Enzymic O-glycosylation of synthetic peptides from sequences in basic myelin protein.
Nine synthetic peptides containing sequences in the region of a threonine residue at position 98 of bovine basic myelin protein were prepared by the Merrifield solid-phase method and tested for their ability to be glycosylated with [14C]uridinediphospho-N-acetylgalactosamine and a crude detergent-solubilized preparation of uridinediphospho-N-acetylgalactosamine:mucin polypeptide N-acetylgalactosaminyltransferase obtained from porcine submaxillary glands. The tetrapeptide Thr-Pro-Pro-Pro and all larger peptides containing this sequence were glycosylated. The glycosylation was greater for peptides containing residues N-terminal to the Thr-Pro-Pro-Pro. Under the conditions used, the peptide Val-Thr-Pro-Arg-Thr-Pro-Pro-Pro was glycoslyated twice as much as bovine basic myelin protein. Thr-Pro and Thr-Pro-Pro, as well as 10 other synthetic peptides which did not contain the Thr-Pro-Pro-Pro sequence, were not glycosylated. Treatment of the glycopeptide of Phe-Lys-Asn-Leu-Val-Thr-Pro-Arg-Thr-Pro-Pro-Pro-Ser with an alpha-N-acetylgalactosaminidase released N-acetylgalactosamine from the peptide, indicating that the hexosamine was covalently bonded to the peptide in an alpha linkage.
D000595:Amino Acid Sequence; D000818:Animals; D002855:Chromatography, Thin Layer; D005700:Galactosyltransferases / Q000378:metabolism*; D006027:Glycosides / Q000096:biosynthesis*; D009077:Mucins; D004676:Myelin Basic Protein; D017350:N-Acetylgalactosaminyltransferases; D009842:Oligopeptides; D013363:Submandibular Gland / Q000201:enzymology; D000097763:Polypeptide N-acetylgalactosaminyltransferase
D005700:Galactosyltransferases; D006027:Glycosides; D009077:Mucins; D004676:Myelin Basic Protein; D017350:N-Acetylgalactosaminyltransferases; D009842:Oligopeptides; D000097763:Polypeptide N-acetylgalactosaminyltransferase