V . cholerae strains from closely related V . mimicus and the detection of 2 vibrio strains, including one with two O1 serovars, in supposedly pure collection cultures, illustrate the potential of zymovar analysis in the identification of V . cholerae isolates . Two El Tor strains from USA, one CT+ and the other CT-, shared the same zymovar 71, while 127 typical El Tor strains belonged to zymovar 14. Zh Mikrobiol Epidemiol Immunobiol, 1991 Jul, (7), 55 - 8 {The characteristics of the reactogenicity and immunological activity of a new cholera bivalent chemical vaccine based on the results of controlled trials}; Sumarokov AA et al.; The reactogenic properties and immunological potency of modified cholera chemical vaccine (choleragen-toxoid + O-antigens Inaba and Ogawa) were tested in 278 volunteers aged 18 years and over in comparison with those of a commercial batch of monovalent cholera vaccine (choleragen-toxoid + O-antigen Inaba) . The cholera vaccine, enriched with O-antigen Ogawa, was found to be safe; vaccination with this vaccine was not accompanied by the development of systemic and local reactions whose frequency and intensity met the requirements for the reactogenic properties of commercial cholera vaccine . The immunological potency of the bivalent vaccine with respect to strain Inaba was not inferior to that of the commercial vaccine; at the same time in persons immunized with the new preparation the titers of vibriocidal antibodies to strain of serovar Inaba were five-fold higher . The conclusion on the expediency of using cholera chemical vaccine enriched with O-antigen Ogawa was made. Infect Immun, 1991 Jul, 59(7), 2508 - 12 Immunogenicity of Vibrio cholerae O1 toxin-coregulated pili in experimental and clinical cholera; Hall RH et al.; A functional tcpA gene, encoding the major subunit of toxin-coregulated pili (TCP), is necessary for Vibrio cholerae O1 Ogawa strain 395 to colonize the human intestine and confer protective immunity to virulent challenge . The immunogenicity of TCP and other antigens in experimental and naturally acquired cholera was determined . Seroconversion to cholera toxin (CT), whole cell preparations, and to Ogawa lipopolysaccharide but not to purified native TCP or to a TcpA mimiotope was found in volunteers . Local intestinal secretory immunoglobulin A from volunteers showed conversions to cholera toxin and lipopolysaccharide but not to TCP . Cholera patients in Indonesia showed a seroconversion rate to TCP of 3 of 6 and a seroconversion to a TcpA mimiotope of 1 of 6 . Volunteer and patient sera showed similar vibriocidal seroconversions when assayed against either TCP-positive and TCP-negative V . cholerae O1 strains, suggesting that TCP do not contribute demonstrably to the vibriocidal antigen . We conclude that although seroconversion to TCP can occur in naturally acquired cholera, solid long-term protection can be engendered in the absence of a detectable anti-TCP immune response. FEBS Lett, 1991 Jun 24, 284(2), 273 - 6 F0F1-ATPase from Vibrio alginolyticus . Subunit composition and proton pumping activity; Dmitriev OYu et al.; An F0F1-ATPase was isolated from the membranes of the marine bacterium Vibrio alginolyticus . Homology between the subunits of the F0-complexes from E . coli and V . alginolyticus was found using antibodies against subunits a, b and c of the E . coli F0F1-ATPase . The F0F1-complex from V . alginolyticus was reconstituted into proteoliposomes, which were competent in ATP-dependent proton uptake . This process was inhibited by triphenyltin, DCCD, and venturicidin . Na+ did not affect proton translocation. Biochim Biophys Acta, 1991 Jun 19, 1084(1), 13 - 20 The cis/trans isomerization of the double bond of a fatty acid as a strategy for adaptation to changes in ambient temperature in the psychrophilic bacterium, Vibrio sp . strain ABE-1; Okuyama H et al.; The major phospholipid, phosphatidylethanolamine (PE), of Vibrio sp . strain ABE-1 contains a unique trans-unsaturated fatty acid, 9-trans-hexadecenoic acid (16:1(9t}, at the sn-2 position of the glycerol