The use of bacteriophage-mediated depolymerisation in the structural investigation of the capsular polysaccharide from Escherichia coli serotype K36.

The structure of the repeating unit of the capsular polysaccharide from Escherichia coli serotype K36 has been established from the results of spectroscopic and chemical analyses of (a) P1, the tetrasaccharide obtained on depolymerisation of the polysaccharide with a bacteriophage-borne endo-galactosidase, (b) P1-alditol, and (c) the original polysaccharide. The repeating unit, which is identical to that reported for Klebsiella K57, has the following structure. (Formula: see text).