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membrane insertion of the bacterial signal transduction protein toxr and requirements of transcription activation studied by modular replacement of different protein substructures.the vibrio cholerae protein toxr is an integral membrane protein that acts as a transcription activator in response to environmental signals; it controls expression of toxin genes ctxa and ctxb, along with a variety of other genes related to pathogenicity. here it is shown that: (i) toxr has a modular architecture and that activation of transcription starting at the ctx promoter depends strictly on dimerization of the periplasmic toxr domain; (ii) the transmembrane (tm) region of toxr is suffici ...19957664730
the first epidemic of vibrio cholerae o139. 19957665689
cell-surface charge and cell-surface hydrophobicity of collagen-binding aeromonas and vibrio strains.partitioning in aqueous polymer two-phase systems of polyethylene glycol and dextran was used to detect and compare cell-surface charge and cell-surface hydrophobicity of aeromonas hydrophila, a. caviae, a. sobria, vibrio cholerae, and v. anguillarum strains. these strains have cell-surface components that bound either native or thermally denatured type i collagen (i.e., a mixture of the alpha1+alpha2 chains) and gelatin immobilized on latex beads. our goals were: (1) to compare the possible rel ...19957668930
[choice of commercial elective nutrient media for the isolation of pathogenic vibrios of different species].commercial nutrient media and their modifications are assessed, including elective differentiation medium for v. cholerae developed at the rostov research anti-plague institute for the isolation of pathogenic vibrios. v. cholerae cholerae p-1 (145), v. cholerae el tor m-878, v. cholerae non 01 p-9741, e. coli 18, p. vulgaris 19, and 48 strains of vibrios belonging to different species were used in the study. all the strains used were characterized as to their nutritive requirements. alkaline aga ...19957670825
emergence of furazolidone and cotrimoxazole resistant vibrio cholerae 01 in eastern india. 19957673756
pathologic changes of gut in non-01 vibrio cholerae infection.a 14-year-old girl who had beta-thalassemia hemoglobin e disease was infected by bacteriologically proven non-01 vibrio cholerae at 2 months postsplenectomy and died 37 hours after onset of the malady. postmortem examination disclosed congestion, edema, and hemorrhagic foci of the mucosa of the small and large intestines. the gut mucosa was focally eroded. the gut wall was infiltrated by leucocytes, especially neutrophils, in all coats representing acute purulent and hemorrhagic enterocolitis. t ...19957673807
neuraminidase is essential for fowl plague virus hemagglutinin to show hemagglutinating activity.when hemagglutinin (ha) of fowl plague virus (fpv) was expressed in cv-1 cells by a simian virus 40 vector, hemadsorption was barely detectable, although ha was exposed at the cell surface. however, treatment of ha-expressing cells with vibrio cholerae neuraminidase (vcna) resulted in extensive hemadsorption. vcna treatment enhanced the electrophoretic mobility of the ha1 subunit of ha, indicating the removal of sialic acid. when two oligosaccharides in the vicinity of the receptor binding site ...19957676651
temperature-induced recovery of vibrio cholerae from the viable but nonculturable state: growth or resuscitation?vibrio cholerae cells were incubated at 4 degrees c in nutrient-limited artificial seawater (asw) microcosms. plate counts declined from 8 x 10(5) to less than 2 c.f.u. ml-1 in about 23 d. when samples of microcosms were shifted to 30 degrees c, plate counts increased to 2.2 x 10(5) c.f.u. ml-1 in 72 h. an experiment was performed to determine whether culturable cells obtained after temperature upshifts were the result of 'resuscitation', or outgrowth, of nonculturable cells or of cell division ...19957704268
cholera.despite more than a century of study, cholera still presents challenges and surprises to us. throughout most of the 20th century, cholera was caused by vibrio cholerae of the o1 serogroup and the disease was largely confined to asia and africa. however, the last decade of the 20th century has witnessed two major developments in the history of this disease. in 1991, a massive outbreak of cholera started in south america, the one continent previously untouched by cholera in this century. in 1992, ...19957704895
clinical and immunologic characteristics of vibrio cholerae o139 bengal infection in north american volunteers.vibrio cholerae o139 bengal has recently emerged as a cause of epidemic cholera in asia. to evaluate clinical and immunologic responses to infection, v. cholerae o139 bengal ai1837 was administered to healthy adult north american volunteers. two of 4 persons ingesting 10(4) cfu became ill (incubation period, 48 h; mean diarrheal stool, 1873 g), as did 7 of 9 persons receiving 10(6) cfu (incubation period, 28 h; mean diarrheal stool, 4548 g). ill volunteers did not demonstrate a vibriocidal antib ...19957706818
a comparative study of the properties of vibrio cholerae o139, o1 and other non-o1 strains.vibrio cholerae o139 organisms isolated from different parts of india and from bangladesh were characterised with respect to their haemagglutination (ha) activity, plasmid content, cholera toxin (ct) production, cell surface protein and lipopolysaccharide (lps) profiles, and antigenic properties. of 28 v. cholerae o139 isolates tested, 14 (50%) were shown to agglutinate chicken erythrocytes; the ha activity was sensitive to d-mannose 0.1%. in parallel experiments, 12 (92.3%) of 13 v. cholerae o1 ...19957707332
identification of a 29 kda flagellar sheath protein in helicobacter pylori using a murine monoclonal antibody.the membrane-like flagellar sheath of helicobacter pylori is of unknown function and little is known of its composition. a murine monoclonal antibody to h. pylori, designated gf6, which reacts by immunoblot with a polypeptide with an apparent molecular mass of 29 kda was shown by immunogold-electron microscopy to label specifically the flagellar sheath structure. the antigen was detected by immunoblot using the monoclonal antibody in all 11 strains, of diverse geographic origin, so far tested. t ...19957711897
