TitleAbstractYear(sorted ascending)
purification and properties of an aminopeptidase from a protamine-degrading marine bacterium.a protamine-degrading marine bacterium was isolated from marine soil and identified as aeromonas salmonicida subsp. based on its taxonomical characteristics. an alanine-specific aminopeptidase, called aminopeptidase k, from an extract of the strain was purified and characterized. the aminopeptidase k was purified about 80-fold by fractionation with ammonium sulfate and column chromatography on qa-52 cellulose, phenyl superose and superose 12. the purified enzyme is composed of 6 subunits of 86 k ...19979255972
aeromonas hydrophila necrotizing fasciitis and gas gangrene in a diabetic patient on haemodialysis. 19979269663
immunization with bacterial antigens: furunculosis.although the nature of the antigens and the immune responses they elicit to achieve immunity to furunculosis are still not well defined, the currently available vaccines comprising a. salmonicida bacterins emulsified in oil adjuvants and delivered by intraperitoneal injection provide remarkably high levels of long-lasting protection. despite some concern over side-effects, these vaccines have been adopted by most atlantic salmon farmers over the last four years, transforming a situation where fu ...19979270839
immunization with bacterial antigens: infections with motile aeromonads.motile aeromonads are a heterogeneous group of organisms which are involved in a number of disease syndromes of warm water fish. they are commonly associated with bacterial haemorrhagic septicaemia, infectious dropsy, red mouth disease, ulcerative conditions etc. a variety of factors has been considered to be associated with virulence including haemolysins, proteases, surface array protein, acetylcholinesterase etc. we have studied the immune response of indian major carps to antigens of motile ...19979270842
adjuvants and immunostimulants for enhancing vaccine potency in fish.adjuvants combined with immunogens are effective enhancers of the immune response in fish. as in other animals, substances such as freund's complete and incomplete adjuvants, light oils and bacterial lipopolysaccharides have been shown to induce elevated antibody production when added to bacterins and administered to fish. light oil adjuvants are now used successfully with injectable bacterins of aeromonas salmonicida, and in multivalent fish vaccines where a. salmonicida is combined with yersin ...19979270854
strengths and weaknesses of different challenge methods.the development of effective fish vaccines is greatly dependent on reproducible standardised challenge methods. different test protocols involving bath exposure, intra-peritoneal and intra-muscular injection and co-habitation are all well described in the literature. ideally, to represent the many facets of infectious diseases in fish, a test challenge method should closely mimic natural exposure to the pathogen and ensure that immune mechanisms located in the body surfaces play their role. bath ...19979270858
vaccinated fish welfare: protection versus immunisation of fish involves a number of potentially harmful procedures like handling, anaesthesia or injection of more or less toxic substances. adjuvanted vaccines may cause inflammation, granuloma and pigmentation at the site of injection. intraperitoneal administration of oil-adjuvanted vaccines to atlantic salmon pre-smolts has occasionally resulted in impaired growth and reduced carcass quality. the consequences of such vaccination for fish welfare may therefore be questioned. with ...19979270866
vaccination strategies in freshwater salmonid aquaculture.the focus of this chapter is antibacterial vaccines. the main salmonid species in freshwater aquaculture is the rainbow trout. other salmonid species are produced on a limited scale. the most important bacterial fish diseases in european freshwater aquaculture are the rainbow trout fry syndrome-rtfs-(flavobacterium psychrophilum) and enteric redmouth disease-erm-(yersinia ruckeri) which are widespread and cause serious epizootics, while furunculosis (aeromonas salmonicida) is endemic, only givin ...19979270868
vaccination strategies in seawater cage culture of salmonids.successful vaccination depends both on the development of protective vaccines and their correct use. in addition to deciding which diseases to vaccinate against, the choice of the method, timing, and use of revaccination must be considered. in seawater culture of salmonids, vibriosis and furunculosis are the most important diseases against which to vaccinate in many parts of the world, while cold-water vibriosis is of great significance in atlantic salmon in some areas with low water temperature ...19979270869
functions of s-layers.although s-layers are being increasingly identified on bacteria and archaea, it is enigmatic that in most cases s-layer function continues to elude us. in a few instances, s-layers have been shown to be virulence factors on pathogens (e.g. campylobacter fetus ssp. fetus and aeromonas salmonicida), protective against bdellovibrio, a depository for surface-exposed enzymes (e.g. bacillus stearothermophilus), shape-determining agents (e.g. thermoproteus tenax) and nucleation factors for fine-grain m ...19979276929
safe poultry meat production in the next century.the revolutionary industrialisation of the poultry industry in the last 30 years has made the food poultry meat available for large groups of consumers. due to its nutritional, sensory and economical characteristics, poultry meat is by far the most popular animal food product world-wide. epidemiological reports, however, incriminate poultry meat as a source for outbreaks of human food poisoning. the organisms involved are salmonella spp., campylobacter spp. and, to a lesser extent, listeria mono ...19979276991
enhancement of the resistance of tilapia and grass carp to experimental aeromonas hydrophila and edwardsiella tarda infections by several polysaccharides.efficacies of eleven polysaccharides including bar (glycan extracted from barley), curdlan, dex (dextran sulfate), inulin, krestin, laminaran, levan, po (glycan extracted from pleurotus ostreatus), scleroglucan, yg (yeast glucan), and zymosan, in the protection of tilapia, tilapia aureus p., and grass carp, ctenopharyngodon idellus, against bacterial infections in vivo were examined. four glycans. namely, bar, krestin, scleroglucan, and zymosan were observed to significantly increase the surviva ...19979280393
quorum sensing in aeromonas hydrophila and aeromonas salmonicida: identification of the luxri homologs ahyri and asari and their cognate n-acylhomoserine lactone signal molecules.spent culture supernatants from both aeromonas hydrophila and aeromonas salmonicida activate a range of biosensors responsive to n-acylhomoserine lactones (ahls). the genes for a quorum sensing signal generator and a response regulator were cloned from each aeromonas species and termed ahyri and asari, respectively. protein sequence homology analysis places the gene products within the growing family of luxri homologs. ahyr and asar are transcribed divergently from ahyi and asai, respectively, a ...19979286976
identification and molecular characterization of two tandemly located flagellin genes from aeromonas salmonicida a449.two tandemly located flagellin genes, flaa and flab, with 79% nucleotide sequence identity were identified in aeromonas salmonicida a449. the fla genes are conserved in typical and atypical strains of a. salmonicida, and they display significant divergence at the nucleotide level from the fla genes of the motile species aeromonas hydrophila and aeromonas veronii biotype sobria. flaa and flab encode unprocessed flagellins with predicted mrs of 32,351 and 32,056, respectively. when cloned under th ...19979286979
[bactericidal activity determination of biseptine, combination of chlorhexidine, benzalkonium chloride and benzylic alcohol, on 124 hospital bacterial strains].biseptine is an antiseptic composed of chlorhexidine digluconate (chx), benzalkonium chloride (bc) and benzylic alcohol. minimal bactericidal concentrations (mbcs) of biseptine were determined on 124 clinical strains: 76 enterobacteriaceae, 16 other gram negative bacilli, (pseudomonas spp, aeromonas spp, haemophilus spp) and 32 gram positive bacteria (staphylococcus spp, streptococcus spp, listeria spp, bacillus cereus), using microdilution method, in comparison with hibitane champ. modal mbc of ...19979296082
the synthesis, secretion and role in virulence of the paracrystalline surface protein layers of aeromonas salmonicida and a. hydrophila.the s-layers of the aeromonas spp. studied to date are composed of identical protein subunits which are translocated across the cytoplasmic membrane, periplasm and outer membrane to the cell surface, where they are assembled and tethered to the cell via an interaction with the o-polysaccharide side chains of the lipopolysaccharide. aeromonas s-layers have the ability to bind a number of host factors such as fibronectin, laminin and vitronectin as well as providing resistance to serum killing and ...19979297815
risk assessment of opportunistic bacterial pathogens in drinking water.this study was undertaken to examine quantitatively the risks to human health posed by heterotrophic plate count (hpc) bacteria found naturally in ambient and potable waters. there is no clear-cut evidence that the hpc bacteria as a whole pose a public health risk. only certain members are opportunistic pathogens. using the four-tiered approach for risk assessment from the national academy of sciences, hazard identification, dose-response modeling, and exposure through ingestion of drinking wate ...19979297985
zn(ii) dependence of the aeromonas hydrophila ae036 metallo-beta-lactamase activity and stability.two zn2+ binding sites were found in the aeromonas hydrophila ae036 metallo-beta-lactamase. the affinity of the first binding site for zn2+ ions is so high that the dissociation constant could not be determined, but it is significantly lower than 20 nm. the mono-zn2+ form of the enzyme exhibits a maximum activity against its carbapenem substrates. the presence of a zn2+ ion in the second lower affinity binding site results in a loss of enzymatic activity with a ki value of 46 microm at ph 6.5. t ...19979298974
distribution and expression of beta-lactamase genes among aeromonas spp.clinical and environmental isolates of aeromonas spp. (20 aeromonas caviae, 33 aeromonas veronii and 21 aeromonas hydrophila) were examined for their ability to yield mutants derepressed for beta-lactamase production and for the distribution of the three chromosomally encoded beta-lactamase genes, amps and ceps from a. veronii bv. sobria and cpha from a. hydrophila. of these isolates, 100% and 96% of the isolates from a. hydrophila and a. caviae, respectively, yielded beta-lactamase derepressed ...19979301981
bacteriocin-like substance of aeromonas hydrophila. 19979302421
crystal structure at 1.2 a resolution and active site mapping of escherichia coli peptidyl-trna hydrolase.peptidyl-trna hydrolase activity from escherichia coli ensures the recycling of peptidyl-trnas produced through abortion of translation. this activity, which is essential for cell viability, is carried out by a monomeric protein of 193 residues. the structure of crystalline peptidyl-trna hydrolase could be solved at 1.2 a resolution. it indicates a single alpha/beta globular domain built around a twisted mixed beta-sheet, similar to the central core of an aminopeptidase from aeromonas proteolyti ...19979303320
microbiological evaluation of bottled uncarbonated mineral water in taiwan.the microbiological quality of 136 samples of bottled uncarbonated mineral water, including 88 domestic and 48 imported samples, was investigated. the numbers of samples with heterotrophic plate count (hpc) over the maximum level legally permitted in taiwan (200 colony forming units ml-1) were 45 (51.1%) and 29 (60.4%) for domestic and imported samples, respectively. coliforms and faecal streptococci were not detectable in the samples tested. two of the domestic samples were contaminated with ae ...19979310848
cleavage of influenza a virus h1 hemagglutinin by swine respiratory bacterial proteases.cleavage of influenza a virus hemagglutinin (ha) is required for expression of fusion activity and virus entry into cells. extracellular proteases are responsible for the proteolytic cleavage activation of avirulent avian and mammalian influenza viruses and contribute to pathogenicity and tissue tropism. the relative contributions of host and microbial proteases to cleavage activation in natural infection remain to be established. we examined 23 respiratory bacterial pathogens and 150 aerobic ba ...19979311838
[toxigenic vibrio cholerae: identification of the ctxb gene].a specific probe was designed to identify part of the genetic sequence of the ctxb gene which encodes for the b subunit of the cholera toxin by polymerase chain reaction (pcr) which amplifies a 318 bp segment of the ctxb gene. marked with p32, we used this probe for colony hybridization which is a technique for identifying the production capacity of subunit b of strains of vibrio cholerae o1 from different outbreaks in south america (perú 1992 and ecuador 1993-1995) and from, collection strains. ...19979312275
enterotoxicity, haemolytic activity and antibiotic susceptibility of aeromonas eucrenophila strains isolated from water and infected fish.strains of a. eucrenophila isolated from fresh water (2 strains) and infected fish (4 strains) were tested for haemolytic activity and enterotoxicity and any correlation between them. also, the resistance patterns of a. eucrenophila were tested especially in relation to ampicillin. none of the a. eucrenophila strains caused fluid accumulation in the initial tests, however, they did so only after one to four sequential passages through the gut of a susceptible host. all the strains of a. eucrenop ...19979315221
