Total polyprenols prepared from Pisum stem and analyzed by HPLC, possessed chain-lengths equivalent to 15-17 isoprene units and were (alpha)-saturated. Pea membranes were supplied with GDP- ('14)C mannose, UDP- ('14)C GlcNAc and UDP- ('14)C glucose as substrates for glycosyltransfer in the presence or absence of added polyprenyl phosphates. Mono- and pyro-phosphorylated fractions were characterized using chromatographic and hydrolytic criteria. Glucosyl and mannosyl transfer took place to form endogenous polyprenyl-P-saccharide. Dolichyl-P was the only added polyprenyl phosphate which acted as an acceptor for these transferases. In contrast, incorporation of all the supplied sugars into polyprenyl-PP-saccharide was stimulated greatly in the presence of relatively short (alpha)-saturated polyprenyl phosphates, e.g., dihydro-heptaprenyl phosphate (7HP). A major product was 7H-PP-monosaccharide. / Oligosaccharide-lipids were also synthesized, all of which could be digested by treatment with endo H, indicating the presence of chitobiose. When UDP- ('14)C GlcNAc was used as substrate in the presence of dolP, labelled dol-PP-chitobiose was formed and then lengthened in the presence of unlabelled GDP-mannose. The same oligosaccharides were formed in experiments where the label was present in mannose. Evidence is presented for the further addition of terminal glucose to form "G" oligosaccharide. Endogenous levels of polyprenyl phosphates clearly limited the activities of pea transglycosylases, which were capable of recognizing isoprenoids of particular chain lengths and saturation patterns.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.72053 |
| Date | January 1985 |
| Creators | Torossian, Krikor. |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Doctor of Philosophy (Department of Biology.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 000229159, proquestno: AAINL24054, Theses scanned by UMI/ProQuest. |
Page generated in 0.0024 seconds