Sliding Motility in Mycobacteria

Abstract

Mycobacteria are nonflagellated gram-positive microorganisms. Previously thought to be nonmotile, we show here thatMycobacterium smegmatis can spread on the surface of growth medium by a sliding mechanism. M. smegmatis spreads as a monolayer of cells which are arranged in pseudofilaments by close cell-to-cell contacts, predominantly along their longitudinal axis. The monolayer moves away from the inoculation point as a unit with only minor rearrangements. No extracellular structures such as pili or fimbriae appear to be involved in this process. The ability to translocate over the surface correlates with the presence of glycopeptidolipids, a mycobacterium-specific class of amphiphilic molecules located in the outermost layer of the cell envelope. We present evidence that surface motility is not restricted to M. smegmatis but is also a property of the slow-growing opportunistic pathogen M. avium. This form of motility could play an important role in surface colonization by mycobacteria in the environment as well as in the host.

Biofilm development by clinical strains of non-pigmented rapidly growing mycobacteria

“…Biofilm-producing strains showed a sigmoid growth curve, as previously described for collection strains (Fig. 2) (13). No species differences in growth curves were detected.…”

“…A motility assay was performed as described by Martinez et al [13]. A colony of each strain was inoculated in the centre of a plate of motility medium (Middlebrook 7H9 (BD, Franklin Lakes, NJ, USA) with 0.3% agar (BD) and without supplements).…”

Mycobacteria in drinking water distribution systems: ecology and significance for human health

“…Mycobacteria achieve spreading on surfaces by a sliding mechanism. This form of motility is likely to play an important role in the surface colonization in the environment as well as in the host [187]. The surface properties of cells, in particular determined through glycopeptidolipids, severely affect their ability to spread on solid surfaces [187][188][189].…”

Mycobacterium smegmatisbiofilm formation and sliding motility are affected by the serine/threonine protein kinase PknF

“…Previous studies have shown that GPL-defective mutants like mps [coding for nonribosomal peptide synthetase (Billman-Jacobe et al, 1999;Recht et al, 2000)] and mtf1 [coding for methyl transferase (Recht & Kolter, 2001)] had rough colony morphology. Differences in colony morphology were also shown to be associated with sliding motility (Martinez et al, 1999;Recht & Kolter, 2001;Etienne et al, 2005) and biofilm formation (Recht & Kolter, 2001). We examined the same by assessing the surface spreading assay and attachment of mycobacterial cells to polystyrene surface.…”