hyperproduction, purification, and mechanism of action of the cytotoxic enterotoxin produced by aeromonas hydrophila.a gene encoding the cytotoxic enterotoxin (act) from aeromonas hydrophila was hyperexpressed with the pet, ptrx, and pgex vector systems. maximum toxin yield was obtained with the ptrx vector. approximately 40 to 60% of act was in a soluble form with the ptrx and pet vector systems. the toxin protein was purified to homogeneity by a combination of ammonium sulfate precipitation and fast protein liquid chromatography-based column chromatographies, including hydrophobic, anion-exchange, sizing, an ...19979317040
differences in eicosanoid and cytokine production between injury/hemorrhage and bacteremic shock in the pig.plasma concentrations of the eicosanoids leukotriene (lt)b4, ltc4d4e4, thromboxane (tx)a2 and prostaglandin (pg)i2, and tumor necrosis factor (tnf) were measured during acute bacteremic shock and injury/hemorrhage in two porcine models. as txa2 and pgi2 are rapidly metabolized, we measured their stable metabolites txb2 and 6-keto-pgf1 alpha. bacteremic shock was induced by a graded infusion of aeromonas hydrophila over 4 h. injury/hemorrhage was produced by a 30 min, 30% total blood volume hemor ...19979329129
[post-traumatic endophthalmitis with multiple water pathogens].a 37-y-old worker for a recycling company suffered from a corneal perforation by a wire which had been in contact with dirt and moisture.19979333666
inclusion of aeromonas dna hybridization group 11 in aeromonas encheleia and extended descriptions of the species aeromonas eucrenophila and a. encheleia.the recently reported chemotaxonomic and genotypic description of two well-separated subgroups (i and ii) in aeromonas eucrenophila and their affiliation to aeromonas encheleia and the unnamed aeromonas dna hybridization group (hg) 11 (g. huys, m. altwegg, m.-l. hänninen, m. vancanneyt, l. vauterin, r. coopman, u. torck, j. lüthy-hottenstein, p. janssen, and k. kersters, syst. appl. microbiol. 19:616-623, 1996) has questioned the original species descriptions of a. eucrenophila and a. encheleia. ...19979336923
aeromonas popoffii sp. nov., a mesophilic bacterium isolated from drinking water production plants and reservoirs.we examined the taxonomic position of seven aeromonas isolates, recovered from flemish and scottish drinking water production plants and reservoirs, which were previously recognized by numerical analysis of genomic aflp fingerprints as members of an unknown aeromonas taxon that most closely resembled the species aeromonas bestiarum (dna hybridization group [hg] 2). the new phenotypic and dna-dna hybridization data obtained in this study show that the a. bestiarum-like strains constitute a separa ...19979336924
aeromonas spp. possess at least two distinct type iv pilus families.type iv pili have been purified from strains of most of the aeromonas species associated with gastroenteritis (a. veronii biovar sobria, a. hydrophila, a. trota and a. caviae). they appear to be a related family (molecular mass of pilin 19 to 23 kda) with a tendency to bundle-formation. hence, we have designated them 'bundle-forming pili' (bfp). a type iv pilus biogenesis gene cluster (tapabcd) recently cloned from a strain of a. hydrophila, however, encoded a 17 kda pilin which differed signifi ...19979344785
enteropathogenic bacteria in the la paz river of bolivia.diarrheal diseases often result from ingestion of contaminated water or food. the population of la paz, bolivia is directly or indirectly exposed to the sewage-contaminated la paz river. we conducted a bacteriologic survey of the la paz river to quantify the level of bacterial contamination, with particular reference to enteropathogens. a total bacterial count exceeding 10(6) colony-forming units (cfu)/ml, including lactose fermenting and nonfermenting, gram-negative bacilli of approximately 10( ...19979347960
toxicity of crude extracellular products of aeromonas hydrophila in tilapia, tilapia nilotica.extracellular products (ecp) secreted from aeromonas hydrophila with haemolytic and proteolytic activity were studied with respect to temperature and time of incubation as well as the lethal toxicity on tilapia, tilapia nilotica. the highest production of the haemolysin product was achieved when aer. hydrophila was grown at 35 degrees c for 30 h. tilapia erythrocyte was found to be more susceptible than sheep erythrocyte for determining the haemolytic activity. the haemolytic activity against ti ...19979351277
sequence and expression of an eisenia-fetida-derived cdna clone that encodes the 40-kda fetidin antibacterial protein.fetidins are 40-kda and 45-kda hemolytic and antibacterial glycoproteins present in the coelomic fluid of the earthworm eisenia fetida andrei. by screening a cdna library with a polyclonal antifetidin serum, we have cloned a cdna that encoded the 40-kda fetidin. the clone contains an insert of 1.44 kb encoding a protein of 34 kda, which corresponds to the size of deglycosylated fetidins. the recombinant protein inhibits bacillus megaterium growth. restriction fragment polymorphisms were observed ...19979219536
[bacteremia for aeromonas sobria in a patient with cholecystitis]. 19979221025
molecular and phenotypic methods for the characterization of atypical aeromonas salmonicida.atypical aeromonas salmonicida form a taxonomically diverse group among the psychrophilic a. salmonicida. characteristics of 53 atypical a. salmonicida strains originating from finland, denmark, norway and sweden were studied using 60 phenotypic tests. ribopattern analysis and plasmid profiles were used as genetic methods. the production of brown pigment on the furunculosis agar containing l-tyrosine divided the atypical oxidase-positive strains into two groups: pigment-producing (n = 35) and ac ...19979228690
the role of flagella and motility in the adherence and invasion to fish cell lines by aeromonas hydrophila serogroup o:34 strains.we compared the ability of aeromonas hydrophila wild-type strains of serogroup o:34, non-motile tn5 aflagellar mutants and the same mutants harboring a recombinant cosmid dna from a library of a. hydrophila ah-3 (o:34, wild-type) that allows these mutants to make flagella and to be motile, to adhere and invade two fish cell lines. we found that motility is essential in these strains for adhesion, and also that possession of flagella is essential for the ability to invade the fish cell lines. we ...19979228756
purification and characterization of l-allo-threonine aldolase from aeromonas jandaei dk-39.l-allo-threonine aldolase (l-allo-threonine acetaldehyde-lyase), which exhibited specificity for l-allo-threonine but not for l-threonine, was purified from a cell-free extract of aeromonas jandaei dk-39. the purified enzyme catalyzed the aldol cleavage reaction of l-allo-threonine (k(m) = 1.45 mm, vmax = 45.2 mumol min-1 mg-1). the activity of the enzyme was inhibited by carbonyl reagents, which suggests that pyridoxal-5'-phosphate participates in the enzymatic reaction. the enzyme does not act ...19979228760
