Enzymes Regulated via Cystathionine [beta]-Synthase Domains

Cystathionine [beta]-Synthase (CBS) domains discovered 20 years ago can bind different adenosine derivatives (AMP, ADP, ATP, S-adenosylmethionine, NAD, diadenosine polyphosphates) and thus regulate the activities of numerous proteins. Mutations in CBS domains of enzymes and membrane transporters are associated with several hereditary diseases. The regulatory unit is a quartet of CBS domains that belong to one or two polypeptides and usually form a conserved disk-like structure. CBS domains function as "internal inhibitors" in enzymes, and their bound ligands either amplify or attenuate the inhibitory effect. Recent studies have opened a way to understanding the structural basis of enzyme regulation via CBS domains and widened the list of their bound ligands. DOI: 10.1134/S0006297917100017 Keywords: cystathionine [beta]-Synthase, inosine 5'-monophosphate dehydrogenase, AMP-activated protein kinase, allostery, CBS domain, adenine nucleotides