The structure of the colony migration factor from pathogenic Proteus mirabilis - A capsular polysaccharide that facilitates swarming

Swarming by Proteus mirabilis is characterized by cycles of rapid and coord inated population migration across surfaces following differentiation of ve getative cells into elongated hyperflagellated swarm cells. It has been sho wn that surface colony expansion by the swarm cell population is facilitate d by a colony migration factor (Cmf), a capsular polysaccharide (CPS) that also contributes to the uropathogenicity of P. mirabilis (Gygi, D., Rahman, M. M., Lai, H.-C., Carlson, R., Guard-Petter, J., and Hughes, C. (1995) Me l. Microbiol. 17, 1167-1175). In this report, the Cmf-CPS was extracted wit h hot water, precipitated with ethanol, and further purified by gel permeat ion chromatography, Its structure was established by glycosyl composition a nd linkage analyses, and by one- and two dimensional NMR spectroscopy. The Cmf-CPS is composed of the following tetrasaccharide repeating unit. [GRAPHICS]