A variety of bacterial pathogens use nanoscale protein fibers called type IV pili to mediate cell adhesion, a primary step leading to infection. Currently, how these nanofibers respond to mechanical stimuli and how this response is used to control adhesion is poorly understood. Here, we use atomic force microscopy techniques to quantify the forces guiding the adhesion of Pseudomonas aeruginosa ...

Escherichia coli with mannose-resistant (MR) pili, in contrast to those with mannose-sensitive (MS) pili, did not adhere to rat peritoneal macrophages and human polymorphonuclear granulocytes, as measured by use of radioactive bacteria and by the chemiluminescence response induced by the cell contact. With some MS-piliated E. coli strains, unpiliated bacteria, obtained by growth at a pilus-rest...

CooD, the minor subunit of CS1 pili of enterotoxigenic Escherichia coli, is essential for the assembly of stable, functional pili. We previously proposed that CooD is a rate-limiting initiator of CS1 pilus assembly and predicted that the level of CooD expression should therefore determine the number of CS1 pili assembled on the cell surface. In this study, we confirm that CooD is required for t...

Pili from enterotoxigenic Escherichia coli pathogenic for humans have been isolated by adsorption to the surface of erythrocytes followed by thermal elution. The pili are composed of two protein subunits with molecular weights of 13,100 and 12,500 as determined by sodium dodecyl sulfate-gel electrophoresis. These pili also bind to human buccal cells under temperature conditions (37 degrees C) w...

It is critical for bacteria to recognize surface contact and initiate physiological changes required for surface-associated lifestyles. Ubiquitous microbial appendages called pili are involved in sensing surfaces and facilitating downstream behaviors, but the mechanism by which pili mediate surface sensing has been unclear. We visualized Caulobacter crescentus pili undergoing dynamic cycles of ...

Guinea pigs were immunized with either alpha or beta pili from Neisseria gonorrhoeae P9 before the inoculation of subcutaneous chambers with a mixture of variants having alpha, beta, gamma, or delta pili. Animals immunized with alpha pili showed significant protection, but those immunized with beta pili did not. The degree of protection could be correlated with the cross-reactivity of the antib...

Conjugative pili are widespread bacterial appendages that play important roles in horizontal gene transfer, in spread of antibiotic resistance genes, and as sites of phage attachment. Among conjugative pili, the F "sex" pilus encoded by the F plasmid is the best functionally characterized, and it is also historically the most important, as the discovery of F-plasmid-mediated conjugation ushered...

Pilus of Vibrio parahaemolyticus O3:K6 strain LVP9 belonging to the newly identified clone was purified and characterized. The molecular mass of the pilin was estimated to be about 18 kDa by SDS-PAGE, and the isoelectric point of the pilin was 5.0 +/- 0.2. The LVP9 pili were antigenically different from the other V. parahaemolyticus Na2 pili and Ha7 pili as previously reported, nevertheless all...

Electricity generation by Geobacter sulfurreducens biofilms grown on electrodes involves matrix-associated electron carriers, such as c-type cytochromes. Yet, the contribution of the biofilm's conductive pili remains uncertain, largely because pili-defective mutants also have cytochrome defects. Here we report that a pili-deficient mutant carrying an inactivating mutation in the pilus assembly ...

The presence of pili in human and animal parasites and pathogens of the genus Corynebacterium was examined. C. kutscheri, C. diphtheriae, and C. pseudodiphtheriticum possessed a fairly large number of pili, ranging from dozens to more than a hundred, in 91 to 100% of the bacterial cells. C. equi, C. hoagii, C. xerosis, C. pyogenes, and C. murisepticum had only a small number of pili in 10 to 37...