safety, immunogenicity, and efficacy of live attenuated vibrio cholerae o139 vaccine prototype.new vaccines are needed to prevent cholera caused by vibrio cholerae o139. attenuated v cholerae o139 vaccines were made by deleting multiple copies of the cholera-toxin genetic element from two virulent strains of the organism, mo10 and ai4456. the deletion mutants were further modified by insertion of a construct that encoded the b subunit of cholera toxin, thus generating strains bengal-3 and vri-16. a stable spontaneous non-motile derivative of bengal-3 was isolated and designated bengal-15; ...19957715293
survey of in vitro susceptibilities of vibrio cholerae o1 and o139 to antimicrobial agents.vibrio cholerae o139 (173 strains) and o1 (221 strains) were tested for their in vitro susceptibilities to 39 antimicrobial agents. both o139 and o1 strains were highly susceptible to azithromycin, cephems, minocycline, penems, and newer fluoroquinolones. o139 strains (94.8%), o1 indian el tor strains (97%), and bangladeshi el tor strains (50%) were highly resistant to streptomycin, sulfamethoxazole, and trimethoprim and moderately resistant to chloramphenicol and furazolidone, in sharp contrast ...19957695314
in vibrio cholerae serogroup o1, rfad is closely linked to the rfb operon.the rfad gene of escherichia coli encodes adp-l-glycero-d-mannoheptose-6- epimerase, an enzyme required for the biosynthesis of the lipopolysaccharide (lps) precursor adp-l-glycero-d- mannoheptose, associated with production of the core oligosaccharide. we have identified an rfad homologue in vibrio cholerae o1. this gene maps adjacent to the rfb region encoding o-antigen biosynthesis, but is transcribed divergently. the complete nucleotide sequence of rfad and the flanking dna has been determin ...19957698669
an antimicrobial abietane from the root of plectranthus hereroensis.a new abietane diterpene, 16-acetoxy-7 alpha, 12-dihydroxy-8,12-abietadiene-11,14-dione, has been isolated from the acetone extract of the root of plectranthus hereroensis and its structure established by spectroscopic means. this compound showed antibacterial activity against staphylococcus aureus and vibrio cholerae, and antiviral activity against herpes simplex type ii.19957766053
characterization of the hgba locus encoding a hemoglobin receptor from haemophilus ducreyi.haemophilus ducreyi can bind hemoglobin and use it as a source of heme, for which it has an obligate requirement. we previously identified and purified hgba, a hemoglobin-binding outer membrane protein from h. ducreyi. in this report, we describe the molecular cloning, expression, dna sequence, and mutagenesis of the structural gene for hgba, hgba. h. ducreyi and recombinant escherichia coli expressing hgba bound [125i]hemoglobin, establishing hgba as a receptor. insertions or deletions in the c ...19957768598
construction of nontoxic derivatives of cholera toxin and characterization of the immunological response against the a subunit.using computer modelling, we have identified some of the residues of the a subunit of cholera toxin (ct) and heat-labile toxin that are involved in nad binding, catalysis, and toxicity. here we describe the site-directed mutagenesis of the ct gene and the construction of ct mutants. nine mutations of the a subunit gene were generated. six of them encoded proteins that were fully assembled in the ab5 structure and were nontoxic; these proteins were ct-d53 (val-53-->asp), ct-k63 (ser-63-->lys), ct ...19957768621
aldb, an rpos-dependent gene in escherichia coli encoding an aldehyde dehydrogenase that is repressed by fis and activated by crp.escherichia coli aldb was identified as a gene that is negatively regulated by fis but positively regulated by rpos. the complete dna sequence determined in this study indicates that aldb encodes a 56.3-kda protein which shares a high degree of homology with an acetaldehyde dehydrogenase encoded by acod of alcaligenes eutrophus and an aldehyde dehydrogenase encoded by alda of vibrio cholerae and significant homology with a group of other aldehyde dehydrogenases from prokaryotes and eukaryotes. e ...19957768815
the sixth and seventh cholera pandemics are due to independent clones separately derived from environmental, nontoxigenic, non-o1 vibrio cholerae.the dna sequences of the asd genes from 45 isolates of vibrio cholerae (19 clinical o1 isolates, 2 environmental nontoxigenic o1 isolates, and 24 isolates with different non-o1 antigens) were determined. no differences were found within either sixth- or seventh-pandemic isolates; however, variation was found between the two forms and among the non-o1 isolates. o139 isolates had sequences identical to those of seventh-pandemic isolates. phylogenetic trees with vibrio mimicus as the outgroup sugge ...19957768818
impact of infection by helicobacter pylori on the risk and severity of endemic cholera.to evaluate the relationship between helicobacter pylori infection and the subsequent risk and severity of endemic vibrio cholerae o1 diarrhea among rural bangladeshis, 285 children and adults with cholera (cases) and 881 contemporaneously selected community controls were studied. cases and controls were contrasted for h. pylori infection, as manifested by serum igg anti-h. pylori antibodies. although the overall risk of cholera was not significantly increased among h. pylori-infected subjects, ...19957769312
[the use of a cholera coagulating diagnostic agent under the cholera epidemic conditions in dagestan].dried cholera diagnosticum for the slide coagglutination test was obtained. the diagnosticum, found to be highly active and specific, permitted the detection of vibrio cholerae in the analyzed material at a concentration of 10(6)-10(8) microbial cells/ml. the diagnosticum was used during cholera epidemic in daghestan for the detection and rapid identification of cholera vibrios. in all cases the positive results of the coagglutination test were confirmed by other investigation methods (no cases ...19957771138
[the routes of the spread of cholera in the shamil'skiĭ mountain district of dagestan].the routes of the spread of cholera were analyzed in 273 patients and vibrio carriers during the outbreak of cholera in a mountainous region of daghestan during the period of july 18 to september 4, 1994. cholera was found to spread mainly after funeral repasts and condolence visits accompanied by the dispensation of foodstuffs, transmission being realized through alimentary and contact routes. under the conditions of the absence of the centralized water supply system in mountain villages and th ...19957771145
