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major shift in prevalence of non-o1 and el tor vibrio cholerae. 19938096978
biogenesis and regulation of the vibrio cholerae toxin-coregulated pilus: analogies to other virulence factor secretory systems.biogenesis of the toxin-coregulated pilus (tcp) of vibrio cholerae 01 is essential for successful bacterial colonization of the small intestine. pilus assembly requires the products of at least seven genes located on the chromosome adjacent to the pilin-encoding gene, tcpa. previously reported tnphoa insertions in the tcp-assembly-deficient v. cholerae strains, kp2.21 and kp4.2, were isolated from the chromosome for further analysis. nucleotide sequencing of the tcpe::phoa and tcpf::phoa fusions ...19938097177
genetic organization and sequence of the promoter-distal region of the tcp gene cluster of vibrio cholerae.the nucleotide sequence of the promoter distal region of the major operon associated with biosynthesis of tcp, the toxin coregulated pilus of vibrio cholerae has been determined. the genes tcpr, tcpd, tcps, tcpt, tcpe and tcpf are organized to permit translational coupling and are followed by an inverted repeat structure which is likely to act as a strong rho-independent terminator. tcps and tcpf possess n-terminal signal sequences and would be expected to be periplasm and outer membrane located ...19938097178
pili of vibrio cholerae widely distributed in serogroup o1 strains.the distribution of vibrio cholerae o1 pili consisting of 16 kda subunit protein (16k-pili) was examined by western blotting, using 211 strains from various origins and specific anti-16k-pili sera. the 16 kda protein was detected in all 211 strains. the pili were purified from 3 el tor and 3 classical strains, and characterized by hemagglutination and inhibition tests. all purified pili were hemagglutinative. however, the hemagglutinating activity of classical pili disappeared after exposure to ...19938097272
antibody cross-reactions with lipopolysaccharide from e. coli o157 after cholera vaccination. 19938098423
outbreak of vibrio cholerae non-o1 in india and bangladesh. 19938098474
detecting and biotyping vibrio cholerae o1 with multiplex polymerase chain reaction. 19938100020
vibrio cholerae non-o1--the eighth pandemic? 19938101894
large epidemic of cholera-like disease in bangladesh caused by vibrio cholerae o139 synonym bengal. cholera working group, international centre for diarrhoeal diseases research, bangladesh.epidemics of cholera caused by vibrio cholerae o1 occur regularly in bangladesh, but until lately v cholerae non-o1 has been associated only with sporadic cases of diarrhoeal disease in many parts of the world, including bangladesh. we describe a large epidemic of cholera-like disease in bangladesh that is due to a v cholerae non-o1. the epidemic began in december, 1992, in southern bangladesh and spread throughout the country. by the end of march 107,297 cases of diarrhoea and 1473 deaths had b ...19938101899
isolation of vibrio cholerae o139 bengal from water in bangladesh. 19938101919
non-o1 vibrio cholerae. 19938101920
vibrio cholerae o139 bengal in bangkok. 19938101921
blood stream invasion by vibrio cholerae o139. 19938101922
bacteremic cellulitis caused by non-o1 vibrio cholerae: report of a case.a 44-year-old man presented with a fever of a two-day duration and bullous cellulitis of the lower extremities. he had prepared and eaten saltwater fish three days prior to admission. both blood and bullous fluid cultures showed non-o1 vibrio cholerae. the bacteremic cellulitis resolved gradually after four weeks of intravenous cefamandole therapy and surgical debridement. non-o1 v. cholerae bacteremia is rarely reported in the english-language literature and is almost always associated with sal ...19938104603
a 20-kda pilus protein with haemagglutination and intestinal adherence properties expressed by a clinical isolate of non-01 vibrio cholerae.a clinical isolate of non-01 v. cholerae (10325) was shown to exhibit higher haemagglutination and intestinal adherence activities in vitro when grown in enriched media, such as trypticase soy broth (tsb) as compared to those of cells grown in a synthetic tris-buffered or 't'-medium. a comparison of their cell-surface protein and lipopolysaccharide profiles suggested the involvement of a 20-kda protein in the cellular adherence process. an antiserum, raised specifically against the 20-kda protei ...19938104843
cholera isolates in relation to the "eighth pandemic". 19938105182
cholera isolates in relation to the "eighth pandemic". 19938105183
cholera isolates in relation to the "eighth pandemic". 19938105184
cooperative studies on diarrheal diseases.enteric infection still causes the highest global morbidity and mortality in children under 5 years old. while there have been impressive developments in the early treatment of diarrhea, adequate diagnostic techniques are not yet available. an international collaboration was conducted with the national institute of cholera and enteric diseases, calcutta on the rapid diagnosis and prevention of diarrheal diseases. forty to fifty per cent of the 780-bed infectious diseases hospital is occupied by ...19938109246
electron microscopic study of phages and aberrant structures produced by induction of prophage kappa in vibrio cholerae el tor cells.prophage kappa in v. cholerae el tor strain slh22(j) could be induced spontaneously or by treatment with nitrofurantoin, though the efficiency of induction was very low (not more than 0.8%). v. cholerae el tor cells were found to release many different aberrant structures of the temperate phage, kappa. these aberrant structures were characterized by density gradient centrifugation and electron microscopy.19938112775
