Structural basis of regulation and oligomerization of human cystathionine β-synthase, the central enzyme of transsulfuration.

ABSTRACT: Cystathionine β-synthase (CBS) controls the flux of sulfur from methionine to cysteine, a precursor of glutathione, taurine, and H2S. CBS condenses serine and homocysteine to cystathionine with the help of three cofactors, heme, pyridoxal-5'-phosphate, and S-adenosyl-l-methionine. Inherited deficiency of CBS activity causes homocystinuria, the most frequent disorder of sulfur metabolism. We present the structure of the human enzyme, discuss the unique arrangement of the CBS domains in the C-terminal region, and propose how they interact with the catalytic core of the complementary subunit to regulate access to the catalytic site. This arrangement clearly contrasts with other proteins containing the CBS domain including the recent Drosophila melanogaster CBS structure. The absence of large

SUBMITTER: Ereno-Orbea J 

PROVIDER: S-EPMC3791738 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature