Motor-driven intracellular transport powers bacterial gliding motility. Author Mingzhai Sun, Morgane Wartel, Eric Cascales, Joshua Shaevitz, Tâm Mignot Publication Year 2011 Type Journal Article Abstract Protein-directed intracellular transport has not been observed in bacteria despite the existence of dynamic protein localization and a complex cytoskeleton. However, protein trafficking has clear potential uses for important cellular processes such as growth, development, chromosome segregation, and motility. Conflicting models have been proposed to explain Myxococcus xanthus motility on solid surfaces, some favoring secretion engines at the rear of cells and others evoking an unknown class of molecular motors distributed along the cell body. Through a combination of fluorescence imaging, force microscopy, and genetic manipulation, we show that membrane-bound cytoplasmic complexes consisting of motor and regulatory proteins are directionally transported down the axis of a cell at constant velocity. This intracellular motion is transmitted to the exterior of the cell and converted to traction forces on the substrate. Thus, this study demonstrates the existence of a conserved class of processive intracellular motors in bacteria and shows how these motors have been adapted to produce cell motility. Keywords Blotting, Western, Immunoprecipitation, Models, Biological, Electroporation, Plasmids, Molecular Motor Proteins, Protein Transport, Adenosine Triphosphate, Fluorescence, Fluoresceins, Focal Adhesions, Hydrogen-Ion Concentration, Kymography, Locomotion, Microspheres, Myxococcus xanthus Journal Proc Natl Acad Sci U S A Volume 108 Issue 18 Pages 7559-64 Date Published 05/2011 Alternate Journal Proc. Natl. Acad. Sci. U.S.A. Google ScholarBibTeXEndNote X3 XML