Crystal Structure and Mutational Analysis of Isomalto-dextranase, a Member of Glycoside Hydrolase Family 27.

ABSTRACT: Arthrobacter globiformis T6 isomalto-dextranase (AgIMD) is an enzyme that liberates isomaltose from the non-reducing end of a polymer of glucose, dextran. AgIMD is classified as a member of the glycoside hydrolase family (GH) 27, which comprises mainly α-galactosidases and α-N-acetylgalactosaminidases, whereas AgIMD does not show α-galactosidase or α-N-acetylgalactosaminidase activities. Here, we determined the crystal structure of AgIMD. AgIMD consists of the following three domains: A, C, and D. Domains A and C are identified as a (β/α)8-barrel catalytic domain and an antiparallel β-structure, respectively, both of which are commonly found in GH27 enzymes. However, domain A of AgIMD has subdomain B, loop-1, and loop-2, all of which are not found in GH27 human α-galactosidase. AgIMD in a

SUBMITTER: Okazawa Y 

PROVIDER: S-EPMC4646281 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature