Adherence of pathogens to host cells is critical for the initiation of infection and is thus an attractive target for anti-infective therapeutics and vaccines. In the opportunistic human pathogen Pseudomonas aeruginosa, host-cell adherence is achieved predominantly by type IV pili. Analysis of several clinical strains of P. aeruginosa reveals poor sequence conservation between pilin genes, incl...

Moraxella lacunata and Moraxella bovis use type 4 pili to adhere to epithelial tissues of the cornea and conjunctiva. Primer extension analyses were used to map the transcriptional start sites for the genes encoding the major pilin subunits (tfpQ/I) and the DNA invertase (piv), which determines pilin type expression. tfpQ/I transcription starts at a sigma54-dependent promoter (tfpQ/Ip2) and, un...

UNLABELLED It has been proposed that Geobacter sulfurreducens requires conductive pili for long-range electron transport to Fe(III) oxides and for high-density current production in microbial fuel cells. In order to investigate this further, we constructed a strain of G. sulfurreducens, designated Aro-5, which produced pili with diminished conductivity. This was accomplished by modifying the am...

Bdellovibrio bacteriovorus are facultatively predatory bacteria that grow within gram-negative prey, using pili to invade their periplasmic niche. They also grow prey-independently on organic nutrients after undergoing a reversible switch. The nature of the growth switching mechanism has been elusive, but several independent reports suggested mutations in the hit (host-interaction) locus on the...

The gonococcal pilus is a major virulence factor that has well-established roles in mediating epithelial cell adherence and DNA transformation. Gonococci expressing four gonococcal pilin variants with distinct piliation properties under control of the lac regulatory system were grown in different levels of the inducer isopropyl-beta-D-thiogalactopyranoside (IPTG). These pilin variants expressed...

The attachment of gonococci to mucosal surfaces is of primary importance in their interactions with the genito-urinary tract of the human host. This process may be, in part, mediated by pili, which are proteinaceous appendages emanating from the bacterial cell surface. Observations by Kellogg et al. (1) suggested that certain colonial morphological phenotypes are associated with virulence. Subs...

The attachment of gonococci to mucosal surfaces is of primary importance in their interactions with the genito-urinary tract of the human host. This process may be, in part, mediated by pili, which are proteinaceous appendages emanating from the bacterial cell surface. Observations by Kellogg et al. (1) suggested that certain colonial morphological phenotypes are associated with virulence. Subs...

To provide information useful for the design of a pilus vaccine effective for the prevention of both meningococcal and gonococcal disease, the electron microscopic morphology of meningococcal pili and the structural and antigenic relationships of meningococcal pili to gonococcal pili were investigated. Meningococcal pili were 4-6 nm in width, extended 500-6,000 nm from the organism surface, and...

— Employing a proof technique suggested by Zannier and first successfully implemented by Pila and Zannier to give a reproof of the Manin-Mumford conjecture on algebraic relations on torsion points of an abelian variety, Pila presented an unconditional proof of the André-Oort conjecture when the ambient Shimura variety is a product of modular curves. In subsequent works, these results have been ...