Publications

the role of different protein components from the haemophilus ducreyi cytolethal distending toxin in the generation of cell toxicity.	cytolethal distending toxin of haemophilus ducreyi (hdcdt) is a multicomponent toxin, encoded by an operon consisting of three genes, cdtabc. to investigate the role of the individual products in generation of toxicity, recombinant plasmids were constructed allowing expression of each of the genes individually or in different combinations in escherichia coli and vibrio cholerae. expression of all three genes (cdtabc) was necessary to generate toxicity on cells, and no activity was obtained using ...	2001	11399138
lessons to be learned from studying vibrio cholerae in model systems.		2001	11532208
a secreted aminopeptidase of pseudomonas aeruginosa. identification, primary structure, and relationship to other aminopeptidases.	using leucine-p-nitroanilide (leu-pna) as a substrate, we demonstrated aminopeptidase activity in the culture filtrates of several pseudomonas aeruginosa strains. the aminopeptidase was partially purified by deae-cellulose chromatography and found to be heat stable. the apparent molecular mass of the enzyme was approximately 56 kda; hence, it was designated ap(56). heating (70 degrees c) of the partially purified aminopeptidase preparations led to the conversion of ap(56) to a approximately 28-k ...	2001	11533066
[prevalence of major virulence genes among various vibrio cholerae el-tor strains for evaluating their epidemiological significance].	specific oligonucleotide primers were chosen for identifying the fragments of the four major virulence genes of v. cholerae eltor (ctxa, tcpa, toxr, and hap) using the polymerase chain reaction (pcr). in order to estimate the efficiency of complex pcr testing of v. cholerae for evaluation of their epidemiological significance, a collection of 80 v. cholerae eltor strains with known virulence was selected, whose most important specific features had been studied previously. the hap was appropriate ...	2001	11534395
vibrio cholerae tolc is required for bile resistance and colonization.	tolc and its homologues are outer membrane proteins that are essential for the transport of many molecules across the cell envelope. in this study we characterized the gene encoding vibrio cholerae tolc. v. cholerae tolc mutants failed to secrete the rtx cytotoxin, were hypersensitive to antimicrobial agents, and were deficient in intestinal colonization.	2001	11402016
identification, characterization, and functional analysis of a gene encoding the ferric uptake regulation protein in bartonella species.	environmental iron concentrations coordinately regulate transcription of genes involved in iron acquisition and virulence via the ferric uptake regulation (fur) system. we identified and sequenced the fur gene and flanking regions of three bartonella species. the most notable difference between bartonella fur and other fur proteins was a substantially higher predicted isoelectric point. no promoter activity or fur autoregulation was detected using a gfp reporter gene fused to the 204 nucleotides ...	2001	11544240
regulation of aromatic amino acid biosynthesis in gamma-proteobacteria.	computational comparative techniques were applied to analysis of the aromatic amino acid regulons in gamma-proteobacteria. this resulted in characterization of the trpr and tyrr regulons in the genomes of yersinia pestis, haemophilus influenzae, vibrio cholerae and other bacteria and identification of new members of the phhr regulon in the genome of pseudomonas aeruginosa. candidate attenuators were constructed for all studied genomes, including the trpba operon of the very distantly related bac ...	2001	11545272
isolation and characterization of a temperature-sensitive generalized transducing bacteriophage for vibrio cholerae.	cp-t1 is the only described generalized transducing bacteriophage for the intestinal pathogen vibrio cholerae, yet many of its basic biological parameters remain unknown. due to low frequencies of transduction and pseudolysogen formation, cp-t1 has not been widely used as a genetic tool. to overcome these limitations, we have isolated a conditional mutant of cp-t1 that exhibits temperature-sensitive plaque formation. several biological properties of cp-t1ts were determined, including its restric ...	2001	11438186
[isolation and phenotyping of vibrio cholerae strains with the enhanced production of main protective antigens].	two v. cholerae strains of classical biovar, 2414 (serovar ogawa) and 2415 (serovar inaba), with of increased production of main protective antigens--cholera toxin, toxin-coregulated pili of adhesion (tcp), outer membrane protein ompu, as well as phospholipases and proteases, have been detected among natural and recombinant strains under study. a simultaneous increase in the production of the above-mentioned main immunogenicity factors in strains 2414 and 2415 is seemingly linked with the presen ...	2001	11548254
[comparative pathomorphological assessment of the action of vibrio cholerae serogroups 01 and 0139].	the pathomorphological picture of experimental infection caused by the infective agent of cholera was shown to have some specific features observed in infections caused by vibrios belonging to the serogroups under study. infection caused by v. cholerae of serogroup o139 induced some morphological changes in the gastrointestinal tract which were quite characteristic of this disease, but inflammatory changes with the prevalence of proliferative infiltrative processes came to the foreground simulta ...	2001	11548262
[experimental evaluation of efficacy of lactobacilli in prophylaxis and treatment of cholera].	investigations on experimental models of cholera ("sealed" mice and suckling rabbits) demonstrated that previous daily oral administration of the ferment culture of lactobacillus acidophilus bkm b-2020[symbol: see text] in a dose of 3.0 x 10(8) microbial cells/ml daily for 5-7 days prevented to the development of vibrio cholerae infection. the curative effect observed after 3 administrations of lactobacilli within 48 hours after infection with v. cholerae was registered in 50% of cases. this str ...	2001	11548265
lumen geometry of ion channels formed by vibrio cholerae el tor cytolysin elucidated by nonelectrolyte exclusion.	vibrio cholerae el tor cytolysin, a water-soluble protein with a molecular mass of 63 kda, forms small pores in target cell membranes. in this communication, planar lipid bilayers under voltage clamp conditions were used to investigate the geometric properties of the pores. it was established that all cytolysin channels were inserted into membranes with the same orientation. sharp asymmetry in the i-v curve of fully open cytolysin channels persisting at high electrolyte concentrations indicated ...	2001	11334624