moiety . The major molecular species of PE that contain 16:1(9t) at the sn-2 position have either 9-cis-hexadecenoic acid (16:1(9c} or hexadecanoic acid (16:0) at the sn-1 position . The transition temperatures of the liquid-crystal to the gel phase of 16:1(9c)/16:1(9t)-PE and 16:0/16:1(9t)-PE were -3 degrees C and 38 degrees C, respectively, temperatures that were 31 degrees C and 18 degrees C higher than the corresponding temperatures for 16:1(9c)/16:1(9c)-PE and 16:0/16:1(9c)-PE . The proportion of 16:1(9c)/16:1(9t)-PE and 16:0/16:1(9t)-PE increased significantly in cells grown at 20 degrees C over that in cells grown at 5 degrees C . When cells grown at 5 degrees C were incubated at 20 degrees C in the presence of cerulenin, an inhibitor of the synthesis de novo of fatty acids, the level of 16:1(9t) increased almost in parallel with a concomitant decrease in the level of 16:1(9c) at the sn-2 position . These results suggest that 16:1(9c) is converted to 16:1(9t) by the cis/trans isomerization of the double bond in the fatty acid . This conversion is discussed as a possible strategy for adaptation by bacteria to changes in temperature. Biochemistry, 1991 Jun 18, 30(24), 6070 - 4 Action of a microbial lipase/acyltransferase on phospholipid monolayers; Hilton S et al.; Vibrio species release a lipase which shares many properties with mammalian lecithin-cholesterol acyltransferase . We have studied the action of the enzyme on phospholipid monolayers . At similar surface pressures, reaction velocities were higher with monolayers of dilauroylphosphatidylcholine than with the corresponding phosphatidylglycerol or phosphatidylethanolamine . The dependence of reaction velocity on molecular density was very similar for phosphatidylcholine and phosphatidylethanolamine monolayers . Lag times were shortest with phosphatidylglycerol at low molecular densities, but maximum velocity was reached at considerably lower densities than with the other two lipids . We have found {Hilton, S., McCubbin, N . D., Kay, C., & Buckley, J.T . (1990) Biochemistry 29, 9072-9078} that nicking of the enzyme with trypsin or other proteases results in an increase in its activity against lipids in membranes . Here we show that trypsin treatment results in a large change in the surface activity of the lipase, allowing it to penetrate monolayers at pressures higher than 40 mN.m-1. Proc Natl Acad Sci U S A, 1991 Jun 15, 88(12), 5403 - 7 Regulatory cascade controls virulence in Vibrio cholerae; DiRita VJ et al.; Expression of more than 17 virulence genes in Vibrio cholerae is under the coordinate control of the ToxR protein . ToxR is a transmembrane protein that binds to and activates the promoter of the operon encoding cholera toxin . As yet, the ability of ToxR to activate directly other genes in this regulon has not been demonstrated . We have cloned a gene called toxT from V . cholerae 569B; the toxT gene product, like ToxR, can activate the ctx promoter in Escherichia coli . In addition, expression of other genes identified as members of the ToxR regulon (tcpA, tcpI, aldA, and tagA) can be activated in E . coli by the toxT gene product but not by ToxR . When expressed from a constitutive promoter, the toxT gene product partially suppresses the ToxR- phenotype of a toxR deletion mutant of V . cholerae . The level of toxT mRNA is greatly reduced in a toxR mutant of V . cholerae . In addition, growth conditions under which the ToxR regulon is not expressed also repress the synthesis of toxT mRNA . These results suggest that ToxR controls transcription of toxT, whose product in turn is directly responsible for activation of several virulence genes under ToxR control. Proc Natl Acad Sci U S A, 1991 Jun 15, 88(12), 5242 - 6 Vibrio cholerae produces a second enterotoxin, which affects intestinal tight junctions; Fasano A et al.; Attenuated Vibrio cholerae vaccine strains specifically mutated in genes encoding cholera toxin (CT) are still capable of causing mild to moderate diarrhea . Culture supernatants of V . cholerae strains, both CT-positive and CT-negative, were