secreted enzymes of aeromonas.a hallmark characteristic of species of aeromonas is their ability to secrete a wide variety of enzymes associated with pathogenicity and environmental adaptability. among the most intensively studied are beta-lactamases, lipases, hemolytic enterotoxins, proteases, chitinases, nucleases and amylases. multiple copies of genes encoding each type of enzyme provide additional biological diversity. except for the chitinases, these multiple copies show little evolutionary relatedness at the dna level ...19979228763
computer aided assignment of motile aeromonas strains to genospecies level by standard biochemical tests.a procedure is given for differentiation of motile aeromonas spp. based on nine to 12 biochemical properties it allows an assignment of isolated aeromonas strains first to phenotypes and, in the second step, to hybridization groups (hgs) 1-13 as well as to the genotypically defined species aer. allosaccharophila and aer. encheleia. the computer aided classification is carried out according to the principles of numerical taxonomy. using this differentiation scheme 23 aeromonas strains, which were ...19979230673
molecular and phenotypic features of aeromonads isolated from snails (helix aspersa) affected with a new summer disease.forty-four aeromonads were isolated during the summer of 1994 from snails (helix aspersa) affected or not by a newly described disease. snta 1 rrna gene restriction patterns (ribotyping) and nine selected conventional phenotypic tests were performed to retrospectively determine relationships among these isolates regarding the disease. results from ribotyping were found highly discriminant in strain differentiation and suggest the possible existence of a group of aeromonas associated with the dis ...19979230675
structurally defined epitopes of haemophilus ducreyi lipooligosaccharides recognized by monoclonal use of enzyme-linked immunosorbent assay and immunoblotting techniques, the migration patterns and binding epitopes of lipooligosaccharides (los) from 10 haemophilus ducreyi strains were investigated with two monoclonal antibodies (mabs), mahd6 and mahd7, raised against los from h. ducreyi itm 2665. closely related los, with defined structures, from haemophilus influenzae, bordetella pertussis, aeromonas spp., and synthetic glycoproteins were also included in the analyses. the mabs bound to c ...19979234768
continuous spectrophotometric assay of peptide deformylase.a continuous assay for peptide deformylase has been developed using a formylated dipeptide, formyl-met-leu-p-nitroanilide, as substrate. removal of the formyl group by a peptide deformylase renders the dipeptide product, which contains a free nh2 terminus, a substrate for an aminopeptidase from aeromonas proteolytica. sequential hydrolysis of the dipeptide by the aminopeptidase releases a p-nitroaniline, which is monitored spectrophotometrically at 405 nm. this assay was applied to determine the ...19979234895
rapid purification, partial characterization, and antimicrobial spectrum of the bacteriocin, pediocin acm, from pediococcus acidilactici m.the bacteriocin from pediococcus acidilactici m, designated as pediocin acm, was rapidly purified to homogeneity by the ph mediated cell adsorption-desorption method and semi-preparative reversed-phase hplc. the purification yield was 40.4% and the specific activity was increased by 2450-fold. it gave a single band and a single peak on sds-page and hplc analysis, respectively. when subjected to electrospray lc-ms analysis, the protein was found to be highly pure and the molecular weight was dete ...19979237116
evaluation of the synergistic haemolysis (camp-like) test in the identification of motile, mesophilic aeromonas species.usefulness of the synergistic haemolysis (camp-like) test in the identification of aeromonas hydrophila, aeromonas sobria, and aeromonas caviae was evaluated, using beta-toxin producing staphylococcus aureus atcc 25923 and alpha-toxin producing clostridium perfringens atcc 13124 as sphingomyelinase producing indicator strains. the tests were done on columbia blood agar base supplemented with 5% sheep blood (cba; difco laboratories, detroit, mi, usa). when cultured aerobically, 77% of a. hydrophi ...19979241799
pyomyositis of the anterior tibial compartment.five oncology patients developed bacterial pyomyositis involving the anterior tibial compartment and resulting in compartment syndrome with ischemia and abnormalities of neuromuscular function. all patients were neutropenic and thrombocytopenic, and four were receiving or had recently received cancer chemotherapy. three infections were due to gram-negative bacilli and two to staphylococcus aureus. appropriate antimicrobial therapy and surgical drainage in four patients resulted in the resolution ...19979243048
cloning and analysis of the poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) biosynthesis genes of aeromonas caviae.a 5.0-kbp ecorv-ecori restriction fragment was cloned and analyzed from genomic dna of aeromonas caviae, a bacterium producing a copolyester of (r)-3-hydroxybutyrate (3hb) and (r)-3-hydroxyhexanoate (3hhx) [p(3hb-co-3hhx)] from alkanoic acids or oils. the nucleotide sequence of this region showed a 1,782-bp poly (3-hydroxyalkanoate) (pha) synthase gene (phac(ac) [i.e., the phac gene from a. caviae]) together with four open reading frames (orf1, -3, -4, and -5) and one putative promoter region. t ...19979244271
spectroscopically distinct cobalt(ii) sites in heterodimetallic forms of the aminopeptidase from aeromonas proteolytica: characterization of substrate binding.the co(ii)zn(ii)- and zn(ii)co(ii)-substituted derivatives of the aminopeptidase from aeromonas proteolytica (aap) were probed by epr spectroscopy. epr spectra of the high-spin s = 3/2 co(ii) ions in [cozn(aap)] and [znco(aap)] indicated that each metal binding site provides a spectroscopically distinct signature. for [cozn(aap)], subtraction of epr spectra recorded at ph 7.5 and 10 revealed that two species were present and that the relative contributions to each of the experimental spectra wer ...19979245416
mode of primary binding to target membranes and pore formation induced by vibrio cholerae cytolysin (hemolysin).vibrio cholerae cytolysin (vcc) is produced by many non-choleratoxigenic strains of v. cholerae, and possibly represents a relevant pathogenicity determinant of these bacteria. the protein is secreted as a pro-toxin that is proteolytically cleaved to yield the active toxin with a molecular mass of approximately 63 kda. we here describe a simple procedure for preparative isolation of mature vcc from bacterial culture supernatants, and present information on its mode of binding and pore formation ...19979249028
pathogenic analysis of aeromonas hydrophila septicemia.aeromonas hydrophila has emerged as a potential pathogen in the immunocompromised host. various aeromonal infections, including septicemia, have also been reported in apparently healthy individuals. for years, researchers have disagreed over the epidemiologic roles of aeromonads in gastroenteritis. isolation rates of aeromonads by stool culture among patients with gastroenteritis are not consistently high. carriers of this bacterium also exist. the septicemic course is, however, often fulminant ...19979210970
a monoclonal antibody reacts with maltose-binding protein of escherichia coli and related enteric bacteria.maltose-binding protein (mbp) encoded by male is essential for the energy-dependent translocation of maltose through the cytoplasmic membrane of bacteria. its property of specific binding to maltose has been used in constructing fusion proteins for easy affinity purification. a monoclonal antibody named mab sc1d7 was produced against escherichia coli mbp. this mab also bound to mbp-containing recombinant proteins in both western blotting and immunoprecipitation analysis. as a result, this mab ca ...19979212834
enteropathogens associated with diarrhea among military personnel during operation bright star 96, in alexandria, egypt.this study investigated the microbial causes of diarrheal disease among u.s. troops deployed near alexandria, egypt, during october 1995. bacterial causes associated with 19 cases of diarrhea included: enterotoxigenic escherichia coli (etec), 42% (21% heat-stable, 11% heat-labile, and 11% heat-stable/ heat-labile producers); enteropathogenic e. coli (5.3%); and enteroadherent e. coli (42%). four cases of diarrhea were associated with enteroaggregative e. coli based on probe analysis for enteroag ...19979183160
adherence and invasion of aeromonas caviae to monolayer cells. adherence and invasion of aeromonas caviae. 19979192016
purification and characterization of lipase from aeromonas sobria lp004.lipase from aeromonas sobria lp004, isolated from raw milk, was purified and characterized. the lipase was purified 10.29 fold to a homogeneous state by ultrafiltration and column chromatography on phenyl sepharose. the molecular weight of the lipase determined by sds-page was 97 kda. purified a. sobria lp004 lipase exhibited the maximum activity at ph 6.0 and 45 degrees c and was stable under alkaline conditions (ph 6.5-10.0) and at temperatures lower than 40 degrees c. this lipase could be cla ...19979195755
identification of aeromonas clinical isolates by restriction fragment length polymorphism of pcr-amplified 16s rrna genes.identification of aeromonas species, emergent pathogens for humans, has long been controversial due to their phenotypic and genomic heterogeneities. computer analysis of the published 16s rrna gene sequences revealed that restriction fragment length polymorphism of the pcr-amplified 16s rrna gene is a good and rapid way of assessing the identities of all known species of aeromonas. the method was evaluated with the reference strains of all species (or dna homology groups) and 76 clinical isolate ...19979196171
changes in selected aspects of immune function in the leopard frog, rana pipiens, associated with exposure to cold.the effect of exposure to low temperatures (5 degrees c) on lymphocyte proliferation, leukocyte populations, and serum complement levels was examined in the northern leopard frog, rana pipiens. proliferation of t lymphocytes in response to phytohemagglutinin stimulation was significantly decreased in frogs kept for 2, 3, and 5 months at 5 degrees c compared to that of animals kept at 22 degrees c. a significant increase in the average percentage of neutrophils and a decrease in the mean percenta ...19979203367
antibiotic resistance and plasmid profile of aeromonas hydrophila isolates from cultured fish, telapia (telapia mossambica).strains of aeromonas hydrophila isolates from skin lesions of the common freshwater fish, telapia mossambica, were screened for the presence of plasmid dna by agarose gel electrophoresis and tested for susceptibility to 10 antimicrobial agents. of the 21 fish isolates examined, all were resistant to ampicillin and sensitive to gentamycin. most isolates were resistant to streptomycin (57%), tetracycline (48%) and erythromycin (43%). while seven of 21 isolates harboured plasmids, with sizes rangin ...19979203404
cloning and expression of the cdna encoding prolyl oligopeptidase (prolyl endopeptidase) from bovine brain.prolyl oligopeptidase (ec, prolyl endopeptidase) cdna from bovine brain was cloned by pcr, and the amplified fragment was used as a probe to screen the cdna library from bovine brain. the obtained clone contained a 2.7 kb dna fragment with an open reading frame of 2130 nucleotides, and encoded a protein of 710 amino acids with a deduced molecular weight of 80640 da. the deduced amino acid sequence is 95, 94, 51 and 48% homologous to those of human t-cell, porcine brain, aeromonas hydro ...19979353562
cloning and sequence analysis of the gene (epra1) encoding an extracellular protease from aeromonas hydrophila.a gene (epra1) encoding the extracellular protease of aeromonas hydrophila ah1 has been cloned and sequenced. nucleotide sequence analysis of epra1 predicted a single open reading frame (orf) of 1038 bp encoding a 346 amino acid (aa) polypeptide, with a potential 21-aa signal peptide. when the epra1 gene was expressed in minicells, one major band of approx. 37 kda was identified, while protease activity staining experiments identified a caseinolytic band of approx. 29 kda determined by sds-page ...19979358060
expression and characterization of the recombinant gene encoding chitinase from aeromonas caviae.the gene encoding a chitinase from aeromonas caviae was cloned by pcr techniques. its recombinant gene expression was performed using pet20b(+) in escherichia coli bl21 (de3). the recombinant chitinase with the extra 33 and 13 amino acids in its n- and c-termini, respectively, was purified to near homogeneity using his-tag affinity chromatography. the recombinant chitinase was found to be present in both the culture medium and the cytoplasm. a single protein band on the native polyacrylamide gel ...19979358657
development and application of monoclonal antibodies for in situ detection of indigenous bacterial strains in aquatic ecosystems.strain-specific monoclonal antibodies (mabs) were developed for three different bacterial isolates obtained from a freshwater environment (lake plusssee) in the spring of 1990. the three isolates, which were identified by molecular methods, were as follows: cytophaga johnsonae px62, comamonas acidovorans px54, and aeromonas hydrophila pu7718. these strains represented three species that were detected in high abundance during a set of mesocosm experiments in lake plusssee by the direct analysis o ...19979361440
aeromonas sobria-associated left-sided segmental colitis.aeromonas species, once thought pathogenic only in immunocompromised hosts, have more recently been found to be associated with many different infections in previously healthy individuals. the most common site of these infections is the gastrointestinal tract. we describe a 67-yr-old woman who presented with abdominal pain and bloody diarrhea and was diagnosed with left-sided, segmental colitis due to aeromonas sobria, which was proven by stool culture. extensive work-up for ischemic colitis was ...19979362202
incidence and clinical symptoms of aeromonas-associated travellers' diarrhoea in a survey examining the causes of travellers' diarrhoea treated in tokyo between july 1986 and december 1995, aeromonas species were isolated from 1265 (5.5%) of 23,215 travellers returning from developing countries. aeromonas species were the fourth most frequent enteropathogen isolated, following enterotoxigenic e. coli (8.5%), salmonella spp. (7.6%) and plesiomonas shigelloides (5.6%). aeromonas species were found in 1191 (5.6%) of 21,257 patients with diarrhoea and in 74 (3.8%) of 1958 hea ...19979363009
influence of iron, growth temperature and plasmids on siderophore production in aeromonas hydrophila.aeromonas hydrophila strains obtained from diarrhoeal samples of human patients (19 isolates) and freshwater ponds (11 isolates) were analysed for siderophore production. both clinical and environmental isolates showed significantly increased siderophore production under iron-limiting conditions both at 28 degrees c and at 37 degrees c. clinical isolates consistently produced higher levels of siderophores than did the environmental isolates. the role of plasmids in moderating siderophore product ...19979364139
determination of the amino acid sequence of the plant cytolysin enterolobin.the cytolytic seed protein enterolobin from seeds of enterolobium contortisiliquum was purified by using fplc on a mono q column giving a single peak in capillary electrophoresis. the complete amino acid sequence of the plant cytolysin was determined by an automated method, yielding a molecular mass of 54,806 da. databank searches and sequence alignment demonstrated a high degree of sequence identity and similarity between enterolobin and bacterial aerolysins from aeromonas hydrophila and a. sob ...19979367525
general secretion pathway (eps) genes required for toxin secretion and outer membrane biogenesis in vibrio cholerae.the general secretion pathway (gsp) of vibrio cholerae is required for secretion of proteins including chitinase, enterotoxin, and protease through the outer membrane. in this study, we report the cloning and sequencing of a dna fragment from v. cholerae, containing 12 open reading frames, epsc to -n, which are similar to gsp genes of aeromonas, erwinia, klebsiella, pseudomonas, and xanthomonas spp. in addition to the two previously described genes, epse and epsm (m. sandkvist, v. morales, and m ...19979371445
[transient bacteremia caused by aeromonas jandaei]. 19979376410
[ascitic fluid infection and enteritis by aeromonas hydrophila]. 19979379726
[the prevalence of aeromonas spp. in the diarrheal feces of children under the age of 5 years in the city of goiânia, goiás in the 1995-1996 biennium].from 1995 through 1996, 163 fecal specimens of children aged under 5 years were analysed, 91 being from diarrhea feces and 72 without diarrhea. the material was collected in transport medium and submitted to the enrichment procedure at 4 degrees c for 7 days. for the primary isolation starch ampicillin agar was used and incubated at 35 degrees c for 18 to 24 hours. twenty (20.9%) from the following specimens were isolated: aeromonas (a.) caviae (7.7%), a. salmonicida salmonicida (6.6%), a. sobri ...19979380898
bacterial pathogens associated with diarrhoea on the island of crete.stool specimens from 3,600 diarrhoeal patients from the island of crete, greece, were examined for bacterial pathogens, during a three-year period (1992-1994). one or more pathogens were identified in 826 patients (22.9%), more often from children. salmonella spp. were the most frequently isolated organisms in 13.6% of the patients, followed by campylobacter in 4.7%, and enteropathogenic escherichia coli (epec) in 3.9%. yersinia enterocolitica was found in 0.7%, shigella spp. in 0.7% and aeromon ...19979384274
species, biotype and serogroup of campylobacter spp. isolated from children with diarrhoea over a ten-year period.from 1981 to 1990, stool samples from 6403 gastroenteritis cases were examined for the presence of campylobacters as well as salmonella, shigella, aeromonas species and yersinia enterocolitica. the percentages of isolation were the following: campylobacters 10.8 (86.1% of isolates were c. jejuni and 13.9% were c. coli), salmonella spp. 8.4, aeromonas spp 1.4, yersinia enterocolitica 0.3. shigella spp. were isolated only occasionally. predominant biotypes of campylobacters were c. jejuni i (69.5% ...19979385599
aeromonas sobria endophthalmitis.aeromonas sobria causes a rare gram-negative bacterial water-borne infection. it has been found in waters of north queensland and south-east asia. of all aeromonas species, a. sobria is the most virulent and invasive and has been reported to cause soft tissue infection and corneal ulcer.19979395834
inhibition of the metallo-beta-lactamase produced from serratia marcescens by thiol compounds.low molecular weight thiol compounds have been found to be strong inhibitors of metallo-beta-lactamase (imp-1) produced by serratia marcescens tn9106, which was expressed by echerichia coli jm109 cells. mercaptoacetic acid and 2-mercaptopropionic acid strongly and competitively inhibited imp-1 with ki of 0.23 and 0.19 microm, respectively. 2-mercaptoethanol reversibly inhibited imp-1 but did not show simple competitive inhibition.19979401719
antimicrobial activity of 12 broad-spectrum agents tested against 270 nosocomial blood stream infection isolates caused by non-enteric gram-negative bacilli: occurrence of resistance, molecular epidemiology, and screening for metallo-enzymes.a total of 270 recent nosocomial blood stream isolates of non-enterobacteriaceae gram-negative bacilli representing nearly 50 u.s. medical centers were characterized. the numbers of isolates of individual organisms were: pseudomonas aeruginosa (n = 204), acinetobacter spp. (n = 48), and stenotrophomonas maltophilia (n = 18). mics were determined using the broth microdilution susceptibility method with 12 antimicrobial agents: piperacillin, piperacillin/tazobactam, ceftriaxone, ceftazidime, cefep ...19979401811
[meropenem: microbiologic perspective].meropenem is a beta-lactamic carbapenem derived from thienamycin and is structurally characterized by the presence of a beta-methyl group in position c1 which confers stability to the molecule versus renal dehydropeptidase 1 (dhp-1), thereby making the coadministration of an enzyme inhibitor unnecessary. its esterochemical configuration of the lateral chain in c2 (dimethyl carbomoilpyrrolidenethium) increases the activity versus gram negative bacteria (enterobacteria and pseudomonas) and moreove ...19979410064
pathogenicity of atypical aeromonas salmonicida in atlantic salmon compared with protease production.the pathogenicity of extracellular products (ecps) from 24 atypical aeromonas salmonicida strains was studied with respect to: lethality in atlantic salmon, pathogenic effect in muscle, haemolytic activity, cytotoxicity in two fish cell lines and proteolytic activities. furthermore, the relationship between lethality of ecps and mortality caused by bacterial challenge was examined. correlation was demonstrated between the pathogenic properties and proteolytic activities of the ecps. cytolytic (g ...19979418019