[the ecological and geographical aspects of the spread of vibrio cholerae in environmental objects].the results of studies carried out over the period of 24 years have revealed that v. eltor is widely spread in different ecological systems over a considerable part of the territory of the former ussr in the temperate and subtropical climatic zones. the duration and seasonal character of the isolation of these bacteria depend on climatic and geographical conditions, and their isolation rate greatly depends on the epidemic situation. the intensity and seasonal character of the isolation of v. elt ...19938067067
[the isolation of vibrio cholerae strains that produce cholera toxin and its b-subunit].the creation of two v. cholerae strains, belonging to the classical biovar, serovars ogawa and inaba, and serving as hyperproducers of cholera toxin, is described. the strains have been created by means of recombinant plasmid pco107-2, carrying the cloned gene of cholera toxin vctab. the use of recombinant plasmid piemz3 carrying the cloned gene of the b-subunit of cholera toxin vctb has made it possible to obtain a strain, capable of producing the b-subunit of cholera toxin, on the basis of v. ...19938067088
[the virulence of vibrio cholerae isolated under different epidemiological situations].the virulence of v. cholerae isolated on the territory of russia and other cis countries from environmental objects and from humans in different epidemic situations during the period of 1987-1991 was studied. the analysis of the data obtained in this study revealed that intensive epidemic complications were linked with the realization of the pathogenic properties of strains, characterized by the presence of the ctx gene and the absence of hemolytic activity. as a rule, in single cases or in isol ...19938067092
[the intraspecific differentiation of vibrio cholerae into toxigenic (vct+) and nontoxigenic (vct-) variants by the immunotype of its temperate phages]. 19938067107
[the determination of the optimal inoculation dose of an oral cholera bivalent chemical vaccine in a controlled trial of the vaccination of children and adolescents].the reactogenicity and immunological effectiveness of different doses of cholera vaccine for oral administration (in tablets), containing choleragen toxoid, ogawa and inaba o-antigens and some of vibrio cholerae exoenzymes, have been tested on 143 children aged 2-17 years. in this investigation the optimum immunization doses of the preparation have been established: two tablets containing 100,000 binding units (bu) of the toxoid and 2,500 units of o-antigen for children 11-14 years; four tablets ...19938067145
the role of toxin-coregulated pili in the pathogenesis of vibrio cholerae o1 el tor.studies in the infant mouse cholera model have evaluated the significance of toxin-coregulated pili (tcp) in the pathogenesis of vibrio cholerae strains of el tor biotype. four el tor strains--two which produce tcp during in vitro growth and two which do not--were mutated by the insertion of an antibiotic-resistance cartridge into the tcpa gene (encoding the pilin monomer). the resulting mutants were otherwise indistinguishable from wild-type and in particular were unaltered in their sensitivity ...19937911968
unusual multiresistant vibrio cholerae o1 el tor in argentina. 19937901493
emergence of multiple drug resistance in vibrio cholerae o1 el tor from ecuador. 19937901494
tandem repeats of cholera toxin gene in vibrio cholerae o139. 19937901495
marine ecosystems. 19937901535
vibrio cholerae o139 in karachi, pakistan. 19937901702
cloning and characterization of three hemolysin genes from aeromonas salmonicida.two hemolysin genes (ash3 and ash4) of aeromonas salmonicida strain 17-2 and one (ash1) of a. salmonicida atcc14174 were cloned into the cosmid vector charomid 9-36 in escherichia coli dh1. the overall amino acid sequence of the ash3 was similar to that of the aerolysins of aeromonas hydrophila and aeromonas sobria, and hemolysins ahh3, ahh4, and ahh5 of a. hydrophila, and hemolysin asa1 of a. sobria. the sequence of ash4 was similar to that of the ahh1 hemolysin of a. hydrophila. the ash4 hemol ...19938309354
new phage typing scheme for vibrio cholerae o1 biotype el tor strains.the conventional phage typing scheme proposed by s. basu and s. mukerjee (experientia 24:299-300, 1968) has been used routinely for identification of the strains at the vibrio phage reference laboratory since 1968. however, because of limitations of this scheme, a new phage typing scheme using five newly isolated phages was incorporated into the conventional scheme. a different definition of routine test dilution (almost confluent lysis) was found to be more useful than the one previously used ( ...19938315000
selective detection of terminally alpha 2-3 and alpha 2-6 sialylated neolacto-series gangliosides by immunostaining on thin layer chromatograms.a method for selective detection of terminally alpha 2-3 and alpha 2-6 sialylated neolacto-series gangliosides has been developed. the procedure involves separation of gangliosides on high performance thin layer chromatography plates, fixation of the silica gel, treatment with vibrio cholerae neuraminidase and incubation of the plates with nlcose4cer-specific antibodies. alkaline phosphatase-conjugated second antibodies were used to visualize bound first antibodies by generating a blue dye from ...19938318834
