Faculty Opinions recommendation of Identification of a novel type IV pilus gene cluster required for gastrointestinal colonization of Citrobacter rodentium.

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.

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Yersinia pseudotuberculosis Harbors a Type IV Pilus Gene Cluster That Contributes to Pathogenicity

Infection and Immunity ◽

10.1128/iai.70.11.6196-6205.2002 ◽

2002 ◽

Vol 70 (11) ◽

pp. 6196-6205 ◽

Cited By ~ 61

Author(s):

François Collyn ◽

Marie-Annick Léty ◽

Shamila Nair ◽

Vincent Escuyer ◽

Amena Ben Younes ◽

...

Keyword(s):

Gene Cluster ◽

Yersinia Pseudotuberculosis ◽

Open Reading Frames ◽

Host Cells ◽

Gram Negative Bacteria ◽

Type Iv Pilus ◽

Chromosomal Locus ◽

Bacterial Surface ◽

Type Iv ◽

Reading Frames

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.

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

Journal of Bacteriology ◽

10.1128/jb.00722-07 ◽

2007 ◽

Vol 189 (24) ◽

pp. 9145-9149 ◽

Cited By ~ 22

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.

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Demonstration of Type IV Pilus Expression and a Twitching Phenotype by Haemophilus influenzae

Infection and Immunity ◽

10.1128/iai.73.3.1635-1643.2005 ◽

2005 ◽

Vol 73 (3) ◽

pp. 1635-1643 ◽

Cited By ~ 82

Author(s):

Lauren O. Bakaletz ◽

Beth D. Baker ◽

Joseph A. Jurcisek ◽

Alistair Harrison ◽

Laura A. Novotny ◽

...

Keyword(s):

Haemophilus Influenzae ◽

Gene Cluster ◽

Defined Medium ◽

Type Iv Pili ◽

Homologous Gene ◽

Type Ii Secretion ◽

Twitching Motility ◽

Type Iv Pilus ◽

Type Iv ◽

Prepilin Peptidase

ABSTRACT Haemophilus influenzae is considered a nonmotile organism that expresses neither flagella nor type IV pili, although H. influenzae strain Rd possesses a cryptic pilus locus. We demonstrate here that the homologous gene cluster pilABCD in an otitis media isolate of nontypeable H. influenzae strain 86-028NP encodes a surface appendage that is highly similar, structurally and functionally, to the well-characterized subgroup of bacterial pili known as type IV pili. This gene cluster includes a gene (pilA) that likely encodes the major subunit of the heretofore uncharacterized H. influenzae-expressed type IV pilus, a gene with homology to a type IV prepilin peptidase (pilD) as well as two additional uncharacterized genes (pilB and pilC). A second gene cluster (comABCDEF) was also identified by homology to other pil or type II secretion system genes. When grown in chemically defined medium at an alkaline pH, strain 86-028NP produces approximately 7-nm-diameter structures that are near polar in location. Importantly, these organisms exhibit twitching motility. A mutation in the pilA gene abolishes both expression of the pilus structure and the twitching phenotype, whereas a mutant lacking ComE, a Pseudomonas PilQ homologue, produced large appendages that appeared to be membrane bound and terminated in a slightly bulbous tip. These latter structures often showed a regular pattern of areas of constriction and expansion. The recognition that H. influenzae possesses a mechanism for twitching motility will likely profoundly influence our understanding of H. influenzae-induced diseases of the respiratory tract and their sequelae.

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Molecular analysis of VcfQ protein involved in Vibrio cholerae type IV pilus biogenesis

Journal of Medical Microbiology ◽

10.1099/jmm.0.04967-0 ◽

2003 ◽

Vol 52 (4) ◽

pp. 283-288 ◽

Cited By ~ 2

Author(s):

Tomoko Miyazato ◽

Claudia Toma ◽

Noboru Nakasone ◽

Koichiro Yamamoto ◽

Masaaki Iwanaga

Keyword(s):

Vibrio Cholerae ◽

Gene Cluster ◽

Mutational Analysis ◽

Cell Fractionation ◽

Deficient Mutant ◽

Type Iv Pilus ◽

Outer Membranes ◽

Type Iv ◽

Pilus Biogenesis ◽

Immunological Cross Reaction

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.

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Faculty Opinions recommendation of The Che4 pathway of Myxococcus xanthus regulates type IV pilus-mediated motility.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1019833.226437 ◽

2004 ◽

Author(s):

George Ordal

Keyword(s):

Myxococcus Xanthus ◽

Type Iv Pilus ◽

Type Iv

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A Type II Protein Secretory Pathway Required for Levansucrase Secretion by Gluconacetobacter diazotrophicus

Journal of Bacteriology ◽

10.1128/jb.186.15.5031-5039.2004 ◽

2004 ◽

Vol 186 (15) ◽

pp. 5031-5039 ◽

Cited By ~ 26

Author(s):

Juan G. Arrieta ◽

Mailin Sotolongo ◽

Carmen Menéndez ◽

Dubiel Alfonso ◽

Luis E. Trujillo ◽

...

Keyword(s):

Codon Usage ◽

Outer Membrane ◽

Gene Cluster ◽

Secretory Pathway ◽

Cosmid Library ◽

Polymorphism Analysis ◽

Type Ii ◽

Gluconacetobacter Diazotrophicus ◽

Type Iv ◽

Geographical Regions

ABSTRACT The endophytic diazotroph Gluconacetobacter diazotrophicus secretes a constitutively expressed levansucrase (LsdA, EC 2.4.1.10) to utilize plant sucrose. LsdA, unlike other extracellular levansucrases from gram-negative bacteria, is transported to the periplasm by a signal-peptide-dependent pathway. We identified an unusually organized gene cluster encoding at least the components LsdG, -O, -E, -F, -H, -I, -J, -L, -M, -N, and -D of a type II secretory system required for LsdA translocation across the outer membrane. Another open reading frame, designated lsdX, is located between the operon promoter and lsdG, but it was not identified in BLASTX searches of the DDBJ/EMBL/GenBank databases. The lsdX, -G, and -O genes were isolated from a cosmid library of strain SRT4 by complementation of an ethyl methanesulfonate mutant unable to transport LsdA across the outer membrane. The downstream genes lsdE, -F, -H, -I, -J, -L, -M, -N, and -D were isolated through chromosomal walking. The high G+C content (64 to 74%) and the codon usage of the genes identified are consistent with the G+C content and codon usage of the standard G. diazotrophicus structural gene. Sequence analysis of the gene cluster indicated that a polycistronic transcript is synthesized. Targeted disruption of lsdG, lsdO, or lsdF blocked LsdA secretion, and the bacterium failed to grow on sucrose. Replacement of Cys162 by Gly at the C terminus of the pseudopilin LsdG abolished the protein functionality, suggesting that there is a relationship with type IV pilins. Restriction fragment length polymorphism analysis revealed conservation of the type II secretion operon downstream of the levansucrase-levanase (lsdA-lsdB) locus in 14 G. diazotrophicus strains representing 11 genotypes recovered from four different host plants in diverse geographical regions. To our knowledge, this is the first report of a type II pathway for protein secretion in the Acetobacteraceae.

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