Toxicol Lett, 1996 Aug, 86(2-3), 155 - 62 Environmental chemicals relevant for respiratory hypersensitivity: the indoor environment; Becher R et al.; The allergenic constituents of non-industrial indoor environments are predominantly found in the biologic fraction . Several reports have related biological particles such as mites and their excreta, dander from pets and other furred animals, fungi and bacteria to allergic manifestations including respiratory hypersensitivity among the occupants of buildings . Also, bacterial cell-wall components and the spores of toxin-producing moulds may contribute to the induction of hypersensitivity, but the relevance for human health is not yet determined . The knowledge regarding hypersensitivity and asthmatic reactions after exposure to chemical agents is primarily based on data from occupational settings with much higher exposure levels than usually found in non-industrial indoor environments . However, there is evidence that indoor exposure to tobacco smoke, some volatile organic compounds (VOC) and various combustion products (either by using unvented stoves or from outdoor sources) can be related to asthmatic symptoms . In some susceptible individuals, the development of respiratory hypersensitivity or elicitation of asthmatic symptoms may also be related to the indiscriminate use of different household products followed by exposure to compounds such as diisocyanates, organic acid anhydrides, formaldehyde, styrene and hydroquinone . At present, the contribution of the indoor environment both to the development of respiratory hypersensitivity and for triggering asthmatic symptoms is far from elucidated. Clin Exp Immunol, 1996 Aug, 105(2), 213 - 9 Chronic mucocutaneous candidiasis . II . Class and subclass of specific antibody responses in vivo and in vitro; Lilic D et al.; Patients with chronic mucocutaneous candidiasis (CMC) succumb to persistent infections with the opportunistic yeast Candida . Impaired cell-mediated responses to Candida have been repeatedly reported while antibody responses were mostly found to be normal . The underlying defect remains poorly understood . It has recently been shown that CMC patients are also susceptible to infections with encapsulated bacteria, and may have associated IgG2 and IgG4 deficiency . Our previous studies demonstrated altered cytokine production in CMC patients . As cytokines can influence production and isotype of specific antibody, in 10 patients with CMC we measured the levels and isotype distribution of serum antibodies to Candida antigens (CAg), pneumococcal polysaccharide (PPS) and tetanus toxoid (TT) antigens . Peripheral blood lymphocytes were also stimulated in culture and the antibodies made in vitro were measured . Our data demonstrated that in vivo, CMC patients had very high levels of IgG and IgA CAg-specific antibodies . CAg-specific and PPS-specific IgG1 was markedly higher than in controls . Children but not adults with CMC had significantly lower levels of IgG2-specific antibody to CAg and PPS compared with age-matched controls . Patients had significantly higher levels of IgG3-specific antibody to all three antigens tested . These findings were in accordance with increased total IgG and IgG3 levels seen in CMC patients . In vitro, CMC patients, particularly children, did not respond as frequently to antigen stimulation as did their healthy controls . The level of specific antibody produced was also lower to all antigens tested, as was the amount of total immunoglobulins following antigenic and particularly mitogenic stimulation . Addition of interferon-alpha (IFN-alpha) or IFN-gamma to cultures had variable, sometimes marked, effects . Our results demonstrate that CMC patients manifest subtle alterations in specific antibody responses to CAg, PPS and TT, which are most pronounced in children . This may relate to altered cytokine production also seen in these patients. Am J Respir Cell Mol Biol, 1996 Aug, 15(2), 207 - 15 Characterization of a neutrophil inhibitor peptide harvested from human bronchial lavage: homology to influenza A nucleoprotein; Cooper JA Jr et al.; Bronchi are exposed to particulate matter, including bacteria, fungi and dusts, that should trigger release of molecules which attract polymorphonuclear neutrophils (PMN) . However, normal bronchi are relatively devoid of PMN, suggesting that there exists a mechanism to dampen acute inflammation in the lung . We have previously reported that bronchial lavage from normal humans contains a nonpolar peptide that inhibits PMN chemotaxis and oxidant production . In the present study we devised preparative methods to obtain sufficient quantities of a similar inhibitor molecule for partial amino acid sequencing and allow production of truncated analogues . Amino acid sequencing demonstrated that the peptide includes a 10-amino-acid sequence that is completely homologous to a sequence of amino acids contained in the influenza A nucleoprotein . Synthesized peptides containing this 10-amino-acid sequence inhibited PMN chemotaxis and oxidant production . In addition, PMN lysates actively phosphorylated peptides containing the 10-amino-acid sequence or a partial sequence containing an apparent phosphorylation site . U937 cells were noted to be one source of this inhibitor, as a similarly sized nonpolar inhibitor peptide was purified from U937 culture supernatants . In addition, U937 and monocyte cellular lysates contained proteins recognized by an antiserum directed at the influenza A nucleoprotein . Further characterization of the molecule described in this study or related molecules may lead to significantly new antiinflammatory strategies. Appl Environ Microbiol, 1996 Aug, 62(8), 3034 - 6 Analysis of partial sequences of genes coding for 16S rRNA of actinomycetes isolated from Casuarina equisetifolia nodules in Mexico; Niner BM et al.; Filamentous bacteria isolated from surface-sterilized nodules of Casuarina equisetifolia trees in Mexico were capable of reducing acetylene, a diagnostic test for nitrogenase, but were unable to nodulate their host . Analysis of partial 16S rRNA gene sequences suggests that the Mexican isolates are not Frankia strains but members of a novel clade. Appl Environ Microbiol, 1996 Aug, 62(8), 2904 - 9 Amplification of 16S rRNA genes from Frankia strains in root nodules of Ceanothus griseus, Coriaria arborea, Coriaria plumosa, Discaria toumatou, and Purshia tridentata; Benson DR et al.; To study the global diversity of plant-symbiotic nitrogen-fixing Frankia strains, a rapid method was used to isolate DNA from these actinomycetes in root nodules . The procedure used involved dissecting the symbiont from nodule lobes; ascorbic acid was used to maintain plant phenolic compounds in the reduced state . Genes for the small-subunit rRNA (16S ribosomal DNA) were amplified by the PCR, and the amplicons were cycle sequenced . Less than 1 mg (fresh weight) of nodule tissue and fewer than 10 vesicle clusters could serve as the starting material for template preparation . Partial sequences were obtained from symbionts residing in nodules from Ceanothus griseus, Coriaria arborea, Coriaria plumosa, Discaria toumatou, and Purshia tridentata . The sequences obtained from Ceonothus griseus and P . tridentata nodules were identical to the sequence previously reported for the endophyte of Dryas drummondii . The sequences from Frankia strains in Coriaria arborea and Coriaria plumosa nodules were identical to one another and indicate a separate lineage for these strains . The Frankia strains in Discaria toumatou nodules yielded a unique sequence that places them in a lineage close to bacteria that infect members of the Elaeagnaceae. Appl Environ Microbiol, 1996 Aug, 62(8), 2710 - 5 Characterization of active recombinant 2,3-dihydro-2,3-dihydroxybiphenyl dehydrogenase from Comamonas testosteroni B-356 and sequence of the encoding gene (bphB); Sylvestre M et al.; 2,3-Dihydro-2,3-dihydroxybiphenyl-2,3-dehydrogenase (B2,3D) catalyzes the second step in the biphenyl degradation pathway . The nucleotide sequence of Comamonas testosteroni B-356 bphB, which encodes B2,3D, was determined . Structural analysis showed that the dehydrogenases involved in the bacterial degradation of aromatic compounds are related to each other and that their phylogenetic relationships are very similar to the relationships observed for dioxygenases that catalyze the initial reaction in the degradation pathway . The bphB sequence was used to produce recombinant active His-tagged B2,3D, which allowed us to describe for the first time some of the main features of a B2,3D . This enzyme requires NAD+, its optimal pH is 9.5, and its native M(r) was found to be 123,000, which makes it a tetramer . These characteristics are very similar to those reported for the related enzyme cis-toluene dihydrodiol dehydrogenase . The Km value and maximum rate of metabolism for 2,3-dihydro-2,3-dihydroxybiphenyl were 73 +/- 16 microM and 46 +/- 4 nmol min-1 microgram-1, respectively . Compared with the cis-toluene dihydrodiol dehydrogenase, B2,3D appeared to be more substrate specific since it was unable to attack cis-1,2-dihydroxy-cyclohexa-3,5-diene. Gastroenterology, 1996 Aug, 111(2), 419 - 25 Helicobacter pylori urease is a potent stimulus of mononuclear phagocyte activation and inflammatory cytokine production; Harris PR et al.; BACKGROUND & AIMS: Helicobacter pylori surface proteins induce the production of proinflammatory mediators by mononuclear phagocytes, but the protein responsible for this stimulation has not been identified . This study determined whether urease, the major component of the soluble proteins extracted from H . pylori grown in culture, activates mononuclear phagocytes and stimulates them to produce proinflammatory cytokines . METHODS: Primary human blood monocytes were incubated with column-purified H . pylori urease and assayed by flow cytometry, Immunoassay, and reverse-transcription polymerase chain reaction for phenotypic, functional, and molecular evidence of activation . RESULTS: H . pylori urease induced monocyte expression of surface interleukin 2 receptors and increased expression of HLA-DR, phenotypic changes consistent with activation . Urease also stimulated dose-dependent production of interleukin 1 beta, interleukin 6, interleukin 8, and tumor necrosis factor alpha peptides and messenger RNA . These urease-induced phenotypic and functional changes were inhibited by preincubation of the urease with antisera to H . pylori whole bacteria, purified urease, or the 31-kilodalton subunit of urease . CONCLUSIONS: Among the soluble proteins released by H . pylori, urease is capable of activating monocytes for proinflammatory cytokines production . The local production of cytokines by urease-stimulated mononuclear phagocytes may play a central role in the development of H . pylori gastroduodenal inflammation. Nature, 1996 Aug 1, 382(6590), 471 - 3 Visualization of ordered genomic RNA and localization of transcriptional complexes in rotavirus; Prasad BV et al.; In double-stranded-RNA (dsRNA) viruses found in animals, bacteria and yeast, the genome is transcribed within the structurally intact core of the virion with extraordinary efficiency . The structural organization of the genome and the enzymes involved in the transcription inside any of these viruses, critical for understanding this process, is not known . Here we report what we believe is the first three-dimensional characterization of the viral genome and the transcription complex in a prototypical dsRNA virus . Rotavirus is a large (diameter 1,000 A) icosahedral virus composed of three capsid protein layers and 11 dsRNA segments . It is the most important cause of gastroenteritis in children, accounting for over a million deaths annually . We show that viral dsRNA forms a dodecahedral structure in which the RNA double helices, interacting closely with the inner capsid layer, are packed around the enzyme complex located at the icosahedral 5-fold axes . The ordered RNA accounts for about 4,500 out of a total 18,525 base pairs in the genome, the largest amount of icosahedrally ordered RNA observed in any virus structure to date . We propose that the observed organization of the dsRNA is conducive for an orchestrated movement of the RNA relative to the enzyme complex during transcription. Biochim Biophys Acta, 1996 Jul 31, 1275(3), 161 - 203 The ferritins: molecular properties, iron storage function and cellular regulation; Harrison PM et al.; The iron storage protein, ferritin, plays a key role in iron metabolism . Its ability to sequester the element gives ferritin the dual functions of iron detoxification and iron reserve . The importance of these functions is emphasised by ferritin's ubiquitous distribution among living species . Ferritin's three-dimensional structure is highly conserved . All ferritins have 24 protein subunits arranged in 432 symmetry to give a hollow shell with an 80 A diameter cavity capable of storing up to 4500 Fe(III) atoms as an inorganic complex . Subunits are folded as 4-helix bundles each having a fifth short helix at roughly 60 degrees to the bundle axis . Structural features of ferritins from humans, horse, bullfrog and bacteria are described: all have essentially the same architecture in spite of large variations in primary structure (amino acid sequence identities can be as low as 14%) and the presence in some bacterial ferritins of haem groups . Ferritin molecules isolated from vertebrates are composed of two types of subunit (H and L), whereas those from plants and bacteria contain only H-type chains, where 'H-type' is associated with the presence of centres catalysing the oxidation of two Fe(II) atoms . The similarity between the dinuclear iron centres of ferritin H-chains and those of ribonucleotide reductase and other proteins suggests a possible wider evolutionary linkage . A great deal of research effort is now concentrated on two aspects of ferritin: its functional mechanisms and its regulation . These form the major part of the review . Steps in iron storage within ferritin molecules