[the cholera epidemic in mountainous regions of dagestan in relation to the probable role of the water factor in its spread].the follow-up of dynamics of cholera epidemic in 1994 was made in 4 mountain regions of daghestan with shared river system. there were 537 infection cases in these regions, which was equal to 1/4 from the total number of cholera patients in daghestan. the probability of cholera distribution by water way has been shown, which can be related to massive dissemination with v. cholerae in river, drink and waste water both from active, and from local (intrahospital) epidemic sources. vibrio's exit fro ...19957771149
[the characteristics of the antibacterial therapy for cholera in dagestan].wide circulation of antibiotic-resistant vibrio cholerae strains again gives prominence to the problem of etiotropic therapy. the results of the treatment of 428 persons infected with v.cholerae (237 cholera patients and 191 vibrio carriers) in different regions of daghestan during the outbreak of epidemic in 1994 are presented. the main criterion of the effectiveness of antibacterial therapy was the determination of the percentage of bacterial relapses. the sensitivity of 118 v.cholerae strains ...19957771151
[the characteristics of vibrio cholerae isolated in dagestan in 1994].a high degree of resistance to cholera diagnostic phages and carriership of prophages characteristic of v. cholerae eltor strains vct+ were shown to be the specific features v. cholerae isolated in daghestan during the period of june-october 1994. among the strains under study, isolated respectively in 12 and 18 out of 19 regions of daghestan, a high proportion was found to have resistance to tetracycline (65%) and chloramphenicol (28.6%). moreover, some strains were found to be resistant to fur ...19957771152
[the bacteriophage lysis-susceptibility properties of vibrio cholerae strains isolated in separate regions of dagestan in 1994].the study of the properties of v. cholerae strains isolated in june-september 1994 in the daghestan revealed that they belonged, according to their specific properties, to typical representatives of v. eltor, serovar ogawa, but a great part of them (67.2%) was not lysed by diagnostic cholera bacteriophages. experiments with different batches of diagnostic cholera bacteriophages showed the necessity of their further improvement.19957771153
[the preservation of the causative agent of cholera in the water supplies of the central regions of dagestan (experimental data)].the acidic ph of water of surface water reservoirs in izberbash and two adjoining regions, including sea water, seems to be unfavorable for the prolonged preservation of vibrio cholerae eltor, but additional ecological investigations are necessary to study the possibility for infection to take root at this territory. water from the zam-zam spring, if contaminated with v. cholerae, may serve as a transmission factor, but the duration of its action is limited by the survival term of v. cholerae. t ...19957771154
[the properties of the vibrio cholerae strains isolated in large districts in western dagestan in 1994].190 v. cholerae cultures isolated by the specialized antiepidemic brigade of the rostov-on-don research institute for plague control in the khasavyurt, babayurt and novolaksk regions of daghestan in august-october 1994. all isolated strains were typical with respect to their morphological and cultural properties and could be agglutinated (with the exception of one strain) to the titer or half-titer with diagnostic cholera serum and ogawa serum. 4 strains had signs of ro-dissociation, 4 strains w ...19957771155
[the outer membranes of vibrio cholerae as a potential component in a chemical vaccine].the results of the study of the preparation of v. cholerae eltor membrane, obtained by the lysis and inactivation of microbial cells with urea and the subsequent differential centrifugation and nuclease treatment. as revealed in this study, the outer membrane preparation, when introduced parenterally and orally to mice, induced pronounced immunity to experimental cholera infection and the production of vibriocidal antibodies in high titers. the treatment of v. cholerae eltor membranes with tryps ...19957771156
[the isolation of the vibrio cholerae dermotoxin and the characterization of its biological properties].the dermonecrotic factor (dermotoxin) inducing skin necrosis in rabbits has been isolated from v. cholerae strain b-53-2-38 and partially purified. dermotoxin has a molecular weight of about 110 kd and possesses pronounced cytotoxic and general toxic action, differing from that of enterotoxin. the introduction of this factor into the blood and peritoneum of laboratory animals causes their death.19957771158
[the destructive activity of vibrios]. 19957771159
[the discovery of a dermonecrotic factor in vibrio cholerae non o1 and other pathogenic vibrios]. 19957771160
[cases of intrahospital cholera infection]. 19957771162
[a case of the importation onto the territory of russia of cholera caused by a new serovar].materials on the import of rarely occurring vibrio cholerae, not belonging to group o1 of serovar o139, to the territory of russia are presented. the clinical picture of a cholera case is described and the biological properties of v. cholerae, serovar o139, are presented. a suggestion has been made concerning the appearance of a new v. cholerae serovar, capable of ousting v. cholerae eltor, the cause of the seventh pandemic.19957771163
utility of rapid monoclonal antibody-based coagglutination test for direct detection of vibrio cholerae o1 and/or o139 in stool samples. 19957772164
in situ accessibility of murine macrophage gangliosides.gangliosides are implicated in cell signal transduction. prior to investigating this phenomenon in macrophages, the in situ accessibility of gangliosides to macromolecules was assessed for peritoneal macrophages isolated from normal c3h/hen and endotoxin-hyporesponsive c3h/hej mice. c3h/hej resident and thioglycolate-elicited macrophage ganglioside patterns are the same as normal strains, and no strain differences in galactose oxidase accessibility for resident or thioglycolate-elicited macropha ...19957772869
studies on adhesion, haemagglutination and other biological properties of vibrio cholerae o139.the adhesive capabilities of eight vibrio cholerae o139 epidemic strains to isolated rabbit intestinal epithelial cells (riec) were observed to be high similar to those observed with a vibrio cholerae o1 strain isolated from patients. toxin production by the strains, measured by accumulation of fluid in rabbit ileal loop model, was high and the toxin was lethal as the animal expired within 6 h. culture filtrates of the strains exhibited the presence of vascular permeability factor which produce ...19957773236
