Type IV Pili and Exopolysaccharide-dependent Motility in Myxococcus xanthus
Zhaomin Yang, Chengyun Li, Carmen Friedrich and Lotte Søgaard-Andersen
from: Myxobacteria: Genomics, Cellular and Molecular Biology (Edited by: Zhaomin Yang and Penelope I. Higgs). Caister Academic Press, U.K. (2014)
Social (S) motility of Myxococcus xanthus was discovered in the late 1970's. In the last few decades, especially since the mid-1990's, great strides have been made in our understanding of the molecular mechanisms underlying this form of motility. It is now well established that M. xanthus S-motility as well as twitching motility in other bacteria rely on the retraction of the type IV pilus (T4P) to bring about cell translocation. In fact, T4P retraction generates the strongest force ever measured for a biological motor. In this chapter, we review the landmark studies leading to the conclusion that T4P retraction powers these forms of bacterial surface locomotion. The structure of the T4P system in comparison with the type II secretion system is discussed as they are evolutionally related. We additionally describe the requirement of of M. xanthus S-motility for exopolysaccharides. We will conclude by highlighting some of the unanswered questions, with special attention to M. xanthus T4P-dependent motility read more ...