consist of Fe(II) oxidation, Fe(III) migration and the nucleation and growth of the iron core mineral . H-chains are important for Fe(II) oxidation and L-chains assist in core formation . Iron mobilisation, relevant to ferritin's role as iron reserve, is also discussed . Translational regulation of mammalian ferritin synthesis in response to iron and the apparent links between iron and citrate metabolism through a single molecule with dual function are described . The molecule, when binding a {4Fe-4S} cluster, is a functioning (cytoplasmic) aconitase . When cellular iron is low, loss of the {4Fe-4S} cluster allows the molecule to bind to the 5'-untranslated region (5'-UTR) of the ferritin m-RNA and thus to repress translation . In this form it is known as the iron regulatory protein (IRP) and the stem-loop RNA structure to which it binds is the iron regulatory element (IRE) . IREs are found in the 3'-UTR of the transferrin receptor and in the 5'-UTR of erythroid aminolaevulinic acid synthase, enabling tight co-ordination between cellular iron uptake and the synthesis of ferritin and haem . Degradation of ferritin could potentially lead to an increase in toxicity due to uncontrolled release of iron . Degradation within membrane-encapsulated "secondary lysosomes' may avoid this problem and this seems to be the origin of another form of storage iron known as haemosiderin . However, in certain pathological states, massive deposits of "haemosiderin' are found which do not arise directly from ferritin breakdown . Understanding the numerous inter-relationships between the various intracellular iron complexes presents a major challenge. Biochim Biophys Acta, 1996 Jul 31, 1275(3), 145 - 50 Molecular cloning, DNA sequence and transcriptional analysis of the Rhodospirillum molischianum B800/850 light-harvesting genes; Germeroth L et al.; The amino acid sequences of the B800/850 light-harvesting proteins from Rhodospirillum molischianum were determined by Edman degradation . On the basis of these amino acid sequences, two degenerated oligonucleotides were synthesized and used for PCR of genomic DNA . The resulting 150 bp DNA fragment was cloned, sequenced and used for subsequent Southern blot analysis of digested genomic DNA . A 2.3 kbp EcoRI fragment strongly hybridized to the probe and a size selected genomic library from genomic DNA was constructed . One clone scored positive during screening of the library with the PCR-fragment and subsequent DNA sequence analysis of the clone revealed the presence of three A-genes (A1A2A3) encoding alpha-polypeptides and of two B-genes (B1B2) encoding beta-polypeptides of the B800/850 complex . The arrangement of the different genes are B1A1, B2A2 and A3 where only B1 and B2 are preceded by typical Shine-Dalgarno sequences . In addition, typical nucleotide sequences for a rho-independent termination of transcription are located downstream of the genes A1 and A2 . The deduced amino acid sequences revealed that the alpha-genes encoded for identical polypeptides, whereas the deduced beta-polypeptides differed in their amino acid sequence at four positions . Transcriptional operon analysis revealed that the genes A1B1 and A2B2 are both dicistronically transcribed, whereas the gene A3 is not. Biochemistry, 1996 Jul 30, 35(30), 9925 - 34 Energy and electron transfer upon selective femtosecond excitation of pigments in membranes of Heliobacillus mobilis; Liebl U et al.; Excitation energy transfer steps in membranes of Heliobacillus mobilis were directly monitored by transient absorption spectroscopy with a time resolution of 30 fs under selective excitation within the inhomogeneously broadened bacteriochlorophyll g QY band . The initial anisotropy was found to be > 0.4, indicating that the pigments are excitonically coupled . After initial decay of this anisotropy in < 50 fs, major sub-picosecond components associated with spectral equilibration were identified, corresponding to uphill energy transfer with a 300 fs time constant (812 nm excitation) and downhill energy transfer with 100 and 500 fs components (770 nm excitation) . These equilibrations are ascribed predominantly to single excitation transfer steps, as anisotropy measurements showed that equilibration within spectrally similar pigments occurs on the same time scale as spectral equilibration, a situation which contrasts with that in photosystem I . Downhill energy transfer occurs to a significant extent directly to an energetically heterogeneous population of excited states as well as in a sequential way via gradually lower-lying pools of bacteriochlorophyll g . This finding supports a description in which all pigments, including the bluemost absorbing, are spatially organized in a random way rather than in clusters of spectrally similar species . Spectral equilibration is not entirely completed prior to formation of the primary radical pair P798 + A0-, which was found to proceed in a multiexponential way (time constants of 5 and 30 ps) . No indication for the formation of radical species other than P798 + A0- on the time scale up to 100 ps was found. Neuroreport, 1996 Jul 29, 7(11), 1730 - 2 Metabolism of agmatine into urea but not into nitric oxide in rat brain; Gilad GM et al.; Agmatine is a guanidino compound abundant in bacteria and plants where it serves as a precursor for polyamine synthesis . It can interfere with several neurotransmission-related functions and can exert neuroprotective effects after brain injury . Agmatine was recently identified in mammalian brain and its synthesis by arginine decarboxylation was characterized . Its metabolism by the brain is, however, unknown . Here we report evidence indicating that agmatine can be selectively metabolized in the rat brain (cerebellum) into urea and thus, may lead to formation of putrescine, the precursor of polyamine synthesis . In addition, while agmatine can inhibit brain nitric oxide synthase, it did not serve as a substrate for nitric oxide formation. J Biol Chem, 1996 Jul 26, 271(30), 17609 - 12 Developmental and tissue-specific expression of mouse pelle-like protein kinase; Trofimova M et al.; The NF-kappaB/c-Rel proteins are a family of evolutionarily conserved transcription factors activated during development that in the adult, mediate many processes including the immune response . A high degree of sequence similarity is shared between the NF-kappaB/c-Rel family of transcription factors and the Drosophila Dorsal protein as well as between its cytoplasmic inhibitor, IkappaBalpha, and the Drosophila Cactus protein . Genetic analyses of Dorsal have defined components of a signaling pathway for Dorsal activation, including a serine/threonine kinase, Pelle, placed upstream of Dorsal and Cactus . We demonstrate that this pathway is likely to be conserved in mammals by the isolation of a cDNA that encodes a novel mouse protein highly related to Pelle, mPLK (mouse Pelle-like protein kinase) . Expression of mPLK mRNA is developmentally regulated in the mouse and in adult tissue mPLK expression is greatest in the liver, a tissue that expresses a high level of NF-kappaB . Recombinant mPLK produced in bacteria is a protein kinase capable of autophosphorylating and phosphorylating IkappaBalpha. Biochem Biophys Res Commun, 1996 Jul 25, 224(3), 611 - 8 Nitrite reductase from Desulfovibrio desulfuricans (ATCC 27774)--a heterooligomer heme protein with sulfite reductase activity; Pereira IC et al.; The membrane bound cytochrome c nitrite reductase from the sulfate reducer Desulfovibrio desulfuricans (ATCC 27774) was found to have a high specific activity in the reduction of sulfite, producing stoichiometric amounts of sulfide . The K(m) for sulfite in the MV+.:sulfite oxidoreductase assay is 0.75 mM, and the specific activity 2.06 mumolH2/min/mg . Visible and EPR spectroscopies studies indicate that the enzyme high-spin heme reacts with sulfite in the oxidised state, and that sulfide partially reduces the enzyme . The redoxcycled enzyme, using H2/Hydrogenase/MV+ . as a reductant, is identical to the resting enzyme . This is the first time that a c-type nitrite reductase has been shown to reduce sulfite . These findings, besides revealing a new function for the nitrite reductase, raise a major question regarding the sulfur metabolism in the sulfate reducing bacteria as well as the cellular localization of the enzymatic activities involved in the dissimilatory reduction of sulfate . The purified nitrite reductase is a heterooligomer, containing two types of subunits of 62 kDa (+/- 5 kDa) and 18.8 kDa (+/- 1 kDa), and forms a complex or aggregate with a molecular mass of approximately 750 kDa. Biochemistry, 1996 Jul 23, 35(29), 9584 - 93 Functional interaction of the c-Myc transactivation domain with the TATA binding protein: evidence for an induced fit model of transactivation domain folding; McEwan IJ et al.; c-Myc is a member of a family of sequence specific-DNA binding proteins that are thought to regulate the transcription of genes involved in normal cell growth, differentiation, and apoptosis . In order to understand how human c-myc functions as a transcription factor, we have studied the mechanism of action and structure of the N-terminal transactivation domain, amino acids 1-143 . In a protein interaction assay, c-myc1-143 bound selectively to two basal transcription factors, the TATA binding protein (TBP) and the RAP74 subunit of TFIIF . Furthermore, the isolated c-myc transactivation domain competed for limiting factors required for the assembly of a functional preinitiation complex . This squelching of basal transcription was reversed in a dose-dependent manner by recombinant TBP . Taken together, these results identify TBP as an important target for the c-myc transactivation domain, during transcriptional initiation . Similar to other transactivation domains, the c-myc1-143 polypeptide showed little or no evidence of secondary structure, when measured by circular dichroism spectroscopy (CD) in aqueous solution . However, significant alpha-helical conformation was observed in the presence of the hydrophobic solvent trifluoroethanol . Strikingly, addition of TBP caused changes in the CD spectra consistent with induction of protein conformation in c-myc1-143 during interaction with the target factor . This change was specific for TBP as a similar effect was not observed in the presence of TFIIB . These data support a model in which target factors induce or stabilize a structural conformation in activator proteins during transcriptional transactivation. FEBS Lett, 1996 Jul 22, 390(2), 119 - 23 The emergence of major cellular processes in evolution; Ouzounis C et al.; The phylogenetic distribution of divergently related protein families into the three domains of life (archaea, bacteria and eukaryotes) can signify the presence or absence of entire cellular processes in these domains and their ancestors . We can thus study the emergence of the major transitions during cellular evolution, and resolve some of the controversies surrounding the evolutionary status of archaea and the origins of the eukaryotic cell . In view of the ongoing projects that sequence the complete genomes of several Archaea, this work forms a testable prediction when the genome sequences become available . Using the presence of the protein families as taxonomic traits, and linking them to biochemical pathways, we are able to reason about the presence of the corresponding cellular processes in the last universal ancestor of contemporary cells . The analysis shows that metabolism was already a complex network of reactions which included amino acid, nucleotide, fatty acid, sugar and coenzyme metabolism . In addition, genetic processes such as translation are conserved and close to the original form . However, other processes such as DNA replication and repair or transcription are exceptional and seem to be associated with the structural changes that drove eukaryotes and bacteria away from their common ancestor . There are two major hypotheses in the present work: first, that archaea are probably closer to the last universal ancestor than any other extant life form, and second, that the major cellular processes were in place before the major splitting . The last universal ancestor had metabolism and translation very similar to the contemporary ones, while having an operonic genome organization and archaean-like transcription . Evidently, all cells today contain remnants of the primordial genome of the last universal ancestor. J Biol Chem, 1996 Jul 19, 271(29), 17330 - 4 Molecular cloning of human phosphomevalonate kinase and identification of a consensus peroxisomal targeting sequence; Chambliss KL et al.; Two overlapping cDNAs which encode human liver phosphomevalonate kinase (PMKase) were isolated . The human PMKase cDNAs predict a 191-amino acid protein with a molecular weight of 21,862, consistent with previous reports for mammalian PMKase (Mr = 21,000-22,500) . Further verification of the clones was obtained by expression of PMKase activity in bacteria using a composite 1024-base pair cDNA clone . Northern blot analysis of several human tissues revealed a doublet of transcripts at approximately 1 kilobase (kb) in heart, liver, skeletal muscle, kidney, and pancreas and lower but detectable transcript levels in brain, placenta, and lung . Analysis of transcripts from human lymphoblasts subcultured in lipid-depleted sera (LDS) and LDS supplemented with lovastatin indicated that PMKase gene expression is subject to regulation by sterol at the level of transcription . Southern blotting indicated that PMKase is a single copy gene covering less than 15 kb in the human genome . The human PMKase amino acid sequence contains a consensus peroxisomal targeting sequence (PTS-1), Ser-Arg-Leu, at the C terminus of the protein . This is the first report of a cholesterol biosynthetic protein which contains a consensus PTS-1, providing further evidence for the concept that early cholesterol and nonsterol isoprenoid biosynthesis may occur in the peroxisome. Biochim Biophys Acta, 1996 Jul 18, 1275(1-2), 16 - 20 Respiratory