examined in Ussing chambers, and a toxin was found that increases the permeability of the small intestinal mucosa by affecting the structure of the intercellular tight junction, or zonula occludens . The activity of this toxin is reversible, heat-labile, sensitive to protease digestion, and found in culture supernatant fractions containing molecules between 10 and 30 kDa in size . Production of this factor (named ZOT for zonula occludens toxin) correlates with diarrheagenicity of V . cholerae strains in volunteers and may represent another virulence factor of infectious diarrhea that must be eliminated to achieve a safe and effective live oral vaccine against cholera. J Bacteriol, 1991 Jun, 173(11), 3311 - 7 Cloning and nucleotide sequence of the Vibrio cholerae hemagglutinin/protease (HA/protease) gene and construction of an HA/protease-negative strain; Hase CC et al.; The structural gene hap for the extracellular hemagglutinin/protease (HA/protease) of Vibrio cholerae was cloned and sequenced . The cloned DNA fragment contained a 1,827-bp open reading frame potentially encoding a 609-amino-acid polypeptide . The deduced protein contains a putative signal sequence followed by a large propeptide . The extracellular HA/protease consists of 414 amino acids with a computed molecular weight of 46,700 . In the absence of protease inhibitors, this is processed to the 32-kDa form which is usually isolated . The deduced amino acid sequence of the mature HA/protease showed 61.5% identity with the Pseudomonas aeruginosa elastase . The cloned hap gene was inactivated and introduced into the chromosome of V . cholerae by recombination to construct the HA/protease-negative strain HAP-1 . The cloned fragment containing the hap gene was then shown to complement the mutant strain. J Infect Dis, 1991 Jun, 163(6), 1235 - 42 Field trial of oral cholera vaccines in Bangladesh: serum vibriocidal and antitoxic antibodies as markers of the risk of cholera; Clemens JD et al.; The relationship of serum vibriocidal (VC) and IgG anti-cholera toxin (CT) antibodies to the risk of cholera was evaluated during the first year of follow-up of recipients of three oral doses of B subunit (BS)-whole-cell vaccine, whole-cell vaccine, or Escherichia coli K12 strain placebo in Bangladesh . Acute sera from 121 cholera patients were compared with sera from 2592 contemporaneous community controls . Each doubling of VC titer was associated, on average, with a 22%-47% reduction of cholera risk in the three groups . In contrast, in the two groups that did not receive BS, anti-CT titers were directly associated with cholera and thus served as markers of higher cholera risk . Each vaccine conferred approximately 65% protective efficacy against cholera, but antibody titers did not correlate with vaccine efficacy, indicating that serum VC and anti-CT antibodies are poor markers of the longitudinal pattern of vaccine efficacy. Infect Immun, 1991 Jun, 59(6), 2186 - 8 Purification and characterization of a new heat-stable enterotoxin produced by Vibrio cholerae non-O1 serogroup Hakata; Arita M et al.; The possible production of a heat-stable enterotoxin (Vc-H-ST) by Vibrio cholerae non-O1 serogroup Hakata was investigated, and the purified Vc-H-ST was characterized . It has a unique amino acid sequence, LIDCCEICCNPACFGCLN . This sequence is quite similar to that of the heat-stable enterotoxin (NAG-ST) produced by V . cholerae non-O1 except for one amino acid (leucine) residue excess at the N terminus . Other characteristics, including biological activity, are compatible with those of NAG-ST. Cell Immunol, 1991 Jun, 135(1), 184 - 94 Preferential reactivity of autoantibodies in murine lupus NZB mice to neuraminidase-treated monosialogangliosides on B cells of mouse spleen; Noguchi M et al.; When analyzed by flow cytometry, reactivity of IgM autoantibodies in sera from NZB mice to spleen B cells, but not to T cells, from BALB/c mice was remarkably increased after treatment of the cells with Vibrio cholerae neuraminidase . By TLC immunostaining with the antibodies, neither