Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| [aeromonas associated with an acute diarrhea outbreak in são bento do una, pernambuco]. | an acute diarrhea outbreak, with 2170 cases, was described during january to july, 2004, in são bento do una, pernambuco. 582 stools were examined and an enteric pathogen was recovered in 25% (145 patients). aeromonas species were the most frequent (114-19.5%) and the main isolates were aeromonas caviae (57-9.8%), aeromonas veronii biovar sobria (23-3.9%), aeromonas veronii biovar veronii (15-2.6%) and other species (19-3.2%). the other isolated enteropathogens were vibrio cholerae o1-ogawa toxi ... | 2006 | 16699653 |
| an outer membrane enzyme encoded by salmonella typhimurium lpxr that removes the 3'-acyloxyacyl moiety of lipid a. | the salmonella and related bacteria modify the structure of the lipid a portion of their lipopolysaccharide in response to environmental stimuli. some lipid a modifications are required for virulence and resistance to cationic antimicrobial peptides. we now demonstrate that membranes of salmonella typhimurium contain a novel hydrolase that removes the 3'-acyloxyacyl residue of lipid a in the presence of 5 mm ca2+. we have identified the gene encoding the s. typhimurium lipid a 3'-o-deacylase, de ... | 2006 | 16704973 |
| length of the linker and the interval between immunizations influences the efficacy of vibrio cholerae o1, ogawa hexasaccharide neoglycoconjugates. | ogawa hexasaccharide neoglycoconjugates induce protective antibodies in mice. similar ogawa conjugates but with a longer linker that connects the carrier to shorter saccharides are immunogenic, but generally ineffective at inducing vibriocidal or protective antibodies. the efficacy of ogawa hexasaccharide neoglycoconjugates of different linker lengths were tested. the majority of mice given immunizations separated by a 14-day gap did not produce vibriocidal or protective antibodies. mice immuniz ... | 2006 | 16706794 |
| isolation and characterization of vcec gain-of-function mutants that can function with the acrab multiple-drug-resistant efflux pump of escherichia coli. | vcec is the outer membrane component of the major facilitator (mf) vceab-vcec multiple-drug-resistant (mdr) efflux pump of vibrio cholerae. tolc is the outer membrane component of the resistance-nodulation-division acrab-tolc efflux pump of escherichia coli. although these proteins share little amino acid sequence identity, their crystal structures can be readily superimposed upon one another. in this study, we have asked if tolc and vcec are interchangeable for the functioning of the acrab and ... | 2006 | 16707668 |
| antimicrobial activities of cinnamon oil and cinnamaldehyde from the chinese medicinal herb cinnamomum cassia blume. | both cinnamomum verum j.s. presl. and cinnamomum cassia blume are collectively called cortex cinnamonmi for their medicinal cinnamon bark. cinnamomum verum is more popular elsewhere in the world, whereas c. cassia is a well known traditional chinese medicine. an analysis of hydro-distilled chinese cinnamon oil and pure cinnamaldehyde by gas chromatography/mass spectrometry revealed that cinnamaldehyde is the major component comprising 85% in the essential oil and the purity of cinnamaldehyde in ... | 2006 | 16710900 |
| psychrophilic superoxide dismutase from pseudoalteromonas haloplanktis: biochemical characterization and identification of a highly reactive cysteine residue. | a psychrophilic superoxide dismutase (sod) has been characterized from the antarctic eubacterium pseudoalteromonas haloplanktis (ph). phsod is a homodimeric iron-containing enzyme and displays a high specific activity, even at low temperature. the enzyme is inhibited by sodium azide and inactivated by hydrogen peroxide; it is also very sensitive to peroxynitrite, a physiological inactivator of the human mitochondrial mn-sod. even though phsod is isolated from a cold-adapted micro-organism, its h ... | 2006 | 16713057 |
| differences in gene expression between the classical and el tor biotypes of vibrio cholerae o1. | differences in whole-genome expression patterns between the classical and el tor biotypes of vibrio cholerae o1 were determined under conditions that induce virulence gene expression in the classical biotype. a total of 524 genes (13.5% of the genome) were found to be differentially expressed in the two biotypes. the expression of genes encoding proteins required for biofilm formation, chemotaxis, and transport of amino acids, peptides, and iron was higher in the el tor biotype. these gene expre ... | 2006 | 16714595 |
| a legionellosis case due to contaminated spa water and confirmed by genomic identification in taiwan. | tracing the source of a legionellosis (lg) case revealed that the legionella pneumophila (lp) strain isolated from patient's sputum shared the same serogroup (sg) and pfge-type with 4 lp strains obtained from a spa center. with a high lp-contamination rate (81.2%, 13/16) in all of its 16 basins, this spa center was also found to have a multi-genotypic distribution among its 13 lp isolates, which can be categorized into 5 pfge-types. despite such a serious contamination in the spa center, which u ... | 2006 | 16714844 |
| endotoxin evaluation of eleven lipopolysaccharides by whole blood assay does not always correlate with limulus amebocyte lysate assay. | more than 90% of all publications on endotoxin were carried out with endotoxins (lipopolysaccharide, lps) from enterobacteriaceae. we compared the immune stimulatory potency of 11 different lpss using human whole blood incubations. while the majority of lpss induced cytokine release equipotently, a 1,000-fold more lps from pseudomonas aeruginosa or vibrio cholerae was still less potent in inducing tnf, il-1 beta, il-10 and ifn-gamma though it potently induced nanogram quantities il-8. all lpss t ... | 2006 | 16719988 |
| dna fingerprinting of vibrio cholerae and aeromonas species by pulsed-field minigel electrophoresis. | dna molecules of vibrio cholerae and aeromonas species were prepared by incubating immobilized cells for 4 and 2 h, respectively, with a nonenzymatic solution that contains chemical reagents only (ndsuplus). this method gave results as reproducible as the enzymatic one that uses proteinase k, and rendered dna molecules suitable for fingerprinting by mini-chef electrophoresis. as rapid dna separations at high electric field are achieved in mini-chef chamber with low heat evolution, dna restrictio ... | 2006 | 16721902 |
| detection and quantification of vibrio populations using denaturant gradient gel electrophoresis. | bacteria affiliated with the genus vibrio are endemic in marine and estuarine ecosystems and are also found in many freshwater environments. vibrios can enter viable but non-culturable states and since many species are pathogenic, there is a great need for culture-independent methods that identify and quantify multiple vibrio populations. we adopted vibrio-specific 16s rrna-directed primers and a competitive pcr protocol (qc-pcr; [thompson, j.r., randa, m.a., marcelino, l.a., tomita-mitchell, a. ... | 2006 | 16730823 |