chains of archaea and extremophiles; Schafer G et al.; Extremophilic organisms are adapted to harsh environmental conditions like high temperature, extremely acidic or alkaline pH, high salt, or a combination of those . With a few exceptions extremophilic bacteria are colonizing only moderately hot biotopes, whereas hyperthermophiles are found specifically among archaea (formerly 'archaebacteria') which can thrive at temperatures close to or even above the boiling point of water . It has been a challenging question whether the special properties of their proteins and membranes have been acquired by adaptation, or whether they might reflect early evolutionary states as suggested by their phylogenetic position at the lowest branches of the universal tree of life. Biochem Biophys Res Commun, 1996 Jul 16, 224(2), 555 - 63 Interferon-gamma-dependent expression of inducible nitric oxide synthase, interleukin-12, and interferon-gamma-inducing factor in macrophages elicited by allografted tumor cells; Sanchez-Bueno A et al.; We have examined the mechanisms of activation of macrophages (Mos) induced by i.p . allografted Meth A tumor cells (Meth A-Mos) during the rejection of the cells by C57BL/6 mice . Inducible nitric oxide (NO) synthase (iNOS), interleukin-12 (IL-12), and interferon-gamma (IFN-gamma)-inducing factor (IGIF) were transiently expressed in Meth A-Mos during the rejection . The expression was impaired in mice in which the gene encoding IFN-gamma had been disrupted (IFN-gamma-/-) . In vitro studies showed that Meth A-Mos from IFN-gamma +/+ mice induced an apoptotic type of cell death in P815 cells, without cell-to-cell contact, in an NO-dependent manner, whereas Meth A-Mos from IFN-gamma-/- mice could not lyse these cells . The iNOS, IL-12, and IGIF expression was also impaired in bacteria-activated Mos from IFN-gamma-/-mice, indicating that IFN-gamma, but not IGIF, would be the initial signal that leads to the activation of Mos in vivo. J Immunol, 1996 Jul 15, 157(2), 650 - 5 Introduction of exogenous antigens into the MHC class I processing and presentation pathway by Drosophila antennapedia homeodomain primes cytotoxic T cells in vivo; Schutze-Redelmeier MP et al.; The homeodomain of the Antennapedia molecule (AntpHD) spontaneously crosses cellular membranes and can be used to deliver up to 50 additional amino acids to the cytoplasm . We exploited this approach to deliver antigenic peptides to the MHC class I processing and presentation pathway . AntpHD-based fusion peptides expressing the 170-179 HLA-Cw3 CTL epitope (pCw3) were produced in bacteria . Incubation of these fusion peptides with H-2d target cells resulted in efficient delivery to the cytosol as indicated by protease resistance and confocal microscopy . Moreover, this introduction of an exogenous Ag resulted in sensitization of the cell to lysis by a CTL clone specific for the 170-179 HLA-Cw3-derived peptide . Sensitivity of the Ag processing to brefeldin A but not to chloroquine is consistent with the delivery of AntpHD fusion peptides to the conventional class I-associated processing pathway . Immunization of DBA/2 (H-2d) mice with AntpHD pCw3 fusion peptide in the presence of SDS primed H-2Kd-restricted HLA-Cw3-specific CTL . Similar results were obtained with AntpHD fusion peptides expressing the 147-156 influenza nucleoprotein peptide . The strategy outlined in this paper provides a new approach for introducing molecules into the MHC class I Ag-presenting pathway . This approach has clear relevance to the design of synthetic peptide-based vaccines. Biochem Pharmacol, 1996 Jul 12, 52(1), 35 - 42 Differential effects of tenidap on the zymosan- and lipopolysaccharide-induced expression of mRNA for proinflammatory cytokines in macrophages; Bondeson J et al.; Tenidap is a novel antirheumatic drug that combines cyclooxygenase inhibition with cytokine modulating qualities . We demonstrate here that tenidap inhibits the zymosan-induced expression of both interleukin 1 and tumor necrosis factor alpha in macrophages, at the mRNA and protein levels . The concentration-dependence of the tenidap-induced inhibition of the expression of mRNA for these proinflammatory cytokines agrees with that of its inhibitory effects on zymosan-induced arachidonate mobilization and changes in phosphoprotein pattern . The effects of tenidap on the lipopolysaccharide-induced expression of these cytokines are more complex . Tenidap inhibits the induction of interleukin 1 by lipopolysaccharide or bacteria, but less potently than the interleukin 1-response induced by zymosan . In contrast, the drug markedly potentiates the lipopolysaccharide-induced expression of tumor necrosis factor alpha at both the mRNA and protein levels . The latter effect is demonstrated to be due to cyclooxygenase inhibition and is reversed by prostaglandin E2. Proc Natl Acad Sci U S A, 1996 Jul 9, 93(14), 7131 - 6 Double-strand break repair in the absence of RAD51 in yeast: a possible role for break-induced DNA replication; Malkova A et al.; In wild-type diploid cells of Saccharomyces cerevisiae, an HO endonuclease-induced double-strand break (DSB) at the MAT locus can be efficiently repaired by gene conversion using the homologous chromosome sequences . Repair of the broken chromosome was nearly eliminated in rad52delta diploids; 99% lost the broken chromosome . However, in rad51delta diploids, the broken chromosomes were repaired approximately 35% of the time . None of these repair events were simple gene conversions or gene conversions with an associated crossover, instead, they created diploids homozygous for the MAT locus and all markers in the 100-kb region distal to the site of the DSB . In rad51delta diploids, the broken chromosome can apparently be inherited for several generations, as many of these repair events are found as sectored colonies, with one part being repaired and the other part being lost the broken chromosome . Similar events occur in about 2% of wild-type cells . We propose that a broken chromosome end can invade a homologous template in the absence of RAD51 and initiate DNA replication that may extend to the telomere, 100 or more kb away . Such break-induced replication appears to be similar to recombination-initiated replication in bacteria. Res Microbiol, 1996 Jul-Sep, 147(6-7), 489 - 93 Cra and the control of carbon flux via metabolic pathways; Ramseier TM; The catabolite repressor-activator (Cra) protein controls the direction of carbon flux through metabolic pathways in enteric bacteria . Cra binds to the control regions of target genes and exerts a negative effect on the expression of genes encoding glycolytic and Entner-Doudoroff enzymes, while exerting a positive effect on genes encoding Krebs cycle, glyoxylate shunt and gluconeogenic enzymes . Cra mediates cyclic AMP-independent catabolite repression of positively Cra-regulated genes and catabolite activation of negatively Cra-controlled genes. Res Microbiol, 1996 Jul-Sep, 147(6-7), 448 - 55 Evolution of carbohydrate metabolic pathways; Romano AH et al.; Current studies of hyperthermophilic archaea and bacteria, the phylogenetically deepest-rooted and slowest-evolving extant organisms known, are allowing new insights into the nature of presumably ancient metabolic pathways . The apparent common occurrence of modified non-phosphorylated Entner-Doudoroff (ED) pathways among saccharolytic archaea and the absence of the conventional Embden-Meyerhof-Parnas (EMP) mode of glycolysis indicate that the ED pathway is the older route of carbohydrate dissimilation . However, gluconeogenesis via the "reversed" EMP route has been found in archaea . Thus, the EMP pathway was probably an anabolic pathway to begin with; its catabolic role came later, with the evolution of fructose phosphate kinases, using ATP, ADP or pyrophosphate as phosphate donors . Similarly, the presence of reductive reactions of the citric acid cycle in anaerobic archaea and the most deeply rooted bacteria, including autotrophs, indicates that the citric acid cycle was originally a reductive biosynthetic pathway. Lijec Vjesn, 1996 Jul-Aug, 118(7-8), 178 - 83 {Sphingolipids--a new group of lipid second messengers?}; Mesaric M; Sphingolipids have the potential to regulate cell behavior at essentially all levels of signal transduction . They serve as cell surface receptors for cytoskeletal proteins, immunoglobulins, and some bacteria; as modifiers of the properties of cell receptors for growth factors (and perhaps other agents); and as activators and inhibitors of protein kinases, ion transporters, and other proteins . the biological activity of these compounds resides not only in the more complex molecules, but also in their turnover products . Since sphingolipids change with cell growth, differentiation, and neoplastic transformation, they could be vital participants in the regulation of these processes. Indian J Lepr, 1996 Jul-Sep, 68(3), 217 - 22 Cellularity of macrophage granuloma and morphological index; Porichha D et al.; In the present study, morphological index (MI) and average macrophage count per microscopic field in skin sections of 94 lepromatous (LL) patients is correlated . The subjects included 14 cases with some histoid features . The MI in the lepromatous cases varied from less than one to 40 and the corresponding macrophage counts ranged from 40 to 156 . In cases with histoid changes the MI varied from 30 to 60 and the cell count ranged from 215 to 360 . The histoid cases showed a higher MI and cell count compared to the other lepromatous cases . There was a positive correlation between MI and macrophage count and the hypercellular state appears to depend on living and multiplying bacteria. Hepatogastroenterology, 1996 Jul-Aug, 43(10), 796 - 9 Sequential changes of bile contents in patients with obstructive jaundice from different etiologies; Chen CY et al.; BACKGROUND/AIMS: The decreasing of serum concentration of bilirubin and the ability of hepatocytes to excrete various biliary contents after release of obstructive jaundice are good indicators of recovery of liver function . We conducted this study to clarify whether different causes of obstructive jaundice have different effects on the biliary excretion and how they are different when obstruction is released . PATIENTS AND METHODS: Fifteen patients with obstructive jaundice undergoing percutaneous transhepatic catheter drainage or endoscopic nasobiliary drainage were classified into two groups, depending on the cause of obstruction: common bile duct stones (n = 7) and biliary tract tumors (n = 8) . All patients in the gallstone group presented with acute cholangitis while only three patients in the tumor group had a positive bacteria culture in bile . Fasting biles were collected on the day of catheter placement and the 2nd, 4th, 6th, 8th, 10th day thereafter . The sequential changes of biliary concentration of bilirubin, phospholipid, cholesterol, bile salts and serum bilirubin were checked and compared between the two groups . RESULTS: The difference in the improvement of jaundice between the stone and tumor group (p > 0.05) were not significant, nor were the excretion of biliary contents after relief of obstruction . The reduction of serum bilirubin paralleled with the increased excretion of biliary bile salts and bilirubin (gamma = -0.51, p < 0.01 and gamma = -0.4, p < 0.05) in tumor group, but not in the stone group . CONCLUSIONS: The decrease of serum bilirubin and the sequential changes of bile contents after relief of obstruction are quite similar in stone and tumor induced obstructive jaundice. Avian Dis, 1996 Jul-Sep, 40(3), 572 - 5 Respiratory coccidiosis (Cryptosporidium baileyi) among northern Georgia broilers in one company; Goodwin MA et al.; Cryptosporidium baileyi causes respiratory disease in chickens . The purposes of this prospective study were to determine the incidence of C . baileyi tracheitis among broilers in a commercial setting, and the relationship between C . baileyi tracheitis and production performance parameters . All samples came from 56 farms that grow broilers for one company in northern Georgia . Tracheas were collected and examined with a light microscope and cultured for viruses and bacteria . Overall, 23 of 56 (41%) broiler flocks had C . baileyi tracheitis . Parasitism rates among C . baileyi-infected flocks ranged from a low of 10% to a high of 60% . Cryptosporidium baileyi tracheitis was very highly correlated (rho = 0.81, n = 56, P < 0.00001) to severity of tracheitis, negatively correlated (rho = -0.27, n = 56, P < 0.04) with average body weight, and correlated with airsacculitis (rho = 0.30, n = 56, P < 0.03) and condemnations (rho = 0.27, n = 56, P < 0.05) . The present study indicates that C . baileyi infection rates are high, and the role that this parasite plays in the pathogenesis of respiratory disease and production losses could be unexpectedly large. Nutrition, 1996 Jul-Aug, 12(7-8), 529 - 33 Oral arginine supplementation in acute liver injury; Adawi D et al.; Acute liver failure is accompanied by a high rate of bacterial and septic complications . Arginine has a potent effect on the immune system and modulates bacterial clearance in septic models . We studied the effect of oral arginine supplementation on the extent of liver injury and the associated bacterial translocation in an acute liver injury model in rats . Sprague-Dawley rats were divided into normal, liver injury, and arginine supplemented groups . In the arginine group, 2% arginine was supplemented daily through a nasogastric tube for 8 d . Acute liver injury was induced on the eighth day by intraperitoneal injection of D-galactosamine (1.1 g/kg body wt) . Samples were collected 24 h after the liver injury . In the arginine-supplemented group, alkaline phosphatase, bilirubin, and aspartate aminotransferase were reduced significantly compared with the acute liver injury control group . The results of bacterial translocation in the arginine-supplemented group showed a significantly reduced number of translocated bacteria to the liver and mesenteric lymph nodes than occurred in the