Substrate Promiscuity of N-Acetylhexosamine 1-Kinases

Molecules

Yanhong Li¹  Hai Yu¹  Yi Chen¹  Kam Lau¹  Li Cai¹  Hongzhi Cao¹  Vinod Kumar Tiwari¹  Jingyao Qu¹  Vireak Thon¹  Peng George Wang¹ 

[1] ¹Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA

关键词: N-acetylgalactosamine;    N-acetylglucosamine;    N-acetylhexosamine 1-kinase;    mannose;    substrate specificity;   

DOI  :  10.3390/molecules16086396

来源: mdpi

【 摘 要 】

N-Acetylhexosamine 1-kinase (NahK) catalyzes the direct addition of a phosphate from adenosine 5'-triphosphate (ATP) to the anomeric position of N-acetylhexosamine and shows similar activity towards N-acetylglucosamine (GlcNAc) and N-acetylgalactosamine (GalNAc). Herein we report the cloning, characterization, and substrate specificity studies of two NahKs from Bifidobacterium infantis ATCC15697 and Bifidobacterium longum ATCC55813, respectively. A new capillary electrophoresis assay method has been developed for enzyme activity assays. Both enzymes have a good expression level in E. coli (180–185 mg/L culture) and can tolerate diverse modifications at C2 of GlcNAc and GalNAc. Various GlcNAc derivatives with C6, both C2 and C6, as well as both C2 and C3 modifications are tolerable substrates for the newly cloned NahKs. Quite interestingly, despite of their low activities toward glucose and galactose, the activities of both NahKs are much higher for mannose and some of its C2, C4, and C6 derivatives. These NahKs are excellent catalysts for enzymatic and chemoenzymatic synthesis of carbohydrates.

【 授权许可】

CC BY   
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