[isolation of vibrio strains in french coastal waters and infection with vibrio cholerae non-o1/non-o139].	although the incidence in france of v. cholerae non-o1/non-o139 infection in man has increased since 1996, it remains low (7 cases in 1999). after the death in 1994 of an immunodepressed patient presenting a skin lesion showing superinfection by a strain of non-o1/non-o139 v. cholerae following exposure to seawater, we examined 22 samples of sea-water collected from 20 french coastal areas (mediterranean coast).	2001	11346901
the smallest stowaways.		2001	11352003
cholera in the united states, 1995-2000: trends at the end of the twentieth century.	to evaluate recent trends in cholera in the united states, surveillance data from all cases of laboratory-confirmed toxigenic vibrio cholerae o1 and o139 infection reported to the centers for disease control and prevention between 1995 and 2000 were reviewed. sixty-one cases of cholera, all caused by v. cholerae o1, were reported. there was 1 death, and 35 (57%) of the patients were hospitalized. thirty-seven (61%) infections were acquired outside the united states; 14 (23%) were acquired throug ...	2001	11517445
the novel sigma54- and sigma28-dependent flagellar gene transcription hierarchy of vibrio cholerae.	the human pathogen vibrio cholerae is a highly motile organism by virtue of a polar flagellum. flagellar transcriptional regulatory factors have been demonstrated to contribute to v. cholerae virulence, but the role these factors play in the transcription hierarchy controlling flagellar synthesis has been unclear. the flagellar genes revealed by the v. cholerae genome sequence are located in three large clusters, with the exception of the motor genes, which are found in three additional location ...	2001	11260476
membrane bioenergetics and virulence: problems and prospects.		2001	11261940
conjugating oligosaccharides to proteins by squaric acid diester chemistry: rapid monitoring of the progress of conjugation, and recovery of the unused ligand.	samples that are periodically withdrawn from the mixture of a conjugation reaction can be analyzed on a picomolar scale without any work-up or pre-purification using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (seldi-tof ms) in combination with the proteinchip system. the technique provides rapid information about the increasing molecular mass of the glycoconjugate formed, thereby allowing termination of the process when the desired incorporation of the ligand o ...	2001	11269399
diminished diarrheal response to vibrio cholerae strains carrying the replicative form of the ctx(phi) genome instead of ctx(phi) lysogens in adult rabbits.	toxigenic vibrio cholerae strains are lysogens of ctx(phi), a filamentous bacteriophage which encodes cholera toxin (ct). following infection of recipient v. cholerae cells by ctx(phi), the phage genome either integrates into the host chromosome at a specific attachment site (attrs) or exists as a replicative-form (rf) plasmid. we infected naturally occurring attrs-negative nontoxigenic v. cholerae or attenuated (ctx(-) attrs negative) derivatives of wild-type toxigenic strains with ctx(phi) and ...	2001	11553546
vibrio cholerae-induced cellular responses of polarized t84 intestinal epithelial cells are dependent on production of cholera toxin and the rtx toxin.	to study the utility of in vitro-polarized intestinal cell monolayers for modeling vibrio cholerae-host cell interactions, we added live v. cholerae bacteria to the apical surfaces of polarized t84 cell monolayers and monitored changes in electrical properties. we found that both classical and el tor strains produce cholera toxin after addition to the monolayer, but induction is most likely due to medium components rather than bacterium-cell interactions. we also found that the rtx toxin is prod ...	2001	11553575
[the characterization of vibrio cholerae non-o1 strain causing perforative pan-peritonitis].	we report a case of a 53-year-old male with vibrio cholerae non-o1 (serotype o19) infection, resulting in perforative pan-peritonitis. the patient had a history of gastric cancer and a gastrectomy was performed one year prior. the patient had previously been admitted with nausea and vomiting and was diagnosed with a sub-ileus condition. he was provisionally discharged when his condition improved and during that period he ate raw fish caught locally in nagasaki prefecture, and several hours later ...	2001	11558133
[surveillance of various enteropathogenic bacteria from diarrheal cases during 1989-1999 in kobe city].	incidence of various enteropathogenic bacteria was examined from diarrheal faecal samples that were collected from the patients of kobe city general hospital and some station hospitals (23,862), and from overseas travelers (2,855) over a period of decade (1989-1999) in kobe. a total of 1,580 strains were isolated from domestic and 331 strains from overseas travelers. the results are as follows. 1) thirteen kinds of enteropathogenic bacteria were isolated from domestic diarrheal cases (6.6%). sal ...	2001	11712364
a case of intracerebral abscess caused by non-o1 vibrio cholerae.		2001	11714056
[comparative study of the diagnostic value of new cholera eltor bacteriophages ctx+, ctx-, and khdf-3, 4, and 5].	the comparative evaluation of the diagnostic value of new cholera eltor bacteriophages ctx+ and ctx-, as well as monophages x[symbol: see text]-3, 4, 5, demonstrated their high activity and specificity. using of these bacteriophages epidemic potential of 95% vibrio cholerae eltor strains ctx+ and 84.5% of v. cholerae eltor stains ctx- was determined. commercial monophages x[symbol: see text]-3, 4, 5 were inferior to bacteriophages ctx+ and ctx- in their diagnostic value: only 55% of strains havi ...	2001	11550565
[spread of zoonotic agents by foods of animal origin].	due to the expansion of the international trade with food, there is a great and increasing danger of transmitting zoonotic agents with these foods over long distances from one region to another. however, in concrete cases it is difficult to determine which zoonotic agents are transmitted through which foodstuffs and how great the emergency is. the worldwide distribution of most of these agents, the easing up of import controls for goods coming from certain export countries, and the abstinence fr ...	2001	11560117
molecular identification of pathogenicity genes and eric types in vibrio cholerae o1 epidemic strains from mozambique.	the phenotypic and genotypic profiles of the v. cholerae strains causing the mozambican 1997-8 epidemic were characterized to provide a reference for comparison with other epidemic strains. a total of 75 strains of v. cholerae o1 isolated in different provinces, were analysed. strains were characterized by pcr for detecting toxin genes (ctxa, zot and ace), virulence associated genes (tcpa. nanh, hlya and torr) and eric sequences. all v. cholerae strains were serotype o1, ogawa, biotype el tor. m ...	2001	11561970
growth and recovery of selected gram-negative bacteria in reconditioned wastewater.	previous reports indicate that escherichia coli o157:h7, salmonella spp., and vibrio cholerae can grow in nutrient-limited, reconditioned wastewater over the temperature range of 4 to 46 degrees c when the biological oxygen demand of this water is <2, while its coliform growth response (cgr) is >2. in the current study, we investigated the growth response of vibrio parahaemolyticus, shigella spp., vibrio vulnificus, and pseudomonas aeruginosa in water samples with a cgr of >2 over the temperatur ...	2001	11726156
vibrio cholerae o1 outbreak isolates in mozambique and south africa in 1998 are multiple-drug resistant, contain the sxt element and the aada2 gene located on class 1 integrons.	the characteristics of vibrio cholerae o1 biotype el tor, serotype ogawa isolates from outbreaks of cholera in 1998 amongst migrant workers in the south african provinces of gauteng and mpumalanga, on the border of mozambique, are reported. the isolates seem to have originated from the same clone since they are of two closely related bgli ribotypes. these ribotypes had a high similarity to ribotypes of v. cholerae o1 recently found in three south-east asian countries. isolates were resistant to ...	2001	11733467
towards a reliable objective function for multiple sequence alignments.	multiple sequence alignment is a fundamental tool in a number of different domains in modern molecular biology, including functional and evolutionary studies of a protein family. multiple alignments also play an essential role in the new integrated systems for genome annotation and analysis. thus, the development of new multiple alignment scores and statistics is essential, in the spirit of the work dedicated to the evaluation of pairwise sequence alignments for database searching techniques. we ...	2001	11734009
a human volunteer challenge model using frozen bacteria of the new epidemic serotype, v. cholerae o139 in thai volunteers.	a total of 35 volunteers were recruited for an irb-approved inpatient dose-escalation challenge. the goal was to identify a dose that produced an observed cholera attack rate > or =80% and an illness of sufficient severity during the defined study period such that the model would be useful for determining vaccine protection. volunteers were challenged in groups of 5 with v. cholerae o139 that had been reconstituted immediately before use. only 2 out of 5 volunteers who received the lowest dose ( ...	2001	11738758
three cases of bacteremia caused by vibrio cholerae o1 in blantyre, malawi.	we report three fatal cases of bacteremia (two adults, one neonate) caused by vibrio cholerae o1 (ogawa), which occurred in the context of a community outbreak of cholera diarrhea in blantyre, malawi. only four cases of invasive disease caused by v. cholerae o1 have previously been reported. we describe the clinical features associated with these rare cases and discuss their significance.	2001	11747744
characterization of the role of the toxr-modulated outer membrane porins ompu and ompt in vibrio cholerae virulence.	toxr, the transmembrane regulatory protein required for expression of virulence factors in the human diarrheal pathogen vibrio cholerae, directly activates and represses the transcription of two outer membrane porins, ompu and ompt, respectively. in an attempt to dissect the role of the ompu and ompt porins in viability and virulence factor expression, in-frame chromosomal deletions were constructed in the coding sequences of ompu and ompt of v. cholerae. two separate deletions were introduced i ...	2001	11371530
flagellum-independent surface migration of vibrio cholerae and escherichia coli.	surface translocation has been described in a large variety of microorganisms, including some gram-negative enteric bacteria. here, we describe the novel observation of the flagellum-independent migration of vibrio cholerae and escherichia coli on semisolid surfaces with remarkable speeds. important aspects of this motility are the form of inoculation, the medium composition, and the use of agarose rather than agar. mutations in several known regulatory or surface structure proteins, such as tox ...	2001	11371543
salmonella enterica serovar typhimurium dt104 displays a rugose phenotype.	rugose phenotypes, such as those observed in vibrio cholerae, have increased resistance to chlorine, oxidative stress, and complement-mediated killing. in this study we identified and defined a rugose phenotype in salmonella enterica serovar typhimurium dt104 and showed induction only on certain media at 25 degrees c after 3 days of incubation. incubation at 37 degrees c resulted in the appearance of the smooth phenotype. observation of the ultrastructure of the rugose form and a stable smooth v ...	2001	11526004
in search of natural substrates and inhibitors of mdr pumps.	the function of microbial mdrs remains a hotly debated subject. given the very broad substrate specificities of some mdrs, like the rnd pumps that can extrude all classes of amphipathic compounds (cationic, neutral, and anionic), it seems difficult to develop a rationale for pinpointing possible natural substrates of these translocases. at the same time, several clues can be used to guide our search for natural mdr substrates. one is the fact that amphipathic cations appear to be the preferred s ...	2001	11321580
trifluoperazine: a broad spectrum bactericide especially active on staphylococci and vibrios.	trifluoperazine showed some significant antimicrobial activity when tested against 293 strains from two gram-positive and eight gram-negative genera. minimum inhibitory concentrations of the drug were measured using an agar dilution technique. forty six of 55 strains of staphylococcus aureus were inhibited by 10-50 microg/ml of trifluoperazine. this drug also inhibited strains of shigella spp., vibrio cholerae and v. parahaemolyticus at a concentration of 10-100 microg/ml. other bacteria includi ...	2001	11691578
[ultrastructure of renal cortex in suckling rabbits with experimental cholera].	development of experimental cholera in suckling rabbits is associated with appearance of alterations in glomerular filtration and tubular reabsorption of renal cortex. ultrastructural changes of nephrons appear in the adhesion period and progress 24 hours later. in this case, particular vulnerability of the kidneys is associated with insufficient development of principal stages both in the cavity and membrane digestion in the gut, therefore, the kidney plays a role of one of the components of th ...	2001	11810923
comparative analysis of fur regulons in gamma-proteobacteria.	iron is an essential element for the survival and pathogenesis of bacteria. the strict control of iron homeostasis is mediated by the fur repressor, which is highly conserved among various bacterial species. here we apply the comparative genomics approach to analyze candidate fur-binding sites in the genomes of escherichia coli (k12 and o157:h7), salmonella typhi, yersinia pestis and vibrio cholerae. we describe a number of new loci encoding siderophore biosynthesis and transport proteins. a new ...	2001	11812853