acute liver injury group . The histological study of the liver in arginine-supplemented group showed scattered areas of hepatocellular necrosis and inflammatory cell infiltration, and in the acute liver injury group there were more and widespread hepatocellular necrosis and inflammatory cell infiltration . Oral supplementation of arginine in an acute liver injury model improves significantly the state of the liver injury and reduces bacterial translocation to the liver and mesenteric lymph nodes. Immunobiology, 1996 Jul, 195(2), 199 - 208 The proliferation of human T lymphocytes stimulated by Helicobacter pylori antigens; Chmiela M et al.; Fractionated mononuclear cells (MNCs) were obtained from peripheral blood of healthy human volunteers, seronegative for H . pylori antibodies . The MNCs were stimulated in culture with whole live or heat-killed H . pylori cells or with bacterial cell surface (SA) or cytoplasmic (CA) antigens . There was a marked proliferative response of T cells in cultures stimulated with 10(5) cells/well of live H . pylori, 5 micrograms/well of CA or 5-20 micrograms/well of SA . However, no proliferation was observed in MNC cultures containing higher "doses" of live H . pylori organisms (10(7)/well) or CA (20 micrograms/well) . Moreover, higher "doses" of the bacteria or CA entirely inhibited the response of T cells to PHA. Glycobiology, 1996 Jul, 6(5), 543 - 50 Characterization of two mannose-binding protein cDNAs from rhesus monkey (Macaca mulatta): structure and evolutionary implications; Mogues T et al.; Mannose-binding proteins (MBPs), members of the collectin family, have been implicated as lectin opsonins for various viruses and bacteria . Two distinct but related MBPs, MBP-A and MBP-C, with approximately 55% identity at the amino acid level, have been previously characterized from rodents . In humans, however, only one form of MBP has been characterized . In this paper we report studies elucidating the evolution of primate MBPs . ELISA and Western blot analyses indicated that rhesus and cynomolgus monkeys have two forms of MBP in their sera, while chimpanzees have only one form, similar to humans . Two distinct MBP cDNA clones were isolated and characterized from a rhesus monkey liver cDNA library . Rhesus MBP-A is closely related to the mouse and rat MBP-A, showing 77% and 75% identity at the amino acid level, respectively . Rhesus MBP-A also has three cysteines at the N-terminus, similar to mouse and rat MBP-A and human MBP . Rhesus MBP-C shares 90% identity with the human MBP at the amino acid level and has three cysteines at the N-terminus, in contrast to two cysteine residues found in rodent MBP-C . A stretch of nine amino acids close to the N-terminus, absent in both mouse and rat MBP-A, but present in rodent MBP-C, chicken and human MBPs, is also found in the rhesus MBP-A . The phylogenetic analysis of rhesus and other mammalian MBPs, coupled with the serological data suggest that at least two distinct MBP genes existed prior to mammalian radiation and the hominoid ancestor apparently lost one of these genes or failed to express it. Curr Opin Rheumatol, 1996 Jul, 8(4), 296 - 308 HLA-B27 structure, function, and disease association; Lopez-Larrea C et al.; The polymorphism of HLA-B27 alleles is located in the peptide-anchoring motif . In recent years, fundamental insights have been made into the molecular aspects of HLA-B27-restricted presentation . Subtle differences in peptide binding fine specificity are especially interesting for closely related HLA-B27 alleles that have differential association with ankylosing spondylitis . Bacterial infection has been suggested to play a role in the pathogenesis of HLA-B27-associated disease . Remarkable progress has been made in identifying peptides derived from bacteria that can be presented by HLA-B27 . Despite the mechanisms proposed to explain B27-associated diseases, there are no clear correlations between peptide sequence, differential binding to B27 subtypes, and recognition by peptide-specific T cell receptors . Furthermore, new transgenic models have now been developed that we hope will allow a clearer view of the function of B27 and the mechanisms involved in the pathogenesis of spondyloarthropathies. Curr Opin Rheumatol, 1996 Jul, 8(4), 275 - 87 The sacroiliac joint in the spondyloarthropathies; Braun J et al.; The term spondyloarthropathy (SpA) describes and defines a group of related inflammatory joint disease that share characteristic clinical features and a unique association with the major histocompatibility complex class I molecule HLA-B27 . Five subgroups can be differentiated: ankylosing spondylitis, reactive arthritis, psoriatic arthritis, arthritis associated with inflammatory bowel disease, and undifferentiated SpA . The sacroiliac joints are centrally involved in the SpA, most clearly and pathognomonic in ankylosing spondylitis, in which most patients are affected early in the disease . Overcoming some of the diagnostic difficulties of early sacroiliitis, dynamic magnetic resonance imaging was shown to visualize both acute and chronic changes in the sacroiliac joints . The inflammation in the sacroiliac joints in patients with SpA was recently examined in more detail; using immunohistology and in situ hybridrization, T cells, macrophages, and various cytokines were found in infiltrates . Biopsy specimens were obtained under guided computed tomography, and in the same study, intra-articular corticosteroid treatment was successfully undertaken . Further investigation of such biopsy specimens showed the absence of DNA of reactive arthritis-associated bacteria . The pathogenesis of the SpA and the reason for the tropism for the sacroiliac joints is still obscure . The nature of the relation of the genetic background of SpA to initially triggering bacterial infections remains to be established . In chronic disease, autoimmune mechanisms might be more important. Gen Pharmacol, 1996 Jul, 27(5), 761 - 71 Salivary mucins in oral mucosal defense; Slomiany BL et al.; 1 . Salivary mucins are well recognized as an important factor in the preservation of the health of the oral cavity . These large glycoproteins play a major role in the formation of protective coatings covering tooth enamel and oral mucosa, which act as a dynamic functional barrier capable of modulating the untoward effects of oral environment, and are of significance to the processes occurring within the epithelial perimeter of mucosal defense . 2 . Based on macromolecular characteristics, the mucins in saliva fall into high (> 1000 kDa) and low (200-300 kDa) molecular weight forms . The two forms, although differ with respect to bacterial clearance ability, display virtually identical carbohydrate chain make-up, ranging in size from 3 to 16 sugar units . 3 . Of the two mucin forms, the low molecular weight form more efficient in bacterial aggregation, predominates in saliva and oral mucosal mucus coat of caries-resistant individuals, while the level of the high molecular weight form is higher in caries-susceptible subjects . The saliva of caries-resistant individuals also exhibits greater activity of protease capable of conversion of the high molecular weight mucin to the low molecular weight form . 4 . The bacterial aggregating activity of salivary mucins appears to be associated with sulfomucins rather than sialomucins . While the removal of sialic acid causes only partial loss in mucin aggregating capacity, a complete loss in the bacterial aggregating activity occurs following mucin desulfation . 5 . The mucins in oral mucosal mucus coat interact with the epithelial surfaces through specific membrane receptors . This interaction apparently involves the carbohydrate moiety of mucin molecule and may be rendered vulnerable to disruption by opportunistic bacteria colonizing the oral mucosa . 6 . Salivary sulfo- and sialomucins actively participate in the modulation of the oral mucosal calcium channel activity through the inhibition of EGF-stimulated channel protein tyrosine phosphorylation . This function of salivary mucins is of paramount importance to mucosal calcium homeostasis. J Clin Gastroenterol, 1996 Jul, 23(1), 11 - 4 Uncertain clinical significance of duodenal mucosal abnormalities in HIV-infected individuals . Results of a case-control study; Rabeneck L et al.; Previous research has described abnormalities of duodenal mucosal morphology in human immunodeficiency virus (HIV)-infected individuals . We wanted to determine the frequency of disturbed villus architecture and investigate its relationship to HIV-related chronic diarrhea . We conducted a case-control study of 120 HIV-infected men, 63 with and 57 without chronic diarrhea . Stools were cultured for bacteria and examined for ova and parasites; esophagogastroduodenoscopy and flexible sigmoidoscopy with mucosal biopsies were performed . Biopsy tissue was examined using light and electron microscopy to detect enteric pathogens and to evaluate mucosal morphology . The mean CD4+ cell count was 143/min3, and enteric pathogens were detected in 56 of 120 men (47%) . In approximately half the study sample (57%), duodenal villus architecture was normal; complete villus flattening was not observed . We detected no association between chronic diarrhea and altered villus architecture . Although further study is needed to clarify the pathogenesis of altered duodenal mucosal morphology, our results suggest that the clinical significance of the abnormalities may be small. Trends Microbiol, 1996 Jul, 4(7), 286 - 90 The molecular ecology of legionellae; Fields BS; Legionella pneumophila is the most highly characterized member of a genus of bacteria that survive as intracellular parasites of freshwater protozoa . These bacteria can also multiply intracellularly in human phagocytic cells and cause respiratory disease in humans . Comparison of the invasive strategies of L . pneumophila in mammalian and protozoan cells and study of the interactions between Legionella and protozoa should prove useful in development of strategies for the prevention of legionellosis. Vet Microbiol, 1996 Jul, 51(1-2), 69 - 76 Detection of Mycoplasma mycoides subspecies mycoides by monoclonal antibody-based sandwich ELISA; Rodriguez F et al.; Monoclonal antibodies (MAbs) were produced from a mouse immunised with Mycoplasma mycoides subsp . mycoides small colony (MmmSC) antigen and their use to detect and differentiate strains within the Mycoplasma mycoides cluster investigated in an antigen capture ELISA format . The MAbs produced could not distinguish between MmmSC and M . mycoides subsp . mycoides large colony (MmmLC) strains . However, the sandwich ELISAs developed were able to specifically distinguish these two biotypes from the other four members of the M . mycoides cluster, and from all other mycoplasma or bacteria species examined . The most sensitive application of the test was a combination of enrichment and capture by overnight or 48-h incubations of samples inoculated into mycoplasma broth in antibody-coated microtiter wells. Scand J Gastroenterol, 1996 Jul, 31(7), 671 - 7 Gastric emptying and first-pass metabolism of ethanol in elderly subjects with and without atrophic gastritis; Pedrosa MC et al.; BACKGROUND: Oral ethanol intake results in lower blood ethanol concentrations than intravenous administration of the same dose of ethanol . This first-pass metabolism is thought to be due to gastric metabolism of ethanol via alcohol dehydrogenase and also to hepatic first-pass metabolism . METHODS: Since a loss of gastric mucosa may decrease first-pass metabolism of ethanol, this metabolism was studied in 10 elderly subjects (6 women and 4 men) with atrophic gastritis and bacterial overgrowth and in 17 control subjects with normal gastric secretory function . Atrophic gastritis was verified by means of the serum pepsinogen I to pepsinogen II ratio and the hypochlorhydria occurring after pentagastrin stimulation . Bacterial overgrowth was assessed by bacteria . In addition, gastric emptying rates of ethanol solution with technetium-99m sulfur colloid were calculated from scintigraphic images . Furthermore, gastric biopsy specimens were taken from 12 female patients with atrophic gastritis and from 12 controls for determination of alcohol dehydrogenase activity . RESULTS: Neither gender (female versus male, 28 +/- 5% versus 42 +/- 5%), atrophic gastritis (normal versus atrophic gastritis, 35 +/- 4% versus 32 +/- 6%), nor tetracycline treatment in atrophic gastritis subjects (before versus after, 32 +/- 6% versus 41 +/- 5%) had a statistically significant effect on the first-pass metabolism of ethanol in the elderly . Gastric alcohol dehydrogenase activity was significantly lower in atrophic gastritis subjects than in controls (p < 0.01) . A significant correlation was found between the first-pass metabolism of ethanol in healthy controls and gastric half-emptying time (p = 0.032) . CONCLUSIONS: We conclude from these data that the rate of gastric emptying modulates first-pass metabolism of ethanol in elderly individuals. Protein Sci, 1996 Jul, 5(7), 1342 - 54 Cytochrome c3 from Desulfovibrio gigas: crystal structure at 1.8 A resolution and evidence for a specific calcium-binding site; Matias PM et al.; Crystals of the tetraheme cytochrome c3 from sulfate-reducing bacteria Desulfovibrio gigas (Dg) (MW 13 kDa, 111 residues, four heme groups) were obtained and X-ray diffraction data collected to 1.8 A resolution . The structure was solved by the method of molecular replacement and the resulting model refined to a conventional R-factor of 14.9% . The three-dimensional structure shows many similarities to other known crystal structures of tetraheme c3 cytochromes, but it also shows some remarkable differences . In particular, the location of the aromatic residues around the heme groups, which may play a fundamental role in the electron transfer processes of the molecule, are well conserved in the cases of hemes I, III, and IV . However, heme II has an aromatic environment that is completely different to that found in other related cytochromes c3 . Another unusual feature is the presence of a Ca2+ ion coordinated by oxygen atoms supplied by the protein within a loop near the N-terminus . It is speculated that this loop may be stabilized by the presence of this Ca2+ ion, may contribute to heme-redox perturbation, and might even be involved in the specificity of recognition with its redox partner. Biotechniques, 1996 Jul, 21(1), 82 - 6 Application of 5-bromo-2'deoxyuridine as a label for in situ hybridization in chromosome microdissection and painting, and 3' OH DNA end labeling for apoptosis; Muhlmann-Diaz MC et al.; We have utilized 5-bromo-2'deoxyuridine (BrdU) substituted DNA as a probe for a number of applications including, principally, for chromosome painting by fluorescence in situ hybridization (FISH) but also for DNA end-labeling to detect apoptotic cell death and for filter hybridization . Br-dUTP was used as a substitute for biotin or digoxigenin-dUTP in probe labeling techniques, such as random priming, nick translation, end-labeling or PCR . An especially useful application is that it may be incorporated into probe DNA while cells or plasmids in bacteria are growing in the presence of BrdU . This can be particularly advantageous when large quantities of probe are needed, since the cost per mole of digoxigenin-dUTP or biotin-dUTP is nearly 1000 times that of Br-dUTP . Also, if probe is prepared by growth in BrdU, the difference in cost to prepare equal quantities of labeled DNA is more than 10,000 times greater for biotin-dUTP. Z Naturforsch {C}, 1996 Jul-Aug, 51(7-8), 493 - 9 Lactarane type sesquiterpenoids as inhibitors of leukotriene biosynthesis and other, new metabolites from submerged cultures of Lentinellus cochleatus (Pers . ex Fr.) Karst; Wunder A et al.; Three known sesquiterpenoids of the lactarane and secolactarane type, deoxylactarorufin A (1), blennin A (2) and blennin C (3), have been obtained from cultures of Lentinellus cochleatus (Basidiomycetes) together with the new metabolites (Z)-2-chloro-3-(4-methoxyphenyl)-2-propen-1-ol (4) and lentinellone (5), a protoilludane derivative . The structures were determined by spectroscopic investigations . 1, 2 and 3 are potent inhibitors of leukotriene biosynthesis in rat basophilic leukemia (RBL-1) cells and human peripheral blood leukocytes (PBL). Clin Microbiol Rev, 1996 Jul, 9(3), 382 - 404 Detection of infection or infectious agents by use of cytologic and histologic stains; Woods GL et al.; A wide variety of stains are useful for detection of different organisms or, for viruses, the cytopathologic changes they induce, in smears prepared directly from clinical specimens and in tissue sections . Other types of stains, such as hematoxylin and eosin, are used routinely to stain tissue sections and are most valuable for assessing the immunologic response of the host to the invading pathogen . In many cases, the pattern of inflammation provides important clues to diagnosis and helps to guide the selection of additional "special" stains used predominantly for diagnosis of infectious diseases . A stain may be nonspecific, allowing detection of a spectrum of organisms, as do the Papanicolaou stain and silver impregnation methods, or detection of only a limited group of organisms, as do the different acid-fast techniques . Some nonspecific stains, such as the Gram stain, are differential and provide valuable preliminary information concerning identification . Immunohistochemical stains, on the other hand, are specific for a particular organism, although in some cases cross-reactions with other organisms occur . Despite the wealth of information that can be gleaned from a stained smear or section of tissue, however, the specific etiology of an infection often cannot be determined on the basis of only the morphology of the organisms seen; culture data are essential and must be considered in the final diagnosis. Chem Biol, 1996 Jul, 3(7), 519 - 24 Accommodating structurally diverse peptides in proteins; Wilkinson AJ; Many peptide-binding proteins must bind numerous ligands that differ in size, sequence and sometimes orientation . A variety of strategies for coping with structurally diverse peptide ligands have been revealed by biochemical and structural studies of proteins with roles in immunity, transport and signal transduction. Clin Diagn Lab Immunol, 1996 Jul, 3(4), 423 - 8 High-dose catecholamine treatment decreases polymorphonuclear leukocyte phagocytic capacity and reactive oxygen production; Wenisch C et al.; Flow cytometry was used to study phagocytic function (uptake of fluorescein isothiocyanate-labeled bacteria) and release of reactive oxygen products (dihydrorhodamine 123 converted to rhodamine 123) following phagocytosis by neutrophil granulocytes of heparinized whole blood treated with adrenaline, noradrenaline, dopamine, dobutamine, or orciprenaline . Reduced neutrophil phagocytosis and reactive oxygen production were seen at 12 micrograms of adrenaline per liter (72% each compared with control values); at 120 micrograms of noradrenaline (72% each), dobutamine (83 and 80%, respectively), and orciprenaline (81 and 80%, respectively) per liter; and at 100 micrograms of dopamine per liter (66 and 70%) (P < 0.05 for all) . At these dosages, neutrophil chemotaxis was reduced to < 50% of control values for all catecholamines . Treatment with catecholamines at lower dosages had no significant effect on phagocytosis or generation of reactive oxygen products or chemotaxis . The phagocytic capacity of granulocytes was related to the generation of reactive oxygen products (r = 0.789; P < 0.05) . The results demonstrate that catecholamines have a suppressive effect on the response of phagocytic cells to bacterial pathogens at high therapeutic levels in blood. Plant Mol Biol, 1996 Jul, 31(4), 721 - 30 The cyanobacterium Synechococcus sp . PCC 7942 possesses a close homologue to the chloroplast ClpC protein of higher plants; Clarke AK et al.; The Clp family consists of large, ubiquitous proteins that function as molecular chaperones and/or regulators of ATP-dependent proteolysis . A single copy gene coding for one of these proteins, ClpC, was cloned from the unicellular cyanobacterium Synechococcus sp . PCC 7942 . The predicted polypeptide is most similar (ca . 88%) to the chloroplast-localized ClpC protein from higher plants . Using degenerate PCR primers specific for the two distinct ATP-binding domains characteristic of all ClpA-C proteins, partial sequences homologous to clpC from Synechococcus were also identified in five other cyanobacterial strains . The Synechococcus clpC gene is transcribed under standard growth conditions as a monocistronic message of around 2.7 kb . The level of this message, however, decreases slightly after a shift from 37 to 47.5 degrees C for 2 h, similar to expression previously observed for clpC mRNA from heat-shocked higher plants . At the protein level, the amount of ClpC remains relatively unchanged during the high temperature shift, while that of the known heat shock protein GroEL rises considerably . In contrast, the constitutive level of ClpC in Synechococcus increases considerably under conditions of rapid growth, both with increasing light intensities or CO2 concentrations . This, and the fact that attempts to inactivate clpC expression fail to produce a viable phenotype, suggest that ClpC activity is essential for growth in this obligate photoautotrophic cyanobacterium. Biomaterials, 1996 Jul, 17(13), 1273 - 7 Microwave plasmas for low-temperature dry sterilization; Chau TT et al.; The use of microwave plasmas for dry sterilization has been investigated . The dry-sterilization process is a process similar to plasma etching . Bacteria and viruses can be killed by chemical reactions which disintegrate their bodies and remove them from the surface to be sterilized . The removal of bacteria or viruses from material surfaces is caused by the reaction of activated oxygen species in the plasma with hydrocarbon bonds of the cell wall of the bacteria or the capsid of the viruses . Preliminary experiments indicate that the low-temperature dry sterilization method is easy to use, requires much less time than other methods for sterilization, and is also non-toxic . It is feasible for use in the field of sterilization in dental and medical clinics. FASEB J, 1996 Jul, 10(9), 979 - 85 Vitamin A and retinoids in antiviral responses; Ross AC et al.; Vitamin A deficiency results in multiple derangements that impair the response to infection . This review focuses on experimental models of specific virus infections and on cytokines and cells with cytolytic activity important to antiviral defenses . Altered specific antibody responses and greater epithelial damage in vitamin A-deficient hosts are consistent findings . The cytolytic activity of natural killer cells and various cytokine responses are altered . The inflammatory response to infection may also result in derangements in the transport and metabolism of retinol . We speculate that interaction of several factors may combine to explain the greater severity of infection seen in vitamin A-deficient animals and children . In addition to a preexisting lack of tissue vitamin A, these factors may include reduced mobilization and increased excretion of retinol during the acute phase response to infection, poor innate and specific immune response to virus, and delayed repair of damaged epithelia . Foci of vitamin A-deficient epithelia may be sites of penetration of bacteria and other agents, leading to secondary infections and contributing to an increased severity of infections and poor outcome in vitamin A-deficient animals and humans. Kansenshogaku Zasshi, 1996 Jul, 70(7), 673 - 80 {Subserogrouping of 49 Legionella pneumophila serogroup 1 strains with monoclonal antibodies by slide latex agglutination method and its usefulness for epidemiologic study}; Gondaira F et al.; Legionella pneumophila serogroup (SG) 1 has been known as a most frequent and important causative bacteria of Legionella pneumonia . It was reported that antigenicity of the serogroup was composed by numerous antigenic factors . To study antigenic factor formula of Japanese isolates from both clinical and environmental sources together with Philadelphia 1 strain, we examined slide latex agglutination system with monoclonal antibodies for subsergorouping . Philadelphia 1 and GIFU10102 strain (environmental isolate) were used as immune strains based on a cross absorption test result by rabbit antisera . Five anti L . pneumophia SG1 monoclonal antibody-producing clones were established . All monoclonal antibodies were SG1 specific but showed different reactivities with strain to strain . We prepared monoclonal antibody sensitized latex and used for subserogrouping of isolated strains . Twenty-two clinical isolates from Legionella pneumonia patients and 26 environmental isolates were examined . Each strain was reacted with at least one of the 5 sensitized latex and its antigenic formula was designed by sensitized latex reaction pattern . As a total of 6 patterns demonstrated in clinical isolates and 7 patterns in environmental isolates, 48 L . pneumophila SG1 isolates were divided into 11 subserogroup patterns . The antigenic formula of Philadelphia 1 was same as one of clinical isolate patterns . It was considered that this subserogrouping system would be a useful tool for epidemiologic study. Arch Dis Child Fetal Neonatal Ed, 1996 Jul, 75(1), F49 - 52 CRIB (clinical risk index for babies) in relation to nosocomial bacteraemia in very low birthweight or preterm infants; Fowlie PW et al.; Positive blood cultures in very low birthweight or preterm infants usually reflect bacteraemia, septicaemia, or failure of asepsis during sampling and lead to increased costs and length of stay . Rates of nosocomial, or hospital acquired, bacteraemia may therefore be important indicators of neonatal unit performance, if comparisons are adjusted for differences in initial risk . In a preliminary study the risk of nosocomial bacteraemia was related to initial clinical risk and illness severity measured by the clinical risk index for babies (CRIB) . Nosocomial bacteraemia was defined as clinically suspected infection with culture of bacteria in blood more than 48 hours after birth . One or more episodes of nosocomial bacteraemia were identified retrospectively in 36 of 143 (25%) infants in a regional neonatal unit between 1992 and 1994 . Biologically plausible models were developed using regression analysis techniques . After correcting for period at risk, nosocomial bacteraemia was independently associated with gestation at birth and CRIB . Death was independently associated with CRIB, but not with nosocomial bacteraemia . CRIB may contribute, with other explanatory variables, to more comprehensive predictive models of death and nosocomial infection . These may facilitate future risk adjusted comparative studies between groups of neonatal units. Int J Syst Bacteriol, 1996 Jul, 46(3), 811 - 3 Sanguibacter inulinus sp . nov; Pascual C et al.; Six strains of coryneform bacteria were isolated from blood samples obtained from healthy cows . Phenotypic and molecular genetic studies showed that these isolates represent a new species of the genus Sanguibacter, for which the name Sanguibacter inulinus is proposed . The type strain of S . inulinus is strain ST-50 (= NCFB 3024). Appl Environ Microbiol, 1996 Jul, 62(7), 2201 - 11 Full-scale studies of factors related to coliform regrowth in drinking water; LeChevallier MW et al.; An 18-month survey of 31 water systems in North America was conducted to determine the factors that contribute to the occurrence of coliform bacteria in drinking water . The survey included analysis of assimilable organic carbon (AOC), coliforms, disinfectant residuals, and operational parameters . Coliform bacteria were detected in 27.8% of the 2-week sampling periods and were associated with the following factors: filtration, temperature, disinfectant type and disinfectant level, AOC level, corrosion control, and operational characteristics . Four systems in the