Enzymes
UniProtKB help_outline | 1,879 proteins |
Enzyme class help_outline |
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GO Molecular Function help_outline |
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Reaction participants Show >> << Hide
- Name help_outline D-cellobiose Identifier CHEBI:17057 (Beilstein: 1292744; CAS: 528-50-7) help_outline Charge 0 Formula C12H22O11 InChIKeyhelp_outline GUBGYTABKSRVRQ-CUHNMECISA-N SMILEShelp_outline OC[C@H]1O[C@@H](O[C@@H]2[C@@H](CO)OC(O)[C@H](O)[C@H]2O)[C@H](O)[C@@H](O)[C@@H]1O 2D coordinates Mol file for the small molecule Search links Involved in 7 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline β-D-glucosyl-(1→4)-D-mannopyranose Identifier CHEBI:47931 (Beilstein: 1292742) help_outline Charge 0 Formula C12H22O11 InChIKeyhelp_outline GUBGYTABKSRVRQ-LNCRCTFVSA-N SMILEShelp_outline OC[C@H]1O[C@@H](O[C@@H]2[C@@H](CO)OC(O)[C@@H](O)[C@H]2O)[C@H](O)[C@@H](O)[C@@H]1O 2D coordinates Mol file for the small molecule Search links Involved in 1 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
Cross-references
RHEA:23384 | RHEA:23385 | RHEA:23386 | RHEA:23387 | |
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Reaction direction help_outline | undefined | left-to-right | right-to-left | bidirectional |
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Publications
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Crystal structure of Ruminococcus albus cellobiose 2-epimerase: structural insights into epimerization of unmodified sugar.
Fujiwara T., Saburi W., Inoue S., Mori H., Matsui H., Tanaka I., Yao M.
Enzymatic epimerization is an important modification for carbohydrates to acquire diverse functions attributable to their stereoisomers. Cellobiose 2-epimerase (CE) catalyzes interconversion between d-glucose and d-mannose residues at the reducing end of β-1,4-linked oligosaccharides. Here, we sol ... >> More
Enzymatic epimerization is an important modification for carbohydrates to acquire diverse functions attributable to their stereoisomers. Cellobiose 2-epimerase (CE) catalyzes interconversion between d-glucose and d-mannose residues at the reducing end of β-1,4-linked oligosaccharides. Here, we solved the structure of Ruminococcus albus CE (RaCE). The structure of RaCE showed strong similarity to those of N-acetyl-D-glucosamine 2-epimerase and aldose-ketose isomerase YihS with a high degree of conservation of residues around the catalytic center, although sequence identity between them is low. Based on structural comparison, we found that His184 is required for RaCE activity as the third histidine added to two essential histidines in other sugar epimerases/isomerases. This finding was confirmed by mutagenesis, suggesting a new catalytic mechanism for CE involving three histidines. << Less
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Epimerization of disaccharides by enzyme preparations from Ruminococcus albus.
Tyler T.R., Leatherwood J.M.
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Enzymatic properties of cellobiose 2-epimerase from Ruminococcus albus and the synthesis of rare oligosaccharides by the enzyme.
Ito S., Taguchi H., Hamada S., Kawauchi S., Ito H., Senoura T., Watanabe J., Nishimukai M., Ito S., Matsui H.
The gene for cellobiose 2-epimerase (CE) from Ruminococcus albus NE1 was overexpressed in Escherichia coli cells. The recombinant CE was purified to homogeneity by a simple purification procedure with a high yield of 88%, and the molecular mass was 43.1 kDa on sodium dodecyl sulfate polyacrylamide ... >> More
The gene for cellobiose 2-epimerase (CE) from Ruminococcus albus NE1 was overexpressed in Escherichia coli cells. The recombinant CE was purified to homogeneity by a simple purification procedure with a high yield of 88%, and the molecular mass was 43.1 kDa on sodium dodecyl sulfate polyacrylamide gel electrophoresis and 44.0 kDa on gel chromatography. It exhibited optimal activity around at 30 degrees C and pH 7.5, and the enzyme activity was inhibited by Al3+, Fe3+, Co2+, Cu2+, Zn2+, Pb2+, Ag+, N-bromosuccinimide, iodoacetate, and 4-chloromercuribenzoate. In addition to cello-oligosaccharides, the enzyme was found to effectively 2-epimerize lactose to yield 4-O-beta-D-galactopyranosyl-D-mannose (epilactose), which occurs in cow milk as a rare oligosaccharide. The Km and kcat/Km values toward lactose were 33 mM and 1.6 s(-1) mM(-1), and those toward cellobiose were 13.8 mM and 4.6 s(-1) mM(-1), respectively. N-Acetyl-D-glucosamine, uridine 5'-diphosphate-glucose, D-glucose 6-phosphate, maltose, sophorose, laminaribiose, and gentiobiose were inert as substrates for the recombinant CE. We demonstrated that epilactose was resistant to rat intestinal enzymes, utilized by human adult bifidobacteria, and stimulated the tight junction permeability in Caco-2 cells. These results strongly suggest that this rare disaccharide is promising for use as a prebiotic. << Less
Appl. Microbiol. Biotechnol. 79:433-441(2008) [PubMed] [EuropePMC]