Molecular Cloning and Expression of Endo-.BETA.-N-Acetylglucosaminidase D, Which Acts on the Core Structure of Complex Type Asparagine-Linked Oligosaccharides.

概要

論文の詳細を見る
Endo-β-N-acetylglucosaminidase D (Endo D) produced by Streptococcus pneumoniae cleaves the di-N-acetylchitobiose structure in asparagine-linked oligosaccharides. The enzyme generally acts on complex type oligosaccharides after removal of external sugars by neuraminidase, β-galactosidase, and β-N-acetylglucosaminidase. We cloned the gene encoding the enzyme and expressed it as a periplasm enzyme in Escherichia coli. The first 37 amino acids in the predicted sequence are removed in the mature enzyme, yielding a protein with a molecular mass of 178 kDa. The substrate specificity of the recombinant enzyme is indistinguishable from the enzyme produced by S. pneumoniae. Endo-β-N-acetylglucosaminidase A (Endo A) from Arthrobacter protophormiae, the molecular mass of which is 72 kDa, had 32% sequence identity to Endo D, starting from the N-terminal sides of both enzymes, although Endo A hydrolyzes high-mannose-type oligosaccharides and does not hydrolyze complex type ones. Endo D is not related to endo-β-N-acetylglucosaminidases H, F1, F2, or F3, which share common structural motifs. Therefore, there are two distinct groups of endo-β-N-acetylglucosaminidases acting on asparagine-linked oligosaccharides. The C-terminal region of Endo D shows homology to β-galactosidase and β-N-acetylglucosaminidase from S. pneumoniae and has an LPXTG motif typical of surface-associated proteins of Gram-positive bacteria. It is possible that Endo D is located on the surface of the bacterium and, together with other glycosidases, is involved in virulence.
社団法人日本生化学会の論文

Molecular Cloning and Expression of Endo-.BETA.-N-Acetylglucosaminidase D, Which Acts on the Core Structure of Complex Type Asparagine-Linked Oligosaccharides.

スポンサーリンク

概要

著者

関連論文

スポンサーリンク