study that used unfiltered surface water accounted for 26.6% of the total number of bacterial samples collected but 64.3% (1,013 of 1,576) of the positive coliform samples . The occurrence of coliform bacteria was significantly higher when water temperatures were > 15 degrees C . For filtered systems that used free chlorine, 0.97% of 33,196 samples contained coliform bacteria, while 0.51% of 35,159 samples from chloraminated systems contained coliform bacteria . The average density of coliform bacteria was 35 times higher in free-chlorinated systems than in chloraminated water (0.60 CFU/100 ml for free-chlorinated water compared with 0.017 CFU/100 ml for chloraminated water) . Systems that maintained dead-end free chlorine levels of < 0.2 mg/liter or monochloramine levels of < 0.5 mg/liter had substantially more coliform occurrences than systems that maintained higher disinfectant residuals . Free-chlorinated systems with AOC levels greater than 100 micrograms/liter had 82% more coliform-positive samples and 19 times higher coliform levels than free-chlorinated systems with average AOC levels less than 99 micrograms/liter . Systems that maintained a phosphate-based corrosion inhibitor and limited the amount of unlined cast iron pipe had fewer coliform bacteria . Several operational characteristics of the treatment process or the distribution system were also associated with increased rates of coliform occurrence . The study concludes that the occurrence of coliform bacteria within a distribution system is dependent upon a complex interaction of chemical, physical, operational, and engineering parameters . No one factor could account for all of the coliform occurrences, and one must consider all of the parameters described above in devising a solution to the regrowth problem. Plant Cell, 1996 Jul, 8(7), 1121 - 35 Identification of the major starch synthase in the soluble fraction of potato tubers; Marshall J et al.; The major isoform of starch synthase from the soluble fraction of developing potato tubers has been purified and used to prepare an antibody and isolate a cDNA . The protein is 140 kD, and it is distinctly different in predicted primary amino acid sequence from other isoforms of the enzyme thus far described . Immunoinhibition and immunoblotting experiments and analysis of tubers in which activity of the isoform was reduced through expression of antisense mRNA revealed that the isoform accounts for approximately 80% of the activity in the soluble fraction of the tuber and that it is also bound to starch granules . Severe reductions in activity had no discernible effect on starch content or amylose-to-amylopectin ratio of starch in tubers . However, they caused a profound change in the morphology of starch granules, indicative of important underlying changes in the structure of starch polymers within the granule. FEMS Microbiol Lett, 1996 Jul 1, 140(2-3), 171 - 8 Attempts to characterize the mechanisms involved in the growth inhibition of Mycobacterium microti in interferon-gamma or tumor necrosis factor-alpha activated J774A.1 cells; Gupta R et al.; The growth of Mycobacterium microti was inhibited within J774A.1 macrophage cells activated with either interferon-gamma or tumor necrosis factor-alpha . Activation with interferon-gamma or tumor necrosis factor-alpha alone did not stimulate the production of nitrite in J774A.1 cells . Interferon-gamma but not tumor necrosis factor-alpha increased the production of hydrogen peroxide in a concentration dependent manner but scavengers of reactive oxygen species did not influence the growth inhibiting effect of interferon-gamma within J774A.1 cells . Both interferon-gamma and tumor necrosis factor-alpha enhanced the fusion of M . microti containing phagosomes with lysosomes and the ultimate degradation of bacteria . Our results showed that growth inhibition of M . microti within interferon-gamma or tumor necrosis factor-alpha stimulated J774A.1 cells was independent of reactive oxygen intermediate and reactive nitrogen intermediate production. J Bacteriol, 1996 Jul, 178(14), 4143 - 9 Coexistence of two structurally similar but functionally different PII proteins in Azospirillum brasilense; de Zamaroczy M et al.; The coexistence of two different PII, proteins in Azospirillum brasilense was established by comparing proteins synthesized by the wild-type strain and two null mutants of the characterized glnB gene (encoding PII) adjacent to glnA . Strains were grown under conditions of nitrogen limitation or nitrogen excess . The proteins were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) or isoelectric focusing gel electrophoresis and revealed either by {32P}phosphate or {3H}uracil labeling or by cross-reaction with an anti-A . brasilense PII-antiserum . After SDS-PAGE, a single band of 12.5 kDa revealed by the antiserum in all conditions tested was resolved by isoelectric focusing electrophoresis into two bands in the wild-type strain, one of which was absent in the glnB null mutant strains . The second PII protein, named Pz, was uridylylated under conditions of nitrogen limitation . The amino acid sequence deduced from the nucleotide sequence of the corresponding structural gene, called glnZ, is very similar to that of PII . Null mutants in glnB were impaired in regulation of nitrogen fixation and in their swarming properties but not in glutamine synthetase adenylylation . No glnZ mutant is yet available, but it is clear that PII and Pz are not functionally equivalent, since glnB null mutant strains exhibit phenotypic characters . The two proteins are probably involved in different regulatory steps of the nitrogen metabolism in A . brasilense. Physiol Rev, 1996 Jul, 76(3), 839 - 85 Oxygen sensing and molecular adaptation to hypoxia; Bunn HF et al.; This review focuses on the molecular stratagems utilized by bacteria, yeast, and mammals in their adaptation to hypoxia . Among this broad range of organisms, changes in oxygen tension appear to be sensed by heme proteins, with subsequent transfer of electrons along a signal transduction pathway which may depend on reactive oxygen species . These heme-based sensors are generally two-domain proteins . Some are hemokinases, while others are flavohemoproteins {flavohemoglobins and NAD(P)H oxidases} . Hypoxia-dependent kinase activation of transcription factors in nitrogen-fixing bacteria bears a striking analogy to the phosphorylation of hypoxia inducible factor-1 (HIF-1) in mammalian cells . Moreover, redox chemistry appears to play a critical role both in the trans-activation of oxygen-responsive genes in unicellular organisms as well as in the activation of HIF-1 . In yeast and bacteria, regulatory operons coordinate expression of genes responsible for adaptive responses to hypoxia and hyperoxia . Similarly, in mammals, combinatorial interactions of HIF-1 with other identified transcription factors are required for the hypoxic induction of physiologically important genes. J Forensic Sci, 1996 Jul, 41(4), 612 - 6 Postmortem stability of cocaine and cocaethylene in blood and tissues of humans and rabbits; Moriya F et al.; A study was conducted to examine the postmortem stability of cocaine and cocaethylene in rabbit blood and tissues, and to determine whether cocaethylene is produced in decomposed human specimens containing cocaine and endogenous ethanol . Heart blood, liver, brain and femoral muscle taken from rabbits 20 min after oral administration of 20 mg/kg cocaine together with 2 g/kg ethanol were kept at 20-25 degrees C for 5 days . Cocaine and cocaethylene concentrations were in the order brain > liver > muscle > blood, and showed very large intersubject variations at the time of death . Cocaine was degraded rapidly in the blood and liver . However, 12.0 +/- 8.5% and 26.2% +/- 19.4% of the original cocaine was still detectable in the brain and muscle, respectively . Cocaethylene was degraded more slowly than cocaine in all of the specimens . The pH of the blood remained around 7.4 during a 5-day period; all the other specimens showed pH values of 6.2-6.7 on and after the first day postmortem . When 10,000 ng/g cocaine was incubated with decomposed human blood, liver, brain and muscle homogenates containing 0.29-0.60 mg/g endogenous ethanol at 20-25 degrees C and 37 degrees C, no change in cocaine concentration was observed during the study period of 24 h, and no cocaethylene was detected . The pH values of the homogenates were within the range 4.2 to 5.2 at the beginning of the experiment . It was found that: 1) cocaethylene was more stable in postmortem specimens than cocaine; 2) muscle as well as brain was specimen of choice for detecting cocaine and cocaethylene postmortem; 3) cocaine was resistant to decomposition under acidic conditions; and 4) putrefactive bacteria had no ability to produce cocaethylene even in the presence of cocaine and endogenous ethanol. Mol Biol Evol, 1996 Jul, 13(6), 719 - 34 Molecular biology and evolution of resistance of toxicants; Taylor M et al.; To the prevailing biochemical/physiological classification of mechanisms of organismal resistance to toxicants, an additional molecular dimension is proposed . Predictions are developed regarding the relative prevalence of different classes of mutations and are found to compare favorably with reports from the literature . In particular, point mutations in target loci were the dominant form of resistance for both lab and field selection . Amplifications of target loci were less common than structural mutations, and more common for lab-selected than for field-selected strains . Amplification was the most common mechanism of up-regulation of metabolizing enzymes . In comparison, only one mutation involving cis-regulation and several involving trans-acting regulation were found . Mutations involving gene disruption and down-regulation were uncommon, but were found in appropriate cases, i.e., when toxicants stimulated rather than inhibited target function and when metabolizing enzymes converted toxicants into more toxic metabolites . Additional phenomena of likely but uncertain importance are genetic "succession," recombinational limitation, and negative cross-resistance . More work on these phenomena and on quantification of fitness costs of resistance is recommended. J Invest Dermatol, 1996 Jul, 107(1), 108 - 12 Dermatophytes contain a novel lipid-like leukocyte activator; Kahlke B et al.; In the early phase of dermatophytosis, neutrophils are regularly detected microscopically in the infected skin . Although neutrophil recruitment may at least in part occur indirectly by complement activation, we asked whether dermatophytes might release chemoattractants for neutrophils . We cultivated various strains of different dermatophytes and tested fungal extracts for the presence of neutrophil chemotactic activity . As a result, we detected neutrophil chemotactic activity only in diethylether extracts, but not in aqueous extracts . We purified this lipid-like leukocyte activator (LILA) to apparent homogeneity by reversed-phase high performance liquid chromatography and found that purified LILA does not show ultraviolet absorption at wavelengths > 210 nm . Biologic studies revealed that LILA is as effective as formyl-methionyl-leucyl-phenylalanine in eliciting neutrophil chemotaxis, degranulation, and activation of the respiratory burst . Desensitization experiments in chemotaxis and degranulation with leukotriene B4, platelet-activating factor, or 5-oxo-eicosanoids revealed that LILA does not cross-desensitize with any of these other lipid-like attractants and thus possibly acts via a distinct as yet postulated neutrophil receptor . It is hypothesized that LILA, similarly to formylated methionyl peptides in bacteria, represents a dermatophyte- and possibly fungus-specific lipid compound that allows the host phagocytes to specifically recognize fungal infection . This system would be similar to the recognition of bacteria by phagocytes via N-formylated methionyl peptides, which represent a characteristic and unique system to identify bacteria. Kyobu Geka, 1996 Jul, 49(8 Suppl), 646 - 51 {Surgical treatment of infective endocarditis}; Matsubayashi K et al.; From 1981 to 1996, 48 consecutive patients, aged range 1 to 72 years, underwent surgical treatment for infective endocarditis . The infection was in the aortic valve in 10 patients, the mitral valve in 17, the aortic and mitral valves in 7, mixed aortic, mitral and tricuspid valves in one, the tricuspid valve in 9, the pulmonary valve in 3, and the other in 2, thirty-seven patients had native valve endocarditis (NVE) of which 22 cases were in the active stage . Seven cases had active prosthetic valve endocarditis (PVE) and 4 had VSD patch infection . The overall hospital mortality rate was 14.6% (7/48) . The hospital mortality rate of NVE was 2.7% (1/37) and that of active NVE was 4.5% (1/22) . That of PVE was 71.4% (5/7) and one of 4 cases with VSD patch infection was lost, so the mortality rate of the prosthetic material infection was 54.5% (6/11) . Only 1 patient required reoperation for persistent infection . There were 2 late deaths caused by noncardiac disease . Thirty-nine of the total IE patients are now survived . These data demonstrate excellent results in patient with NVE undergoing the surgical treatment at the early phase, and support the premise that patients with active PVE should have also early surgical intervention. Infect Immun, 1996 Jul, 64(7), 2657 - 65 The major fimbrial subunit of Bordetella pertussis binds to sulfated sugars; Geuijen CA et al.; Bordetella pertussis fimbriae are composed of major and minor subunits, and recently it was shown that the minor fimbrial subunit binds to Vla-5, a receptor located on monocytes (W . Hazenbos, C . Geuijen, B . van den Berg, F . Mooi, and R . van Furth, J . Infect . Dis . 