scholarly journals Linkage of the Horizontally Acquired ypm and pil Genes in Yersinia pseudotuberculosis

2005 ◽  
Vol 73 (4) ◽  
pp. 2556-2558 ◽  
Author(s):  
François Collyn ◽  
Hiroshi Fukushima ◽  
Christophe Carnoy ◽  
Michel Simonet ◽  
Pascal Vincent

ABSTRACT The superantigen-encoding ypm gene and the pil gene cluster governing type IV pilus biogenesis have been laterally acquired by Yersinia pseudotuberculosis. PCR assays on 270 unrelated strains from various environmental and animal sources revealed a significant association of ypm and pil in isolates.

2002 ◽  
Vol 70 (11) ◽  
pp. 6196-6205 ◽  
Author(s):  
François Collyn ◽  
Marie-Annick Léty ◽  
Shamila Nair ◽  
Vincent Escuyer ◽  
Amena Ben Younes ◽  
...  

ABSTRACT Fimbriae have been shown to play an essential role in the adhesion of pathogenic gram-negative bacteria to host cells. In the enteroinvasive bacterium Yersinia pseudotuberculosis, we characterized a previously unknown 11-kb chromosomal locus involved in the synthesis of type IV pili. The locus consists of 11 open reading frames forming a polycistronic unit and encoding putative Pil proteins, PilLMNOPQRSUVW. When introduced into Escherichia coli, the Y. pseudotuberculosis operon reconstituted bundles of filaments at a pole on the bacterial surface, demonstrating that the pil locus was functional in a heterogenous genetic background. Environmental factors regulated transcription of the Y. pseudotuberculosis operon; in particular, temperature, osmolarity, and oxygen tension were critical cues. Deletion of the type IV pilus gene cluster was associated with a reduction of Y. pseudotuberculosis pathogenicity for mice infected orally. Forty-one percent of Y. pseudotuberculosis strains isolated from human or animal sources harbored the type IV pilus locus. Therefore, the pil locus of Y. pseudotuberculosis might constitute an “adaptation island,” permitting the microorganism to colonize a vast reservoir.


2003 ◽  
Vol 52 (4) ◽  
pp. 283-288 ◽  
Author(s):  
Tomoko Miyazato ◽  
Claudia Toma ◽  
Noboru Nakasone ◽  
Koichiro Yamamoto ◽  
Masaaki Iwanaga

The nucleotide sequence of an ORF (vcfQ) within the type IV pilus gene cluster of Vibrio cholerae O34 strain NAGV14 was determined, thereby completing the sequence analysis of the structural operon. The vcfQ gene showed homology to the mshQ gene of the mannose-sensitive haemagglutinin pilus gene cluster. The vcfQ was 651 bp larger than mshQ, and the G+C content of the extra 651 bp portion (35.6 mol%) was lower than that of the overall vcfQ gene (42.5 mol%). Except for the first 270 aa residues, the deduced amino acid sequence of VcfQ showed high homology to the MshQ protein. There was immunological cross-reaction between VcfQ and MshQ by Western blotting. Cell fractionation studies showed that VcfQ is located in both the inner and the outer membranes. Mutational analysis showed that vcfQ-deficient mutant expressed detectable levels of major pilin (VcfA), but failed to assemble them into pili, indicating that VcfQ is essential for pilus assembly. Colony-blotting analyses showed that the N-terminal region of vcfQ is variable in V. cholerae strains.


Microbiology ◽  
2021 ◽  
Vol 167 (9) ◽  
Author(s):  
Marie Zachary ◽  
Susanne Bauer ◽  
Maximilian Klepsch ◽  
Katharina Wagler ◽  
Bruno Hüttel ◽  
...  

Non-coding regulatory RNAs mediate post-transcriptional gene expression control by a variety of mechanisms relying mostly on base-pairing interactions with a target mRNA. Though a plethora of putative non-coding regulatory RNAs have been identified by global transcriptome analysis, knowledge about riboregulation in the pathogenic Neisseriae is still limited. Here we report the initial characterization of a pair of sRNAs of N. gonorrhoeae , TfpR1 and TfpR2, which exhibit a similar secondary structure and identical single-stranded seed regions, and therefore might be considered as sibling sRNAs. By combination of in silico target prediction and sRNA pulse expression followed by differential RNA sequencing we identified target genes of TfpR1 which are involved in type IV pilus biogenesis and DNA damage repair. We provide evidence that members of the TfpR1 regulon can also be targeted by the sibling TfpR2.