| immunological properties of complex conjugates based on vibrio cholerae o1 ogawa lipopolysaccharide antigen. | host protection by humoral immunity against vibrio cholerae o1 confers lipopolysaccharide (lps)-specific vibriocidal antibodies. levels of relevant specific antibodies are closely related to complement-mediated inactivation of the vibrios inoculum, especially on the mucosal surface of intestine. we have tested complex v. cholerae o1 ogawa-detoxified lipopolysaccharide (dlps) conjugates. the first conjugate contained glucan both as the immunomodulator and the matrix; the second conjugate containe ... | 2006 | 16734622 |
| [application of pulsed-field gel electrophoresis typing in tracing and carrying out surveillance programs on o139 cholera outbreaks]. | to study the characteristics of molecular typing and phylogenic relationship among the vibrio cholerae serogroup o139 strains isolated from environment and sea food samples during cholera outbreaks, in sichuan province in 2004 and to trace the source of infections so as to support the ascertainment of epidemic control strategy. | 2006 | 16749988 |
| serum igm levels against select marine bacteria in the atlantic sharpnose shark (rhizoprionodon terraenovae) from three estuaries. | the atlantic sharpnose shark (rhizoprionodon terraenovae) is abundant and easily captured throughout the southeastern united states. therefore this species serves as an ideal model for generating basic immunological reagents to establish baseline information regarding the immunophysiology of sharks in the wild, and for attempting to correlate shark immune responses to potential pathogens with the quality of the habitat in which they reside. sharpnose shark serum igm was purified over a protein-a ... | 2006 | 16750427 |
| zentralblatt für bakteriologie - 100 years ago: early considerations of the el tor vibrios. | 2006 | 16750934 | |
| seasonal cholera caused by vibrio cholerae serogroups o1 and o139 in the coastal aquatic environment of bangladesh. | since vibrio cholerae o139 first appeared in 1992, both o1 el tor and o139 have been recognized as the epidemic serogroups, although their geographic distribution, endemicity, and reservoir are not fully understood. to address this lack of information, a study of the epidemiology and ecology of v. cholerae o1 and o139 was carried out in two coastal areas, bakerganj and mathbaria, bangladesh, where cholera occurs seasonally. the results of a biweekly clinical study (january 2004 to may 2005), emp ... | 2006 | 16751520 |
| a vibrio cholerae protease needed for killing of caenorhabditis elegans has a role in protection from natural predator grazing. | vibrio cholerae is the causal bacterium of the diarrheal disease cholera, and its growth and survival are thought to be curtailed by bacteriovorous predators, e.g., ciliates and flagellates. we explored caenorhabditis elegans as a test organism after finding that v. cholerae can cause lethal infection of this nematode. by reverse genetics we identified an extracellular protease, the previously uncharacterized prtv protein, as being necessary for killing. the killing effect is associated with the ... | 2006 | 16754867 |
| synthesis, stereochemistry, and antimicrobial activity of 2,6-diaryl-3-(arylthio)piperidin-4-ones. | a series of novel 2,6-diaryl-3-(arylthio)piperidin-4-ones have been synthesized by reaction of arylthioacetones, substituted aromatic aldehydes, and methylamine/ammonium acetate and their structures elucidated by (1)h, (13)c, and 2d nmr (h, h-cosy, c, h-cosy, hmbc, and noesy) spectroscopy. the nmr data reveal that all these piperidones exist in chair conformation with the 2,6-diaryl groups equatorially oriented, while the arylthio group prefers to be in either an equatorial or axial orientation ... | 2006 | 16755046 |
| [a comparative analysis of molecular-genetic peculiarities of the genomes of cholera, plague and anthrax agents and their evolutional transformations]. | cholera, plague, and anthrax, the diseases that have accounted for millions of human victims, still endanger the entire mankind by possible development of epidemic outbreaks due to their spread or application as bioterrorist agents. generalized results of research into the genomic features of the vibrio cholerae, yersinia pestis, and bacillus anthracis are discussed. despite different frequencies of evolutional transformations occurring in their genomes, that are likely to be associated with div ... | 2006 | 16755997 |
| [antibiotic susceptibility of vibrio cholerae 01: evolution after prolonged curative and preventive use during the 2004 cholera epidemics in douala (cameroon)]. | antibiotics were extensively used, both for curative as for prophylactic purposes, to prevent an explosive spread of the 2004 cholera epidemic in douala. it was thus necessary to control the antibiotic susceptibility of vibrio cholerae. | 2006 | 16757139 |
| atypical cases of cholera due to serogroup o1 in the native population of oman and its relation to non-o1/o139. | 2006 | 16758061 | |
| single-dose azithromycin for the treatment of cholera in adults. | single-dose azithromycin is effective in the treatment of severe cholera in children, but its effectiveness in adults has not been evaluated. | 2006 | 16760445 |
| cholera--still teaching hard lessons. | 2006 | 16760452 | |
| diarrheal epidemics in dhaka, bangladesh, during three consecutive floods: 1988, 1998, and 2004. | we examined demographic, microbiologic, and clinical data from patients presenting during 1988, 1998, and 2004 flood-associated diarrheal epidemics at a diarrhea treatment hospital in dhaka, bangladesh. compared with non-flood periods, individuals presenting during flood-associated epidemics were older, more severely dehydrated, and of lower socioeconomic status. during flood-associated epidemics, vibrio cholerae was the most commonly identified cause of diarrhea, and the only diarrheal pathogen ... | 2006 | 16760521 |
| bacteremia and spontaneous bacterial peritonitis due to vibrio cholerae (non-o1 non-o139) in liver cirrhosis. | 2006 | 16763354 | |
| salinity-induced survival strategy of vibrio cholerae associated with copepods in cochin backwaters. | the occurrence of vibrio cholerae in water, sediment and copepods was studied over a wide range of salinity using conventional and polymerase chain reaction (pcr) techniques in the cochin backwaters. v. cholerae occurred either as culturable or non-culturable form in this tropical estuary. during the pre monsoon period when high salinity prevailed (35.5psu) v. cholerae was associated with copepods only in non-culturable form, but with the onset of monsoon when lower salinity prevailed, copepod-a ... | 2006 | 16764894 |
| detection of a phage genome carrying a zonula occludens like toxin gene (zot) in clinical isolates of stenotrophomonas maltophilia. | during a study of the genetic diversity of stenotrophomonas strains, we found an autonomous replicating dna molecule in chromosomal dna preparations of the clinical stenotrophomonas maltophilia strain c5. the entire sequence of 6,907 bp of the isolated dna molecule was determined, which was called phisma9. seven orfs, which code for proteins with considerable similarity to proteins in databases, were identified in the dna sequence. the largest orf shows high sequence similarities to the pi prote ... | 2006 | 16775751 |
