scholarly journals Analysis of expression of toxin-coregulated pili in classical and El Tor Vibrio cholerae O1 in vitro and in vivo.

1992 ◽  
Vol 60 (10) ◽  
pp. 4278-4284 ◽  
Author(s):  
G Jonson ◽  
J Holmgren ◽  
A M Svennerholm
Keyword(s):  
Vibrio Cholerae ◽  
Vibrio Cholerae O1 ◽  
El Tor

scholarly journals Characterization of Vibrio cholerae O1 El TorgalU and galE Mutants: Influence on Lipopolysaccharide Structure, Colonization, and Biofilm Formation

2001 ◽  
Vol 69 (1) ◽  
pp. 435-445 ◽  
Author(s):  
Jutta Nesper ◽  
Crystal M. Lauriano ◽  
Karl E. Klose ◽  
Dagmar Kapfhammer ◽  
Anita Kraiß ◽  
...  
Keyword(s):  
Organic Acids ◽  
Vibrio Cholerae ◽  
Bile Salts ◽  
Short Chain ◽  
Core Oligosaccharide ◽  
O Antigen ◽  
Mouse Small Intestine ◽  
Vibrio Cholerae O1 ◽  
El Tor

ABSTRACT 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 lipopolysaccharide (LPS). Both gal mutants as well as a rough LPS (R-LPS) mutant were investigated for the ability to colonize the mouse small intestine. The galU and R-LPS mutants, but not thegalE mutant, were defective in colonization, a phenotype also associated with O-antigen-negative mutants. By investigating several parameters in vitro, we could show that galU and R-LPS mutants were more sensitive to short-chain organic acids, cationic antimicrobial peptides, the complement system, and bile salts as well as other hydrophobic agents, indicating that their outer membrane no longer provides an effective barrier function. O-antigen-negative strains were found to be sensitive to complement and cationic peptides, but they displayed significant resistance to bile salts and short-chain organic acids. Furthermore, we found thatgalU and galE are essential for the formation of a biofilm in a spontaneous phage-resistant rugose variant, suggesting that the synthesis of UDP-galactose via UDP-glucose is necessary for biosynthesis of the exopolysaccharide. In addition, we provide evidence that the production of exopolysaccharide limits the access of phage K139 to its receptor, the O antigen. In conclusion, our results indicate involvement of galU in V. cholerae virulence, correlated with the observed change in LPS structure, and a role for galU and galE in environmental survival of V. cholerae.

scholarly journals Second-Generation Recombination-Based In Vivo Expression Technology for Large-Scale Screening for Vibrio cholerae Genes Induced during Infection of the Mouse Small Intestine

2005 ◽  
Vol 73 (2) ◽  
pp. 972-980 ◽  
Author(s):  
C. G. Osorio ◽  
J. A. Crawford ◽  
J. Michalski ◽  
H. Martinez-Wilson ◽  
J. B. Kaper ◽  
...  
Keyword(s):  
Vibrio Cholerae ◽  
Large Scale ◽  
Screening Method ◽  
Mouse Small Intestine ◽  
In Vivo Expression ◽  
Induced Genes ◽  
El Tor ◽  
Selection Of

ABSTRACT We have constructed an improved recombination-based in vivo expression technology (RIVET) and used it as a screening method to identify Vibrio cholerae genes that are transcriptionally induced during infection of infant mice. The improvements include the introduction of modified substrate cassettes for resolvase that can be positively and negatively selected for, allowing selection of resolved strains from intestinal homogenates, and three different tnpR alleles that cover a range of translation initiation efficiencies, allowing identification of infection-induced genes that have low-to-moderate basal levels of transcription during growth in vitro. A transcriptional fusion library of 8,734 isolates of a V. cholerae El Tor strain that remain unresolved when the vibrios are grown in vitro was passed through infant mice, and 40 infection-induced genes were identified. Nine of these genes were inactivated by in-frame deletions, and their roles in growth in vitro and fitness during infection were measured by competition assays. Four mutant strains were attenuated >10-fold in vivo compared with the parental strain, demonstrating that infection-induced genes are enriched in genes essential for virulence.

scholarly journals Expression of Cholera Toxin under Non-AKI Conditions in Vibrio cholerae El Tor Induced by Increasing the Exposed Surface of Cultures

2004 ◽  
Vol 186 (5) ◽  
pp. 1355-1361 ◽  
Author(s):  
Joaquín Sánchez ◽  
Gerardo Medina ◽  
Thomas Buhse ◽  
Jan Holmgren ◽  
Gloria Soberón-Chavez
Keyword(s):  
Cholera Toxin ◽  
Vibrio Cholerae ◽  
Expression Pattern ◽  
Phase 1 ◽  
Inert Atmosphere ◽  
Surface Area Ratio ◽  
Genes Encoding ◽  
El Tor

ABSTRACT The regulatory systems controlling expression of the ctxAB genes encoding cholera toxin (CT) in the classical and El Tor biotypes of pathogenic Vibrio cholerae have been characterized and found to be almost identical. Notwithstanding this, special in vitro conditions, called AKI conditions, are required for El Tor bacteria to produce CT. The AKI conditions involve biphasic cultures. In phase 1 the organism is grown in a still tube for 4 h. In phase 2 the medium is poured into a flask to continue growth with shaking. Virtually no expression of CT occurs if this protocol is not followed. Here we demonstrated that CT expression takes place in single-phase still cultures if the volume-to-surface-area ratio is decreased, both under air and under an inert atmosphere. The expression of key genes involved in the regulation of CT production was analyzed, and we found that the expression pattern closely resembles the in vivo expression pattern.