[molecular genetic features of vibrio cholerae classica strains, that caused the asiatic cholera epidemic in russian in 1942].	molecular genetic features of vibrio cholerae classical strains which caused an epidemic of asian cholera in russia in 1942 have been studied for the first time. these strains had a high level of choleric toxin production and toxin-coregulated adhesion piles, the main virulence factors; all the strains were auxotrophs and needed purine and/or amino acids for growth in minimal medium. moreover, having hapa structural gene in the chromosome (according to polymerase chain reaction), they did not pr ...	2001	11816113
response and tolerance of toxigenic vibro cholerae o1 to cold temperatures.	survival and tolerance at cold temperatures, the differentially expressed cellular proteins, and cholera toxin (ctx) production were evaluated in vibrio cholerae o1. rapid loss of culturability and change to distinct coccoid morphology occurred when cultures of v cholerae 01 were exposed to 5 degrees c directly from 35 degrees c. also, cultures of v. cholerae first exposed to 15 degrees c for 2 h and then maintained at 5 degrees c failed to exhibit an adaptive response, instead a rapid loss of v ...	2001	11816983
genome size reduction through multiple events of gene disintegration in buchnera aps.	the evolution of the endosymbiont buchnera during its adaptation to intracellular life involved a massive reduction in its genome. by comparing the orthologous genes of buchnera, escherichia coli and vibrio cholerae, we show that the minimal genome size of buchnera arose from multiple events of gene disintegration dispersed over the whole genome. the elimination of the genes was a continuous process that began with gene inactivation and progressed until the dna corresponding to the pseudogenes w ...	2001	11672844
[lipid peroxidation and the antioxidant blood system in dynamics of pestilential and choleraic intoxication].	lipid peroxidation (lpo) and activity of antioxidant system were studied spectrophotometrically in white rats developing pestilential and choleraic intoxication achieved by intraperitoneal injection of plague autolysate of vaccine eb strain in dose equivalent to dl50, cholerain endotoxin in doses dl50 and dl25 as well as combined effect of choleraic endo- and enterotoxins. with progression of the intoxication, the levels of diene conjugates and malonic dialdehyde in blood plasma and erythrocytes ...	2001	11565292
solar disinfection of drinking water protects against cholera in children under 6 years of age.	we have previously reported a reduction in risk of diarrhoeal disease in children who used solar disinfected drinking water. a cholera epidemic, occurring in an area of kenya in which a controlled trial of solar disinfection and diarrhoeal disease in children aged under 6 had recently finished, offered an opportunity to examine the protection offered by solar disinfection against cholera.	2001	11567937
pathogenesis of infectious diarrhea.	a brief overview of some of the main features involved in normal physiological bi-directional absorption and secretion of fluid in the gut is given, including the nature and cellular location of key enzymes, ion pumps, symports, antiports and diffusion channels; the microanatomy of intestinal villous vasculature and the dynamics of villus blood flow, which together generate hypertonic zones in villus tip regions; and the production, differentiation, escalator movement (from crypt to villus tip) ...	2001	11694903
a novel method to calculate the g+c content of genomic dna sequences.	the base composition of a dna fragment or genome is usually measured by the proportion of a+t or g+c in the sequence. the g+c content along genomic sequences is usually calculated using an overlapping or non-overlapping sliding window method. the result and accuracy of such an approach depends on the size of the window and the moving distance adopted. in this paper, a novel windowless technique to calculate the g+c content of genomic sequences is proposed. by this method, the g+c content can be ...	2001	11697737
[analysis of toxin genetic determinants of vibrio cholerae virulence cassette and neuraminidase with dna probes].	v. cholerae strains of different origin have been studied for the presence of cholera toxin genes (vct), the proximal part of the virulence cassette including genes zot, ace and orfu, as well as neuraminidase genes (neu), in their genomes with the use of molecular dna probes. the possibility, in principle, for some strains to lose only a part of their virulence cassette (gene vct), while retaining its proximal part has been shown. in most cases such strains are isolated from patients with diarrh ...	2001	11548252
vibrio cholerae diarrhoea in a three-day-old breastfed neonate.	a confirmed case of cholera in a 3-day-old neonate is being reported. possible source of infection could be by holy water (chamamrit) given to the baby, which is common ritual in india. mother's milk has never been reported to transmit cholera, even though mother herself may be suffering from cholera. contaminated water can transmit the disease as there is no maternally transmitted immunity.	2001	11563260
epidemic of vibrio cholerae serogroup o139 in berhampur, orissa.	during the months of may-june 2000, 194 patients with watery diarrhoea were admitted to the infectious diseases ward of the m.k.c.g. medical college, berhampur. ninety four rectal swabs were collected and processed according to the standard procedures. vibrio cholerae strains were isolated from 20 samples. of these 20 isolates, two were found to be v. cholerae o1 eitor ogawa strain and 18 were confirmed to be v. cholerae serotype o139. all v. cholerae o139 isolates were of a single phage type (p ...	2001	11762200
[experiment observations of the germicidal effects of disinfectants on vibro cholerae of el tor biotype in different water bodies].	to study the germicidal effect of disinfectant on vibro cholerae of el tor biotype in different water bodies and to set a guidelines for disinfection in the epidemic foci of cholera.	2001	11769638
automatic analysis of image of surface structure of cell wall-deficient evc.	some computer applications for cell characterization in medicine and biology, such as analysis of surface structure of cell wall-deficient evc (el tor vibrio of cholera), operate with cell samples taken from very small areas of interest. in order to perform texture characterization in such an application, only a few texture operators can be employed: the operators should be insensitive to noise and image distortion and be reliable in order to estimate texture quality from images. therefore, we i ...	2001	11564900
cholera in indonesia in 1993-1999.	cholera-specific surveillance in indonesia was initiated to identify the introduction of the newly recognized vibrio cholerae non-o1, o139 serotype. findings from seven years (1993-1999) of surveillance efforts also yielded regional profiles of the importance of cholera in both epidemic and sporadic diarrheal disease occurrence throughout the archipelago. a two-fold surveillance strategy was pursued involving 1) outbreak investigations, and 2) hospital-based case recognition. rectal swabs were t ...	2001	11791976