simultaneous isolation of intestinal iga and igg from rabbits infected intraduodenally with vibrio cholerae 01 by combined lectin affinity chromatography involving jacalin and protein a.immunoglobulins of iga and igg isotypes are formed in host intestines after enteric infections with bacteria such as vibrio cholerae. a method has been developed for the separation of intestinal immunoglobulins from rabbits immunized intraduodenally with live v. cholerae cells by sequential affinity chromatography on immobilized jacalin and immobilized protein a. the jacalin-sepharose 4b bound iga was desorbed with 0.5 m galactose. the protein a-sepharose 4b bound igg was desorbed with 0.1 m cit ...19938319437
from the centers for disease control and prevention. imported cholera associated with a newly described toxigenic vibrio cholerae o139 strain--california, 1993. 19938320772
purification and sequence determination of heat-stable enterotoxin elaborated by a cholera toxin-producing strain of vibrio cholerae o1.four molecular species of heat-stable enterotoxins elaborated by a cholera toxin-producing strain of vibrio cholerae o1 were isolated from its culture supernatant. the amino acid sequence of one of the enterotoxins was determined to be phe-ile-lys-gln-val-asp-glu-asn-gly-asn-leu-ile-asp-cys-cys-glu-ile-cys- cys-asn-pro-ala-cys-phe-gly-cys-leu-asn with three intramolecular disulfide linkages. the other enterotoxins had shorter amino acid sequences in the n-terminal regions, but possessed the same ...19938325391
plants used in guatemala for the treatment of gastrointestinal disorders. iv. vibriocidal activity of five american plants used to treat infections. 19938331964
characterization of the nucm gene coding for a nuclease of the phytopathogenic bacteria erwinia chrysanthemi.the gene nucm encoding a nuclease was cloned from a genomic library of erwinia chrysanthemi. the nucm gene was subcloned, and mutagenized by insertion of a uida-kanr cartridge. this mutation was introduced by recombination into the erwinia chrysanthemi chromosome. the nucm mutant lost nucm activity when tested on a dna plate after 24 hours, but still possessed secondary weak nuclease activity. the nucleotide sequence of nucm was determined. it presents a 798 bp open reading frame, coding for a 2 ...19938332061
structures of two polyamine-containing catecholate siderophores from vibrio fluvialis.from low-iron cultures of vibrio fluvialis aq 0012, two new compounds with siderophore activity were purified by xad-7 adsorption followed by preparative tlc. norspermidine and 2,3-dihydroxybenzoic acid were identified as constituents common to both compounds by gc-ms analyses of their acid hydrolytic products. in addition, l-threonine was identified in the hydrolysate of one compound, named fluvibactin. based on high magnetic nmr analyses, the structure of fluvibactin was established as n4-[2-( ...19938340347
cholera--still a major health problem. 19938341166
tetracycline-resistant vibrio cholerae el tor. 19938341181
human immune response to the 18-kda outer-membrane antigen of vibrio cholerae.the serum igg response of human volunteers challenged with vibrio cholerae o1 was analysed for reactivity to v. cholerae o1 outer-membrane antigens by enzyme-linked immunosorbent assay (elisa) and the immunoblot technique. purified outer-membrane antigen preparations from vibrios grown in low-iron conditions were separated by sds-page. specific immunoblot reactions of human sera showed that an 18-kda antigen, cholera protective antigen, was the major antigen with which sera reacted. elisa reveal ...19938345508
common diarrhea pathogens and the risk of dehydration in young children with acute watery diarrhea: a case-control study.the role of common diarrheal pathogens in dehydration was examined in children with acute watery diarrhea who attended the treatment center of the international centre for diarrhoeal disease research, bangladesh, in dhaka. two hundred sixty-nine children with moderate or severe dehydration were matched with 700 children with no dehydration. vibrio cholerae o1 infections were 5.5 times more likely to be associated with dehydration than in cases without this agent. no significant association could ...19938352397
inhibition of sialidases from viral, bacterial and mammalian sources by analogues of 2-deoxy-2,3-didehydro-n-acetylneuraminic acid modified at the c-4 position.the inhibition of sialidase activity from influenza viruses a and b, parainfluenza 2 virus, vibrio cholerae, arthrobacter ureafaciens, clostridium perfringens, and sheep liver by a range of 2-deoxy-2,3-didehydro-n-acetylneuraminic acid analogues modified at the c-4 position has been studied. all substitutions tested resulted in a decrease in the degree of inhibition of the bacterial and mammalian sialidases. for sialidases from influenza viruses a and b, on the other hand, most of the substituti ...19938358225
host range and transfer efficiency of incompatibility group hi plasmids.hi plasmids are distinguished by their thermosensitive mode of conjugation (transfer efficiency is optimal at 22-30 degrees c) and their capacity to encode multiple antibiotic resistance. these traits have implicated hi plasmids as potential vectors in the dissemination of antibiotic resistance among pathogenic and indigenous bacterial species in water and soil environments. we compared the transfer efficiency of hi plasmids with that of plasmids from 13 other incompatibility groups at 37, 24, a ...19938358670
analysis of enterotoxin synthesis in a vibrio cholerae strain lacking dsba, a periplasmic enzyme involved in disulphide bond formation. 19938359462