clinical characteristics and risk factors for vibrio cholerae infection in children.surveillance was conducted during february and march 1991 in the pediatric emergency department of cayetano heredia hospital, lima, peru, to contrast the characteristics of children with epidemic cholera with those of children with noncholera-associated diarrhea. among 626 patients 14 years of age or younger, vibrio cholerae o1 was isolated from stool specimens of 310 patients (49%), more commonly from children older than 24 months of age (66%; p < 0.0001) than from younger children. cholera was ...19957776088
from the centers for disease control and prevention. cholera associated with food transported from el salvador--indiana, 1994. 19957776490
effect of iron and ph on the survival of vibrio cholerae in water.many physicochemical factors affect the survival of vibrio cholerae in the aquatic environment. an attempt was made to study the combined effect of ph and iron on the survival of v. cholerae in water in a laboratory environment. none of the 6 strains of v. cholerae used survived at ph 5.0; survival of all strains increased with increasing ph. the effect of ferric oxide on survival was significant for v. cholerae o1 only, not for non o1 strains. the longest survival of v. cholerae non o1 was 82 d ...19957778142
[the cellular fatty acid composition of bacteria in the family vibrionaceae].vibrio cholerae strains, serovar o1, biovar eltor, subtype ogawa, isolated from different sources, v. cholerae classica and nag vibrios have identical cell fatty acid composition with the prevalence of hexadecenoic, hexadecanoic and octadecenoic acids. v. parahaemolyticus and v. alginolyticus fatty acid profiles, being identical, are similar to v. cholerae profile, differing from it mainly by a higher content of dodecanoic acid. the similarity of the fatty acid profiles of aeromonas sp. and vibr ...19957778361
[bactericidal effect of hydrated lime in aqueous solution].this study determined the bactericidal effect of the supernatants of saturated solutions of common lime and of micronized calcium hydroxide (ca(oh)2) (1500 mg/l), which was used as a control, compared with disinfectants made of solutions of 0.33% colloidal silver (0.0016 mg/l), toluene sulfachloramine (41 mg/l) with sodium bicarbonate (9 mg/l), and sodium hypochlorite (5 mg/l). the test involved four strains of vibrio cholerae 01, v. parahaemolyticus, escherichia coli, salmonella typhimurium, sh ...19957779285
[the 8th cholera pandemic: vibrio cholerae serogroup 0139 (bengala strain)]. 19957779879
cloning and sequencing of a novel hemolysis gene of vibrio cholerae.a hemolysis gene (hlx) which lyses sheep erythrocytes on blood agar plates when expressed in escherichia coli was cloned from vibrio cholerae. the cloned gene is predicted to encode a polypeptide of 92 amino acid residues with a deduced molecular mass of 10,451. e. coli transformed with this gene lysed sheep, goose, horse and chicken erythrocytes but not those of guinea pig and human. the hlx gene was observed in classical- and el tor-biotype v. cholerae o1, v. cholerae non-o1, and v. mimicus, b ...19957781973
vibrio cholerae o139 in denmark. 19957783553
analysis of vibrio cholerae toxr function by construction of novel fusion proteins.the toxr protein is a transmembrane protein that regulates the expression of several virulence factors of vibrio cholerae. previous analysis of fusion proteins between toxr and alkaline phosphatase (toxr-phoa) suggested that toxr was active as a dimer. in order to determine whether dimerization of the toxr periplasmic domain was essential for activity, this domain was replaced by monomeric and dimeric protein domains. surprisingly, phoa (dimeric), beta-lactamase (monomeric, toxr-bla), or the leu ...19957783643
comparison of a reversed passive latex agglutination and a polymerase chain reaction for identification of cholera toxin producing vibrio cholerae o1.production of cholera toxin (ct) in aki medium and conservation of ct gene (ctx) of 49 strains of vibrio cholerae o1 were compared by reversed passive latex agglutination (rpla) and polymerase chain reaction (pcr). the production of ct agreed with conservation of the ctx in 48 out of the 49 strains. ten strains were positive, and 38 strains were negative by both methods. only one strain was negative in rpla and positive in pcr. this suggested that the combination of aki-sw and rpla is comparable ...19957783678
characterization of an enterotoxin produced by vibrio cholerae o139.a cholera-like enterotoxin was purified from vibrio cholerae o139 strain ai-1841 isolated from a diarrheal patient in bangladesh. its characteristics were compared with that of cholera toxins (cts) of classical strain 569b and el tor strain kt25. al-1841 produced as much toxin as o1 strains. the toxins were indistinguishable in terms of their migration profiles in conventional polyacrylamide gel disc electrophoresis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis and isoelectrofocusin ...19957783690
a discrete factor a is detected on vibrio cholerae non-o1, o:139 by laser flow cytometry.a new serogroup of vibrio cholerae non-o1, o:139, has been implicated in recent epidemics. it was scanned with a factor a-specific fluoresceine-conjugated monoclonal antibody, searching for antigen determinants by laser flow cytometry. first, a group of gram-negative 4-amine-4, 6 dideoxy-d-mannose antigen-related microorganisms were tested to assess monoclonal antibody cross reactions. later, a clear recognition of antigen determinants was found with this monoclonal antibody, on v. cholerae non- ...19957784729
heterologous antigen expression in vibrio cholerae vector strains.live attenuated vector strains of vibrio cholerae were derived from peru-2, a peruvian el tor inaba strain deleted for the cholera toxin genetic element and attrs1 sequences, which was developed as a live, oral vaccine strain. a promoterless gene encoding the shiga-like toxin i b subunit (slt-ib) was inserted in the v. cholerae virulence gene irga by in vivo marker exchange, such that slt-ib was under transcriptional control of the iron-regulated irga promoter. slt-ib was also placed under trans ...19957790086
