scholarly journals Genetic Diversity of the Gene Cluster Encoding Longus, a Type IV Pilus of Enterotoxigenic Escherichia coli

2007 ◽  
Vol 189 (24) ◽  
pp. 9145-9149 ◽  
Author(s):  
Oscar G. Gomez-Duarte ◽  
Sujay Chattopadhyay ◽  
Scott J. Weissman ◽  
Jorge A. Giron ◽  
James B. Kaper ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Gene Cluster ◽  
Protein Level ◽  
Enterotoxigenic Escherichia Coli ◽  
Subunit Gene ◽  
Type Iv Pilus ◽  
Strong Positive Selection ◽  
Type Iv ◽  
Structural Subunit ◽  
Selection For

ABSTRACT Enterotoxigenic Escherichia coli (ETEC) strains produce a type IV pilus named Longus. We identified a 16-gene cluster involved in the biosynthesis of Longus that has 57 to 95% identity at the protein level to CFA/III, another type IV pilus of ETEC. Alleles of the Longus structural subunit gene lngA demonstrate a diversity of 12 to 19% at the protein level with strong positive selection for point replacements and horizontal transfer.

scholarly journals Gene Cluster for Assembly of Pilus Colonization Factor Antigen III of Enterotoxigenic Escherichia coli

2001 ◽  
Vol 69 (9) ◽  
pp. 5864-5873 ◽  
Author(s):  
Tooru Taniguchi ◽  
Yukihiro Akeda ◽  
Ayako Haba ◽  
Yoko Yasuda ◽  
Koichiro Yamamoto ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Nucleotide Sequence ◽  
Gene Cluster ◽  
Enterotoxigenic Escherichia Coli ◽  
Human Colon Carcinoma Cell ◽  
E Coli ◽  
Colonization Factor ◽  
Type Iv ◽  
K 12 ◽  
Factor Antigen

ABSTRACT The assembly of pilus colonization factor antigen III (CFA/III) of enterotoxigenic Escherichia coli (ETEC) requires the processing of CFA/III major pilin (CofA) by a prepilin peptidase (CofP), similar to other type IV pilus formation systems. CofA is produced initially as a 26.5-kDa preform pilin (prepilin) and then processed to a 20.5-kDa mature pilin by CofP which is predicted to be localized in the inner membrane. In the present experiment, we determined the nucleotide sequence of the whole region for CFA/III formation and identified a cluster of 14 genes, includingcofA and cofP. Several proteins encoded bycof genes were similar to previously described proteins, such as the toxin-coregulated pili of Vibrio cholerae and the bundle-forming pili of enteropathogenic E. coli. The G+C content of the cof gene cluster was 37%, which was significantly lower than the average for the E. coli genome (50%). The introduction of a recombinant plasmid containing thecof gene cluster into the E. coli K-12 strain conferred CFA/III biogenesis and the ability of adhesion to the human colon carcinoma cell line Caco-2. This is the first report of a complete nucleotide sequence of the type IV pili found in human ETEC, and our results provide a useful model for studying the molecular mechanism of CFA/III biogenesis and the role of CFA/III in ETEC infection.

scholarly journals Identification of IngA, the structural gene of longus type IV pilus of enterotoxigenic Escherichia coli

Microbiology ◽  
1999 ◽  
Vol 145 (7) ◽  
pp. 1809-1816 ◽  
Author(s):  
Oscar G. Gómez-Duarte ◽  
Alejandro Ruiz-Tagle ◽  
Diana C. Gómez ◽  
Gloria I. Viboud ◽  
Karen G. Jarvis ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Structural Gene ◽  
Enterotoxigenic Escherichia Coli ◽  
Type Iv Pilus ◽  
Type Iv

scholarly journals Identification of Enterotoxigenic Escherichia coli Harboring Longus Type IV Pilus Gene by DNA Amplification

2000 ◽  
Vol 38 (5) ◽  
pp. 1767-1771 ◽  
Author(s):  
Zita Gutiérrez-Cázarez ◽  
Firdausi Qadri ◽  
M. John Albert ◽  
Jorge A. Girón
Keyword(s):  
Escherichia Coli ◽  
Dna Amplification ◽  
Epidemiological Studies ◽  
Enterotoxigenic Escherichia Coli ◽  
Type Iv Pilus ◽  
E Coli ◽  
Colonization Factor ◽  
Type Iv ◽  
Mexican Children ◽  
Enterotoxin Genes

DNA amplification of lngA, the structural gene of longus type IV pilus produced by human enterotoxigenicEscherichia coli (ETEC) was achieved by the use of specific oligonucleotide primers designed from the nucleotide sequence oflngA. A 630-bp fragment representing the entirelngA gene was amplified in eight prototype strains previously characterized as longus positive. Five ETEC strains producing colonization factor antigen III (CFA III) (also a type IV pilus) were also positive by PCR, confirming the DNA homology between CFA III and longus. None of the non-ETEC and non-E. colienteropathogens studied showed the 0.63-kbp amplicon. The procedure thus detected only ETEC strains harboring type IV pili genes with or without other colonization factors. Except for five lngAPCR-positive, probe-positive strains, all lngA PCR-positive strains produced the pilin as demonstrated by immunoblotting. To test the amplification procedure in a clinical setting, a collection of 264 fresh clinical E. coli strains isolated from 88 Mexican children with diarrhea was screened by PCR. Among 82 ETEC isolates found, 30 (36.5%) were lngA PCR-positive. Twenty-seven percent of the children shed ETEC that possessed lngA. In parallel with DNA probes or PCR protocols to detect enterotoxin genes, the lngA PCR method may prove useful for detection of ETEC harboring type IV pilus genes in epidemiological studies.