construction of genetically marked vibrio cholerae o1 vaccine strains.attenuated vibrio cholerae o1 vaccine strains lacking the gene encoding the a subunit of cholera toxin have proven efficacious in preventing experimental cholera. as these strains move from closed, contained testing environments to large-scale field trials, a readily assayable phenotypic trait to distinguish a vaccine strain from wild-type v. cholerae o1 is desirable. we have constructed three derivatives of the attenuated v. cholerae strain cvd 103 which carry a mercury resistance or urease mar ...19938359676
prevalence of a vibrio cholerae 18-kda antigen in vibrios.an 18-kda protein that occurs in vibrio cholerae has been described as an in vivo and low-iron regulated outer membrane antigen. monoclonal antibodies which recognized this antigen were protective as passive vaccines in the infant rabbit model of cholera disease. in this study, those monoclonal antibodies were used in three immunological assays for surveillance of various bacteria for the 18-kda antigen. elisa, and western blot assays gave variable results with bacteria or outer membrane prepara ...19938359680
safety, immunogenicity, and excretion pattern of single-dose live oral cholera vaccine cvd 103-hgr in peruvian adults of high and low socioeconomic levels.groups of 122 peruvian adults of low socioeconomic level (sel) and 125 of high sel received a randomly allocated 5 x 10(9)- or 5 x 10(8)-cfu dose of cvd 103-hgr live oral cholera vaccine or a placebo. the vaccine was well tolerated. vibriocidal seroconversions occurred in 78% of high-sel and 72% of low-sel subjects who ingested the high dose and in 78 and 49%, respectively, of those who received the low dose.19938359923
pasteur oral cholera vaccine: studies of reactogenicity, clinical acceptability and immunogenicity in human volunteers.pasteur cholera vaccine consists of isolated antigenic fractions from v. cholerae el tor ogawa and inaba. enteric coated microgranules were prepared from antigen lyophilisate. three doses of this vaccine were administered orally to 19 healthy young thai adults at one week intervals. none of the volunteers experienced untowards reactions. the vibriocidal antibody responses manifested a significant antibody rise (> or = 4 fold) to serovar inaba in 8 vaccinees (42.1%) and ogawa in 4 (21.1%). five a ...19938362286
effect of vibrio cholerae toxin on oral immunization of chickens.cholera toxin from vibrio cholerae has been shown to increase the secretory immune response when given orally with some antigens in mice and rabbits. the present study was designed to determine if cholera toxin was also an effective mucosal adjuvant in chickens. tetanus toxoid was chosen as a model antigen, and response was measured by enzyme-linked immunosorbent assays of intestinal excreta, bile samples, and serum samples. chickens given 20 micrograms of tetanus toxoid had a significant suppre ...19938363507
use of vaginal tampons in sewer surveys for non-o1. vibrio cholerae.vaginal tampons were shown to be a practical alternative to conventional moore swabs for isolating vibrio cholerae from sewage. associated laboratory investigations demonstrated improved isolation of v. cholerae by using 12- or 18-h enrichments in alkaline peptone water, in comparison with 6-h enrichments, when cultures were incubated at ambient temperatures.19938368858
nationwide prevalence of the new epidemic strain of vibrio cholerae o139 bengal in india. 19938370938
clinical profile of acute diarrhoea cases infected with the new epidemic strain of vibrio cholerae o139: designation of the disease as cholera.a total of 113 patients suffering from acute watery diarrhoea caused by the novel epidemic strain of vibrio cholerae non-o1, currently assigned to a new serogroup o139, were investigated in order to determine the clinical presentation of the new epidemic strain causing outbreaks of cholera-like infection in the indian subcontinent. estimations of electrolyte concentration in serum and stool were also performed in a representative number of the above cases. the clinical features and blood and sto ...19938370939
[species specific dna probes for identifying vibrio cholerae].a 1.74 kb hindiii fragment from a vibrio cholerae eltor library of genes was found to be strictly specific for vibrio cholerae strains independent of the biotypes, serotypes and 01-agglutination ability. the fragment was cloned in puc19 vector plasmid. the resultant recombinant plasmid pes78vcs was transformed into escherichia coli strain hb101 resulting in construction of strain km57. the sites for hincii and xhoi were plotted on a restriction map of the cloned fragment. two hindiii-xhoi as wel ...19938371726
[the regional characteristics of the distribution of vibrio cholerae and the methods for its decontamination]. 19938379144
a kinetic-isotope-effect study of catalysis by vibrio cholerae neuraminidase.michaelis-menten parameters for hydrolysis of seven aryl n-acetyl alpha-d-neuraminides by vibrio cholerae neuraminidase at ph 5.0 correlate well with the leaving-group pka (delta pk 3.0; beta 1g (v/k) = -0.73, r = -0.93; beta 1g (v) = -0.25; r = -0.95). the beta-deuterium kinetic-isotope effect, beta d2(v), for the p-nitrophenyl glycoside is the same at the optimum ph of 5.0 (1.059 +/- 0.010) as at ph 8.0 (1.053 +/- 0.010), suggesting that isotope effects are fully expressed with this substrate ...19938379920
cloning and characterization of the vibrio cholerae genes encoding the utilization of iron from haemin and haemoglobin.vibrio cholerae can utilize haemin or haemoglobin as its sole source of iron. four haem utilization mutants of a classical strain of v. cholerae were isolated. these mutations were complemented with phut1, a cosmid clone isolated from a library of wild-type ca401 dna. two independent tn5 insertions into the cloned sequence disrupted function in all of the complemented mutants. escherichia coli 1017 transformed with phut1 failed to utilize haemin as an iron source; a second plasmid containing a d ...19938384684