presence of lysogenic phage in the outbreak strains of vibrio cholerae o139.four outbreak strains of vibrio cholerae o139 from endemic areas of india and bangladesh were found to carry lysogenic phage(s). all of these phage(s) produced turbid plaques characteristic of lysogeny on v. cholerae mak 757 (el tor, ogawa) cells as well as on their vca-1 lysogens but were unable to infect v. cholerae 154 (classical) cells, the universal host for all classical phages. colonies in the turbid plaques were o139 lysogens and these developed an auxotrophic requirement, mainly for pur ...19957791203
the history of live bacterial vaccines.recent developments have made it possible to construct non-reverting live bacterial vaccine candidates with defined deletions of two or more genes. such vaccines have proven safe and immunogenic in human volunteers. since the virulent parent strains are only pathogenic to man (s. typhi, s. flexneri, and v. cholerae), they pose no threat to the environment. besides holding promise as efficacious vaccines for protection against typhoid fever, bacillary dysentery and cholera, the attenuated strains ...19957796956
vibrio cholerae cvd103-hgr live oral attenuated vaccine: construction, safety, immunogenicity, excretion and non-target effects.in many controlled studies, cvd103-hgr has been shown to be safe and immunogenic and to offer a significant degree of protection against experimental cholera after a single dose. its minimal excretion and limited ability to compete and survive in various ecosystems indicate that this strain presents little risk to the environment. furthermore, the potential of cvd103-hgr to regain virulence by acquisition of the ct a or lt a gene is extremely remote even under optimal conditions. therefore, cvd1 ...19957796960
the emerging diversity of the electrophoretic types of vibrio cholerae in the western hemisphere.since the latin american cholera epidemic began in 1991, 447 isolates of vibrio cholerae o1 from the western hemisphere have been assayed by multilocus enzyme electrophoresis (mee) to determine allelic variation among 16 enzyme-encoding genes. two electrophoretic types (ets) were identified among toxigenic isolates from latin america: 323 were et 4, the et associated with the latin american epidemic, and 29 were et 3. twenty-three of these et 3 isolates had a distinctive antimicrobial resistance ...19957797907
summary of the 29th united states-japan joint conference on cholera and related diarrheal diseases. 19957798685
cholera associated with food transported from el salvador--indiana, 1994.since the onset of the cholera epidemic in latin america in 1991, most cases of cholera in the united states have occurred among persons traveling to the united states from cholera-affected areas or who have eaten contaminated food brought or imported from these areas. in december 1994, a cluster of cholera cases occurred among persons in indiana who had shared a meal of contaminated food brought from el salvador. this report summarizes the investigation of the cases conducted by the indiana sta ...19957746262
comparative trial of five antimicrobial compounds in the treatment of cholera in adults.to compare the efficacy of ciprofloxacin, erythromycin, nalidixic acid and pivmecillinam in the treatment of tetracycline-resistant strains of vibrio cholerae o1 in adults, a randomized, open, clinical trial was conducted. a tetracycline group was used for comparison. seventy-five adult men infected with v. cholerae o1 were randomly assigned to receive either 400 mg pivmecillinam or 500 mg of one of each of the other drugs. ciprofloxacin was given every 12 h and the others every 6 h for 3 d. the ...19957747291
extension of the volunteer challenge model to study south american cholera in a population of volunteers predominantly with blood group antigen o.the volunteer challenge model was used to study the virulence of strains of vibrio cholerae o1 el tor recently isolated from cases of cholera in south america. fifteen of the 24 volunteers (62%) were of blood group o, the group most prevalent in south america and the group at increased risk of more severe cholera. two el t or inaba strains and 2 el tor ogawa strains were given to volunteers at a dose of 1-2 x 10(6) colony-forming units. all 4 strains caused diarrhoea in 67-83% of volunteers. vol ...19957747315
homogentisic acid is the primary precursor of melanin synthesis in vibrio cholerae, a hyphomonas strain, and shewanella colwelliana.the enzyme p-hydroxyphenylpyruvate hydroxylase (hpph) is involved in pigmentation (pyomelanin) via homogentisic acid (hga). pyomelanin formation is correlated with hga production and expression of hpph in three disparate marine species: vibrio cholerae, a hyphomonas strain, and shewanella colwelliana. induction of pigmentation in v. cholerae 569b by nutrient limitation also correlated with production of hga.19957747976
a retrospective analysis of the madras epidemic of non-01 vibrio cholerae new serogroup 0139 bengal.during the recent epidemic of cholera in madras from october-december 1992, a total of 11,100 patients with acute secretory diarrhoea have been admitted to the communicable diseases hospital, madras, when compared to a total of 2,440 patients admitted during the pre-epidemic period studied between january - september 1992. a novel strain of non-01 v. cholerae was found to be the most predominant agent during the epidemic period. a representative sample of 84 non-01 strains isolated during the ep ...19957751049
evaluation of the monoclonal antibody-based kit bengal smart for rapid detection of vibrio cholerae o139 synonym bengal in stool samples.a monoclonal antibody-based test, bengal smart, was developed for rapid detection of vibrio cholerae o139 synonym bengal directly from stool specimens. the test, which takes about 15 min to complete, was used to screen 189 diarrheal stool specimens. the results were compared with those of a monoclonal antibody-based coagglutination test (coat) and the conventional culture methods used as the "gold standard" for detection of v. cholerae o139. the bengal smart test showed a sensitivity of 100% and ...19957751386
rapid detection of vibrio cholerae 0139 in faecal specimens by coagglutination.we compared the conventional culture method with the coagglutination (coa) test for detecting v. cholerae 0139 antigen in a 4 h faecal enrichment culture. the coa test reacted positively in all 13 culture positive stool specimens from patients with clinical cholera and negatively in all 23 culture negative specimens from non-diarrhoeal healthy controls. the test also did not show cross reaction with v. cholerae 01 antigen or with any of the enterobacterial antigens of the coliforms. the coa test ...19957729848
