Bacterial motility | EPFL Graph Search

Bacterial motility is the ability of bacteria to move independently using metabolic energy. Most motility mechanisms which evolved among bacteria also evolved in parallel among the archaea. Most rod-shaped bacteria can move using their own power, which allows colonization of new environments and discovery of new resources for survival. Bacterial movement depends not only on the characteristics of the medium, but also on the use of different appendages to propel. Swarming and swimming movements are both powered by rotating flagella. Whereas swarming is a multicellular 2D movement over a surface and requires the presence of surfactants, swimming is movement of individual cells in liquid environments. Other types of movement occurring on solid surfaces include twitching, gliding and sliding, which are all independent of flagella. Twitching depends on the extension, attachment to a surface, and retraction of type IV pili which pull the cell forwards in a manner similar to the action of a grappling hook, providing energy to move the cell forward. Gliding uses different motor complexes, such as the focal adhesion complexes of Myxococcus. Unlike twitching and gliding motilities, which are active movements where the motive force is generated by the individual cell, sliding is a passive movement. It relies on the motive force generated by the cell community due to the expansive forces caused by cell growth within the colony in the presence of surfactants, which reduce the friction between the cells and the surface. The overall movement of a bacterium can be the result of alternating tumble and swim phases. As a result, the trajectory of a bacterium swimming in a uniform environment will form a random walk with relatively straight swims interrupted by random tumbles that reorient the bacterium. Bacteria can also exhibit taxis, which is the ability to move towards or away from stimuli in their environment. In chemotaxis the overall motion of bacteria responds to the presence of chemical gradients.

Multiscale Porosity Microfluidics to Study Bacterial Transport in Heterogeneous Chemical Landscapes

Francesco Carrara, Jiande Zhou

Microfluidic models are proving to be powerful systems to study fundamental processes in porous media, due to their ability to replicate topologically complex environments while allowing detailed, quantitative observations at the pore scale. Yet, while por ...

Hoboken2024

Two antagonistic response regulators control Pseudomonas aeruginosa polarization during mechanotaxis

Alexandre Louis André Persat, Lorenzo Anton-Louis Talà, Xavier Jean-Yves Pierrat, Joanne Netter Engel, Marco Julian Kühn

The opportunistic pathogen Pseudomonas aeruginosa adapts to solid surfaces to enhance virulence and infect its host. Type IV pili (T4P), long and thin filaments that power surface-specific twitching motility, allow single cells to sense surfaces and contro ...

WILEY2023

Material Substrate Physical Properties Control Pseudomonas aeruginosa Biofilm Architecture

Alexandre Louis André Persat, Alice Cont

The biofilm lifestyle is the most widespread survival strategy in the bacterial world. Pseudomonas aeruginosa biofilms cause chronic infections and are highly recalcitrant to antimicrobials. The genetic requirements allowing P. aeruginosa to grow into biof ...

AMER SOC MICROBIOLOGY2023