Extracellular oligosaccharides and low-Mr polysaccharides containing (1----2)-beta-D-glucosidic linkages from strains of Xanthomonas, Escherichia coli and Klebsiella pneumoniae.

One strain each of Xanthomonas campestris and 'Xanthomonas phaseoli', three strains of 'Xanthomonas oryzae', and five strains each of Escherichia coli and Klebsiella pneumoniae were found to produce a mixture of (1----2)-beta-D-gluco-oligosaccharides and/or low-Mr (1----2)-beta-D-glucans in their culture media. The saccharides from the strains of Xanthomonas were all composed of unbranched, linear (1----2)-beta-D-glucosaccharides with degrees of polymerization (DPs) of 8 to about 20, and a cyclic (1----2)-beta-D-glucan (DP16) containing one (1----6)-linkage and one alpha-linkage. The saccharides produced by the five strains of E. coli and four strains of K. pneumoniae were glucans with branches at O-6, and DPs of 10 to 15, whereas one strain of K. pneumoniae produced unbranched linear (1----2)-beta-D-glucosaccharides with DPs of 6 to about 20.