171:924-929, 1995) . Here we present evidence that the major subunits bind to sulfated sugars, which are ubiquitous in the respiratory tract . Binding was observed to chondroitin sulfate, heparan sulfate, and dextran sulfate but not to dextran . Removal of the minor subunit from fimbriae did not significantly affect binding to sulfated sugars, indicating that the major subunit alone is sufficient for this binding . Fimbriae were also able to bind HEp-2 cells, which are known to display glycoconjugates on their surface . This binding was not dependent on the presence of the minor subunit . However, binding was dependent on the sulfation state of the glycoconjugates, since inhibition of the sulfation resulted in a significant reduction of fimbria binding . The specificity of fimbria binding was further characterized by using heparan sulfate-derived disaccharides in inhibition assays . Two disaccharides were highly effective inhibitors, and it was observed that both the degree of sulfation and the arrangement of the sulfate groups on the disaccharides were important for binding to fimbriae . B . pertussis bacteria also bound to sulfated sugars and HEp-2 cells, and analysis of B . pertussis mutants indicated that both filamentous hemagglutinin and fimbriae were required for this binding . A host protein present in the extracellular matrix, fibronectin, has binding activities similar to those of B . pertussis fimbriae, binding to both Vla-5 and sulfated sugars . Two regions in the major fimbrial subunit were identified which showed similarity with fibronectin peptides which bind to sulfated sugars . Thus, B . pertussis fimbriae exemplify molecular mimicry and may co-opt host processes by mimicking natural ligand-receptor interactions. Infect Immun, 1996 Jul, 64(7), 2643 - 8 Acidic pH changes receptor binding specificity of Helicobacter pylori: a binary adhesion model in which surface heat shock (stress) proteins mediate sulfatide recognition in gastric colonization; Huesca M et al.; The gastric pathogen helicobacter pylori is one of a number of bacteria which bind specifically to gangliotetraosylceramide, gangliotriaosylceramide, and phosphatidylethanolamine in vitro at neutral pH . Since this organism encounters an acid pH during initial infection of the stomach, we have monitored the effect of pH on receptor binding specificity and found induction of specific binding to sulfoglycolipids (sulfatide) following brief treatment at low pH . We have previously shown that heat shock proteins (hsps) bind to sulfatide, and the suspicion that this was a stress-induced response is supported by the fact that a similar change in H . pylori binding specificity was observed if the organisms were briefly exposed to heat shock treatment . Following the stress stimulus, the change in glycolipid binding specificity was prevented by the inclusion of inhibitors of protein synthesis or by incubation with anti-hsp antibodies . Expression of hsps in the surface extract and surface reactivity with anti-hsp antibodies correlated with the change in glycolipid binding specificity . Despite the presence of high levels of H . pylori cell surface urease activity which may neutralize the microenvironmental pH, the acid-induced change in binding specificity was enhanced in the presence of urea . These studies suggest that cell surface hsps mediate sulfatide recognition by this organism under stress conditions . A binary receptor model is proposed for gastric colonization by H . pylori. Infect Immun, 1996 Jul, 64(7), 2585 - 94 Identification of Legionella pneumophila mutants that have aberrant intracellular fates; Swanson MS et al.; After uptake by macrophages, Legionella pneumiophila evades phagosome-lysosome fusion and replicates in a compartment associated with the endoplasmic reticulum . A collection of bacterial mutants defective for growth in macrophages were isolated, and the intracellular fate of each mutant strain was analyzed by fluorescence microscopy . To measure intracellular replication, bacteria inside macrophages were stained with the DNA dye 4',6-diamidino-2-phenylindole (DAPI) . Evasion of the endocytic pathway was quantified by immunofluorescence localization of lp120 {correction of IgpI20} (LAMP-1), a membrane protein of late endosomes and lysosomes, or by measuring colocalization of bacteria with a fluorescent tracer, Texas red-ovalbumin, preloaded into lysosomes . Replication vacuoles were quantified by immunofluorescence localization of BiP, an endoplasmic reticulum protein . By these approaches, four phenotypic groups of mutants were classified . One class formed replication vacuoles less efficiently than the wild type did; another formed replication vacuoles, but replication was abortive; in another class, most phagosomes containing bacteria acquired markers of the endocytic pathway but a minority formed replication vacuoles and the bacteria replicated; finally, a fourth class, the one most defective for intracellular growth, occupied vacuoles that acquired markers of the endocytic pathway. Infect Immun, 1996 Jul, 64(7), 2449 - 56 Coinoculation with Hartmannella vermiformis enhances replicative Legionella pneumophila lung infection in a murine model of Legionnaires' disease; Brieland J et al.; The effect of inhaled amoebae on the pathogenesis of Legionnaires' disease was investigated in vivo . A/J mice, which are susceptible to replicative Legionella pneumophila infections, were inoculated intratracheally with L . pneumophila (10(6) bacteria per mouse) or were coinoculated with L . pneumophila (10(6) bacteria per mouse) and Hartmannella vermiformis (10(6) amoebae per mouse) . The effect of coinoculation with H . vermiformis on bacterial clearance, histopathology, cellular recruitment into the lung, and intrapulmonary levels of cytokines including gamma interferon and tumor necrosis factor alpha was subsequently assessed . Coinoculation with H . vermiformis significantly enhanced intrapulmonary growth of L . pneumophila in A/J mice . Histopathologic and flow cytometric analysis of lung tissue demonstrated that while A/J mice inoculated with L . pneumophila alone develop multifocal pneumonitis which resolves with minimal mortality, mice coinoculated with H . vermiformis develop diffuse pneumonitis which is associated with diminished intrapulmonary recruitment of lymphocytes and mononuclear phagocytic cells and significant mortality . Furthermore, coinoculation of mice with H . vermiformis resulted in a fourfold enhancement in intrapulmonary levels of gamma interferon and tumor necrosis factor alpha compared with mice infected with L . pneumophila alone . The effect of H . vermiformis on intrapulmonary growth of L . pneumophila in a resistant host (i.e., BALB/c mice) was subsequently evaluated . While BALB/c mice do not develop replicative L . pneumophila infections following inoculation with L . pneumophila alone, there was an eightfold increase in intrapulmonary L . pneumophila in BALB/c mice coinoculated with H . vermiformis . These studies, demonstrating that intrapulmonary amoebae potentiate replicative L . pneumophila lung infection in both a susceptible and a resistant host, have significant implications with regard to the potential role of protozoa in the pathogenesis of pulmonary diseases due to inhaled pathogens and in the design of strategies to prevent and/or control legionellosis. Biochem J, 1996 Jul 1, 317 ( Pt 1), 147 - 55 Purification and characterization of assimilatory nitrite reductase from Candida utilis; Sengupta S et al.; Nitrate assimilation in many plants, algae, yeasts and bacteria is mediated by two enzymes, nitrate reductase (EC 1.6.6.2) and nitrite reductase (EC 1.7.7.1) . They catalyse the stepwise reduction of nitrate to nitrite and nitrite to ammonia respectively . The nitrite reductase from an industrially important yeast, Candida utilis, has been purified to homogeneity . Purified nitrite reductase is a heterodimer and the molecular masses of the two subunits are 58 and 66 kDa . The native enzyme exhibits a molecular mass of 126 kDa as analysed by gel filtration . The identify of the two subunits of nitrite reductase was confirmed by immunoblotting using antibody for Cucurbita pepo leaf nitrite reductase . The presence of two different sized transcripts coding for the two subunits was confirmed by (a) in vitro translation of mRNA from nitrate-induced C . utilis followed by immunoprecipitation of the in vitro translated products with heterologous nitrite reductase antibody and (b) Northern-blot analysis . The 66 kDa subunit is acidic in nature which is probably due to its phosphorylated status . The enzyme is stable over a range of temperatures . Both subunits can catalyse nitrite reduction, and the reconstituted enzyme, at a higher protein concentration, shows an activity similar to that of the purified enzyme . Each of these subunits has been shown to contain a few unique peptides in addition to a large number of common peptides . Reduced Methyl Viologen has been found to be as effective an electron donor as NADPH in the catalytic process, a phenomenon not commonly seen for nitrite reductases from other systems. Dig Dis Sci, 1996 Jul, 41(7), 1337 - 45 Endoscopic-pathologic correlates of Candida esophagitis in acquired immunodeficiency syndrome; Wilcox CM et al.; Although Candida esophagitis is one of the most common opportunistic infections in patients with acquired immunodeficiency syndrome (AIDS), there has been no systematic study of the endoscopic and pathologic manifestations of this disease . During a 53-month period, 141 patients with AIDS and Candida esophagitis were studied . All patients had the severity of esophagitis graded prospectively and esophageal mucosal biopsies performed . Tissue biopsies were evaluated for histologic evidence of ulceration, extent of candidiasis, and presence of viral cytopathic effect . Follow-up was obtained . There appeared to be a uniform endoscopic appearance; with increasing severity, the scattered mucosal plaques coalesced, resulting in circumferential disease and luminal impingement . The pathologic pattern of Candida esophagitis was homogenous . Plaque material was composed primarily of desquamated superficial hyperplastic hyperkeratotic squamous epithelium and inflammatory cells, with infiltration by fungal elements and bacteria consistent with superinfection . Although endoscopic and histopathologic ulcer was commonly seen in these patients (32%), only four patients had ulcer believed secondary to Candida esophagitis alone . In conclusion, in patients with AIDS, Candida esophagitis is a superficial mucosal infection resulting in characteristic endoscopic and histopathologic patterns. J Bacteriol, 1996 Jul, 178(13), 3939 - 48 Caulobacter and Asticcacaulis stalk bands as indicators of stalk age; Poindexter JS et al.; The prosthecae (stalks) of dimorphic caulobacters of the genera Caulobacter and Asticcacaulis are distinguished among such appendages by the presence of disk-like components known as stalk bands . Whether bands are added to a cell's stalk(s) as a regular event coordinated with the cell's reproductive cycle has not been settled by previous studies . Analysis of the frequency of stalks with i, i + 1, i + 2, etc . bands 'among more than 7,000 stalks of Caulobacter crescentus revealed that in finite (batch) cultures (in which all offspring accumulate), the proportion of stalks with i + 1 hands was regularly 50% of the proportion of stalks with i bands . This implied that the number of bands correlated with the number of reproductive cycles completed by a stalked cell . In chemostat-maintained perpetual cultures, the proportion was greater than 50% because stalked cells, with their shorter reproductive cycle times, contributed a larger proportion of offspring to the steady-state population than did their swarmer siblings . In Asticcacaulis biprosthecum cells, which bear twin prosthecae, the twins on a typical cell possessed the same number of bands . For both genera, stalk bands provide a unique morphological feature that could be employed in an assessment of age distribution and reproductive dynamics within natural populations of these caulobacters. Am J Respir Crit Care Med, 1996 Jul, 154(1), 116 - 23 Mortality of nosocomial pneumonia in ventilated patients: influence of diagnostic tools; Timsit JF et al.; The overmortality induced by nosocomial infections, especially pneumonia in ventilated patients (VNP), is still a matter of controversy because it is difficult to know precisely the respective effects of VNP per se and both the underlying illness and the severity of the disease that indicates ICU stay . During a 3-yr period, for each patient mechanically ventilated for more than 48 h we recorded underlying illness, reason for mechanical ventilation, clinical and therapeutic data collected during the first 48 h of ventilation, and death in the ICU . Patients with suspicion of VNP (S-VNP) according to clinical, radiologic, and biologic criteria underwent bronchoscopy with protected specimen brush (PSB) and bronchoalveolar lavage culture (BAL-C) . VNP was confirmed (C-VNP) if PSB > or = 10(3) cfu/ml and/or BAL-C > or = 10(4) cfu/ml . Prognostic multivariate analysis was performed introducing S-VNP and C-VNP as time-dependent covariates . Of the 387 studied patients, 112 S-VNP and 56 C-VNP were observed with overall mortality of 43% (168 patients) . MacCabe, APACHE II score, shock, use of sedatives and absence of enteral nutrition were additively associated with an increased mortality as well as C-VNP (relative risk {RR}: 1.8, p = 0.007) . Nevertheless, when S-VNP and C-VNP were simultaneously introduced in the Cox model, only S-VNP remained associated with increased mortality . In patients suspected of VNP, confirmation of VNP using PSB and/or BAL-C adds no prognostic information . Whether this could be explained by the lack of sensitivity of protected distal samples or the severity of underlying conditions of S-VNP patients is still an open issue . A multivariate analysis based on follow-up data during the ICU course of ventilated patients will be initiated in the near future. Lett Appl Microbiol, 1996 Jul, 23(1), 9 - 12 Reduction of Brochothrix thermosphacta on beef surfaces following immobilization of nisin in calcium alginate gels; Cutter CN et al.; Lean and adipose beef carcass tissues inoculated with Brochothrix thermosphacta (BT) (approx . 