Substrate specificities of α1,2- And α1,3-galactosyltransferases and characterization of Gmh1p and Otg1p in Schizosaccharomyces pombe

Takamasa Fukunaga, Naotaka Tanaka, Toshio Furumoto, Shinichi Nakakita, Takao Ohashi, Yujiro Higuchi, Hiromi Maekawa, Kaoru Takegawa

Research output: Contribution to journalArticlepeer-review

Abstract

In the fission yeast Schizosaccharomyces pombe, α1,2- and α1,3-linked D-galactose (Gal) residues are transferred to N- and O-linked oligosaccharides of glycoproteins by galactosyltransferases. Although the galactomannans are important for cell-cell communication in S. pombe (e.g., in nonsexual aggregation), the mechanisms underlying galactosylation in cells remain unclear. Schizosaccharomyces pombe has 10 galactosyltransferase-related genes: seven belonging to glycosyltransferase (GT) family 34 and three belonging GT family 8. Disruption of all 10 α-galactosyltransferases (strain Δ10GalT) has been shown to result in a complete lack of α-Gal residues. Here, we have investigated the function and substrate specificities of galactosyltransferases in S pombe by using strains expressing single α-galactosyltransferases in the Δ10GalT background. High-performance liquid chromatography (HPLC) analysis of pyridylaminated O-linked oligosaccharides showed that two GT family 34 α1,2-galactosyltransferases (Gma12p and Gmh6p) and two GT family 8 α1,3-galactosyltransferases (Otg2p and Otg3p) are involved in galactosylation of O-linked oligosaccharide. Moreover, 1H-NMR of N-glycans revealed that three GT family 34 α1,2-galactosyltransferases (Gmh1p, Gmh2p and Gmh3p) are required for the galactosylation of N-linked oligosaccharides. Furthermore, HPLC and lectin-blot analysis revealed that Otg1p showed α1,3-galactosyltransferase activity under conditions of co-expression with Gmh6p, indicating that α-1,2-linked galactose is required for the galactosylation activity of Otg1p in S. pombe. In conclusion, eight galactosyltransferases have been shown to have activity in S. pombe with different substrate specificities. These findings will be useful for genetically tailoring the galactosylation of both N- and O-glycans in fission yeast.

Original languageEnglish
Pages (from-to)1037-1045
Number of pages9
JournalGlycobiology
Volume31
Issue number8
DOIs
Publication statusPublished - Aug 1 2021

All Science Journal Classification (ASJC) codes

  • Biochemistry

Fingerprint

Dive into the research topics of 'Substrate specificities of α1,2- And α1,3-galactosyltransferases and characterization of Gmh1p and Otg1p in Schizosaccharomyces pombe'. Together they form a unique fingerprint.

Cite this