| protein disulfide isomerase-like proteins play opposing roles during retrotranslocation. | misfolded proteins in the endoplasmic reticulum (er) are retained in the organelle or retrotranslocated to the cytosol for proteasomal degradation. er chaperones that guide these opposing processes are largely unknown. we developed a semipermeabilized cell system to study the retrotranslocation of cholera toxin (ct), a toxic agent that crosses the er membrane to reach the cytosol during intoxication. we found that protein disulfide isomerase (pdi) facilitates ct retrotranslocation, whereas erp72 ... | 2006 | 16785320 |
| cholera outbreak in southeast of iran: routes of transmission in the situation of good primary health care services and poor individual hygienic practices. | within the years 2001 to 2004 sistan-va-baluchestan was the only province with transmission of cholera in iran. the objective of this study was to determine the epidemiological characteristics of the cholera outbreak that occurred in 2004 in the sarbaz district in the southern parts of this province. the surveillance data were analyzed, and a matched case-control study was performed. from 22 october to 15 november 2004, from 2,242 diarrhea cases that were sampled for stool culture, 90 cases were ... | 2006 | 16785698 |
| construction and evaluation of a o139 vibrio cholerae vaccine candidate based on a hema gene mutation. | in this paper, we describe the development of vcusm2, a live metabolic auxotroph of vibrio cholerae o139. auxotrophy was achieved by mutating a house keeping gene, hema, that encodes for glutamyl-trna reductase, an important enzyme in the c5 pathway for delta-aminolevulenic acid (ala) biosynthesis, which renders this strain dependent on exogenous ala for survival. experiments using the infant mouse and adult rabbit models show that vcusm2 is a good colonizer of the small intestine and elicits gr ... | 2006 | 16102875 |
| determination of endotoxin by the measurement of the acetylated methyl glycoside derivative of kdo with gas-liquid chromatography-mass spectrometry. | a gas-liquid chromatographic-mass spectrometric (glc-ms) method was applied to the detection of 3-deoxy-d-manno-2-octulosonic acid (kdo), a constituent of bacterial lipopolysaccharide (lps, endotoxin). samples containing lps were dried, methanolyzed with 2 m hcl in methanol at 60 degrees c for 1 h and acetylated with acetic anhydride and pyridine (1:1, v/v) solution at 100 degrees c for 30 min, then the products were analyzed by glc-ms or glc-msms. four acetylated methylglycoside methyl ester de ... | 2006 | 15932775 |
| process development for a cuban cholera vaccine based on the attenuated strain vibrio cholerae 638. | genetically modified vibrio cholerae strain 638 (biotype el tor, serotype ogawa) has previously been shown to be immunogenic in animal models and in human trials. our objective in the work reported herein was to describe the process development methods for the production of the 638 attenuated cholera vaccine. cell seed bank, culture of biomass, lyophilization and final formulation were processes were developed. the results show kinetics of culture that fulfils a logistical model. the microbiolog ... | 2006 | 16085342 |
| multiplex real-time pcr detection of vibrio cholerae. | cholera is an important enteric disease, which is endemic to different regions of the world and has historically been the cause of severe pandemics. vibrio cholerae is a natural inhabitant of the aquatic environment and the toxigenic strains are causative agents of potentially life-threatening diarrhoea. a multiplex, real-time detection assay was developed targeting four genes characteristic of potentially toxigenic strains of v. cholerae, encoding: repeat in toxin (rtxa), extracellular secretor ... | 2006 | 16153727 |
| white shrimp (litopenaeus vannamei) recombinant lysozyme has antibacterial activity against gram negative bacteria: vibrio alginolyticus, vibrio parahemolyticus and vibrio cholerae. | c-type lysozyme has been described as an antibacterial component of the shrimp innate defence system. we determined quantitatively the antibacterial activity of white shrimp (litopenaeus vannamei) recombinant lysozyme against three gram negative bacteria: vibrio alginolyticus, vibrio parahemolyticus and vibrio cholerae, using a turbidimetric assay with live bacteria and differential bacterial viable count after interaction with the protein. in conclusion, the antibacterial activity of recombinan ... | 2006 | 16098764 |
| lipopolysaccharides of vibrio cholerae: iii. biological functions. | this review presents the salient features of the biological functions including the (i) endotoxic activities, (ii) antigenic properties, (iii) immunological responses to and (iv) phage receptor activities of the vibrio cholerae lipopolysaccharides (lps). the biological functions of the capsular polysaccharide (cps) of v. cholerae have also been discussed briefly as a relevant topic. the roles of lps and other extracellular polysaccharides in the (i) intestinal adherence and virulence of the vibr ... | 2006 | 16185850 |
| fluoroquinolone-resistant vibrio cholerae isolated during a cholera outbreak in india. | during the cholera epidemic of 2002 in and around hubli, south india, vibrio cholerae strains resistant to fluoroquinolones were isolated. among the isolates of v. cholerae non-o1, non-o139 serogroups, 55.9% and 47.1% were resistant to norfloxacin and ciprofloxacin, respectively. however, only 12.5% of the o1 serogroup strains were resistant to both norfloxacin and ciprofloxacin. though the o139 serogroup strains were susceptible to these antibiotics, they exhibited multidrug resistance. emergen ... | 2006 | 16246383 |
| chemotaxis between vibrio cholerae o1 and a blue-green alga, anabaena sp. | the chemotactic response of vibrio cholerae o1 towards the mucilaginous sheath of anabaena sp. was investigated by capillary tube method using a virulent strain of v. cholerae o1, el tor, ogawa (3083-t) and its isogenic mutant (hap-1-t) that lacks the hap gene, which codes for mucinase (ha/protease). homogenates of anabaena sp. and purified mucin were used in this study as chemoattractants. results showed 5.7% bacterial accumulation of wild-type v. cholerae o1 towards 4% homogenates of anabaena ... | 2006 | 16207388 |
| incidence of class 1 integrons in multiple antibiotic-resistant gram-negative copiotrophic bacteria from the river torsa in india. | the presence of class 1 integrons in multiple-antibiotic-resistant (mar) gram-negative copiotrophic bacteria from the river torsa in india was detected using a polymerase chain reaction (pcr)-based screening method. among 100 isolates that were resistant to at least five of the twelve antibiotics tested, 40 carried class 1 integrons, with inserted dna regions of 0.7-3.2 kb. carriage of integrons in strains of higher mar index was found to be statistically significant. dna sequencing was used to ... | 2006 | 16239097 |