antimicrobial activity among pseudomonas and related strains of mineral water origin.siderophore production in 382 pseudomonas and related strains of mineral water origin were screened and the antimicrobial activities of 158 of these tested against nine target organisms of health significance. presence of siderophores could be detected in 54.4% and the majority of strains tested (91.2%) inhibited at least one of the nine target strains. staphylococcus, escherichia coli and aeromonas hydrophila were particularly sensitive. addition of iron eliminated the inhibitory activity in 96 ...19979418027
reappraisal of the effect of temperature on the growth kinetics of aeromonas salmonicida.the effect of temperature (1-34 degrees c) on the maximum specific growth rate of aeromonas salmonicida could not be described by the classical growth models; for some strains, two optimal temperatures at 23 degrees c and 30 degrees c were observed, as well as an unexpected increase in the pseudolag time above 27 degrees c. this could be explained by the presence of two subsets, notably s-layer+ and s-layer- sub-populations. the a- cells had higher growth parameters (topt and mu opt) than the a+ ...19979418073
enzyme-linked immunosorbent assay for detection of aeromonas hydrophila serogroup enzyme-linked immunosorbent assay has been developed for the detection of aeromonas hydrophila serogroup o:19 isolated from epizootics in eels. the enzyme-linked immunosorbent assay specificity was confirmed after testing a. hydrophila o:19 and non-o:19 strains from different origins, as well as other aeromonas species and other fish pathogens such as vibrio vulnificus biotype 2, v. furnisii, v. damsela, yersinia ruckerii and edwardsiella tarda. the detection limits for a. hydrophila o:19 cel ...19979418247
[prevalence of aeromonas spp. in surface water].some aeromonas strains are well recognized enteropathogens according to microbiological, clinical, immunological and epidemiological evidence. the main source of infection seems to be untreated water, these microorganisms can be found in virtually all aquatic environments. additionally, some aeromonas, which include enterotoxigenic strains, are capable of rapid growth at 5 degrees c and even of producing toxins. vegetable products irrigated with contaminated water may reach critical aeromonas le ...19979429640
characterization of the bacterial flora isolated from a pilot-scale lagoon processing swine manure.the bacterial flora of an experimental plant that processes liquid swine manure by an aerated compartmented (multistage) lagoon system has been studied. the total flora is characterized by a larger number of oligotrophic bacteria than eutrophic ones. each compartment displays a specific flora, different from the flora in the manure, and consisting of a complex assembly of gram-negative and gram-positive ubiquitous species, such as aeromonas spp. and pseudomonas spp., and specialized species, suc ...19979436310
detection and speciation of bacteria through pcr using universal major cold-shock protein primer oligomers.the detection of bacteria using pcr is a well-established diagnostic technique. however, conventional pcr requires the use of dna primer oligomers that are specific to the target organism and, as a consequence, a sample can only be tested for the presence of that specific target. a significant advantage would be to probe a sample for the presence of any bacteria, followed by identification. to achieve this it is necessary to identify a dna sequence common to all bacteria. here we demonstrate tha ...19979439003
effect of amino acids on the production and activities of cephalosporin c acylase and penicillin v acylase from aeromonas species acy 95.amino acids altered the production and activities of cephalosporin c acylase and penicillin v acylase from aeromonas species acy 95 to a varying degree. dl-tryptophan enhanced the cephalosporin c acylase formation by 222% while suppressed the penicillin v acylase formation by 68%.19979440283
virulence factors-pathogenicity relationships for aeromonas species from clinical and food isolates.the presence of virulence factors in 96 aeromonas strains isolated from food and clinical samples was studied. neither cytotoxic activity and hydrophobicity, not the presence of pili or an extra surface layer made it possible to establish differences between food and clinical strains. statistical studies showed that cytotoxin production was associated with a positive voges-proskauer reaction, inability to ferment arabinose and a positive lysine decarboxylation. therefore, when comparing cytotoxi ...19979449784
[detection of the thermostable lipase gene (lipah) in clinical isolates of aeromonas hydrophila belonging to the major o serogroups o11, o16 and o34].on the basis of dna hybridization data and phenotypes, most pathogenic strains of aeromonas hydrophila are grouped into hybridization group 1 (hg1). these pathogenic strains secret the theromostable lipase, and it's gene (lipah) has been cloned and sequenced. the present study was performed to identify the pathogenic strains of a. hydrophila by the polymerase chain reaction (pcr) technique to detect the lipah. synthetic oligonucleotide primers (lipah-ns-1 and -na-1) were used in the pcr. the pcr ...19979455059
further characterization of renibacterium salmoninarum extracellular products.renibacterium salmoninarum, the agent of bacterial kidney disease in salmonids, releases high concentrations of extracellular protein in tissues of infected fish. the extracellular protein consists almost entirely of a 57-kda protein and derivatives of degradation and aggregation of the same molecule. the 57-kda protein and its derivatives were fractionated into defined ranges of molecular mass. separated fractions continued to produce degradation and aggregation products. one-dimensional electr ...19979480644
acute rhabdomyolysis and myonecrosis complicating aeromonas bacteremia in neutropenic patients with hematologic malignancies: report of two cases.infections by aeromonas spp. are a rare cause of systemic infection in normal and immunocompromised hosts. we report the cases of two patients with acute non-lymphoblastic leukemia who developed septic shock by aeromonas species with unusual soft-tissue complications. one patient who was undergoing consolidation chemotherapy developed septic shock by aeromonas hydrophila with rhabdomyolysis and subsequent soft-tissue destruction consistent with myonecrosis. she recovered with combination antibio ...19979499669
meat from dairy cows: possible microbiological hazards and risks.the authors provide an overview of the circumstances associated with culling of dairy cattle in the united states of america (usa) and focus on the possible significant microbiological hazards associated with meat from cull dairy cows. cull dairy cows are an important source of food in the usa, accounting for at least approximately 17% of ground beef. the potential microbiological hazards for foodborne illness from cull dairy cows discussed here include salmonella (with special attention to s. t ...19979501354
