Structural basis for channelling mechanism of a fatty acid beta-oxidation multienzyme complex.

ABSTRACT: The atomic view of the active site coupling termed channelling is a major subject in molecular biology. We have determined two distinct crystal structures of the bacterial multienzyme complex that catalyzes the last three sequential reactions in the fatty acid beta-oxidation cycle. The alpha2beta2 heterotetrameric structure shows the uneven ring architecture, where all the catalytic centers of 2-enoyl-CoA hydratase (ECH), L-3-hydroxyacyl-CoA dehydrogenase (HACD) and 3-ketoacyl-CoA thiolase (KACT) face a large inner solvent region. The substrate, anchored through the 3'-phosphate ADP moiety, allows the fatty acid tail to pivot from the ECH to HACD active sites, and finally to the KACT active site. Coupling with striking domain rearrangements, the incorporation of the tail into the KACT cavi

SUBMITTER: Ishikawa M 

PROVIDER: S-EPMC514956 | biostudies-literature | 2004 Jul

REPOSITORIES: biostudies-literature