| modelling, synthesis and biological evaluation of novel glucuronide-based probes of vibrio cholerae sialidase. | the development of sialidase inhibitors is an area of continuing interest due to their potential use as therapeutic agents to combat viral and bacterial infections. herein, we report our studies involving the sialidase from the pathogen vibrio cholerae, through the modelling, synthesis and biological evaluation of mimetics of 5-acetamido-2,6-anhydro-3,5-dideoxy-d-glycero-d-galacto-non-2-enonic acid (neu5ac2en, 1), a naturally occurring sialidase inhibitor. these mimetics are o- and s-glycosides ... | 2006 | 16275104 |
| conserved role of the linker alpha-helix of the bacterial disulfide isomerase dsbc in the avoidance of misoxidation by dsbb. | in the bacterial periplasm the co-existence of a catalyst of disulfide bond formation (dsba) that is maintained in an oxidized state and of a reduced enzyme that catalyzes the rearrangement of mispaired cysteine residues (dsbc) is important for the folding of proteins containing multiple disulfide bonds. the kinetic partitioning of the dsba/dsbb and dsbc/dsbd pathways partly depends on the ability of dsbb to oxidize dsba at rates >1000 times greater than dsbc. we show that the resistance of dsbc ... | 2006 | 16280324 |
| characterization of the ectoine biosynthesis genes of haloalkalotolerant obligate methanotroph "methylomicrobium alcaliphilum 20z". | the genes involved in biosynthesis of the major compatible solute ectoine (1,4,5,6-tetrahydro-2-methylpyrimidine carboxylic acid) in halotolerant obligate methanotroph "methylomicrobium alcaliphilum 20z" were studied. the complete nucleotide sequences of the structural genes encoding l: -aspartokinase (ask), l-2,4-diaminobutyric acid transaminase (ectb), l-2,4-diaminobutyric acid acetyltransferase (ecta), and l-ectoine synthase (ectc) were defined and shown to be transcribed as a single operon e ... | 2006 | 16283251 |
| sialylation regulates peripheral tolerance in cd4+ t cells. | decreased binding by the 6c10 auto-antibody serves as a unique marker for cd4+ t cell unresponsiveness after the induction of t cell tolerance in vbeta8.1 tcr transgenic mice. we further define the nature of the epitope recognized by the 6c10 antibody to be a subset of thy-1 bearing incompletely sialylated n-linked glycans, and furthermore, we demonstrate that tolerant cd4+ t cells have an increased degree of cell-surface sialylation. to test the significance of the altered glycosylation state i ... | 2006 | 16291658 |
| immunosensor for the detection of vibrio cholerae o1 using surface plasmon resonance. | an immunosensor for the detection of vibrio cholerae o1 was developed on the basis of surface plasmon resonance (spr). a protein g layer was fabricated by means of the chemical coupling between the free amine (-nh2) groups of protein g and the activated carboxyl groups present on a self-assembled monolayer (sam) consisting of a mixture of 11-mercaptoundecanoic acid (mua) and hexanethiol (molar ratio of 1:2). a monoclonal antibody, which was confirmed to be specific to v. cholera o1 by the wester ... | 2006 | 16326089 |
| the regulatory roles of cell surface sialylation and n-glycans in human b cell lymphoma cell adhesion to galectin-1. | surface sialylation and glycosylation of tumor cells is known to affect various biological phenomena. in the present study, we analyzed the regulatory roles of cell surface sialylation in cell adhesion to galectin-1 in the human diffuse large b cell lymphoma (dlbcl) cell line, hbl-2, and burkitt's lymphoma cell line, hbl-8. vibrio cholerae neuraminidase treatment enhanced hbl-2 cell adhesion to galectin-1, suggesting that sialic acid inhibits hbl-2 cell adhesion to galectin-1. the data from empl ... | 2006 | 16327992 |
| a molecular model of the vibrio cholerae cytolysin transmembrane pore. | the cytotoxic activity of some of the most pathogenic strains of vibrio cholerae is associated with a cytolysin protein (vcc), which forms oligomeric transmembrane pores and changes the permeability of intestinal cells. we present here a model structure of the transmembrane pore of vcc based on sequence comparison with other pore-forming toxins. vcc is suggested to form a transmembrane beta-barrel pore with a relatively large trans vestibule region. calculations of the electrostatic profile with ... | 2006 | 16330061 |
| antimicrobial potentiality of the thioxanthene flupenthixol through extensive in vitro and in vivo experiments. | the antipsychotic thioxanthene flupenthixol, possessing a trifluoromethyl substituent at position 2, exhibited a distinct antibacterial property against 352 strains of bacteria from 3 gram-positive and 13 gram-negative genera. the minimum inhibitory concentration (mic) of flupenthixol was determined by the national committee for clinical laboratory standards agar dilution method. mics ranged from 10-100 microg/ml in most of the strains, whilst some strains were inhibited at even lower concentrat ... | 2006 | 16316745 |
| hyperinfectivity: a critical element in the ability of v. cholerae to cause epidemics? | cholera is an ancient disease that continues to cause epidemic and pandemic disease despite ongoing efforts to limit its spread. mathematical models provide one means of assessing the utility of various proposed interventions. however, cholera models that have been developed to date have had limitations, suggesting that there are basic elements of cholera transmission that we still do not understand. | 2006 | 16318414 |
| trophic regulation of vibrio cholerae in coastal marine waters. | cholera disease, caused by the bacterium vibrio cholerae, afflicts hundreds of thousands worldwide each year. endemic to aquatic environments, v. cholerae's proliferation and dynamics in marine systems are not well understood. here, we show that under a variety of coastal seawater conditions v. cholerae remained primarily in a free-living state as opposed to attaching to particles. growth rates of free-living v. cholerae (micro: 0.6-2.9 day(-1)) were high (similar to reported values for the bact ... | 2006 | 16343318 |
| resistance of the cholera vaccine candidate iem108 against ctxphi infection. | the cholera toxin (ct) genes ctxab are carried on a lysogenic phage of vibrio cholerae, ctxphi, which can transfer ctxab between toxigenic and nontoxigenic strains of bacteria. this transfer may pose a problem when live oral cholera vaccine is given to people in epidemic areas, because the toxin genes can be reacquired by the vaccine strains. to address this problem, we have constructed a live vaccine candidate, iem108, which carries an el tor-derived rstr gene. this gene encodes a repressor and ... | 2006 | 16343705 |
| bile acids stimulate biofilm formation in vibrio cholerae. | vibrio cholerae is a gram-negative bacterium that causes the acute diarrhoeal disease cholera. after the bacterium is ingested, it passes through the digestive tract, encountering various environmental stresses including the acidic milieu of the stomach and the toxic effects of bile in the duodenum. while these stresses serve as part of a host defence system, v. cholerae has evolved resistance mechanisms that allow it to evade these defences and establish infection. we examined the expression pr ... | 2006 | 16359328 |