neutral nor acidic glycosphingolipids from both BALB/c and NZB mouse spleens were found to be reactive, but after neuraminidase treatment of the TLC plate, prior to the immunostaining, three components became reactive . All of the reactive glycosphingolipids were found to carry a single sialic acid residue and were at a concentration less than 1.3% of the total lipid-bound sialic acids . Their mobilities on TLC plate were close to those of IV3 NeuAcnLc4Cer, IV3 NeuAcII3 NeuAcGg4Cer, and IV3 NeuAcII3 NeuAc2Gg4Cer . In addition, the monosialogangliosides, which became reactive with the autoantibodies after neuraminidase treatment, were found to be predominantly distributed on B cells from BALB/c mice spleen, but not on T cells by TLC immunostaining . These studies demonstrate that the majority of IgM autoantibodies to spleen lymphocytes in sera from NZB mice might react preferentially to terminal sugar residues of three new glycosphingolipids masked by a single sialic acid on B cells, but not on T cells. Zentralbl Bakteriol, 1991 Jun, 275(2), 256 - 63 Toxin production by atypical strains of Vibrio cholerae E1 Tor under different cultural conditions; Chakrabarti MK et al.; It was observed that at 37 degrees C under in vitro conditions, aerobic culture filtrates of a few strains of Vibrio cholerae biotype El Tor isolated from diarrhoeal cases produced a minute amount of toxin which failed to elicit a positive ileal loop reaction like toxigenic strains . Thus, these strains showed an atypical behaviour in their toxin producing ability . At 25 degrees C and 30 degrees C under aerobic cultural conditions enhanced toxin production was noticed in toxigenic strains, but these temperatures did not affect the toxigenicity of the atypical strains . The atypical Vibrio cholerae El Tor strains exhibited enhanced toxin production only at 37 degrees C under anaerobic conditions and the amount of toxin produced was akin to those of the toxigenic strains . In comparison to aerobic conditions, growth was observed to be comparatively lower under anaerobiosis both in the toxigenic and atpyical V . cholerae strains . Moreover, in contrast to the toxigenic strains, the toxin did not remain membrane-bound in these atypical strains at 37 degrees C and aerobic cultural conditions. Kansenshogaku Zasshi, 1991 Jun, 65(6), 665 - 71 {Studies on the enteropathogenic mechanism of non-O1 Vibrio cholerae . II . Lethality, adhesion, colonization and cytopathogenicity of enteropathogenic strains}; Gyobu Y et al.; Lethality, adhesion, colonization, hemagglutinable activity, invasiveness and cytopathogenicity of non-O1 V . cholerae were compared between enteropathogenic and non-enteropathogenic strains . The following results were obtained . 1) Minimum lethal doses (MLD) of enteropathogenic strains were significantly lower than those of non-enteropathogenic strains . 2) There were no differences in adhesive and hemagglutinating activities between enteropathogenic and non-enteropathogenic strains . 3) A greater majority of enteropathogenic strains showed cytopathogenic effect on HEp 2 cells, but non-enteropathogenic strains did not . 4) Regardless of enteropathogenicity of viable cells, none of the 13 strains examined were found to be invasive to HEp 2 cells . These results suggest that adhesion and colonization do not draw a clear distinction between enteropathogenic and non-enteropathogenic strains, and that both lethal and cytopathogenic activities of these organisms are correlated with enteropathogenicity. Zh Mikrobiol Epidemiol Immunobiol, 1991 Jun, (6), 37 - 40 {The 7th cholera pandemic in the world and the USSR}; Narkevich MI et al.; 1,713,057 cases of cholera were registered in the world during the seventh pandemic of the disease at the period of 1961-1989 . The pandemic still continues, being the most prolonged pandemic in comparison with earlier ones . During the period of the seventh pandemic 10,723 cases of cholera were registered in the USSR . Great outbreaks occurred in 1965 and 1970-1974 . At present sporadic cases of cholera can be registered, and