colonization ability & intestinal pathology of rabbits orally fed with vibrio cholerae o139 bengal.the colonization ability of a representative epidemic strain of v. cholerae o139 bengal was studied in the oral rabbit colonization model and the nature of colonization in the ileal and jejunal tissues was examined ultrastructurally. results of the colonization study and ileal loop assay indicated that the strain proliferates and colonizes the small intestine of the rabbit mucosal surface. further, the electronmicroscopic study revealed the disruptive effect of the strain on the apical membrane ...19957729849
outbreak due to vibrio cholerae e1 tor & serotype o139 in yavatmal (maharashtra) during june-july, 1994.a total of 65 strains of v. cholerae were isolated during june-july 1994 at yavatmal (maharashtra). of the 65 strains isolated, 62 were 01 el tor vibrios, while three were non 01 serotype 0139. the novel epidemic strain designated as 0139 reported during the outbreak in 1993, has been supplanted by the usual el tor vibrio during the present outbreak while 0139 serotype has remained sporadic.19957729850
emrr is a negative regulator of the escherichia coli multidrug resistance pump emrab.the emrab locus of escherichia coli encodes a multidrug resistance pump that protects the cell from several chemically unrelated antimicrobial agents, e.g., the protonophores carbonyl cyanide m-chlorophenylhydrazone (cccp) and tetrachlorosalicyl anilide and the antibiotics nalidixic acid and thiolactomycin. the mpra gene is located immediately upstream of this locus and was shown to be a repressor of microcin biosynthesis (i. del castillo, j. m. gomez, and f. moreno, j. bacteriol. 173:3924-3929, ...19957730261
vibrio cholerae o139 bengal: emergence of a new epidemic strain of cholera.in october 1992, a new strain of cholera, subsequently designated vibrio cholerae o139 bengal, was detected in madras, india. this strain spread rapidly through the indian subcontinent and has now been reported in many parts of asia, with additional cases identified in travelers to north american and the middle east. phylogenetically, v. cholerae o139 bengal is very closely related to "standard" v. cholerae o1 el tor strains; it produces cholera toxin and causes an illness identical that seen wi ...19957728355
haemagglutinating property & cell surface hydrophobicity of vibrio cholerae 0139.cell-associated haemagglutinating activity was detected in all the epidemic strains of v. cholerae 0139 and 01, isolated in different parts of the country, with erythrocytes from rabbit, rat, chicken and guinea pig. sheep erythrocytes were unresponsive to both groups of strains. while d-mannose, alpha-methyl-d-mannoside, glucosamine, n-acetyl-d-glucosamine, thyroglobuline were effective inhibitors of the haemagglutinating activity of the v. cholerae 0139 and 01 strains, galactose and n-acetyl-d- ...19957601494
[molecular epidemiological study on vibrio cholerae o139].genomic dna from 56 vibrio cholerae o139 strains isolated in various countries was digested with sfi i or not i and analyzed by pulsed-field gel electrophoresis (pfge). eight different pfge patterns were identified. although the patterns of a large majority of ct-gene-positive epidemic strains isolated in india, bangladesh and thailand were the same or similar, but were slightly different from those of two ct-positive strains from india and nepal. on the other hand, the patterns of ct-negative t ...19957602181
trypanosoma cruzi trans-sialidase: enhancement of virulence in a murine model of chagas' disease.trypanosoma cruzi, the etiological agent of chagas' disease, expresses a trans-sialidase at highest levels in infective trypomastigotes, where it attaches to the plasma membrane by a glycophosphoinositol linkage. bound enzyme sheds into the extracellular milieu in a soluble form. experiments performed in vitro suggest that the trans-sialidase participates in several parameters of t. cruzi-host interactions, like cell adhesion and complement resistance. however, the role that membrane-bound and s ...19957722448
all vibrio cholerae infections are not created equal. 19957723150
the vibrio cholerae hlyc gene encodes a protein that is related to lipases of pseudomonas species.the nucleotide sequence of the vibrio cholerae n16961 hlyc gene was determined. the hlyc gene encompasses 513 nucleotides that are predicted to encode a 171-amino acid protein with a calculated molecular weight of 18.2 kda. the predicted hlyc protein contains a region that is 93.5% similar to the substrate-binding/catalytic domain of the pseudomonas species triacylglycerol acylhydrolase (lipase). the proposed catalytic serine residue is also conserved in the hlyc protein. the contribution of the ...19957612931
isolation of sucrose late-fermenting and nonfermenting variants of vibrio cholerae o139 bengal: implications for diagnosis of cholera.the sucrose-containing selective medium thiosulfate-citrate-bile salt-sucrose agar missed a sucrose nonfermenting and four sucrose late-fermenting variant strains of vibrio cholerae o139 bengal from diarrheal stools. these strains were, however, correctly identified as v. cholerae o139 on a sucrose-deficient selective medium, taurocholate-tellurite-gelatin agar.19957615751
[studies on vibrio cholerae non-o1 isolated from diarrheal patients arrived from overseas].between the period january 1991 to june 1993, there were 23,976,238 travellers who arrived from overseas to narita airport, of which 20,501 stool specimens were collected from diarrheal patients for bacteriological examination, and infectious agents were detected from 2,751 cases (13.4%) including 250 cases (1.2%) of vibrio cholerae non-o1. countries suspected of infection of these patients were thailand, the most in number, and followed by indonesia, india and so on these mostly distributed in ...19957616008
decrease in culturability of vibrio cholerae caused by glucose.the culturability of vibrio cholerae o1 serotype inaba strain 569b was decreased by the addition of glucose to cell suspensions in starvation media. a similar effect was observed with sucrose, maltose, and fructose. we term this inhibitory effect glucose shock. it was not observed with arabinose or xylose or with carboxylates, such as acetate and pyruvate. no acidification of the medium occurred in the presence of these carbohydrates. glucose shock was prevented by the addition of nitrogen or ph ...19957618870
