STRUCTURE OF THE PHOSPHOPEPTIDOMANNANS FROM FLOCCULANT AND NONFLOCCULANT YEAST KLUYVEROMYCES-LACTIS

After extraction from whole cells, and purification by gel filtration, the chemical composition and molecular mass estimation of the cell-wa ll phosphopeptidomannan (PPM) showed no significant difference respect ively between flocculent, weakly, very weakly and non-flocculent Kluyu eromyces lactis yeast strains. However, when PPMs were tested as ligan ds of a lectin, extracted from the flocculent strain, the PPM isolated from the flocculent and weakly flocculent strain were recognized to a higher degree than those isolated from the non and very weakly floccu lent strains. Acetolysis of PPM extracted From the four strains produc ed five oligosaccharide fractions corresponding to mono-, di-, tri-, p enta-and hexa-saccharides. The flocculent strain was characterised by a high content of di-and penta-saccharides, The H-1 NMR analysis of th e oligosaccharides demonstrated that the flocculent strain contained e quivalent levels of the two mannobioses: Man(alpha 1 --> 2)Man and Man (alpha 1 --> 3)Man and of the two mannotrioses Man(alpha 1 --> 2)Man(a lpha 1 --> 2)Man and Man(alpha 1 --> 3)Man(alpha 1 --> 2)Man. In contr ast, the non-flocculent and the very weakly flocculent strains contain ed a single type of mannobiose Man(alpha 1 --> 2)Man and one type of m annotriose Man(alpha 1 --> 2)Man(alpha 1 --> 2)Man.