50787-11-6Relevant academic research and scientific papers
Modulation of acceptor specificity of Ruminococcus albus cellobiose phosphorylase through site-directed mutagenesis
Hamura, Ken,Saburi, Wataru,Matsui, Hirokazu,Mori, Haruhide
, p. 21 - 25 (2013)
Cellobiose phosphorylase (EC 2.4.1.20, CBP) catalyzes the reversible phosphorolysis of cellobiose to α-D-glucose 1-phosphate (Glc1P) and D-glucose. Cys485, Tyr648, and Glu653 of CBP from Ruminococcus albus, situated at the +1 subsite, were mutated to modulate acceptor specificity. C485A, Y648F, and Y648V were active enough for analysis. Their acceptor specificities were compared with the wild type based on the apparent kinetic parameters determined in the presence of 10 mM Glc1P. C485A showed higher preference for D-glucosamine than the wild type. Apparent kcat/Km values of Y648F for D-mannose and 2-deoxy-D-glucose were 8.2- and 4.0-fold higher than those of the wild type, respectively. Y648V had synthetic activity toward N-acetyl-D-glucosamine, while the other variants did not. The oligosaccharide production in the presence of the same concentrations of wild type and each mutant was compared. C485A produced 4-O-β-D-glucopyranosyl-D-glucosamine from 10 mM Glc1P and D-glucosamine at a rate similar to the wild type. Y648F and Y648V produced 4-O-β-D-glucopyranosyl-D-mannose and 4-O-β-D- glucopyranosyl-N-acetyl-D-glucosamine much more rapidly than the wild type when D-mannose and N-acetyl-D-glucosamine were used as acceptors, respectively. After a 4 h reaction, the amounts of 4-O-β-D-glucopyranosyl-D-mannose and 4-O-β-D-glucopyranosyl-N-acetyl-D-glucosamine produced by Y648F and Y648V were 5.9- and 12-fold higher than the wild type, respectively.
Two-Step Chemoenzymatic Detection of N-Acetylneuraminic Acid-α(2-3)-Galactose Glycans
Wen, Liuqing,Zheng, Yuan,Jiang, Kuan,Zhang, Mingzhen,Kondengaden, Shukkoor Muhammed,Li, Shanshan,Huang, Kenneth,Li, Jing,Song, Jing,Wang, Peng George
supporting information, p. 11473 - 11476 (2016/10/07)
Sialic acids are typically linked α(2-3) or α(2-6) to the galactose that located at the non-reducing terminal end of glycans, playing important but distinct roles in a variety of biological and pathological processes. However, details about their respective roles are still largely unknown due to the lack of an effective analytical technique. Herein, a two-step chemoenzymatic approach for the rapid and sensitive detection of N-acetylneuraminic acid-α(2-3)-galactose glycans is described.
Bio-solvents change regioselectivity in the synthesis of disaccharides using Biolacta β-galactosidase
Pérez-Sánchez, María,Sandoval, Manuel,Hernáiz, María J.
experimental part, p. 2141 - 2145 (2012/03/27)
Bio-solvents are good alternative solvents that avoid the use of classical organic solvents when performing enzymatic reactions. A noticeably change in regioselectivity was observed in the synthetic behaviour of Biolacta β-galactosidase using bio-solvents derived from dimethylamide and glycerol as co-solvents. Under these conditions, the enzyme changes its well known tendency to produce β-(1→4) to β-(1→6) disaccharides. An evaluation of the bio-solvent concentration and the effects of the non proteic additives in commercially available Biolacta β-galactosidase was undertaken in order to optimize the reaction conditions to improve the yield of the β-(1→6) product.
Regioselectivity in β-galactosidase-catalyzed transglycosylation for the enzymatic assembly of D-galactosyl-D-mannose
Miyasato, Mariko,Ajisaka, Katsumi
, p. 2086 - 2090 (2007/10/03)
The regioselectivity of β-galactosidase derived from Bacillus circulans ATCC 31382 (β-1,3-galactosidase) in transgalactosylation reactions using D-mannose as an acceptor was investigated. This D-mannose associated regioselectivity was found to be different from reactions using either GlcNAc or GalNAc as acceptors, not only for β-1,3-galactosidase but also for β-galactosidases of different origins. The relative hydrolysis rate of Galβ-pNP and D-galactosyl-D-mannoses, of various linkages, was also measured in the presence of β-1,3-galactosidase and was found to correlate well with the ratio of disaccharides formed by transglycosylation. The unexpected regioselectivity using D-mannose can therefore be explained by an anomalous specificity in the hydrolysis reaction. By utilizing the identified characteristics of both regioselectivity and hydrolysis specificity using D-mannose, an efficient method for enzymatic synthesis of β-1,3-, β-1,4- and β-1,6-linked D-galactosyl-D-mannose was subsequently established.
NMR assignments for glucosylated and galactosylated N- acetylhexosaminitols: Oligosaccharide alditols related to O-linked glycans from the protozoan parasite Trypanosoma cruzi
Jones, Christopher,Previato, Jose O.,Mendonca-Previato
, p. 321 - 330 (2007/10/03)
We report full 1H and 13C NMR assignments for 13 gluco- or galacto- pyranosylated derivatives of GlcNAc-ol, GalNAc-ol or ManNAc-ol, many of which have been prepared by enzymatic methods. These spectra are reference data to aid the structural analysis by NMR spectroscopy of glycosylated alditols derived from the mucin of the protozoan parasite Trypanosoma cruzi. A series of structural reporter groups for the derivatives from this unusual series of O-glycans are described. (C) 2000 Elsevier Science Ltd.
