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1jbq
From Proteopedia
STRUCTURE OF HUMAN CYSTATHIONINE BETA-SYNTHASE: A UNIQUE PYRIDOXAL 5'-PHOSPHATE DEPENDENT HEMEPROTEIN
Overview
Cystathionine beta-synthase (CBS) is a unique heme- containing enzyme that catalyzes a pyridoxal 5'-phosphate (PLP)-dependent condensation of serine and homocysteine to give cystathionine. Deficiency of CBS leads to homocystinuria, an inherited disease of sulfur metabolism characterized by increased levels of the toxic metabolite homocysteine. Here we present the X-ray crystal structure of a truncated form of the enzyme. CBS shares the same fold with O-acetylserine sulfhydrylase but it contains an additional N-terminal heme binding site. This heme binding motif together with a spatially adjacent oxidoreductase active site motif could explain the regulation of its enzyme activity by redox changes.
About this Structure
1JBQ is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Structure of human cystathionine beta-synthase: a unique pyridoxal 5'-phosphate-dependent heme protein., Meier M, Janosik M, Kery V, Kraus JP, Burkhard P, EMBO J. 2001 Aug 1;20(15):3910-6. PMID:11483494 Page seeded by OCA on Fri May 2 21:01:37 2008
