Myxococcus xanthus performs coordinated social motility of cell groups through the extension and retraction of type IV pili (TFP) on solid surfaces, which requires both TFP and exopolysaccharides (EPS). By submerging cells in a liquid medium containing 1% methylcellulose, M. xanthus TFP-driven motility was induced in isolated cells and independently of EPS.
View Article and Find Full Text PDFWe show that Vibrio cholerae, the causative agent of cholera, use their flagella and mannose-sensitive hemagglutinin (MSHA) type IV pili synergistically to switch between two complementary motility states that together facilitate surface selection and attachment. Flagellar rotation counter-rotates the cell body, causing MSHA pili to have periodic mechanical contact with the surface for surface-skimming cells. Using tracking algorithms at 5 ms resolution we observe two motility behaviours: 'roaming', characterized by meandering trajectories, and 'orbiting', characterized by repetitive high-curvature orbits.
View Article and Find Full Text PDFBacterial biofilms are surface-associated, multicellular, morphologically complex microbial communities. Biofilm-forming bacteria such as the opportunistic pathogen Pseudomonas aeruginosa are phenotypically distinct from their free-swimming, planktonic counterparts. Much work has focused on factors affecting surface adhesion, and it is known that P.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
February 2013
Myxococcus xanthus is a bacterium capable of complex social organization. Its characteristic social ("S")-motility mechanism is mediated by type IV pili (TFP), linear actuator appendages that propel the bacterium along a surface. TFP are known to bind to secreted exopolysaccharides (EPS), but it is unclear how M.
View Article and Find Full Text PDFBacteria optimize the use of their motility appendages to move efficiently on a wide range of surfaces prior to forming multicellular bacterial biofilms. The "twitching" motility mode employed by many bacterial species for surface exploration uses type-IV pili (TFP) as linear actuators to enable directional crawling. In addition to linear motion, however, motility requires turns and changes of direction.
View Article and Find Full Text PDFBacterial biofilms are structured multicellular communities that are responsible for a broad range of infections. Knowing how free-swimming bacteria adapt their motility mechanisms near a surface is crucial for understanding the transition from the planktonic to the biofilm phenotype. By translating microscopy movies into searchable databases of bacterial behavior and developing image-based search engines, we were able to identify fundamental appendage-specific mechanisms for the surface motility of Pseudomonas aeruginosa.
View Article and Find Full Text PDFBacterial biofilms are structured multicellular communities involved in a broad range of infections. Knowing how free-swimming bacteria adapt their motility mechanisms near surfaces is crucial for understanding the transition between planktonic and biofilm phenotypes. By translating microscopy movies into searchable databases of bacterial behavior, we identified fundamental type IV pili-driven mechanisms for Pseudomonas aeruginosa surface motility involved in distinct foraging strategies.
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