accessory cholera enterotoxin (ace), the third toxin of a vibrio cholerae virulence cassette.vibrio cholerae causes the potentially lethal disease cholera through the elaboration of the intestinal secretogen cholera toxin. a second toxin of v. cholerae, zot, decreases intestinal tissue resistance by modifying intercellular tight junctions. in this report, a third toxin of v. cholerae, ace (accessory cholera enterotoxin), is described. ace increases short-circuit current in ussing chambers and causes fluid secretion in ligated rabbit ileal loops. the predicted protein sequence of ace sho ...19938389476
vibrio cholerae hlyb is a member of the chemotaxis receptor gene family. 19938401237
very efficient extracellular production of cholera toxin b subunit using bacillus brevis.we have constructed a very efficient synthesis and secretion system for cholera toxin b subunit (ctb) of vibrio cholerae 569b using bacillus-brevis. the constructed expression-secretion vector has the multiple promoters and the signal peptide coding region of the mwp gene, a structural gene for one of the major cell wall proteins of b. brevis strain 47, directly followed by the gene encoding the mature ctb. a large amount of mature ctb (1.4 g per liter of culture) was secreted into the medium. i ...19938405930
genes required for extracellular secretion of enterotoxin are clustered in vibrio cholerae.pleiotropic transposon insertion mutants of vibrio cholerae that are unable to secrete enterotoxin, ha/protease and chitinase through the outer membrane have been isolated. the gene, epsm, responsible for complementation of two of the tn5 insertion mutations was sequenced. it encodes a putative cytoplasmic membrane protein of 18.5 kda that exhibits similarity to proteins required for extracellular secretion of pullulanase, pectate lyase or elastase in other gram-bacteria. it is present on a 15-k ...19938406031
an outbreak of acute diarrhoeal disease amongst tribal population in tripura.a massive outbreak of acute diarrhoeal diseases occurred during march-april, 1992 in the north district of tripura. investigation of the outbreak revealed vibrio cholerae 01 biotype elt or as the main etiologic agent in 50 per cent of patients. the outbreak which started amongst the tribal population might have spread due to prevailing illiteracy, poverty, low personal and domestic hygiene and vulnerable water sources (chhara water).19938406643
cvd110, an attenuated vibrio cholerae o1 el tor live oral vaccine strain.the recent expansion of the seventh cholera pandemic into south america emphasizes the need for a safe, long-lasting, protective, and nonreactogenic vaccine for this disease. since the predominant vibrio cholerae o1 strains in the world today are of the el tor biotype, a bivalent vaccine containing both classical and el tor biotypes may be desirable. we have constructed a new oral vaccine candidate, v. cholerae cvd110 el tor, ogawa, from which all toxin genes so far identified in v. cholerae hav ...19938406837
fatal septicemia and bullae caused by non-01 vibrio cholerae.bullous lesions associated with non-01 vibrio cholerae developed in a patient with hepatic cirrhosis who had recently ingested raw oysters. he died of overwhelming sepsis despite 5 days of aggressive antibiotic therapy. non-01 v. cholerae was isolated from blood, peritoneal fluid, and bullae. the organism produced a cytotoxic factor that destroyed chinese hamster ovary cells. although septicemia caused by non-01 v. cholerae is uncommon, cutaneous manifestations of this organism are even rarer. o ...19938408840
vibrio spp. isolated from natural waters of the city of yangon, myanmar.virulence properties of the environmental isolate of vibrios from natural waters of yangon, myanmar were studied. vibrio spp. were isolated for identification by the membrane filtration method and cultured on thio-sulphate-bile-sucrose media. no vibrio cholerae o1 were isolated. v. cholerae non-o1 were the major vibrio species isolated from the samples. none of them were detected for cholera-toxin-like toxin, thermostable direct haemolysin, or heat-stable enterotoxin. sixty-one isolates gave hae ...19938409281
new strains of vibrio cholerae o139 in india and bangladesh: lessons from the recent epidemics. 19938409283
lessons from recent outbreaks of vibrio cholerae non-01 diarrhoea in the indian subcontinent. 19938409494
virulence patterns of vibrio cholerae non-o1 strains isolated from hospitalised patients with acute diarrhoea in calcutta, india.a collection of 28 strains of vibrio cholerae non-o1 isolated during a 3-year period (1989-1991) from hospitalised patients with acute diarrhoea in calcutta, india, were examined with regard to virulence-associated factors. of the 28 isolates (each representing a case), 18 were isolated as the sole infecting agent; the remaining 10 were recovered as co-cultures from cases infected with v. cholerae o1. of the strains isolated in this study, 82% could be serotyped, with serovars o5 (32.1%), o11 an ...19938411093
identification of toxigenic vibrio cholerae from the argentine outbreak by pcr for ctx a1 and ctx a2-b.a polymerase chain reaction (pcr) to detect a region of the a1 cholera toxin gene was applied to the identification of 43 vibrio cholerae strains isolated from the recent outbreak in argentina. a good correlation was observed between the gm1-enzyme-linked immunosorbent assay (gm1-elisa) to detect the b subunit of the enterotoxin and pcr. however, a v. cholerae non-01 strain that was negative by the elisa test, was positive by the pcr assay for the a1 region. a second pcr test to detect the a2-b ...19938416815
