Crystal structure of LAAO from Calloselasma rhodostoma with an L-phenylalanine substrate: insights into structure and mechanism.

ABSTRACT: L-Amino acid oxidase is a dimeric glycosylated flavoenzyme, a major constituent of the venom-from the snake Calloselasma rhodostoma. The enzyme exhibits apoptosis inducing effects as well as antibacterial and anti-HIV activities. The structure of l-amino acid oxidase with its substrate (L-phenylalanine) has been refined to a resolution of 1.8 A. The complex structure reveals the substrate bound to the reduced flavin (FADred). Alternative conformations for the key residues His223 and Arg322 are evident, suggesting a dynamic active site. Furthermore, conformational changes are apparent for the isoalloxazine ring; the three-ring system exhibits more bending around the N5-N10 axis compared to the oxidized flavin. The implications of the observed dynamics on the mechanism of catalysis are discu

SUBMITTER: Moustafa IM 

PROVIDER: S-EPMC2018609 | biostudies-literature | 2006 Dec

REPOSITORIES: biostudies-literature