scholarly journals Expression of virulence factors by classical and El Tor Vibrio cholerae in vivo and in vitro

1990 ◽  
Vol 7 (2-3) ◽  
pp. 221-228 ◽  
Author(s):  
Gunhild Jonson ◽  
Ann-Man Svennerholm ◽  
Jan Holmgren
Keyword(s):  
Vibrio Cholerae ◽  
Virulence Factors ◽  
El Tor

scholarly journals In vitro and in vivo cholera toxin production by classical and El Tor isolates of Vibrio cholerae.

1985 ◽  
Vol 21 (6) ◽  
pp. 884-890 ◽  
Author(s):  
P C Turnbull ◽  
J V Lee ◽  
M D Miliotis ◽  
C S Still ◽  
M Isaäcson ◽  
...  
Keyword(s):  
Cholera Toxin ◽  
Vibrio Cholerae ◽  
Toxin Production ◽  
El Tor

scholarly journals Comparative Analysis of Survival Capacity among Typical and Genovariant Strains of Vibrio cholerae, Biovar El Tor in vivo and in vitro

2015 ◽  
pp. 65-69 ◽  
Author(s):  
S. P. Zadnova ◽  
T. A. Kul’Shan’ ◽  
N. B. Cheldyshova ◽  
A. A. Kritsky ◽  
N. A. Plekhanov ◽  
...  
Keyword(s):  
Comparative Analysis ◽  
Vibrio Cholerae ◽  
Survival Capacity ◽  
El Tor

scholarly journals New Biotype of Vibrio cholerae O1 from Clinical Isolates in Surabaya

2010 ◽  
Vol 1 (1) ◽  
pp. 48
Author(s):  
Garry Cores De Vries ◽  
Emy Koestanti Sabdoningrum ◽  
Dadik Rahardjo
Keyword(s):  
Vibrio Cholerae ◽  
Clinical Isolates ◽  
Epidemic Strain ◽  
Surveillance Strategy ◽  
Pathogenic Variants ◽  
In Vitro Technique ◽  
Vibrio Cholerae O1 ◽  
Arbitrarily Primed Pcr ◽  
El Tor

A surveillance of new pathogenic variants of Vibrio cholerae O1 strains was initiated to identify the emerge and spread throughout Surabaya. Findings from seven years (1994–2000) and from years 2008 until now by using a two-fold surveillance strategy was pursued involving 1) hospital-based case recognition, and 2) environment samples. Rectal swabs and environment samples were transported to ITD-UNAIR, Surabaya for culture and isolates were characterized by serotypic identification and arbitrarily primed PCR fingerprints revealed a group of strains with similar fingerprint patterns that are distinct from those of the current El Tor epidemic strain. These strains have been analyzed by in vitro technique and the group has been denominated the Surabaya-Indonesian variant of V. cholerae O1.

scholarly journals Hemolysin and the Multifunctional Autoprocessing RTX Toxin Are Virulence Factors during Intestinal Infection of Mice with Vibrio cholerae El Tor O1 Strains

2007 ◽  
Vol 75 (10) ◽  
pp. 5035-5042 ◽  
Author(s):  
Verena Olivier ◽  
G. Kenneth Haines ◽  
Yanping Tan ◽  
Karla J. Fullner Satchell
Keyword(s):  
Vibrio Cholerae ◽  
Intestinal Infection ◽  
Lethal Challenge ◽  
Adult Mice ◽  
High Doses ◽  
El Tor ◽  
Vitro Data ◽  
In Vitro Data

ABSTRACT The seventh cholera pandemic that started in 1961 was caused by Vibrio cholerae O1 strains of the El Tor biotype. These strains produce the pore-forming toxin hemolysin, a characteristic used clinically to distinguish classical and El Tor biotypes. Even though extensive in vitro data on the cytolytic activities of hemolysin exist, the connection of hemolysin to virulence in vivo is not well characterized. To study the contribution of hemolysin and other accessory toxins to pathogenesis, we utilized the model of intestinal infection in adult mice sensitive to the actions of accessory toxins. In this study, we showed that 4- to 6-week-old streptomycin-fed C57BL/6 mice were susceptible to intestinal infection with El Tor strains, which caused rapid death at high doses. Hemolysin had the predominant role in lethality, with a secondary contribution by the multifunctional autoprocessing RTX (MARTX) toxin. Cholera toxin and hemagglutinin/protease did not contribute to lethality in this model. Rapid death was not caused by increased dissemination due to a damaged epithelium since the numbers of CFU recovered from spleens and livers 6 h after infection did not differ between mice inoculated with hemolysin-expressing strains and those infected with non-hemolysin-expressing strains. Although accessory toxins were linked to virulence, a strain defective in the production of accessory toxins was still immunogenic since mice immunized with a multitoxin-deficient strain were protected from a subsequent lethal challenge with the wild type. These data suggest that hemolysin and MARTX toxin contribute to vaccine reactogenicity but that the genes for these toxins can be deleted from vaccine strains without affecting vaccine efficacy.

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