4.50 log10 cfu cm-2) were left untreated (U) or treated with 100 micrograms ml-1 nisin (N), calcium alginate (A) or 100 micrograms ml-1 nisin immobilized in a calcium alginate gel (AN) . Tissue samples were refrigerated after treatments and bacterial populations and nisin activity were determined at 0, 1, 2 and 7 d . U, A and N treatments of lean and adipose tissues did not suppress bacterial growth ( > 6 log10 cfu cm-2 by day 7) while treatments of lean and adipose tissues with AN suppressed bacteria ( > 2.42 log10 cfu cm-2 by day 7) . Bacteriocin titres from both tissues were higher in AN vs N samples after the 7 d incubation . This study demonstrates that immobilization of nisin in a gel may be a more effective delivery system of a bacteriocin to the carcass surface than direct application. Lett Appl Microbiol, 1996 Jul, 23(1), 64 - 6 A selective medium for the isolation of Arcobacter from meats; de Boer E et al.; A method, including enrichment in Arcobacter Selective Broth (ASB) and isolation on semisolid Arcobacter Selective Medium (ASM) under aerobic conditions at 24 degrees C, is described for the isolation of Arcobacter from retail meat products . Selective agents used in ASB and ASM were cefoperazone, trimethoprim, piperacillin and cycloheximide . Arcobacters were isolated from 53 (24.1%) of 220 poultry meat products and also, at lower incidence from samples of beef and pork . The isolates were identified as A . butzleri or A . butzleri-like and belonged to a wide variety of serotypes and biotypes. J Virol, 1996 Jul, 70(7), 4724 - 8 Prion protein PrPc interacts with molecular chaperones of the Hsp60 family; Edenhofer F et al.; Prions mediate the pathogenesis of certain neurodegenerative diseases, including bovine spongiform encephalopathy in cattle and Creutzfeldt-Jakob disease in humans . The prion particle consists mainly, if not entirely, of PrPSc, a posttranslationally modified isoform of the cellular host-encoded prion protein (PrPc) . It has been suggested that additional cellular factors might be involved in the physiological function of PrPc and in the propagation of PrPSc . Here we employ a Saccharomyces cerevisiae two-hybrid screen to search for proteins which interact specifically with the Syrian golden hamster prion protein . Screening of a HeLa cDNA library identified heat shock protein 60 (Hsp60), a cellular chaperone as a major interactor for PrPc . The specificity of the interaction was confirmed in vitro for the recombinant proteins PrPc23-231 and rPrP27-30 fused to glutathione S-transferase with recombinant human Hsp60 as well as the bacterial GroEL . The interaction site for recombinant Hsp60 and GroEL proteins was mapped between amino acids 180 and 210 of the prion protein by screening with a set of recombinant PrPc fragments . The binding of Hsp60 and GroEL occurs within a region which contains parts of the putative alpha-helical domains H3 and H4 of the prion protein. J Acquir Immune Defic Syndr Hum Retrovirol, 1996 Jul, 12(3), 233 - 48 T-cell homeostasis, competition, and drift: AIDS as HIV-accelerated senescence of the immune repertoire; Mittler JE et al.; The observation that the density of CD8+ T-lymphocytes increases as the density of CD4+ T-cells declines in adult HIV-1/AIDS patients, together with evidence that the total density of T-cells is regulated (homeostasis) has led to the suggestion that competition between lineages, and classes of T-cells contributes to the pathology of HIV . We use a mathematical model of the interactions between populations of T-cells, HIV, and other parasites to explore the effects of T-cell homeostasis and competition on the progression to AIDS . We demonstrate that as a consequence of parasite-mediated T-cell replication, of competition within and between different T-cell clones, and random processes (T-cell drift), some CD4+ lineages will be represented by relatively few cells, dearths, and some lineages may be lost, leaving holes in the immune repertoire . By killing CD4+ T-lymphocytes, HIV accelerates the rate at which these dearths and holes accumulate and leads to an early breakdown of the immune control of HIV and other parasites, AIDS . When this model allows for intense, but not complete, competition between the CD4+ and CD8+ T-cell populations, it can account for most of the features of an HIV-1 infection in adults, including the gradual decline in CD4+ T-cell densities and concomitant increase in HIV density, as well as the variability in time from infection to AIDS and the decline in the time from infection to AIDS in older patients. J Med Microbiol, 1996 Jul, 45(1), 6 - 9 Heterogeneity of human intestinal spirochaetes demonstrated by one-dimensional polyacrylamide gel electrophoresis of proteins visualised by (35)S-methionine labelling and Coomassie blue staining; Barrett SP et al.; The relatedness of strains of a human intestinal spirochaete was investigated by comparison of electrophoretic protein profiles produced by Coomassie Blue staining of proteins separated by polyacrylamide gel electrophoresis (PAGE) of lysed organisms and by examination of autoradiographs following PAGE of lysed (35)S-methionine-labelled organisms . A wide diversity of strains was revealed by both techniques but clustering of strains was different by the two methods . These findings support the view that the human intestinal spirochaetes comprise a group of bacteria of considerable heterogeneity. J Biol Chem, 1996 Jun 28, 271(26), 15695 - 702 Identification of the spectrin subunit and domains required for formation of spectrin/adducin/actin complexes; Li X et al.; Adducin is an actin-binding protein that has been proposed to function as a regulated assembly factor for the spectrin/actin network . This study has addressed the question of the subunit and domains of spectrin required for formation of spectrin/adducin/actin complexes in in vitro assays . Quantitative evidence is presented that the beta-spectrin N-terminal domain plus the first two alpha-helical domains are required for optimal participation of spectrin in spectrin/adducin/actin complexes . The alpha subunit exhibited no detectable activity either alone or following association with beta-spectrin . The critical domains of beta-spectrin involved in complex formation were determined using recombinant proteins expressed in bacteria . The N-terminal domain (residues 1-313) of beta-spectrin associated with F-actin with a Kd of 26 microM, and promoted adducin binding to F-actin with half-maximal activation at 110 nM . Addition of the first alpha-helical domain (residues 1-422) lowered the Kdfor F-actin by 4-fold to 6 microM, but also reduced the capacity by 3-fold and had no effect on interaction with adducin . Further addition of the second alpha-helical domain (residues 1-528) did not alter binding to F-actin but resulted in a 2-fold increased activity in promoting adducin binding with half-maximal activation at 50 nM . Addition of up to eight additional alpha-helical domains (residues 1-1388) resulted in no further change in F-actin binding or association with adducin . These results demonstrate an unanticipated role of the first repeat of beta-spectrin in actin binding activity and of the second repeat in association with adducin/actin, and imply the possibility of an extended contact between adducin, spectrin, and actin involving several actin subunits. Biochem Biophys Res Commun, 1996 Jun 25, 223(3), 770 - 7 Anaerobic O-demethylations of methoxynaphthols, methoxyfuran, and fluoroanisols by Sporomusa ovata; Stupperich E et al.; In vitro experiments with 3,4-dimethoxybenzoate-induced Sporomusa enzymes a broad O-methyl ether cleavage capacity . The O-demethylase activity hydrolized the methyl-oxygen linkages of methoxynaphtholes of the heterocycles 2-methoxyfuran or 2-methoxythiophene as well as of several dimethoxy and monomethoxy aryls under anaerobic conditions . Also, fluoro and chloro substituents of anisoles enhanced the O-demethylation rate, indicating that an electron delocalized aromatic structure supported the methyl ether activation mechanism . Monomethoxy aromatics with additional chargeable groups, however, were less effectively transformed by the O-demethylase activity . No transformations into hydroxylated products occurred with 4-(trifluoromethoxy)benzyl alcohol, 4-(trifluoromethoxy)fluorobenzene, 2,5-dimethoxytetrahydrofuran, or alkyl-O-methyl ethers . The inert ethers did not affect the 3,4-dimethoxybenzoate metabolism . Ether activation or the following methyl transfer to the methyl acceptor tetrahydrofolate involved a prominent 31 kDa peptide from the cytoplasmic cell fraction, because this particular peptide was lacking in cells grown with methanol, betaine or fructose. FEBS Lett, 1996 Jun 24, 389(1), 96 - 101 Genomes with distinct function composition; Tamames J et al.; The functional composition of organisms can be analysed for the first time with the appearance of complete or sizeable parts of various genomes . We have reduced the problem of protein function classification to a simple scheme with three classes of protein function: energy-, information- and communication-associated proteins . Finer classification schemes can be easily mapped to the above three classes . To deal with the vast amount of information, a system for automatic function classification using database annotations has been developed . The system is able to classify correctly about 80% of the query sequences with annotations . Using this system, we can analyse samples from the genomes of the most represented species in sequence databases and compare their genomic composition . The similarities and differences for different taxonomic groups are strikingly intuitive . Viruses have the highest proportion of proteins involved in the control and expression of genetic information . Bacteria have the highest proportion of their genes dedicated to the production of proteins associated with small molecule transformations and transport . Animals have a very large proportion of proteins associated with intra- and intercellular communication and other regulatory processes . In general, the proportion of communication-related proteins increases during evolution, indicating trends that led to the emergence of the eukaryotic cell and later the transition from unicellular to multicellular organisms. FEBS Lett, 1996 Jun 24, 389(1), 25 - 31 A structural model for the membrane-integral domain of succinate: quinone oxidoreductases; Hagerhall C et al.; Many succinate:quinone oxidoreductases in bacteria and mitochondria, i.e . succinate:quinone reductases and fumarate reductases, contain in the membrane anchor a cytochrome b whose structure and function is poorly understood . Based on biochemical data and polypeptide sequence information, we show that the anchors in different organisms are related despite an apparent diversity in polypeptide and heme composition . A general structural model for the membrane-integral domain of the anchors is proposed . It is an antiparallel four-helix bundle with a novel arrangement of hexa-coordinated protoheme IX . The structure can be applied to a larger group of membrane-integral cytochromes of b-type and has evolutionary and functional implications. Sci Total Environ, 1996 Jun 21, 185(1-3), 125 - 49 The form and bioavailability of non-ionic organic chemicals in sewage sludge-amended agricultural soils; Beck AJ et al.; The application of sewage sludges to agricultural land may increase the concentrations of many toxic organic chemicals in soils which could have adverse effects on wildlife and human health if these compounds enter foodchains . Chlorobenzenes (CBs), polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) are amongst those compounds currently receiving most attention . The "form' in which these, and other organic chemicals, are present in soils and their potential to be lost by various processes including leaching, volatilisation and (bio)degradation is shown to be dependent on the physicochemical characteristics of the soil and sewage sludge, environmental conditions and the properties of the chemicals themselves . The distinction is made between those compounds that are labile, reversibly sorbed and irreversibly sorbed by sewage sludge-amended soils . The implications of the form in which the chemicals are present in soil for their "availability' to transfer from the soil to bacteria, fungi, earthworms, grazing livestock and food crops followed by the potential for further transfers, metabolism or bioaccumulation are discussed . The importance of the timing and method of sewage sludge application to soil on "form' and "availability' are also considered. J Clin Invest, 1996 Jun 15, 97(12), 2842 - 8 Altered cardiac troponin T in vitro function in the presence of a mutation implicated in familial hypertrophic cardiomyopathy; Lin D et al.; Familial hypertrophic cardiomyopathy (HCM) can be caused by dominant missense mutations in cardiac troponin T (TnT), alpha-tropomyosin, C-protein, or cardiac myosin heavy chain genes . The myosin mutations are known to impair function, but any functional consequences of the TnT mutations are unknown . This report describes the in vitro function of troponin containing an IIe91Asn mutation in rat cardiac TnT, corresponding to the HCM-causing Ile79Asn mutation in man . Mutant and wild-type TnT cDNAs were expressed in bacteria and the proteins purified and reconstituted with the other troponin subunits, the mutation had no effect on troponin's affinity for tropomyosin, troponin-induced binding of tropomyosin to actin, cooperative binding of myosin subfragment 1 to the thin filament, CA(2+)-sensitive regulation of thin filament-myosin subfragment 1 ATPase activity, or the CA2+ concentration dependence of this regulation . However, the mutation resulted in 50% faster thin filament movement over a surface coated with heavy meromyosin in in vitro motility assays . The increased sliding speed suggests an unexpected role for the amino terminal region of TnT in which this mutation occurs . The relationship between