PRIMARY STRUCTURE OF THE O-GLYCOSIDICALLY LINKED GLYCAN CHAIN OF THE CRYSTALLINE SURFACE-LAYER GLYCOPROTEIN OF THERMOANAEROBACTER-THERMOHYDROSULFURICUS L111-69 - GALACTOSYL TYROSINE AS A NOVEL LINKAGE UNIT

The products of Pronase digestion of the crystalline surface layer (S- layer) glycoproteins of Thermoanaerobacter thermohydrosulfuricus strai ns L111-69 and L110-69 were isolated by gel permeation chromatography, cation exchange chromatography, chromatofocusing, and reversed phase high performance liquid chromatography. Four compounds were obtained w hich were analyzed by monosaccharide analysis, one- and two-dimensiona l 500 and 600 MHz H-1 and C-13 NMR spectroscopy, methylation analysis, gas-liquid chromatography/mass spectrometry, and matrix-assisted lase r desorption ionization mass spectrometry. For all glycopeptides we pr opose the following glycan structure with galactose as the linkage sug ar. 3-OMeLRhap alpha 1-[4DManp alpha 1-3LRhap alpha 1](n similar to 27 ) -4DManp alpha 1- 3LRhap alpha 1-3LRhap alpha 1-3LRhap alpha 1-3DGalp beta 1-OTyr STRUCTURE 1 The isolated glycopeptides resulted from Pron ase cleavage at the glycosylated tyrosine residues. Tyrosine was found as the linkage amino acid in all fractions but the remaining amino ac id sequences varied, indicating the presence of different glycosylatio n sites in the intact S-layer glycoprotein.