Mucin biosynthesis enzymic properties of human-tracheal epithelial GDP-l-fucose:β-d-galactoside α-(1→2)-l-fucosyltransferase

Pi Wan Cheng, Arthur DeVries

Research output: Contribution to journalArticlepeer-review

5 Scopus citations

Abstract

The human-tracheal, epithelial α-(1→2)-l-fucosyltransferase that transfers l-fucose from GDP-l-fucose to an acceptor containing a β-d-galactopyranosyl group at the nonreducing terminal was characterized. Optimal enzyme activity was obtained at pH 6.5. 20-30mm MnCl2 (or CaCl2, and 0.05% Triton X-100 or 0.5% Tween 20. Mg2+ and Ba2+ ions moderately enhanced the enzyme activity, whereas Fe2+, Co2+, Zn2+, and Cd2+ ions were inhibitory. The enzyme activity was inhibited by N-ethylmaleimide and nucleotides of guanine, inosine, xanthine, and uridine. However, ATP and dithiothreitol did not affect the enzyme activity. The apparent Michaelis constant for GDP-l-fucose, freezing point-depressing glycoproteins (expressed as Gal→GalNAc→Thr), and phenyl β-d-galactopyranoside was 0.29, 5.70, and 25.4mm, respectively. Under alkali-borohydride conditions (0.05m NaOHM NaBH4, 45°, 20 h), an l-[14C]fucosyltrisaccharide was released from the product obtained by use of freezing point-depressing glycoprotein as the acceptor. The α-l anomeric configuration of the fucoside was determined by the release of l-[14C]fucose from the purified trisaccharide by Turbo cornutus α-l-fucosidase. The (1→2) linkage of the l-fucosyl group to the d-galactosyl residue was established by methylation technique (m.s.-g.l.c.). The present enzyme has properties similar to those of the human milk α-(1→2)-l-fucosyltransferase which is encoded by a secretor gene.

Original languageEnglish (US)
Pages (from-to)253-261
Number of pages9
JournalCarbohydrate Research
Volume149
Issue number1
DOIs
StatePublished - Jun 1 1986

ASJC Scopus subject areas

  • Analytical Chemistry
  • Biochemistry
  • Organic Chemistry

Fingerprint Dive into the research topics of 'Mucin biosynthesis enzymic properties of human-tracheal epithelial GDP-l-fucose:β-d-galactoside α-(1→2)-l-fucosyltransferase'. Together they form a unique fingerprint.

Cite this