| territorial waters of the baltic sea as a source of infections caused by vibrio cholerae non-o1, non-o139: report of 3 hospitalized cases. | a fatal infection with temporal relation to 2 other febrile infections caused by vibrio cholerae non-o1, non-o139 (ncv) occurred in finland in 2003. all infections were associated with contact with seawater. the patient who died had also eaten home-salted whitefish, tested positive for ncv, preceding his symptoms. all patients had compromising factors, and all strains were distinguishable by pulsed-field gel electrophoresis and negative for the ctx gene. these 3 cases illustrate that, despite be ... | 2006 | 16368474 |
| identification of a constitutively active variant of luxo that affects production of ha/protease and biofilm development in a non-o1, non-o139 vibrio cholerae o110. | pathogenesis of vibrio cholerae depends on the concerted action of numerous virulence factors that includes a secreted hemagglutinin (ha) protease. recent studies have evidenced that the expression of these virulence factors as well as the genes responsible for biofilm development is subject to control by quorum sensing in this organism. at low cell density, luxo, the pivotal regulator of quorum-sensing circuit, has been shown to be phosphorylated at aspartate-47. working in concert with sigma-5 ... | 2006 | 16376028 |
| helicobacter pylori-associated chronic atrophic gastritis involving the gastric body and severe disease by vibrio cholerae. | evidence has associated chronic infection by helicobacter pylori with chronic gastritis, low gastric acid production and an increased risk of life-threatening cholera. however, the relationship of specific patterns of histological damage in the gastric mucosa associated with h. pylori infection and the occurrence of cholera has not been described. the purpose of this study was to compare the gastric ph and histopathological findings in gastric biopsies taken from patients with severe diarrhoeal ... | 2006 | 16376396 |
| recent progress in vaccines for amebiasis. | the persistence of amebiasis as a global health problem, despite the availability of effective treatment, has led to the search for vaccines to prevent this deadly disease. recent clinical studies suggest that mucosal immunity could provide some protection against recurrent intestinal infection with e. histolytica, but there is contradictory evidence about protective immunity after amebic liver abscess. progress in vaccine development has been facilitated by new animal models that allow better t ... | 2006 | 16380333 |
| autorepression of rctb, an initiator of vibrio cholerae chromosome ii replication. | the rctb protein binds to the origin of replication of vibrio cholerae chromosome ii (chrii) and is required for oriciivc-based replication. here, we found that rctb acts as an autorepressor, inhibiting rctb transcription. integration host factor promotes rctb transcription, while dam and dnaa, factors required for replication of both v. cholerae chromosomes, influence rctb autorepression. thus, rctb appears to regulate chrii replication as both an initiator and a transcription repressor, and it ... | 2006 | 16385068 |
| a vibrio cholerae relaxed (rela) mutant expresses major virulence factors, exhibits biofilm formation and motility, and colonizes the suckling mouse intestine. | we have constructed a relaxed mutant of el tor biotype vibrio cholerae strain c7258 by disruption of the rela catalytic domain. the ability of the v. cholerae relaxed mutant to biosynthesize guanosine tetraphosphate and pentaphosphate was severely affected; the mutant showed a reduced growth rate in minimal medium that could be reversed by the addition of casamino acids, and it was thermosensitive. contrary to published findings, the new rela mutant still produced significant cholera toxin and t ... | 2006 | 16385069 |
| slyd proteins from different species exhibit high prolyl isomerase and chaperone activities. | slyd is a putative folding helper protein from the escherichia coli cytosol, which consists of an n-terminal prolyl isomerase domain of the fkbp type and a presumably unstructured c-terminal tail. we produced truncated versions without this tail (slyd) for slyd from e. coli, as well as for the slyd orthologues from yersinia pestis, treponema pallidum, pasteurella multocida, and vibrio cholerae. they are monomeric in solution and unfold reversibly. all slyd variants catalyze the proline-limited r ... | 2006 | 16388577 |
| antidiarrhoeal evaluation of aegle marmelos (correa) linn. root extract. | a study was undertaken to evaluate the in vitro and in vivo antidiarrhoeal potential of chloroform extract of the root of aegle marmelos (correa) linn. the in vitro activity was determined by agar dilution and disc diffusion techniques. the extract was studied in vivo in rats. of the 35 tested pathogenic diarrhoea causing strains, the extract was found to be mostly active against the strains of vibrio cholerae, followed by escherichia coli and shigella spp. the in vitro activity was found to be ... | 2006 | 16397850 |
| evaluation of three rapid diagnostic tests for cholera: does the skill level of the technician matter? | to evaluate smart, medicos dip stick and an institut pasteur (ip) cholera dipstick tests for accuracy and ease of use. | 2006 | 16398755 |
| comparison of methods for recovering vibrio cholerae o1 from ice. | alkaline peptone water (1% peptone, 1% nacl, ph 8.5) and trypticase soy yeast extract broth (tsyb) supplemented with 2.5% nacl (ph 8.5) or 1% nacl (ph 7.5) were evaluated as enrichment broths for the isolation of vibrio cholerae o1 from ice. thirty samples of sterile and nonsterile mineral water were inoculated with cell suspensions of this bacterium, quickly frozen, and stored for 3 days at--18 degrees c. after thawing, samples were analyzed by a three-tube most-probable-number technique. incub ... | 2006 | 16416923 |
| dependent population dynamics between chironomids (nonbiting midges) and vibrio cholerae. | vibrio cholerae, the causative agent of cholera, is a natural inhabitant of the aquatic ecosystem. chironomid (nonbiting midges) egg masses were recently found to harbour v. cholerae non-o1 and non-o139, providing a natural reservoir for the cholera bacterium. chironomid populations and the presence of v. cholerae in chironomid egg masses were monitored. all v. cholerae isolates were able to degrade chironomid egg masses. the following virulence associated genes were detected in the bacterial is ... | 2006 | 16420618 |
| disarming pathogens--a new approach for antibiotic development. | 2006 | 16421373 | |
| two cases of toxigenic vibrio cholerae o1 infection after hurricanes katrina and rita--louisiana, october 2005. | louisiana was struck by hurricane katrina on august 29, 2005, and by hurricane rita on september 24, 2005. the two hurricanes caused unprecedented damage from wind and storm surge to the louisiana gulf coast region, and levee breaks resulted in flooding of large residential areas in and around new orleans. with the flooding, an immediate public health concern was the potential for outbreaks of infectious diseases, including cholera. nearly all vibrio infections in the united states are caused by ... | 2006 | 16424854 |