cholera: calamitous past, ominous future.from the pandemics of the 19th century to the recent disaster in goma, zaire, cholera has left an indelible mark on human and medical history. cholera pandemics in the 19th and 20th centuries drove the development of epidemiology as a serious science. cholera has continued to press advances in the concepts of disease ecology, basic membrane biology, and transmembrane signaling and in the application of scientific information to treatment design. furthermore, the lessons learned from the study of ...19957620035
attenuated live cholera vaccine strain cvd 103-hgr elicits significantly higher serum vibriocidal antibody titers in persons of blood group o.persons of blood group o are at increased risk of developing cholera gravis. in a randomized, placebo-controlled, double-blind safety-immunogenicity trial of live oral cholera vaccine cvd 103-hgr in 5- to 9-year-old chilean children, vibriocidal antibody seroconversion (74% overall) did not differ by blood group. however, the reciprocal geometric mean titer (gmt) in blood group o vaccines (gmt = 486) was higher than that in non-o vaccines (gmt = 179) (p < 0.02).19957822046
sequencing of the gene encoding the major pilin of pilus colonization factor antigen iii (cfa/iii) of human enterotoxigenic escherichia coli and evidence that cfa/iii is related to type iv pili.the plasmid-encoded structural gene cofa necessary for the production of the major pilin subunit of pilus colonization factor antigen iii (cfa/iii) of human enterotoxigenic escherichia coli was identified, and the nucleotide sequence of the gene was determined. cofa consists of 714 nucleotides encoding a 238-amino-acid protein (molecular weight of 25,309). cofa seems to be a precursor of cfa/iii pilin, because the first 23 residues of the n-terminal amino acid sequence of the purified cfa/iii pi ...19957822050
expression and purification of shiga-like toxin ii b subunits.shiga-like toxins (slts), which are produced by certain strains of escherichia coli, are composed of enzymatically active a and b subunit multimers responsible for the toxin's binding. we have previously purified large amounts of the slt-i b subunit by using a hyperexpression vector in vibrio cholerae under the control of the trc promoter. in this study we examined various expression vectors to maximize yields of the slt-ii b subunit. the slt-ii b subunit has been expressed by using both the t7 ...19957806370
simultaneous outbreak due to vibrio cholerae and shigella dysenteriae in kenya. 19957799734
diarrhoeal outbreak of vibrio cholerae 0139 from north india.epidemics of cholera caused by vibrio cholerae 01 occur regularly in india. until recently, vibrio cholerae non-01 have been the the causative agents of sporadic cases of gastroenteritis and septicaemia, especially in immunocompromised children. we describe a large outbreak of cholera-like illness from north india caused by vibrio cholerae non-01, later serotyped as vibrio cholerae 0139. forty-one of a total of 391 patients with acute diarrhoea during a 2-month period (may-july 1993) were identi ...19957756810
cloning and expression of vibrio cholerae dsba, a gene encoding a periplasmic protein disulphide isomerase. 19957758780
interaction between the autokinase epse and epsl in the cytoplasmic membrane is required for extracellular secretion in vibrio cholerae.vibrio cholerae secretes a number of proteins important for virulence, including cholera toxin. this process requires the products of the eps genes which have homologues in genera such as aeromonas, klebsiella and pseudomonas and are thought to form a membrane-associated multiprotein complex. here we show that the putative nucleotide-binding protein epse is associated with and stabilized by the cytoplasmic membrane via interaction with epsl. analysis of fusion proteins between epse and the homol ...19957737119
detection of heat-stable enterotoxin genes among australian vibrio cholerae o1 strains.dna probes derived from the heat-stable enterotoxin gene of vibrio cholerae non-o1 (stn), and the cholera toxin gene (ctx), were used to screen 199 strains of v. cholerae o1, which were isolated within australia from 1977-1986. 13 environmental strains isolated from the riverine environment in southeast queensland in 1980 and 1981, hybridized with the stn and ctx dna probes. the concentrated supernatant of 6 of these strains elicited fluid accumulation in the infant mouse assay both before and a ...19957737472
isolation and characterization of the vibrio cholerae acfa gene, required for efficient intestinal colonization.the nucleotide sequence of the vibrio cholerae acfa gene (encoding an accessory colonization factor) has been determined. sequence analysis revealed the presence of an open reading frame of 215 amino acids with a characteristic signal peptidase i (spi) cleavage site at the n terminus. electrophoretic analysis of proteins synthesized by escherichia coli cells, following t7 promoter/rna polymerase-directed expression of acfa, revealed a 23-kda protein corresponding to the mature form of acfa. the ...19957737517
studies on the genesis of vibrio cholerae o139: identification of probable progenitor strains.four lines of evidence suggest that the recent outbreak strains of vibrio cholerae o139 could have emerged from serogroup o1 strains typified by isolates m01 and m0477 described in this paper, which are neither truly classical nor truly e1 tor in their biotype attributes. firstly, like all o139 isolates, these o1 strains, isolated in madras during and before the o139 outbreak, were resistant not only to polymyxin b but also to all biotype-specific choleraphages, i.e. classical phage phi 149 and ...19957739019
coexistence of vibrio cholerae o1 and o139 bengal in plankton in bangladesh. 19957739342
myff, an element of the network regulating the synthesis of fibrillae in yersinia enterocolitica.the yersinia enterocolitica surface antigen myf is a fibrillar structure that resembles cs3 fimbriae. gene myfa encodes the 21-kda major subunit of the antigen, while genes myfb and myfc are required for the transport and assembly of pilin subunits at the bacterial cell surface. here we show that the expression of myf is regulated at the transcriptional level by temperature and ph. gene myfa is transcribed at 37 degrees c and in acidic medium. the transcription start is preceded by a putative -1 ...19957836309