[strategies of adaptive changes in vibrio cholerae in natural water reservoirs].	the currently available data on different variations in cholera vibrio habiting in water reservoirs are summarized. the pattern of variations of the main signs of vibrions is discussed in the context of "typical-atypical-inactive-resting (uncultivable) forms". emphasis is placed on the reversible pattern and adaptive essence of variation whose basis is clonal and selective processes in the heterogeneous bacterial population. possible populational mechanisms responsible for the development of epi ...	2001	11837201
viability of the nonculturable vibrio cholerae o1 and o139.	vibrio cholerae is capable of transforming into a viable but nonculturable (vbnc) state, and, in doing so, undergoes alteration in cell morphology. in the study reported here, vibrio cholerae o1 and o139 cells were maintained in laboratory microcosms prepared with 1% instant ocean and incubated at 4 degrees c, i.e., conditions which induce the vbnc state. cells were fixed at different stages during entry into the vbnc state and, when no growth was detectable on solid or in liquid media, the ultr ...	2001	11822667
stimulation of mucosal immune response following oral administration of enterotoxigenic escherichia coli fimbriae (cfa/i) entrapped in liposomes in conjunction with inactivated whole-cell vibrio cholerae vaccine.	in this study, we have searched for an effective mucosal vaccine. an oral enterotoxigenic e. coli vaccine containing colonization factor antigen (cfa/i) associated with inactivated whole-cell v. cholerae vaccine (wcv) has been tested for safety and immunogenicity in animals. five groups of animals were used. the results showed the following: (a) vaccine containing cfa/i antigen entrapped in liposomes and associated with wcv (batch c) had increased titers of specific antibodies to cfa/i antigen i ...	2001	11850896
pepa, a gene mediating ph regulation of virulence genes in vibrio cholerae.	toxt, a member of the arac family of transcriptional regulators, controls the expression of several virulence factors in vibrio cholerae. in the classical biotype of v. cholerae, expression of toxt is regulated by the same environmental conditions that control expression of the virulence determinants cholera toxin and the toxin coregulated pilus. several genes that activate toxt expression have been identified. to identify genes that repress toxt expression in nonpermissive environmental conditi ...	2001	11114915
in vitro susceptibility of vibrio cholerae o1 biotype el tor strains associated with an outbreak of cholera in kerala, southern india.		2001	11222575
syntheses of the l-manno and some other analogs of the terminal determinants of the o-ps of vibrio cholerae o:1.	analogs of the methyl alpha-glycosides of the terminal residues of the o-specific polysaccharides (o-ps) of vibrio cholerae o:1, serotype inaba and ogawa, have been prepared as probes to study their interaction with anti v. cholerae o:1 antibodies. they differ from the termini of the respective o-pss in anomeric or absolute configuration of perosamine, position of the o-methyl group in d-perosamine, and nature of the n-acyl side chain.	2001	11217964
evolution of the na-p(i) cotransport systems.	membrane transport systems for p(i) transport are key elements in maintaining homeostasis of p(i) in organisms as diverse as bacteria and human. two na-p(i) cotransporter families with well-described functional properties in vertebrates, namely napi-ii and napi-iii, show conserved structural features with prokaryotic origin. a clear vertical relationship can be established among the mammalian protein family napi-iii, a homologous system in c. elegans, the yeast system pho89, and the bacterial p( ...	2001	11208556
cell vacuolation caused by vibrio cholerae hemolysin.	non-o1 strains of vibrio cholerae implicated in gastroenteritis and diarrhea generally lack virulence determinants such as cholera toxin that are characteristic of epidemic strains; the factors that contribute to their virulence are not understood. here we report that at least one-third of diarrhea-associated nonepidemic v. cholerae strains from mexico cause vacuolation of cultured vero cells. detailed analyses indicated that this vacuolation was related to that caused by aerolysin, a pore-formi ...	2001	11179335
comparison of vibrio cholerae pathogenicity islands in sixth and seventh pandemic strains.	epidemic vibrio cholerae strains possess a large cluster of essential virulence genes on the chromosome called the vibrio pathogenicity island (vpi). the vpi contains the tcp gene cluster encoding the type iv pilus toxin-coregulated pilus colonization factor which can act as the cholera toxin bacteriophage (ctxphi) receptor. the vpi also contains genes that regulate virulence factor expression. we have fully sequenced and compared the vpi of the seventh-pandemic (el tor biotype) strain n16961 an ...	2001	11179381
the two tonb systems of vibrio cholerae: redundant and specific functions.	the two tonb systems in vibrio cholerae were found to have unique as well as common functions. both systems can mediate transport of haemin and the siderophores vibriobactin and ferrichrome. however, tonb1 specifically mediates utilization of the siderophore schizokinen, whereas tonb2 is required for utilization of enterobactin by v. cholerae. although either tonb system was sufficient for the use of haemin as an iron source, in vitro competition between tonb1 and tonb2 system mutants indicates ...	2001	11169119
purification and preliminary characterization of the zonula occludens toxin receptor from human (caco2) and murine (iec6) intestinal cell lines.	in the present study, we report the preliminary characterization of the epithelial cell receptor for vibrio cholerae zonula occludens toxin (zot). zot receptor was purified by ligand-affinity chromatography. analysis of affinity-purified preparations by polyacrylamide gel electrophoresis revealed a protein of ca. 66 kda. partial n-terminal sequence obtained from purified murine and human zot receptor revealed homology between the two proteins and with human alpha-1-chimaerin. zot protein domain( ...	2001	11150657
formation of chromosomal tandem arrays of the sxt element and r391, two conjugative chromosomally integrating elements that share an attachment site.	the sxt element, a conjugative, self-transmissible, integrating element (a constin) originally derived from a vibrio cholerae o139 isolate from india, and incj element r391, originally derived from a south african providencia rettgeri isolate, were found to be genetically and functionally related. both of these constins integrate site specifically into the escherichia coli chromosome at an identical attachment site within the 5' end of prfc. they encode nearly identical integrases, which are req ...	2001	11157923
identification of legionella pneumophila genes important for infection of amoebas by signature-tagged mutagenesis.	legionella pneumophila is a facultative intracellular gram-negative rod that causes pneumonia in humans. free-living amoebas are thought to serve as a reservoir for legionella infections. signature-tagged mutagenesis was employed to identify legionella pneumophila genes necessary for survival in the amoeba acanthamoeba castellanii. six mutant strains were defective in assays of invasion and intracellular growth. four mutants also exhibited invasion and replication defects in hartmannella vermifo ...	2001	11159993
