FORMATION OF LYSO-GLYCOSPHINGOLIPIDS BY STREPTOMYCES SP

The actinomycete strain Streptomyces sp. H37 produces a novel glycosph ingolipid-degrading enzyme. This strain was capable of converting gang lioside GM1 to lyso-GM1. After cultivation for 5 days in medium contai ning GM1, peptone, and detergent, GM1 was found to be almost completel y converted to lyso-GM1. The product was purified on a DEAE-Sephadex A -25 column and thin layer chromatographies. The purified lyso-GM1 was hydrolyzed by endoglycoceramidase, and the released oligosaccharide mo iety was identified as that of GM1 by HPLC using the pyridylaminoderiv ative method. The counterpart sphingosine moiety was confirmed with TL C, Moreover, the structure of lyso-GM1 was ascertained by H-1-NMR anal ysis, The maximum formation of lyso-GM1 was found in 50 mM potassium p hosphate buffer (pH 7.5) containing 0.1% glycodeoxycholate. Various ly so-glycoshingolipids, including those of ganglio-, neolacto-, and glob e-types, were formed from their parent glycosphingolipids using this s train.