preliminary structure determination of the capsular polysaccharide of vibrio cholerae o139 bengal al1837.vibrio cholerae o139 bengal has recently been identified as a cause of epidemic cholera in asia. in contrast to v. cholerae o1, v. cholerae o139 bengal has a polysaccharide capsule. as determined by high-performance anion-exchange chromatography and 1h nuclear magnetic resonance analysis, the capsular polysaccharide of v. cholerae o139 bengal strain al1837 has six residues in the repeating subunit; this includes one residue each of n-acetylglucosamine, n-acetylquinovosamine (quinac), galacturoni ...19957836323
genesis of the novel epidemic vibrio cholerae o139 strain: evidence for horizontal transfer of genes involved in polysaccharide synthesis.only vibrio cholerae strains of serotype o1 are known to cause epidemics, while non-o1 strains are associated with sporadic cases of cholera. it was therefore unexpected that the recent cholera epidemic in asia was caused by a non-o1 strain with the serotype o139. we provide evidence that o139 arose from a strain closely related to the causative agent of the present cholera pandemic, v. cholerae o1 el tor, by acquisition of novel dna which was inserted into, and replaced part of, the o antigen g ...19957835331
the deduced vibrio cholerae reca amino-acid sequence.the nucleotide sequence of the reca gene of vibrio cholerae (vc) has been determined. the amino acid (aa) sequence of the protein product is very similar to other known reca aa sequences. however, this sequence does not agree with a previously reported vc reca aa sequence [ghosh et al., nucleic acids res. 20 (1992) 372].19957828921
specificity of the protein secretory apparatus: secretion of the heat-labile enterotoxin b subunit pentamers by different species of gram- bacteria.the b-subunit pentamer(s) (etxbp) of escherichia coli heat-labile enterotoxin (lt) are secreted from vibrio cholerae via the general secretion pathway (gsp), but remain periplasmic in e. coli. in order to determine if other gram- bacteria were also able to secrete the extbp, the etxb gene, which encodes etxb was introduced into different bacteria. of the bacteria examined, most species of vibrio and aeromonas were able to secrete this protein through the outer membrane; other gram- genera, inclu ...19957828926
diversity of dna sequences among vibrio cholerae o139 bengal detected by pcr-based dna fingerprinting.vibrio cholerae o139, a causative agent of a large epidemic of cholera-like illness, has suddenly emerged and spread widely over several months. to investigate the characteristics unique to o139, traditional typing techniques for v. cholerae, such as biochemical characteristics, antibiotic susceptibility and detection of toxin production, were performed, with the result that 145 o139 strains, except for two o139 strains isolated from argentina and germany, were indistinguishable from o1 strains. ...19957896075
safety and immunogenicity of a live oral bivalent typhoid fever (salmonella typhi ty21a)-cholera (vibrio cholerae cvd 103-hgr) vaccine in healthy adults.the safety and immunogenicity of the live oral attenuated vaccine strains vibrio cholerae cvd 103-hgr and salmonella typhi ty21a were evaluated alone or in a combined bivalent formulation in four groups composed of 185 healthy european adults. all presentations were well tolerated. the serum anti-s. typhi lipopolysaccharide immunoglobulin g and immunoglobulin a antibody responses were comparable for all groups (66 to 72% seroconversion). the serum vibriocidal antibody seroconversion rate ranged ...19957890391
isolation and characterization of a vibrio cholerae gene (taga) that encodes a toxr-regulated lipoprotein.the vibrio cholerae (vc) gene (taga) coding for the taga lipoprotein has been isolated. sequencing of taga revealed the presence of an open reading frame (orf) of 568 amino acids with a characteristic signal peptidase ii cleavage site at the n terminus. electrophoretic analysis of proteins synthesized by escherichia coli (ec) cells following t7 promoter/rna polymerase-directed expression of taga, revealed a closely migrating doublet of proteins corresponding to two species of taga. computer-gene ...19957883190
a new mobilizable cosmid vector for use in vibrio cholerae and other gram-negative bacteria.a new mobilizable cosmid vector, pcos5, was engineered for use in vibrio cholerae (vc). plasmid pcos5 is small in size (7286 bp), contains the orit from plasmid rk2, and has several unique restriction sites. the complete nucleotide sequence of pcos5 was deduced from the dna fragments used in its construction. biparental matings using escherichia coli (ec) sm10 and triparental matings using ec dh5 alpha[prk2013] were used to measure the conjugation frequency of pcos5 and pajm1, a clone containing ...19957883191
the spread of vibrio cholerae o139 in india. 19957876637
detection and differentiation of the gene for toxin co-regulated pili (tcpa) in vibrio cholerae non-o1 using the polymerase chain reaction.the polymerase chain reaction has been used to differentiate the gene which encodes the toxin co-regulated pili (tcpa) of the el tor and classical biotypes of vibrio cholerae o1. the same pcr primers were applied to strains belonging to non-o1 serogroups that produced cholera toxin. the size of fragment amplified was either identical to the tcpa of biotype el tor (471 bp) or to the tcpa of biotype classical (617 bp). all strains belonging to the novel epidemic serogroup o139 generated a 471-bp f ...19957875567
a 25-kda beta-lactam-induced outer membrane protein of vibrio cholerae. purification and characterization.a 25-kda outer membrane protein, induced following treatment of vibrio cholerae cells with beta-lactam antibiotics and constituting about 8-10% of the total outer membrane proteins of beta-lactam-resistant mutants, has been purified to homogeneity. it is a basic (pi 8.5) protein rich in beta-sheet structure and is a homodimer, the monomers being held together by hydrophobic interactions. the effective hydrophobicity of the protein is low, and a large part of the protein is exposed on the surface ...19957852369
inter-strand cross-linking of vibrio cholerae dna induced by furazolidone: a quantitative assay by four simple methods.four simple methods, i.e., (i) uv absorption spectrophotometry, (ii) hydroxyapatite chromatography, (iii) fluorescence analysis of ethidium bromide bound to dna and (iv) assay of s1 endonuclease action, were used in parallel for the estimation of furazolidone-induced inter-strand cross-links in vibrio cholerae dna. the data produced by the four methods were in reasonable agreement with each other and provided similar linear dose-response relations, the correlation (between dose and response) coe ...19957870098
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