vpsr, a member of the response regulators of the two-component regulatory systems, is required for expression of vps biosynthesis genes and eps(etr)-associated phenotypes in vibrio cholerae o1 el tor.	the rugose colonial variant of vibrio cholerae o1 el tor produces an exopolysaccharide (eps(etr)) that enables the organism to form a biofilm and to resist oxidative stress and the bactericidal action of chlorine. transposon mutagenesis of the rugose variant led to the identification of vpsr, which codes for a homologue of the ntrc subclass of response regulators. targeted disruption of vpsr in the rugose colony genetic background yielded a nonreverting smooth-colony morphotype that produced no ...	2001	11160103
a unique sialidase that cleaves the neu5gcalpha2-->5-o(glycolyl)neu5gc linkage: comparison of its specificity with that of three microbial sialidases toward four sialic acid dimers.	we found that the hepatopancreas of oyster, crassostrea virginica, contained a sialidase capable of releasing neu5gc from the novel polysialic acid chain (-->5-o(glycolyl)neu5gcalpha2-->)n more efficiently than from the conventional type of polysialic acid chains, (-->8neu5acalpha2-->)n, or (-->8neu5gcalpha2-->)n. we have partially purified this novel sialidase and compared its reactivity with that of microbial sialidases using four different sialic acid dimers, neu5gcalpha2-->5-o(glycolyl)neu5g ...	2001	11162485
sieve analysis: methods for assessing from vaccine trial data how vaccine efficacy varies with genotypic and phenotypic pathogen variation.	a key component in the evaluation of efficacy of a vaccine to protect against disease caused by an antigenically diverse infectious pathogen in a preventative vaccine trial is assessing how vaccine-induced protection depends on genotypic and phenotypic variations of the exposing pathogen. this assessment is made by comparing pathogen isolates between infected vaccinated subjects and infected unvaccinated subjects. a survey of efficacy trial reports reveals a lack of systematic, quantitative inve ...	2001	11165470
the absence of a flagellum leads to altered colony morphology, biofilm development and virulence in vibrio cholerae o139.	throughout most of history, epidemic and pandemic cholera was caused by vibrio cholerae of the serogroup o1. in 1992, however, a v. cholerae strain of the serogroup o139 emerged as a new agent of epidemic cholera. interestingly, v. cholerae o139 forms biofilms on abiotic surfaces more rapidly than v. cholerae o1 biotype el tor, perhaps because regulation of exopolysaccharide synthesis in v. cholerae o139 differs from that in o1 el tor. here, we show that all flagellar mutants of v. cholerae o139 ...	2001	11136445
the gdhb gene of pseudomonas aeruginosa encodes an arginine-inducible nad(+)-dependent glutamate dehydrogenase which is subject to allosteric regulation.	the nad(+)-dependent glutamate dehydrogenase (nad-gdh) from pseudomonas aeruginosa pao1 was purified, and its amino-terminal amino acid sequence was determined. this sequence information was used in identifying and cloning the encoding gdhb gene and its flanking regions. the molecular mass predicted from the derived sequence for the encoded nad-gdh was 182.6 kda, in close agreement with that determined from sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the purified enzyme (180 kda ...	2001	11133942
characterization of vibrio cholerae o1 el tor galu and gale mutants: influence on lipopolysaccharide structure, colonization, and biofilm formation.	recently we described the isolation of spontaneous bacteriophage k139-resistant vibrio cholerae o1 el tor mutants. in this study, we identified phage-resistant isolates with intact o antigen but altered core oligosaccharide which were also affected in galactose catabolism; this strains have mutations in the galu gene. we inactivated another gal gene, gale, and the mutant was also found to be defective in the catabolism of exogenous galactose but synthesized an apparently normal lipopolysaccharid ...	2001	11119535
differential interleukin-8 response of intestinal epithelial cell line to reactogenic and nonreactogenic candidate vaccine strains of vibrio cholerae.	in this study, we analyzed whether attachment of vibrio cholerae vaccine strains to human intestinal epithelial cells can induce an interleukin-8 (il-8) response. the il-8 transcripts were detected by pcr amplification of reverse-transcribed mrna, and the gene product secretion was measured by an enzyme-linked immunosorbent assay. infection of monolayers of the undifferentiated ht29-18n2 cell line with reactogenic (jbk70 and 81) and nonreactogenic (cvd103hgr and 638) vaccine strains of v. choler ...	2001	11119564
emergence of fluoroquinolone-resistant strains of vibrio cholerae o1 biotype el tor among hospitalized patients with cholera in calcutta, india.		2001	11372642
a novel surfactant nanoemulsion with a unique non-irritant topical antimicrobial activity against bacteria, enveloped viruses and fungi.	a novel non-ionic surfactant nanoemulsion designated 8n8 has been tested for its biocidal activity. one percent 8n8 produced effective bactericidal activity against bacillus cereus, bacillus subtilis, haemophilus influenzae, neisseria gonorrhoeae, streptococcus pneumoniae, and vibrio cholerae in 15 minutes. in contrast, most enteric gram-negative bacteria were resistant to 8n8. one percent 8n8 was also virucidal within 15 minutes for all tested enveloped viruses, including herpes simplex type 1, ...	2001	11372645
genotypes associated with virulence in environmental isolates of vibrio cholerae.	vibrio cholerae is an autochthonous inhabitant of riverine and estuarine environments and also is a facultative pathogen for humans. genotyping can be useful in assessing the risk of contracting cholera, intestinal, or extraintestinal infections via drinking water and/or seafood. in this study, environmental isolates of v. cholerae were examined for the presence of ctxa, hlya, ompu, stn/sto, tcpa, tcpi, toxr, and zot genes, using multiplex pcr. based on tcpa and hlya gene comparisons, the strain ...	2001	11375146
etiology of children's diarrhea in montevideo, uruguay: associated pathogens and unusual isolates.	we studied microorganisms associated with infant diarrhea in a group of 256 children admitted to a public pediatric hospital in montevideo, uruguay. diagnostic procedures were updated to optimize detection of potential pathogens, which were found in 63.8% of cases, and to be able to define their characteristics down to molecular or antigenic type. coinfection with two or more agents was detected in more than one-third of positive studies. escherichia coli enteric virotypes, especially enteropath ...	2001	11376047
