Apicomplexan parasites are thought to actively invade the host cell by gliding motility. This movement is powered by the parasite's own actomyosin system, and depends on the regulated polymerisation and depolymerisation of actin to generate the force for gliding and host cell penetration. Recent studies demonstrated that Toxoplasma gondii can invade the host cell in the absence of several core ...

The human pathogen Mycoplasma genitalium is known to mediate cell adhesion to target cells by the attachment organelle, a complex structure also implicated in gliding motility. The gliding mechanism of M. genitalium cells is completely unknown, but recent studies have begun to elucidate the components of the gliding machinery. We report the study of MG312, a cytadherence-related protein contain...

Mycoplasma gallisepticum, the most pathogenic mycoplasma in poultry, is able to glide over solid surfaces. Although this gliding motility was first observed in 1968, no specific protein has yet been shown to be involved in gliding. We examined M. gallisepticum strains and clonal variants for motility and found that the cytadherence proteins GapA and CrmA were required for gliding. Loss of GapA ...

The effects of selected metabolic and respiratory inhibitors on the gliding motility of Flexibacter polymorphus were examined. Motility and oxygen consumption were quantitatively inhibited in a reversible manner by specific respiratory poisons, suggesting that gliding velocity was linked to electron transport activity. Arsenate had little influence on the number or rate of gliding filaments, de...

A protein with a molecular mass of 42 kDa (P42) from Mycoplasma mobile, one of several mycoplasmas that exhibit gliding motility, was shown to be a novel NTPase (nucleoside triphosphatase). Although the P42 protein lacks a common ATP-binding sequence motif (Walker A), the recombinant proteins expressed in Escherichia coli certainly hydrolysed some nucleoside triphosphates, including ATP. The re...

Gliding motility is observed in a large variety of phylogenetically unrelated bacteria. Gliding provides a means for microbes to travel in environments with a low water content, such as might be found in biofilms, microbial mats, and soil. Gliding is defined as the movement of a cell on a surface in the direction of the long axis of the cell. Because this definition is operational and not mecha...

Myxococcus xanthus cells move on a solid surface by gliding motility. Several genes required for gliding motility have been identified, including those of the A- and S-motility systems as well as the mgl and frz genes. However, the cellular defects in gliding movement in many of these mutants were unknown. We conducted quantitative, high-resolution single-cell motility assays and found that mut...

Cells of the gliding bacterium Flavobacterium johnsoniae move rapidly over surfaces by an unknown mechanism. Transposon insertions in sprB resulted in cells that were defective in gliding. SprB is a highly repetitive 669-kDa cell surface protein, and antibodies against SprB inhibited the motility of wild-type cells. Polystyrene microspheres coated with antibodies against SprB attached to and we...

T. gondii uses substrate-dependent gliding motility to invade cells of its hosts, egress from these cells at the end of its lytic cycle and disseminate through the host organism during infection. The ability of the parasite to move is therefore critical for its virulence. T. gondii engages in three distinct types of gliding motility on coated two-dimensional surfaces: twirling, circular gliding...

Apicomplexans such as Toxoplasma gondii actively invade host cells using a unique parasite-dependent mechanism termed gliding motility. Calcium-mediated protein secretion by the parasite has been implicated in this process, but the precise role of calcium signaling in motility remains unclear. Here we used calmidazolium as a tool to stimulate intracellular calcium fluxes and found that this dru...