4-O-β-吡喃半乳糖-D-甘露糖是一种用于生物材料或有机化合物研究的生物化学试剂,在生命科学研究中也有广泛应用。
中文名称 | 英文名称 | CAS号 | 化学式 | 分子量 |
---|---|---|---|---|
乳糖 | D-(+)-lactose | 63-42-3 | C12H22O11 | 342.3 |
β-乳糖 | LACTOSE | 5965-66-2 | C12H22O11 | 342.3 |
D-(+)-纤维二糖 | Maltose | 133-99-3 | C12H22O11 | 342.3 |
—— | Cellobiose | 13360-52-6 | C12H22O11 | 342.3 |
—— | Lactose | 63-42-3 | C12H22O11 | 342.3 |
直链淀粉 | maltotriose | 9005-82-7 | C18H32O16 | 504.442 |
中文名称 | 英文名称 | CAS号 | 化学式 | 分子量 |
---|---|---|---|---|
—— | Lactose | 63-42-3 | C12H22O11 | 342.3 |
The aerobic soil bacterium Cellvibrio vulgaris has a β-mannan-degradation gene cluster, including unkA, epiA, man5A, and aga27A. Among these genes, epiA has been assigned to encode an epimerase for converting d-mannose to d-glucose, even though the amino acid sequence of EpiA is similar to that of cellobiose 2-epimerases (CEs). UnkA, whose function currently remains unknown, shows a high sequence identity to 4-O-β-d-mannosyl-d-glucose phosphorylase. In this study, we have investigated CE activity of EpiA and the general characteristics of UnkA using recombinant proteins from Escherichia coli. Recombinant EpiA catalyzed the epimerization of the 2-OH group of sugar residue at the reducing end of cellobiose, lactose, and β-(1→4)-mannobiose in a similar manner to other CEs. Furthermore, the reaction efficiency of EpiA for β-(1→4)-mannobiose was 5.5 × 104-fold higher than it was for d-mannose. Recombinant UnkA phosphorolyzed β-d-mannosyl-(1→4)-d-glucose and specifically utilized d-glucose as an acceptor in the reverse reaction, which indicated that UnkA is a typical 4-O-β-d-mannosyl-d-glucose phosphorylase.