2007 ◽  
Vol 189 (17) ◽  
pp. 6389-6396 ◽  
Author(s):  
Richard F. Collins ◽  
Muhammad Saleem ◽  
Jeremy P. Derrick

ABSTRACT Type IV pili are surface-exposed retractable fibers which play a key role in the pathogenesis of Neisseria meningitidis and other gram-negative pathogens. PilG is an integral inner membrane protein and a component of the type IV pilus biogenesis system. It is related by sequence to the extensive GspF family of secretory proteins, which are involved in type II secretion processes. PilG was overexpressed and purified from Escherichia coli membranes by detergent extraction and metal ion affinity chromatography. Analysis of the purified protein by perfluoro-octanoic acid polyacrylamide gel electrophoresis showed that PilG formed dimers and tetramers. A three-dimensional (3-D) electron microscopy structure of the PilG multimer was determined using single-particle averaging applied to samples visualized by negative staining. Symmetry analysis of the unsymmetrized 3-D volume provided further evidence that the PilG multimer is a tetramer. The reconstruction also revealed an asymmetric bilobed structure approximately 125 Å in length and 80 Å in width. The larger lobe within the structure was identified as the N terminus by location of Ni-nitrilotriacetic acid nanogold particles to the N-terminal polyhistidine tag. We propose that the smaller lobe corresponds to the periplasmic domain of the protein, with the narrower “waist” region being the transmembrane section. This constitutes the first report of a 3-D structure of a member of the GspF family and suggests a physical basis for the role of the protein in linking cytoplasmic and periplasmic protein components of the type II secretion and type IV pilus biogenesis systems.


2010 ◽  
Vol 78 (9) ◽  
pp. 2049-2057 ◽  
Author(s):  
Vijaykumar Karuppiah ◽  
Darin Hassan ◽  
Muhammad Saleem ◽  
Jeremy P. Derrick

1998 ◽  
Vol 11 (11) ◽  
pp. 1048-1056 ◽  
Author(s):  
Elina Roine ◽  
Deanna M. Raineri ◽  
Martin Romantschuk ◽  
Mark Wilson ◽  
David N. Nunn

Many strains of Pseudomonas syringae produce retractile pili that act as receptors for lytic bacteriophage φ6. As these are also characteristics of type IV pili, it was postulated that P. syringae may possess genes for type IV pilus biogenesis. A cosmid clone bank of P. syringae pv. tomato DC3000 genomic DNA was used to complement a mutant of Pseudomonas aeruginosa defective in the PilD (XcpA) prepilin peptidase gene by selection for restoration of extracellular protein secretion, a function also known to require PilD. A cosmid able to complement this mutant was also able to complement mutations in the pilB and pilC genes, suggesting that, if the organization of these genes is similar to that of P. aeruginosa, the cosmid may contain the P. syringae pilA. This was confirmed by sequencing a region from this plasmid that was shown to hybridize at low stringency to the P. aeruginosa pilA gene. The deduced P. syringae PilA polypeptide possesses the characteristic properties of the type IV pilins. Heterologous expression of the P. syringae pilA in P. aeruginosa was also shown, conferring not only φ6 phage sensitivity to P. aeruginosa pilA mutants but also sensitivity to PO4, a lytic bacteriophage specific for the pilus of P. aeruginosa. This suggests that additional components might be present in the mature pilus of P. aeruginosa that are the true receptors for this phage. Chromosomal mutations in P. syringae pv. tomato DC3000 pilA and pilD genes were shown to abolish its sensitivity to bacteriophage φ6. To determine the importance of P. syringae pilus in plant leaf interactions, these mutations were tested under laboratory and field conditions. Although little effect was seen on pathogenicity, culturable leaf-associated population sizes of the pilA mutant were significantly different from those of the wild-type parent. In addition, the expression of the DC3000 pilA gene appears to contribute to the UV tolerance of P. syringae and may play a role in survival on the plant leaf surface.


2013 ◽  
Vol 110 (48) ◽  
pp. E4638-E4647 ◽  
Author(s):  
V. Karuppiah ◽  
R. F. Collins ◽  
A. Thistlethwaite ◽  
Y. Gao ◽  
J. P. Derrick

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