wide circulation of mainly avirulent, nontoxigenic strains of cholera vibrios in environmental objects is characteristic of the epidemic situation. Zh Mikrobiol Epidemiol Immunobiol, 1991 Jun, (6), 25 - 9 {The genomic fingerprinting of the causative agents of sapronoses}; Shaginian IA et al.; The genome polymorphism of the causative agents of sapronoses (Vibrio cholerae, Legionella and Leptospira) has been studied . The use of the method of genome fingerprinting {correction of dactyloscopy} has been shown to permit the differentiation of closely related strains of such causative agents . The epidemically significant strains of the causative agents of sapronoses, isolated in different geographical regions, have been found to be genotypically related, i.e., they are probably of clonal origin . Avirulent and nontoxigenic strains are genotypically heterogeneous and differ both from one another and from epidemically significant strains . Using V . cholerae as an example, the hypothesis of the appearance of potentially dangerous variants at the epidemic period in the absence of their release at the period between epidemics is considered. Cent Afr J Med, 1991 Jun, 37(6), 186 - 9 Serotype variation in vibrio cholerae el tor diarrhoea in northern Nigeria; Onyemelukwe GC et al.; Serotyping of Vibrio cholerae organisms causing epidemics in Zaria and environs since 1975 to 1986 shows that Hikojima serotype was prevalent from 1976-1978, but Ogawa became prevalent from 1984 till 1986 . The internal and external pressures responsible for these selections are unclear. Gene, 1991 May 15, 101(1), 45 - 50 Nucleotide sequence and analysis of the Vibrio alginolyticus scr repressor-encoding gene (scrR); Blatch GL et al.; The nucleotide sequence of the Vibrio alginolyticus scr repressor-encoding gene (scrR) was determined . The deduced amino acid sequence of the scr repressor was homologous with the gal, lac and cyt repressors of Escherichia coli and contained a helix-turn-helix DNA binding domain . Although the scrR gene encoded a protein which was required for the regulation of the V . alginolyticus sucrose utilization system, a particular deletion in the scrR gene could not be complemented in trans . The lack of complementation was discussed in terms of the possible involvement of a cis regulatory element or interference by the truncated scr repressor. Experientia, 1991 May 15, 47(5), 429 - 31 The phenomenon of toxin secretion by vibrios and aeromonads; Hirst TR et al.; Vibrio and Aeromonas species have a remarkable ability to secrete extracellular proteins, including toxins, haemagglutinins and other virulence factors . Here we discuss the pathways and potential mechanisms of toxin secretion through the double-membraned envelopes which surround these organisms. FEMS Microbiol Lett, 1991 May 15, 64(2-3), 259 - 63 Analysis of the gene of Vibrio hollisae encoding the hemolysin similar to the thermostable direct hemolysin of Vibrio parahaemolyticus; Yamasaki S et al.; The gene (designated as Vh-tdh) of Vibrio hollisae 9041 encoding a hemolysin similar to the thermostable direct hemolysin (TDH) of V . parahaemolyticus contained a 567-base-pair open reading frame (ORF), which was 93.3-93.5% homologous to those of the tdh genes of V . parahaemolyticus, V . cholerae non-01, and V . mimicus encoding TDH or similar hemolysins . Comparative analysis of the nucleotide sequence containing the Vh-tdh ORF with published nucleotide and amino acid sequences suggested that the Vh-tdh gene and other tdh genes diverged from a common ancestral gene, that the divergence was closely associated with the evolutionary divergence of V . hollisae from other species of genus Vibrio, and that strain-to-strain variation of the Vh-tdh gene exists in V . hollisae. J Immunol, 1991 May 15, 146(10), 3550 - 6 GTP-binding proteins transduce signals generated via human FC gamma receptor IIIA (CD16); Procopio AD et al.; This study demonstrates that GTP-binding proteins regulate Fc gamma RIII-mediated signal transduction and inositol phosphate (IPn) generation in human NK cells . In a