Disease relevance of pilP

• The x-ray structure of the FimC-FimH chaperone-adhesin complex from uropathogenic Escherichia coli at 2.5 angstrom resolution reveals the basis for carbohydrate recognition and for pilus assembly [1].
• Conservation of genes encoding components of a type IV pilus assembly/two-step protein export pathway in Neisseria gonorrhoeae [2].
• Mutational analysis of F-pilin reveals domains for pilus assembly, phage infection and DNA transfer [3].
• A peptide library targeting protein-protein interactions crucial for pilus assembly in Gram negative bacteria has been designed using statistical molecular design [4].
• The amino acid sequence encoded by this open reading frame has significant homology to members of the pilus assembly platform protein family, including FhaA of Bordetella pertussis, MrkC of Klebsiella pneumoniae, and the Escherichia coli assembly platform proteins FimD and PapC [5].

High impact information on pilP

• Structure-based site-directed mutagenesis followed by functional studies indicates that VirB5 proteins participate in protein-protein interactions important for pilus assembly and function [6].
• Phenotypes of these mutants indicated that the F-pilin subunit contains specific regions that can be associated with pilus assembly, phage sensitivity and DNA transport [3].
• Gonococcal mutants bearing transposon insertions in these ORFs were non-piliated and failed to express pilus-associated phenotypes, and the corresponding genes were designated PilO and pilP [7].
• PilP- as well as PilQ- mutants shed PilC, a protein which facilitates pilus assembly and is implicated in epithelial cell adherence, in a soluble form [7].
• Furthermore, expression of the cloned N. meningitidis pilC gene in a gonococcal pilC1,2 mutant restores pilus assembly, adherence to ME-180 epithelial cells, and transformation competence to the wild-type level [8].

Biological context of pilP

• Mutating the C-terminal Leu in wt (wild-type) pilin to Ser blocked pilus assembly and fUSE2 infection; the pilin was correctly processed but the level of acetylation at the N terminus appeared to decrease [9].
• SurA is a periplasmic prolyl isomerase/chaperone that facilitates outer membrane protein biogenesis and pilus assembly in E. coli [10].
• Identification of a gene essential for piliation in Haemophilus influenzae type b with homology to the pilus assembly platform genes of gram-negative bacteria [5].
• Thus, the usher N terminus does not function simply as a static binding site for chaperone-subunit complexes but also participates in subsequent pilus assembly events [11].
• The effect of the Tn5 insertions in the bacterial chromosome on pilus assembly was assessed by electron microscopy and sensitivity of mutants to a pilus-specific bacteriophage [12].

Anatomical context of pilP

• Overexpression of FimD(N) in the periplasm of wild-type E.coli cells diminished incorporation of FimH at the tip of type 1 pili, while pilus assembly itself was not affected [13].
• Membranes of hosts carrying the F' mutation contained a full complement of mature F-pilin subunits, so the product of traC is presumably required for pilus assembly but not for pilin processing [14].
• Heterologous expression of TraC in A. tumefaciens partly compensated for the pilus assembly defect in strains deficient for its homolog VirB5, which further supported its role in assembly of conjugative pili [15].

Associations of pilP with chemical compounds

• A second amber mutant (JCFL25) which is not suppressible, carried its mutation in the codon for the single tryptophan in F pilin, suggesting that this residue is important in subunit interactions during pilus assembly [16].

Physical interactions of pilP

• This, together with the deficiency in conjugal DNA transfer, suggests that traC may be part of a membrane-spanning tra protein complex responsible for pilus assembly and disassembly and conjugal DNA transmission [14].

Other interactions of pilP

• A chimera containing the ColB2 pilin gene was able to complement an F traA mutant, demonstrating that the pilus assembly proteins of F can utilize the ColB2 pilin protein to form a pilus [17].
• In this study, we confirm that CooD is required for the initiation of pilus assembly rather than for the stabilization of pili after they are assembled by demonstrating that specific modulation of cooD expression also modulates the number of CS1 pili on bacterial cells [18].
• Complementation analysis employing plasmid deletions revealed a correlation between an N-terminal periplasmic segment of the protein product (TraGp) and its pilus assembly activity [19].

References