| o1 and non-o1 vibrio cholerae bacteremia produced by hemolytic strains. | vibrio cholerae are gram-negative bacteria capable of producing serious infections. they are differentiated into o1 and non-o1 serogroups, depending on their ability to agglutinate with specific antiserum. in contrast to non-o1 v. cholerae, which are more prone to invading the bloodstream, v. cholerae o1 is rarely the cause of bacteremia. we describe 2 cases of o and non-o1 v. cholerae bacteremia in patients with hepatitis c virus cirrhosis. we postulate that the hemolytic properties of the isol ... | 2006 | 16426794 |
| identification and characterization of rbma, a novel protein required for the development of rugose colony morphology and biofilm structure in vibrio cholerae. | phase variation between smooth and rugose colony variants of vibrio cholerae is predicted to be important for the pathogen's survival in its natural aquatic ecosystems. the rugose variant forms corrugated colonies, exhibits increased levels of resistance to osmotic, acid, and oxidative stresses, and has an enhanced capacity to form biofilms. many of these phenotypes are mediated in part by increased production of an exopolysaccharide termed vps. in this study, we compared total protein profiles ... | 2006 | 16428409 |
| segregation of the replication terminus of the two vibrio cholerae chromosomes. | genome duplication and segregation normally are completed before cell division in all organisms. the temporal relation of duplication and segregation, however, can vary in bacteria. chromosomal regions can segregate towards opposite poles as they are replicated or can stay cohered for a considerable period before segregation. the bacterium vibrio cholerae has two differently sized circular chromosomes, chromosome i (chri) and chrii, of about 3 and 1 mbp, respectively. the two chromosomes initiat ... | 2006 | 16428410 |
| activation of the vibrio cholerae sos response is not required for intestinal cholera toxin production or colonization. | cholera toxin, one of the main virulence factors of vibrio cholerae, is encoded in the genome of ctxphi, a v. cholerae-specific lysogenic filamentous bacteriophage. although the genes encoding cholera toxin, ctxab, are known to have their own promoter, the toxin genes can also be transcribed from an upstream ctxphi promoter, prsta. the v. cholerae sos response to dna damage induces the ctx prophage by stimulating gene expression initiating from prsta. here, we investigated whether ctxa mrna leve ... | 2006 | 16428736 |
| genetic and phenotypic diversity of quorum-sensing systems in clinical and environmental isolates of vibrio cholerae. | vibrio cholerae is the causative agent of cholera, a severe and devastating diarrheal disease. v. cholerae lives naturally in various aquatic habitats during interepidemic periods. recent studies reveal that quorum-sensing systems, which exist in many bacteria and help them monitor their population densities and regulate various cellular functions, control v. cholerae pathogenesis, biofilm formation, and protease production. in this study we surveyed quorum-sensing systems in 16 geographically d ... | 2006 | 16428762 |
| identification of a conserved bacterial protein secretion system in vibrio cholerae using the dictyostelium host model system. | the bacterium vibrio cholerae, like other human pathogens that reside in environmental reservoirs, survives predation by unicellular eukaryotes. strains of the o1 and o139 serogroups cause cholera, whereas non-o1/non-o139 strains cause human infections through poorly defined mechanisms. using dictyostelium discoideum as a model host, we have identified a virulence mechanism in a non-o1/non-o139 v. cholerae strain that involves extracellular translocation of proteins that lack n-terminal hydropho ... | 2006 | 16432199 |
| multilocus sequence typing (mlst) analysis of vibrio cholerae o1 el tor isolates from mozambique that harbour the classical ctx prophage. | vibrio cholerae o1 isolates belonging to the ogawa serotype, el tor biotype, harbouring the classical ctx prophage were first isolated in mozambique in 2004. multilocus sequence typing (mlst) analysis using nine genetic loci showed that the mozambique isolates have the same sequence type (st) as o1 el tor n16961, a representative of the current seventh cholera pandemic. analysis of the ctx prophage in the mozambique isolates indicated that there is one type of rstr in these isolates: the classic ... | 2006 | 16434708 |
| trends in cholera epidemiology. | 2006 | 16435891 | |
| consecutive outbreaks of vibrio cholerae o139 and v. cholerae o1 cholera in a fishing village near karachi, pakistan. | in july 2002 and june 2003, cholera outbreaks were detected by a diarrhoea surveillance system in a village outside karachi, pakistan. specimens were culture confirmed. the first outbreak was caused by vibrio cholerae o139 (n = 30) and the second outbreak by v. cholerae o1 (n = 39). demographic and clinical features of patients were recorded and case-control studies were conducted following each outbreak. clinical information was obtained for 29 of the 30 patients in the first outbreak, and 2 of ... | 2006 | 16443247 |
| the phosphate-starvation response in vibrio cholerae o1 and phob mutant under proteomic analysis: disclosing functions involved in adaptation, survival and virulence. | a proteomic analysis of a wild-type and of a phob mutant showed that vibrio cholerae expresses genes of two major regulons in response to phosphate starvation. the pho regulon, expressed by the wild-type, allowed the cells to adapt to the new environment. induction of the general stress regulon was mainly observed in the phob mutant as a strategy to resist stress and survive. some functions of the adaptative and survival responses play roles in the pathogenicity of the bacteria. among the member ... | 2006 | 16447160 |
| field evaluation of a rapid immunochromatographic dipstick test for the diagnosis of cholera in a high-risk population. | early detection of cholera outbreaks is crucial for the implementation of the most appropriate control strategies. | 2006 | 16451731 |
| etiology and epidemiology of diarrhea in children in hanoi, vietnam. | this paper provides a preliminary picture of diarrhea with regards to etiology, clinical symptoms, and some related epidemiologic factors in children less than five years of age living in hanoi, vietnam. | 2006 | 16458564 |
| formulation in tablets of a cholera whole cells inactivated vaccine candidate. | licensed as well as candidate cholera vaccines available at the present requires the dose preparation (included buffer) at the moment of application. the aim of this work was to evaluate the presentation in oral tablets of an inactivated cholera vaccine to avoid that inconveniences during application. we have therefore compared inactivated cultures of vibrio cholerae with tablets formulation vaccine. we obtained that antigenic activity (elisa) and immunogenicity in animal model (elisa and vibrio ... | 2006 | 16460846 |
| cyclic amp-dependent functional forms of cyclic amp receptor protein from vibrio cholerae. | the cyclic amp receptor protein (crp) from escherichia coli, involved in the transcriptional regulation of a number of genes and operons, works by binding to specific sites upstream of promoters. crp also binds cyclic amp (camp), and this binding, which causes conformational changes in crp, is mandatory for its activity. a camp-dependent variation in the conformation as well as biological activity of e. coli crp has been reported, with the camp-crp complex formed at high camp concentrations rese ... | 2006 | 16464435 |