occurrence of 2-o-methyl-n-(3-deoxy-l-glycero-tetronyl)-d-perosamine (4-amino-4,6-dideoxy-d-manno-pyranose) in lipopolysaccharide from ogawa but not from inaba o forms of o1 vibrio cholerae.a structural study by gc-ms, methylation analysis, and 1h and 13c nmr was carried out on alpha (1-->2)-linked linear n-(3-deoxy-l-glycero-tetronyl)-d-perosamine homopolymer constituting the o-polysaccharide chain of lipopolysaccharide from o1 vibrio cholerae ogawa and inaba o forms. occurrence of 2-o-methyl-n-(3-deoxy-l-glycero-tetronyl)-d-perosamine was demonstrated at the non-reducing terminus of the perosamine-homopolymer of lipopolysaccharide from the ogawa o form in contrast to the presence ...19938422256
effects of temperature on adp-ribosylation factor stimulation of cholera toxin activity.the effects of cholera toxin, a secretory product of vibrio cholerae, result from adp-ribosylation of the stimulatory guanine nucleotide-binding (gs) protein of the adenylyl cyclase system. cholera toxin a subunit (cta) also uses agmatine, a simple guanidino compound, several proteins unrelated to gs, and cta itself as alternative adp-ribose acceptors. the effects of toxin occur in the jejunum presumably at body core temperature. with agmatine as a model substrate, the optimal temperature for ct ...19938422366
a protein required for secretion of cholera toxin through the outer membrane of vibrio cholerae.a gene essential for the secretion of cholera toxin from the periplasm of vibrio cholerae into the extracellular medium has been isolated and its nucleotide sequence determined. it encodes a cytoplasmic protein of 56 kda that exhibits a high degree of similarity to gene products required for extracellular protein secretion in several other gram- organisms. sequence similarities in its potential atp-binding site suggest that the protein may act as an energy provider or signal transducer in the pr ...19938423007
secondary vibrio cholerae-specific cellular antibody responses following wild-type homologous challenge in people vaccinated with cvd 103-hgr live oral cholera vaccine: changes with time and lack of correlation with protection.peripheral blood immunoglobulin a antibody-secreting-cell (asc) responses are thought to reflect the mucosal immune response to locally presented antigens. we evaluated the asc response to cholera toxin (ct) and inaba lipopolysaccharide (lps) in 26 north american volunteers following immunization with a single oral dose of live attenuated vibrio cholerae o1 vaccine strain cvd 103-hgr and again upon homologous wild-type challenge with v. cholerae classical inaba 569b. challenge occurred at either ...19938423098
induction of sos like responses by nitrofurantoin in vibrio cholerae el tor cells.treatment of vibrio cholerae el tor strain slh22(j) with nitrofurantoin induced dose-dependent prophage 'kappa', the maximum induction being 6-fold the spontaneous induction level. uv-inactivated 'kappa' phages were weigle reactivated, the maximum weigle factor being 1.8 and 2.0 respectively in nitrofurantoin and uv pretreated el tor strain h218 smr. nitrofurantoin treatment also caused significant filamentation of the el tor strain h218 smr and mutation of these cells from ampicillin sensitivit ...19938427549
phylogenetic relationships of marine bacteria, mainly members of the family vibrionaceae, determined on the basis of 16s rrna sequences.the phylogenetic relationships of 50 reference strains, mostly marine bacteria which require na+ for growth, were determined on the basis of 600 16s rrna nucleotides by using reverse transcriptase sequencing. strains belonging to 10 genera were included (four genera of the family vibrionaceae, the genus aeromonas of the family aeromonadaceae, and the genera alteromonas, marinomonas, shewanella, pseudomonas, and deleya). the sequences were aligned, the similarity values and evolutionary distance ...19938427811
isolation of vibrio cholerae o1 from oysters--mobile bay, 1991-1992.on july 2, 1991, during routine monitoring, the food and drug administration (fda) isolated toxigenic vibrio cholerae o1, serotype inaba, biotype ei tor from oysters and intestinal contents of an oyster-eating fish taken from closed oyster beds in mobile bay. this isolate was indistinguishable from the latin american epidemic strain and differed from the strain of v. cholerae o1 that is endemic to the gulf coast. this report summarizes the public health response to this isolation of v. cholerae ...19938429813
comparison of shiga-like toxin i b-subunit expression and localization in escherichia coli and vibrio cholerae by using trc or iron-regulated promoter systems.shiga-like toxin i (slt-i) b-subunit expression was examined by using the trc promoter in two different constructs, psbc32 and psbc54, in which 710 bp of dna downstream of the b subunit in psbc32 was deleted. the trc promoter in psbc54 was replaced also with the slt-i iron-regulated promoter to create a third plasmid, psbc61. slt-i b-subunit expression was examined from all three plasmids following transfer into escherichia coli jm105 and the cholera toxin a-subunit gene deletion mutant vibrio c ...19938432592
rapid polymerase chain reaction method for detection of vibrio cholerae in foods.the polymerase chain reaction was used to selectively amplify sequences within the cholera toxin operon from vibrio cholerae o1. oysters, crabmeat, shrimp, and lettuce were seeded with v. cholerae and then homogenized or washed with alkaline peptone water, followed by short-term (6- to 8-h) enrichment. a detection limit of as few as 1 v. cholerae cfu per 10 g of food was obtained with amplification reactions from crude bacterial lysates. the method is extremely rapid and obviates the need for dn ...19938434922
