Influence of pH on the expression of a recombinant epoxide hydrolase in Aspergillus niger.

The filamentous fungus Aspergillus niger was investigated in relation to its ability to produce a soluble epoxide hydrolase (EH) (E.C. 3.

Molecular cloning and characterization of a novel UDP-GlcNAc:GalNAc-peptide beta1,3-N-acetylglucosaminyltransferase (beta 3Gn-T6), an enzyme synthesizing the core 3 structure of O-glycans.

The core 3 structure of the O-glycan, GlcNAcbeta1-3GalNAcalpha1-serine/threonine, an important precursor in the biosynthesis of mucin-type glycoproteins, is synthesized by UDP-N-acetylglucosamine:GalNAc-peptide beta1,3-N- acetylglucosaminyltransferase (beta3Gn-T; core 3 synthase). The core 3 structure is restricted in its occurrence to mucins from specific tissues such as the stomach, small intestine, and colon. A partial sequence encoding a novel member of the human beta3Gn-T family was found in one of the data bases.

Characterization of the Immobilized β-Galactosidase C from Bacillus circulans and the Production of β(1→3)-linked Disaccharides.

A recombinant β-galactosidase, which was obtained from the β-galactosidase C gene of Bacillus circulans and cleaves the non-reducing end galactosyl residue of β(1→3)-linkages selectively, was immobilized using CNBr-Sepharose. Although the effect of pH was not changed by the immobilization, the thermostability and stability in the presence of DMF were increased. Optimization of the transglycosylation using para-nitrophenyl β-D-galactopyranoside as a donor and benzyl-α-D-N-acetylgalactosaminide as an acceptor afforded a β(1→3)-linked disaccharide derivative with 62% molar yield in a gram scale synthesis.

Substrate specificity of native dTDP-D-glucose-4,6-dehydratase: chemo-enzymatic syntheses of artificial and naturally occurring deoxy sugars.

Incubation of dTDP-glucose with the enzyme dTDP-glucose-4,6-dehydratase [EC 4.2.1.