| antiviral activities of purified compounds from youngia japonica (l.) dc (asteraceae, compositae). | the ethanol extract of a biannual medicinal herb, youngia japonica (commonly known as oriental hawk's beard) was reported previously to have potent antiviral activity against respiratory syncytial virus (rsv) cultured in hep-2 cells. three anti-microbial agents, namely 3,4-dicaffeoylquinic acid, 3,5-dicaffeoylquinic acid, and luteolin-7-o-glucoside were subsequently purified and chemically characterized from the ethanol extract of youngia japonica. the two dicaffeoylquinic acids exhibited promin ... | 2006 | 16469463 |
| [a boy with cholera from india]. | a 7-year-old indian boy travelling from india to the united kingdom was brought to the emergency clinic of airport medical services at schiphol airport in amsterdam, the netherlands. he had had watery diarrhoea in the aircraft and had lost consciousness. in view of the strong indications for cholera and the rice water-like diarrhoea, he was admitted to the paediatric ward of the vu medical centre where intravenous rehydration was carried out. he recovered within three days. a large number of com ... | 2006 | 16471238 |
| crystallization of the nadh-oxidizing domain of the na+-translocating nadh:ubiquinone oxidoreductase from vibrio cholerae. | the na+-translocating nadh:quinone oxidoreductase (na+-nqr) from pathogenic and marine bacteria is a respiratory complex that couples the exergonic oxidation of nadh by quinone to the transport of na+ across the membrane. the nqrf subunit oxidizes nadh and transfers the electrons to other redox cofactors in the enzyme. the fad-containing domain of nqrf has been expressed, purified and crystallized. the purified nqrf fad domain exhibited high rates of nadh oxidation and contained stoichiometric a ... | 2006 | 16511277 |
| cyclo(phe-pro) modulates the expression of ompu in vibrio spp. | vibrio vulnificus was found to produce a chemical that induced the expression of vibrio fischeri lux genes. electron spray ionization-mass spectrometry and 1h nuclear magnetic resonance analyses indicated that the compound was cyclo(l-phe-l-pro) (cfp). the compound was produced at a maximal level when cell cultures reached the onset of stationary phase. sodium dodecyl sulfate-polyacrylamide gel analysis of the total proteins of v. vulnificus indicated that expression of ompu was enhanced by exog ... | 2006 | 16513751 |
| recognition of enolase in the escherichia coli rna degradosome. | in escherichia coli, the glycolytic enzyme enolase is a component of the rna degradosome, which is an rnase e mediated assembly involved in rna processing and transcript turnover. the recruitment of enolase by the rna degradosome has been implicated in the turnover of certain transcripts, and it is mediated by a small segment of roughly a dozen residues that lie within a natively unstructured sub-domain of rnase e. here, we present the crystal structure of enolase in complex with its recognition ... | 2006 | 16516921 |
| tight junction modulation and its relationship to drug delivery. | in order for therapeutic agents to exert their pharmacological effects, they have to cross the biological membranes into the systemic circulation and reach the site of action. drugs cross the membranes by one of two pathways; paracellular or transcellular. most drugs are transported transcellularly depending on their physiocochemical properties, however the paracellular route is usually the main route of absorption for hydrophilic drugs (proteins, peptides, etc.). the paracellular pathway is gov ... | 2006 | 16517003 |
| effect of transport at ambient temperature on detection and isolation of vibrio cholerae from environmental samples. | it has long been assumed that prolonged holding of environmental samples at the ambient air temperature prior to bacteriological analysis is detrimental to isolation and detection of vibrio cholerae, the causative agent of pandemic cholera. the present study was aimed at understanding the effect of transporting environmental samples at the ambient air temperature on isolation and enumeration of v. cholerae. for water and plankton samples held at ambient temperatures ranging from 31 degrees c to ... | 2006 | 16517670 |
| an improved technique for isolation of environmental vibrio cholerae with epidemic potential: monitoring the emergence of a multiple-antibiotic-resistant epidemic strain in bangladesh. | predicting cholera epidemics through monitoring the environment for the presence of pathogenic vibrio cholerae is complicated by the presence in water of a large number of mostly nonpathogenic v. cholerae strains. v. cholerae strains causing recent cholera epidemics in bangladesh carry the sulfamethoxazole-trimethoprim (sxt) element, which encodes resistance to several antibiotics. here, we show that the use of a culture medium containing streptomycin, sulfamethoxazole, and trimethoprim (the ant ... | 2006 | 16518766 |
| thermodynamic properties of the redox centers of na(+)-translocating nadh:quinone oxidoreductase. | redox titration of all optically detectable prosthetic groups of na(+)-translocating nadh:quinone oxidoreductase (na(+)-nqr) at ph 7.5 showed that the functionally active enzyme possesses only three titratable flavin cofactors, one noncovalently bound fad and two covalently bound fmn residues. all three flavins undergo different redox transitions during the function of the enzyme. the noncovalently bound fad works as a "classical" two-electron carrier with a midpoint potential (e(m)) of -200 mv. ... | 2006 | 16519537 |
| proteome analysis of sorbitol fermentation specific protein in vibrio cholerae by 2-de and ms. | vibrio cholerae can be differentiated into epidemic and non-epidemic strains by sorbitol fermentation speed, but little research has been done on its mechanisms. in this study, we investigated differential protein expression of the two strains in response to sorbitol metabolism. v. cholerae strains were cultured in media with and without sorbitol, respectively. proteins were separated by 2-de, and those that showed different expression in the two media were identified by maldi-tof ms. fifteen pr ... | 2006 | 16525996 |
| [vibrio cholerae 01 in a fish aquarium]. | vibrio cholerae 01 was detected from aquarium water and fish imported from thailand and sri lanka. the infected fish were treated with antibiotics and the tanks and other aquatics were decontaminated. none of the persons taking care of the infected fish became ill; bacteriological analyses of fecal specimens of these persons were negative. the significance of the finding is discussed in view of possible transmission and incidence of cholera among aquarists in countries outside cholera endemic ar ... | 2006 | 16528897 |
| the escherichia coli bara-uvry two-component system is a virulence determinant in the urinary tract. | the salmonella enterica bara-sira, the erwinia carotovora exps-expa, the vibrio cholerae bara-vara and the pseudomonas spp gacs-gaca all belong to the same orthologous family of two-component systems as the escherichia coli bara-uvry. in the first four species it has been demonstrated that disruption of this two-component system leads to a clear reduction in virulence of the bacteria. our aim was to determine if the escherichia coli bara-uvry two-component system is connected with virulence usin ... | 2006 | 16529647 |
