2University of Turku, Department of Biochemistry, FIN-20014 Turku, Finland; E-mail: email@example.com
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Received June 15, 2017; Revision received July 3, 2017
Cystathionine β-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.
KEY WORDS: cystathionine β-synthase, inosine 5′-monophosphate dehydrogenase, AMP-activated protein kinase, allostery, CBS domain, adenine nucleotides