circulating cellular immune response to oral immunization of humans with cholera toxin b-subunit.peripheral blood mononuclear cells were taken from subjects before and after oral immunization with cholera toxin b-subunit. cells obtained from naive volunteers before immunization did not proliferate in vitro to b-subunit. oral immunization induced a proliferative response in all volunteers with a peak stimulation index of 20, and was detected up to 1 year later. the proliferative response kinetics suggest the appearance in the blood of primed t cells from the gut coinciding with the disappear ...19938438610
live oral vaccines against cholera: an update.one hundred years elapsed between the first (live, parenteral) cholera vaccine that entered clinical trials in 1885 and the field trials of two oral inactivated cholera vaccines undertaken in bangladesh in the mid-1980s. the oral inactivated vaccines advanced the art by establishing, convincingly, that oral vaccines could protect (although multiple doses were required) and that (at least in adults) protection could last 3 years. attenuated vibrio cholerae o1 strain cvd 103-hgr (deleted of the ch ...19938438619
location of fructose in lipopolysaccharide isolated from 01 vibrio cholerae nih 41r.fructose, a rarely occurring sugar constituent of gram-negative bacterial lipopolysaccharides (lps), is distributed ubiquitously in lps of 01 vibrio cholerae so far examined, but its location in lps has not hitherto been elucidated. it was found that hydrazinolysis of lps successfully affords a derivative retaining virtually all the fructose of intact lps, but no ester-bound phosphate. structural analysis carried out on the lps derivative prepared by the hydrazinolysis of r-type lps isolated fro ...19938440469
cloning and active site mutagenesis of vibrio cholerae dsba, a periplasmic enzyme that catalyzes disulfide bond formation.recently, a gene (dsba) involved in the biogenesis of secreted oligomeric enterotoxins in vibrio cholerae was described, which encodes an exported protein possessing a -cys-pro-his-cys- motif similar to that found in the active sites of eukaryotic and prokaryotic thiol-disulfide oxidoreductases (yu, j., webb, h., and hirst, t. r (1992) mol. microbiol. 6, 1949-1958). here, we report the cloning of the dsba gene of v. cholerae and the demonstration that the encoded periphlasmic enzyme has disulfid ...19938440717
identification of the flagellar antigens of vibrio cholerae el tor and their role in protection.antiserum to the surface antigens of the wild-type flagellate strain kb207 of vibrio cholerae el tor was absorbed with isogenic aflagellate mutant cd12. antibodies remaining in the absorbed serum exhibited specificity to kb207 but not to cd12 and inhibited motility of kb207. proteins from cell-free lysates of kb207 and cd12 were analysed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. cd12 differed from kb207 in the absence of two proteins of 40 and 38 kda. these proteins were dete ...19938447164
identification of a 33 kda antigen associated with an adhesive and colonizing strain of vibrio cholerae el tor and its role in protection.proteins from the cell-free lysates of the wild-type strain kb207 of vibrio cholerae el tor and the isogenic non-adhesive mutant cd11 were analysed by native and denaturing polyacrylamide gel electrophoresis. a protein of 33 kda present in kb207 was absent from cd11. antiserum to the surface antigens of kb207 was absorbed with cd11. antibodies remaining in the serum after absorption reacted to kb207 but not to cd11 as judged by slide agglutination, double gel diffusion and dot blot elisa. antibo ...19938447165
induction and assessment of immunity at enteromucosal surfaces in humans: implications for vaccine development.it is now almost axiomatic that vaccines against enteric infections must be able to stimulate the gut lymphoid tissue to be efficacious and that this goal is usually better achieved by administering immunogens orally rather than parenterally. on the basis of the notion of a common mucosal immunologic system that provides immune reactivity not only at the site of antigen deposition but also at remote mucosal sites, there is much interest in developing oral vaccines against infections in the respi ...19938452962
distribution of the zot (zonula occludens toxin) gene among strains of vibrio cholerae 01 and non-01.the distribution of the zot gene that encodes the zonula occludens toxin, a newly described toxin of vibrio cholerae, among clinical, environmental and food isolates of v. cholerae 01 and non-01 was investigated. both the zot gene and the ctx gene that encode cholera toxin were found in 247 of 257 clinical strains and 62 of 415 environmental or food isolates of v. cholerae 01. the zot gene, but not the ctx gene was found in 37 strains (one clinical strain and 36 environmental or food isolates). ...19938454179
heterogeneity in the molecular species of heat-stable enterotoxin of vibrio cholerae non-o1 expressed by escherichia coli carrying the cloned toxin gene.the biological activity of the heat-stable enterotoxin of vibrio cholerae non-o1 (nag-st) was found to be predominantly associated with the periplasmic extract (about four-fold higher than the culture supernatant) of a recombinant e. coli (jm109) strain carrying the nag-st toxin gene. four molecular species of nag-st, two each from the periplasmic extract and culture supernatant of jm109, were purified. amino acid sequence analysis of the four nag-st peptides isolated by hplc revealed that they ...19938454187
non-o group 1 vibrio cholerae septicemia in israel. 19938454453