Phase variation of F1651 (Prs-like) fimbriae from Escherichia coli causing septicaemia in animals

2000 ◽  
Vol 46 (12) ◽  
pp. 1101-1107 ◽  
Author(s):  
Josée Harel ◽  
France Daigle ◽  
Céline Forget ◽  
Marie-Catherine Tessier ◽  
Cécile Crost ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Gene Cluster ◽  
Regulatory Region ◽  
Phase Variation ◽  
Immunofluorescence Staining ◽  
Wild Type ◽  
Young Pigs ◽  
Dam Methylation ◽  
Structural Subunit ◽  
Type Strains

Escherichia coli O115:F165 strains are associated with septicaemia in young pigs and synthesize fimbriae involved in virulence, designated as F1651. F1651 fimbriae belong to the P fimbrial family and are encoded by the foo gene cluster. The foo regulatory region of strain 5131 possesses characteristics similar to that of members of the P regulatory family, including papI and papB homologues, and two GATC sites separated by 102 bp, targets of differential Dam methylation. In wild-type strains, the synthesis of F1651 is repressed by leucine and the fimbriae undergo phase variation. Immunofluorescence staining showed that phase variation of F1651 results in a majority of cells (98%) in the ON phase, in contrast with phase variation of other members of this regulatory family, for which the majority of the cells are in the OFF state. Using a translational fusion in strain 5131 between phoA and fooA, encoding for the major structural subunit of F1651, it was shown that leucine inhibits the OFF to ON switch and modulates the basal transcription of the foo operon.Key words: Escherichia coli, fimbriae, phase variation, regulation, septicaemia.

scholarly journals Construction and Characterization of Bivalent Shigella flexneri 2a Vaccine Strains SC608(pCFAI) and SC608(pCFAI/LTB) That Express Antigens from Enterotoxigenic Escherichia coli

2005 ◽  
Vol 73 (1) ◽  
pp. 258-267 ◽  
Author(s):  
Ryan T. Ranallo ◽  
C. Piyumi Fonseka ◽  
Fred Cassels ◽  
Jay Srinivasan ◽  
Malabi M. Venkatesan
Keyword(s):  
Escherichia Coli ◽  
Vaccine Strain ◽  
Shigella Flexneri ◽  
Immunoblot Analysis ◽  
Enterotoxigenic Escherichia Coli ◽  
Enzyme Linked Immunosorbent Assay ◽  
Live Attenuated Vaccine ◽  
Fimbrial Subunit ◽  
Semialdehyde Dehydrogenase ◽  
Structural Subunit

ABSTRACT An invasive strain of Shigella flexneri 2a (SC608) has been developed as a vector for the expression and delivery of heterologous antigens. SC608 is an aspartate semialdehyde dehydrogenase (asd) derivative of SC602 (icsA iuc), a well-characterized live attenuated vaccine strain which has undergone several clinical trials in human volunteers. When administered orally at a single 104 (CFU) dose, SC602 is both immunogenic and efficacious against shigellosis. Using asd-based plasmid vectors, we designed SC608 to express the enterotoxigenic Escherichia coli (ETEC) fimbrial subunit CfaB (CFA/I structural subunit) alone or in combination with the E. coli B subunit of heat-labile enterotoxin (LTB). The expression of each heterologous protein in SC608 was verified by immunoblot analysis. Each strain was comparable to the parent strain, SC602, in a HeLa cell invasion assay. After intranasal immunizations of guinea pigs, serum and mucosal immune responses were detected against both Shigella lipopolysaccharide and heterologous ETEC antigens by enzyme-linked immunosorbent assay and ELISPOT analysis. All immunized animals were subsequently protected against a challenge with wild-type S. flexneri 2a in a keratoconjunctivitis Sereny test. Serum antibodies generated against LTB and CfaB demonstrated antitoxin and agglutination activities, respectively. These results suggest that CfaB and LTB expressed in SC608 retain important conformational epitopes that are required for the generation of antibodies that have functional activities. These initial experiments demonstrate that a fully invasive Shigella vaccine strain can be engineered to deliver antigens from other diarrheal pathogens.

scholarly journals Deciphering the Conformational Dynamics of Escherichia coli Type IV Pilus

2021 ◽  
Vol 120 (3) ◽  
pp. 294a
Author(s):  
Yasaman Karami ◽  
Olivera Francetic ◽  
Nadia Izadi Pruneyre ◽  
Michael Nilges
Keyword(s):  
Escherichia Coli ◽  
Conformational Dynamics ◽  
Type Iv Pilus ◽  
Type Iv
Sign in / Sign up

Export Citation Format

Share Document