the role of seafood in foodborne diseases in the united states of the united states of america, seafood ranked third on the list of products which caused foodborne disease between 1983 and 1992. outbreaks connected with fish vectors were caused by scombroid, ciguatoxin, bacteria and unknown agents; in shellfish, unknown agents, paralytic shellfish poisoning, vibrio spp. and other bacteria, followed by hepatitis a virus, were responsible for the outbreaks. at least ten genera of bacterial pathogens have been implicated in seafood-borne diseases. over the pas ...19979501377
effects of temperature, medium composition, ph, salt and dissolved oxygen on haemolysin and cytotoxin production by aeromonas hydrophila isolated from oyster.the effects of temperature, medium composition, ph, salt content and dissolved oxygen (do) on the production of haemolysin and cytotoxin by one strain of aeromonas hydrophila isolated from oyster were investigated. four media were tested: brain heart infusion broth (bhib), casamino acid-yeast extract broth (cayeb), nutrient broth (nb), and trypticase soy broth (tsb). bhib was the best for toxin production even though the growth rates for aeromonas hydrophila in all of these media were quite simi ...19979506276
isolation and identification of aeromonas species from human thousand and three diarrhoeal stool samples were processed in our laboratory during the period 1996/1997 for the presence of enteric pathogens especially aeromonas spp., which has emerged as a new agent causing diarrhoea. ampicillin sheep blood agar was found to be the best medium for the isolation of aeromonas spp. from stool specimens. enteric pathogens were found in 200 (20%) stools, of which aeromonas spp. was the second commonest pathogen isolated amounting to 21% of isolates. this stud ...19979510643
rflp-pcr analysis of the aroa gene as a taxonomic tool for the genus aeromonas.the aroa gene has been identified as a target in screening for the presence of most aeromonas species so far described by pcr. synthetic oligonucleotide primers of 24 and 25 nucleotides were used by pcr assay to amplify a sequence of the aroa gene, which encodes 3-phosphoshikimate-1-carboxyvinyltransferase, a key enzyme of aromatic amino acids and folate biosynthetic pathway. a 1236-bp dna fragment, representing most of the aroa gene, according to the nucleotide sequence of a. salmonicida, was a ...19979513265
[aeromonas infections]. 19979569900
selenite bioremediation potential of indigenous microorganisms from industrial activated sludge.ten bacterial strains were isolated from the activated sludge waste treatment system (biox) at the exxon refinery in benicia, california. half of these isolates could be grown in minimal medium. when tested for selenite detoxification capability, these five isolates (members of the genera bacillus, pseudomonas, enterobacter and aeromonas), were capable of detoxifying selenite with kinetics similar to those of a well characterized bacillus subtilis strain (168 trp+) studied previously. the seleni ...19979608517
occurrence of gram-negative bacteria in drinking water undergoing softening treatment.a study was carried out on the presence of gram-negative bacteria in the municipal waters of bologna (italy) undergoing softening using domestic ion exchangers with an automatic disinfection mechanism. the softening process was seen to cause a 15 fold increase in 22 degrees c and 36 degrees c heterotrophic plate counts. there was a 30 fold increase in gram-negative bacteria and their number correlated directly with temperature and inversely with active residual chlorine. organic matter had no ef ...19979636986
enteric bacterial pathogens in stools of residents of urban and rural regions in nigeria: a comparison of patients with and without diarrhoea and controls without diarrhoea.a total of 2,400 stool samples comprising 1,200 from patients with diarrhoea (600 each from urban and rural area) and 1,200 similarly divided controls were obtained from school children and clinic attendants of government and private clinics around three designated study centres of edo, lagos and cross river states, nigeria. these were screened for the prevalence of bacteria that could cause diarrhoea. diarrhoea cases in urban areas had a high prevalence rate for campylobacter spp. (28%), follow ...19979661320
diversity, persistence, and virulence of aeromonas strains isolated from drinking water distribution systems in sweden.the aeromonas populations in 13 swedish drinking water distribution systems, representing different treatments, were investigated. from each system, water samples were collected four times during the period from may to september 1994 from raw water and water after treatment and at two to five sites within the distribution system. in total, 220 water samples were collected. from samples containing presumptive aeromonas, up to 32 colonies were analyzed by the pheneplate aeromonas (php-ae) system, ...199711799982
the suppressive excretory-secretory product of trichobilharzia ocellata: a possible factor for determining compatibility in parasite-host interactions.factors which may determine trematode-snail interactions were assessed in the present study. compatibility was examined using a bacterial clearance assay to detect the modulatory effects of both compatible and incompatible trematode infections on the activity of haemocytes from lymnaea stagnalis, during the early stages of infection. exposure to and injection with trichobilharzia ocellata, a compatible trematode, or the incompatible schistosoma mansoni, resulted in modulation of haemocyte activi ...199710190175
isolation of vibrio and pseudomonas from brown shrimp (penaeus californiensis holmes) intestine.bacteria of the genera vibrio, pseudomonas and aeromonas were isolated from the intestine of apparently healthy brown shrimp (penaeus californiensis holmes) cultured in a tidal pond. species from these genera of bacteria have been reported as shrimp pathogens and have been involved in human gastrointestinal disorders related to seafood consumption. isolation was done first in marine broth, then in selective media (tcbs, cetrimide and macconkey). the oxidase negative strains were discarded as ins ...199710932719
the role of the capsular polysaccharide of aeromonas hydrophila serogroup o:34 in the adherence to and invasion of fish cell lines.the ability of aeromonas hydrophila serogroup o:34 strains grown under different conditions (capsulated and non-capsulated) to adhere to and invade two fish cell lines was compared. the level of adherence was slightly higher when the strains were grown under conditions promoting capsule formation than when the same strains were grown under conditions which did not promote capsule formation. however, the most significant difference among the wild-type strains grown under conditions promoting caps ...19979765847
Displaying items 2701 - 2800 of 5519