gene encoding zonula occludens toxin (zot) does not occur independently from cholera enterotoxin genes (ctx) in vibrio cholerae.of 167 vibrio cholerae isolates screened for sequences homologous with zonula occludens toxin (zot) or cholera toxin (ctx) genes, 3.0% of non-o1, 100.0% of clinical o1, and 0.0% of environmental o1 strains contained both zot and ctx. zot was present only in strains that were ctx positive; all ctx-positive strains carried zot. the absence of zot-positive, ctx-negative strains suggests zot is not an independent virulence factor for v. cholerae, although zot may play a role in the pathogenesis of t ...19938458975
comparison of vibrio cholerae serotype 01 strains isolated from patients and the aquatic environment.vibrio cholerae 01 strains of el tor and classical biotypes and ogawa and inaba serotypes were isolated from both patients and pond water, the latter used by the patients from whom the v. cholerae 01 strains had been isolated. paired strains, i.e. from the patient and from the pond used by the patient, were compared. all strains were found to be non-hydrophobic and agglutinating in ammonium sulphate (2.0-2.5 m). they demonstrated similar antibiogram patterns and plasmids were not detected. excep ...19938459488
effect of various digestive enzymes on the interaction of toxoplasma gondii with macrophages.the participation of resident, elicited, and activated macrophage surface components during internalization of tachyzoites of toxoplasma gondii was analyzed using neuraminidase, phospholipase c, trypsin, protease, and hyaluronidase. treatment of these macrophages with neuraminidase from vibrio cholerae, phospholipase c from bacillus cereus and clostridium perfringens, protease, and hyaluronidase prior to their interaction with parasites increased the penetration of host cells by t. gondii. incub ...19938475028
ctx genetic element encodes a site-specific recombination system and an intestinal colonization factor.in vibrio cholerae, the genes encoding cholera toxin (ctxab) are located on a segment of dna (termed the "core" region) that is flanked by two or more copies of a repeated sequence called rs1. together these dna units comprise the ctx genetic element. evidence presented here suggests that rs1 sequences encode a site-specific recombination system, which allows integration of a suicide plasmid carrying rs1 into an 18-base-pair sequence (attrs1) located on the chromosome of nontoxigenic v. cholerae ...19938475125
coordinate regulation of siderophore and exotoxin a production: molecular cloning and sequencing of the pseudomonas aeruginosa fur gene.a 5.9-kb dna fragment was cloned from pseudomonas aeruginosa pa103 by its ability to functionally complement a fur mutation in escherichia coli. a fur null mutant e. coli strain that contains multiple copies of the 5.9-kb dna fragment produces a 15-kda protein which cross-reacts with a polyclonal anti-e. coli fur serum. sequencing of a subclone of the 5.9-kb dna fragment identified an open reading frame predicted to encode a protein 53% identical to e. coli fur and 49% identical to vibrio choler ...19938478325
activity of four fluoroquinolones against 346 strains of enteric pathogens. 19938486583
development of an enzyme-labeled oligonucleotide probe for the cholera toxin gene.an alkaline phosphatase-conjugated 30-mer oligonucleotide probe was developed to detect the cholera toxin gene (ctx) in vibrio cholerae o1. for rapid identification, v. cholerae o1 was grown on selective agar (thiosulfate-citrate-bile salts agar) or in alkaline peptone water and organisms were transferred directly to nylon membranes. lysis of cells, denaturation of dna, neutralization, and hybridization were carried out on the membrane. these procedures required only 3 h for completion. the resu ...19938501233
epidemic of diarrhea caused by vibrio cholerae non-o1 that produced heat-stable toxin among khmers in a camp in thailand.an epidemic of a cholera-like disease occurred among khmers in a camp in aranyaprathet, thailand, in may 1990. of 215 patients with diarrhea, vibrio cholerae o1 was isolated from 25 (12%) and v. cholerae non-o1 was isolated from 15 (7%). five of 15 (33%) non-o1 v. cholerae isolates hybridized with two different oligonucleotide probes previously used to detect v. cholerae non-o1 that produces a heat-stable toxin. this is the first description of an epidemic of diarrhea caused by v. cholerae non-o ...19938501234
an outbreak of cholera in maryland associated with imported commercial frozen fresh coconut milk.in august 1991, the first outbreak of cholera associated with an imported commercial food product occurred among persons attending a private picnic. an epidemiologic investigation showed infection with toxigenic vibrio cholerae o1, biotype el tor, serotype ogawa, in 4 of 6 persons who had consumed coconut milk imported from thailand. in addition, the us food and drug administration recovered toxigenic v. cholerae o1, biotype el tor, serotype ogawa, from 1 of 6 unopened bags of the same brand (bu ...19938501322
effect of sodium chloride, ph and organic nutrients on the motility of vibrio cholerae non-01.using a simple method of semi-solid agar (0.2%) in u-tubes, the effect of temperature, nacl, ph and nutrients on the motility of environmental vibrio cholerae non-01 was elucidated. under aerobic respiration succinate and pyruvate, which are metabolic intermediates, increased the motility rate, with succinate having the greatest influence. glucose and benzoic acid reduced the motility rate of most of the strains. optimum motility was obtained at ph 8.6 and 9.1 in all strains examined. acidic ph ...19938502172
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