structure of the o-specific polysaccharide of vibrio cholerae o9 containing 2-acetamido-2-deoxy-d-galacturonic acid.	the o-specific polysaccharide (ops) was isolated by mild-acid degradation of the lipopolysaccharide of vibrio cholerae o9 and studied by carboxyl reduction, sugar and methylation analyses, smith degradation, and two-dimensional nmr spectroscopy, including cosy, tocsy, noesy, and h-detected 1h,(13)c hmqc experiments. the following structure of the pentasaccharide-repeating unit of the ops was established:	2001	11376607
sira orthologs affect both motility and virulence.	the sira gene of salmonella enterica serovar typhimurium encodes a two-component response regulator of the fixj family that has a positive regulatory influence on the expression of type iii secretion genes involved with epithelial cell invasion and the elicitation of bovine gastroenteritis. sira orthologs in pseudomonas, vibrio, and erwinia control the expression of distinct virulence genes in these genera, but an evolutionarily conserved target of sira regulation has never been identified. in t ...	2001	11244064
cholera.	cholera, an infectious disease caused by vibrio cholerae, is primarily transmitted by ingestion of contaminated food or water. in severe cases, cholera may lead to severe dehydration, metabolic acidosis, and ultimately, hypovolemic shock and death. the diagnosis is confirmed by identification of v. cholerae in a stool specimen. treatment should be started immediately by rapid replacement of fluid and electrolytes. antibiotics such as tetracycline and doxycycline shorten the duration of illness b ...	2001	11378428
effects of cholera toxin on macrophage production of co-stimulatory cytokines.	cholera toxin (ct), the enterotoxin of vibrio cholerae, is a potent mucosal and systemic immunogen and adjuvant. the precise mechanism of the adjuvanticity of ct is poorly understood. our previous work has showed that ct up-regulates b7.2, but not b7.1 expression on macrophages, and thus increases their co-stimulatory activity. in the current study, the effects of ct on macrophage co-stimulatory cytokine production were investigated. bone marrow macrophages were generated by culturing bone marro ...	2001	11169439
vector potential of houseflies (musca domestica) in the transmission of vibrio cholerae in india.	it is well known that diarrhoeal infections due to vibrio cholerae are spread through fecal-oral route of transmission. in the present study an attempt was made to isolate and identify v. cholerae from houseflies, musca domestica collected from a low socioeconomic area in delhi, india, where an outbreak of cholera was encountered. of the ten fly pools examined, six (60%) were positive for v. cholerae. of these six pools, three (50%) showed v. cholerae ogawa t2 el tor and one (17.5%) v. cholerae ...	2001	11164748
antimicrobial-resistant bacterial diarrhea in rural western kenya.	bacterial diarrheal diseases cause substantial morbidity and mortality in sub-saharan africa, but data on the epidemiology and antimicrobial susceptibility patterns of enteric bacterial pathogens are limited. between may 1997 and april 1998, a clinic-based surveillance for diarrheal disease was conducted in asembo, a rural area in western kenya. in total, 729 diarrheal specimens were collected, and 244 (33%) yielded >or=1 bacterial pathogen, as determined by standard culture techniques; 107 (44% ...	2001	11343224
identification and functional characterization of arylamine n-acetyltransferases in eubacteria: evidence for highly selective acetylation of 5-aminosalicylic acid.	arylamine n-acetyltransferase activity has been described in various bacterial species. bacterial n-acetyltransferases, including those from bacteria of the gut flora, may be involved in the metabolism of xenobiotics, thereby exerting physiopathological effects. we characterized these enzymes further by steady-state kinetics, time-dependent inhibition, and dna hybridization in 40 species, mostly from the human intestinal microflora. we report for the first time n-acetyltransferase activity in 11 ...	2001	11344150
vibd and vibh are required for late steps in vibriobactin biosynthesis in vibrio cholerae.	vibrio cholerae synthesizes the catechol siderophore vibriobactin. in this report, we present the complete map of a vibriobactin gene region containing two previously unreported vibriobactin biosynthetic genes. vibd encodes a phosphopantetheinyl transferase, and vibh encodes a novel nonribosomal peptide synthase. both vibd and vibh are required for vibriobactin biosynthesis.	2001	11160122
local and systemic immune responses to rectal administration of recombinant cholera toxin b subunit in humans.	the induction of immune responses to rectally administered recombinant cholera toxin b subunit (ctb) in humans was studied. three immunizations induced high levels of ctb-specific antibody-secreting cells, particular of the immunoglobulin a isotype, in both rectum and peripheral blood. antitoxin antibody responses in rectal secretions and serum were also found.	2001	11349086
rna arbitrarily primed pcr survey of genes regulated by toxr in the deep-sea bacterium photobacterium profundum strain ss9.	we are currently investigating the role of toxr-mediated gene regulation in photobacterium profundum strain ss9. ss9 is a moderately piezophilic ("pressure loving") psychrotolerant marine bacterium belonging to the family vibrionaceae. in vibrio cholerae, toxr is a transmembrane dna binding protein involved in mediating virulence gene expression in response to various environmental signals. a homolog to v. cholerae toxr that is necessary for pressure-responsive gene expression of two outer membr ...	2001	11160100
regulation of metalloprotease gene expression in vibrio vulnificus by a vibrio harveyi luxr homologue.	expression of the vibrio vulnificus metalloprotease gene, vvp, was turned up rapidly when bacterial growth reached the late log phase. a similar pattern of expression has been found in the metalloprotease gene of vibrio cholerae, and this has been shown to be regulated by a vibrio harveyi luxr-like transcriptional activator. to find out whether a luxr homologue exists in v. vulnificus, a gene library of this organism was screened by colony hybridization using a probe derived from a sequence that ...	2001	11157950
vibrio cholerae non-o1 facial cellulitis in a north queensland, australian child.	vibrio cholerae is an uncommon cause of cellulitis in australia. most reported cases worldwide have involved marine or brackish water contact. a recognized risk factor for acquiring this infection is chronic liver disease secondary to hepatitis b. we describe a case of extensive facial cellulitis caused by vibrio cholerae non-o1, non-0139, in an 11-year-old indigenous girl from north queensland, australia, who was hepatitis b surface antigen-negative. treatment consisted of extensive debridement ...	2001	11368121