| spectroscopic and structural impact of a stem base-pair change in dna hairpins: gttc-aca-gaac versus gtac-aca-gtac. | successive investigations over the last decade have revealed and confirmed a stable loop closure in a family of d-[gtac-5pur6n7n-gtac] hairpins, where 5pur6n7n is a aaa, gag and axc loop (x being any nucleotide). the trinucleotide loop is characterized by a well defined 5pur-7n mispairing mode, and by upfield chemical shifts for three sugar protons of the apical nucleotide 6n. the gttc-aca-gaac dna hairpin, of interest for its likely involvement in vibrio cholerae genome mutations, has now been ... | 2006 | 16530466 |
| the current ice age: biology and evolution of sxt-related integrating conjugative elements. | sxt is an integrating conjugative element (ice) that was initially isolated from a 1992 vibrio cholerae o139 clinical isolate from india. this approximately 100-kb ice encodes resistance to multiple antibiotics. sxt or closely related ices are now present in most clinical and some environmental v. cholerae isolates from asia and africa. sxt-related ices are not limited to v. cholerae. it is now clear that so-called incj elements such as r391 are closely related to sxt. more than 25 members of th ... | 2006 | 16530834 |
| negative electrospray, ion trap multistage mass spectrometry of synthetic fragments of the o-ps of vibrio cholerae o:1. | saccharides (mono through hexasaccharides) that mimic the terminal epitopes of o-antigens of vibrio cholerae o:1, serotypes ogawa and inaba, were studied by electrospray ion trap (esi it) mass spectrometry (ms) in the negative mode. anionized adducts are the characteristic ions formed by the capture of h(3)o(2)(-) under the condition of esi ms analysis. the reactive species are produced by reaction of hydroxyl anions with the molecule of water. thus the [m + h(3)o(2)](-) have the highest m/z val ... | 2006 | 16531650 |
| [development of antilipase immunoglobulin polymer diagnosticum for the detection of vibrio cholerae eltor, possessing hemolytic and lipase activity]. | the possibility of using a heterogeneous, but structurally similar antigen--the commercial preparation of pseudomonas sp. lipase (sigma, usa)--for the development of polymer diagnosticum aimed at determination of lipase production in cholera vibrios was shown. the new diagnosticum (antilipase antibodies) on a polymer carrier was used in the serological volume agglomeration test for the detection of hemolytic atoxigenic v. eltor, obtained from environmental, objects, which produced lipase in 80% ... | 2006 | 16532643 |
| modeling the role of bacteriophage in the control of cholera outbreaks. | cholera is a waterborne diarrheal disease that continues to plague the developing world. individuals become infected by consuming water from reservoirs contaminated by virulent strains of the bacterium vibrio cholerae. epidemiological and environmental observations of a cholera outbreak in dhaka, bangladesh, suggest that lytic bacteriophage specific for v. cholerae may limit the severity of cholera outbreaks by killing bacteria present in the reservoir and in infected individuals. to quantify th ... | 2006 | 16537404 |
| histopathological changes in experimental cholera with a non toxigenic non- o1 non-o139 vibrio cholerae strain isolated from kolkata, india. | this study was conducted to understand the pathophysiological changes in experimental rabbit ileal loop model using the vibrio cholerae strain non-o1non-o139, isolated as sole pathogen from clinically diagnosed cholera patients in kolkata. significant amount of haemorrhagic fluid accumulation was observed in all the test loops of rabbit model where the strain of v.cholerae was inoculated as compared to control loops. microscopic examination of the accumulated fluid showed the presence of erythro ... | 2006 | 16538861 |
| vibrio cholerae ctxphi phage repressor gene is borne on an insertion sequence-like element and encodes a putative transposase. | bioinformatics analyses show the presence of a novel insertion sequence-like element in the ctxphi phage of vibrio cholerae. the solitary open reading frame encompassed by the element is known to encode a repressor (rstr) of phage dna replication and is responsible for phage heteroimmunity. analysis of the nucleotide and protein sequence of the repressor and its flanking non-coding regions indicates that it resembles distinctly simple bacterial insertion elements in numerous aspects. based on th ... | 2006 | 16539534 |
| score-based prediction of genomic islands in prokaryotic genomes using hidden markov models. | horizontal gene transfer (hgt) is considered a strong evolutionary force shaping the content of microbial genomes in a substantial manner. it is the difference in speed enabling the rapid adaptation to changing environmental demands that distinguishes hgt from gene genesis, duplications or mutations. for a precise characterization, algorithms are needed that identify transfer events with high reliability. frequently, the transferred pieces of dna have a considerable length, comprise several gene ... | 2006 | 16542435 |
| the transcriptional regulator vqma increases expression of the quorum-sensing activator hapr in vibrio cholerae. | vibrio cholerae is the causative agent of the severe diarrheal disease cholera. a number of environmental stimuli regulate virulence gene expression in v. cholerae, including quorum-sensing signals. at high cell densities, quorum sensing in v. cholerae invokes a series of signal transduction pathways in order to activate the expression of the master regulator hapr, which then represses the virulence regulon and biofilm-related genes and activates protease production. in this study, we identified ... | 2006 | 16547031 |
| altering the length of the lipopolysaccharide o antigen has an impact on the interaction of salmonella enterica serovar typhimurium with macrophages and complement. | a panel of isogenic salmonella enterica serovar typhimurium strains that vary only in the length of the o antigen was constructed through complementation of a wzz double mutant (displaying unregulated o-antigen length) with one of two homologous (wzzst and wzzfepe) or three heterologous (wzzo139 of vibrio cholerae and wzzsf and wzzphs-2 of shigella flexneri) wzz genes. each gene was functional in the s. enterica serovar typhimurium host and specified production of o-antigen polymers with lengths ... | 2006 | 16547065 |
| purification, characterization and comparison of reptile lysozymes. | cation exchange column chromatography and gel filtration chromatography were used to purify four reptile lysozymes from egg white: sstl a and sstl b from soft shelled turtle (trionyx sinensis), astl from asiatic soft shelled turtle (amyda cartilagenea) and gstl from green sea turtle (chelonia mydas). the molecular masses of the purified reptile lysozymes were estimated to be 14 kda by sds-page. enzyme activity of the four lysozymes could be confirmed by gel zymograms and showed charge difference ... | 2006 | 16549391 |