molecular analysis of vibrio cholerae o1, o139, non-o1, and non-o139 strains: clonal relationships between clinical and environmental isolates.	a total of 26 strains of vibrio cholerae, including members of the o1, o139, and non-o1, non-o139 serogroups from both clinical and environmental sources, were examined for the presence of genes encoding cholera toxin (ctxa), zonula occludens toxin (zot), accessory cholera enterotoxin (ace), hemolysin (hlya), nag-specific heat-stable toxin (st), toxin-coregulated pilus (tcpa), and outer membrane protein (ompu), for genomic organization, and for the presence of the regulatory protein genes tcpi a ...	2001	11157262
expression and mutagenesis of the nqrc subunit of the nqr respiratory na(+) pump from vibrio cholerae with covalently attached fmn.	the na(+)-translocating nadh:quinone oxidoreductase (na(+)-nqr) is present in the membranes of a number of marine bacteria and pathogenic bacteria. two of the six subunits of the na(+)-nqr, nqrb and nqrc, have been previously shown to contain covalently bound flavin adenine mononucleotide (fmn). in the current work, the cloning of nqrc from vibrio cholerae is reported. the gene has been expressed in v. cholerae and shown to contain one equivalent of covalently bound fmn. in contrast, no covalent ...	2001	11248234
identification of the cobalamin-dependent methionine synthase gene, meth, in vibrio fischeri atcc 7744 by sequencing using genomic dna as a template.	to confirm the presence of cobalamin-dependent methionine synthase (cdms) in luminous bacteria, which is a prerequisite for the substantiation of our proposals on the physiological function of the lux operon, we identified the cdms gene (meth) in vibrio fischeri atcc 7744. two partial meth sequences, one located near the 5'-terminus of the gene and the other near the 3'-terminus, were sequenced by a pcr based method. to design a new set of pcr primers located on the two flanking regions of the g ...	2001	11250084
non-serogroup o:1 vibrio cholerae bacteremia and cerebritis.	we describe a case of non-serogroup o:1 vibrio cholerae bacteremia and cerebritis in a 41-year-old thai man with alcoholism who presented with fever and cellulitis of the right ankle. he was successfully treated with parenteral cefotaxime and then was switched to treatment with oral ciprofloxacin.	2001	11264049
role of sodium bioenergetics in vibrio cholerae.	the ability of the bacterium to use sodium in bioenergetic processes appears to play a key role in both the environmental and pathogenic phases of vibrio cholerae. aquatic environments, including fresh, brackish, and coastal waters, are an important factor in the transmission of cholera and an autochthonous source. the organism is considered to be halophilic and has a strict requirement for na(+) for growth. furthermore, expression of motility and virulence factors of v. cholerae is intimately l ...	2001	11248198
evidence of calcium influx across the plasma membrane depends upon the initial rise of cytosolic calcium with activation of ip(3) in rat enterocytes by heat-stable enterotoxin of vibrio cholerae non-o1.	in response to heat-stable enterotoxin of vibrio cholerae non-o1, the initial rise of cytosolic ca(2+) occurred with activation of ip(3). chelation of extracellular ca(2+) with egta and suspension of cells in ca(2+) free buffer both demonstrated the involvement of internal stores in the rise of [ca(2+)]i. cells pretreated with dantrolene resulted in decrease of [ca(2+)]i response which suggested that the rise of intracellular level of ca(2+) was mostly due to the mobilization from ip(3) sensitiv ...	2001	11257546
detection of etiological agent for cholera by pcr protocol.	pcr protocol for vibrio cholerae, the causative agent of the diarrheal disease cholera has been described in this report. we report the detection of vibrio species in drinking water samples in a duplex pcr reaction. the target loci used in the study were ctxa and tcpa. the sensitivity and efficiency of detection of this protocol can be applied in epidemic conditions, wherein monitoring of target organisms is very crucial.	2001	11257729
bacteraemia and mortality among adult medical admissions in malawi--predominance of non-typhi salmonellae and streptococcus pneumoniae.	the high seroprevalence of hiv in malawi might be expected to alter the pattern of pathogens isolated from bacteraemic patients. we aimed to describe the frequency and seasonal pattern of bacterial isolates from blood, their antibiotic susceptibility, and patient outcome, in order to provide data on which to base empirical antibiotic therapy and further studies of pathogenesis.	2001	11243753
vibrio parahaemolyticus associated with cholera-like diarrhea among patients in north jakarta, indonesia.	a diarrhea study was conducted in north jakarta, indonesia from december 1996 through december 1997. vibrio parahaemolyticus was isolated from 333 (6.1%) of 5442 rectal swab samples collected from patients with cholera-like diarrhea. vibrio cholerae o1 was isolated from 545 (10.0%) and v. cholerae non-o1 from 183 samples (3.4%), respectively. patients positive for v. parahaemolyticus were mostly adults between 20 and 40 years of age, with males constituting 62%. a majority (65%) of these patient ...	2001	11248518
preparation, immunogenicity, and protective efficacy, in a murine model, of a conjugate vaccine composed of the polysaccharide moiety of the lipopolysaccharide of vibrio cholerae o139 bound to tetanus toxoid.	the epidemic and pandemic potential of vibrio cholerae o139 is such that a vaccine against this newly emerged serogroup of v. cholerae is required. a conjugate made of the polysaccharide moiety (o-specific polysaccharide plus core) of the lipopolysaccharide (lps) of v. cholerae o139 (pmlps) was prepared by derivatization of the pmlps with adipic acid dihydrazide and coupling to tetanus toxoid (tt) by carbodiimide-mediated condensation. the immunologic properties of the conjugate were tested usin ...	2001	11292781
characterization of the plesiomonas shigelloides genes encoding the heme iron utilization system.	plesiomonas shigelloides is a gram-negative pathogen which can utilize heme as an iron source. in previous work, p. shigelloides genes which permitted heme iron utilization in a laboratory strain of escherichia coli were isolated. in the present study, the cloned p. shigelloides sequences were found to encode ten potential heme utilization proteins: huga, the putative heme receptor; tonb and exbbd; hugb, the putative periplasmic binding protein; hugcd, the putative inner membrane permease; and t ...	2001	11292789
the genome of the smartest pathogen decoded: is the cholera war over?		2001	11192451
characterization of cytosolic sialidase from chinese hamster ovary cells: part ii. substrate specificity for gangliosides.	cytosolic chinese hamster ovary (cho) cell sialidase has been cloned as a soluble glutathione s-transferase (gst)-sialidase fusion protein with an apparent molecular weight of 69 kd in escherichia coli. the enzyme has then been produced in mg quantities at 25-l bioreactor scale and purified by one-step affinity chromatography on glutathione sepharose (burg, m.; müthing, j. carbohydr. res. 2001, 330, 335-346). the cloned sialidase was probed for desialylation of a wide spectrum of different types ...	2001	11270813