Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:4.2.1.22 (cystathionine beta-synthase)
 965 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Conserved pairs of CBS sequence motifs (named after cystathionine beta-synthase) found in a wide variety of proteins associate to form Bateman domains. A new study establishes that Bateman domains bind adenosyl compounds and regulate IMP dehydrogenase, CBS, chloride channels, and AMP-activated protein kinase. This discovery reveals how mutations in CBS sequences in these proteins cause hereditary diseases and provides a rich vista of conceptual opportunities for therapies in energy metabolism, obesity, diabetes, cancer, antivirals, and immunosuppression.
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PMID:Bateman domains and adenosine derivatives form a binding contract. 1472 19

AMP-activated protein kinase (AMPK) is a central regulator of energy homeostasis in mammals. AMP is believed to control the activity of AMPK by binding to the gamma subunit of this heterotrimeric enzyme. This subunit contains two Bateman domains, each of which is composed of a tandem pair of cystathionine beta-synthase (CBS) motifs. No structural information is currently available on this subunit, and the molecular basis for its interactions with AMP is not well understood. We report here the crystal structure at 1.9 Angstrom resolution of the Bateman2 domain of Snf4, the gamma subunit of the yeast ortholog of AMPK. The structure revealed a dimer of the Bateman2 domain, and this dimerization is supported by our light-scattering, mutagenesis, and biochemical studies. There is a prominent pocket at the center of this dimer, and most of the disease-causing mutations are located in or near this pocket.
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PMID:Structure of the Bateman2 domain of yeast Snf4: dimeric association and relevance for AMP binding. 1722 33

Mammalian AMP-activated protein kinase is a serine/threonine protein kinase that acts as a sensor of cellular energy status. AMP-activated protein kinase is a heterotrimer of three different subunits, i.e. alpha, beta, and gamma, with alpha being the catalytic subunit and beta and gamma having regulatory roles. Although several studies have defined different domains in alpha and beta involved in the interaction with the other subunits of the complex, little is known about the regions of the gamma subunits involved in these interactions. To study this, we have made sequential deletions from the N termini of the gamma subunit isoforms and studied the interactions with alpha and beta subunits, both by two-hybrid analysis and by co-immunoprecipitation. Our results suggest that a conserved region of 20-25 amino acids in gamma1, gamma2, and gamma3, immediately N-terminal to the Bateman domains, is required for the formation of a functional, active alphabetagamma complex. This region is required for the interaction with the beta subunits. The interaction between the alpha and gamma subunits does not require this region and occurs instead within the Bateman domains of the gamma subunit, although the alpha-gamma interaction does appear to stabilize the beta-gamma interaction. In addition, sequential deletions from the C termini of the gamma subunits indicate that deletion of any of the CBS (cystathionine beta-synthase) motifs prevents the formation of a functional complex with the alpha and beta subunits.
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PMID:A conserved sequence immediately N-terminal to the Bateman domains in AMP-activated protein kinase gamma subunits is required for the interaction with the beta subunits. 1740 75

Cystathionine beta-synthase (CBS) domains are small motifs that are present in proteins with completely different functions. Several genetic diseases in humans have been associated with mutations in their sequence, which has made them promising targets for rational drug design. The protein MJ0100 from Methanocaldococcus jannaschii includes a DUF39 domain of so far unknown function and a CBS domain pair (Bateman domain) at its C-terminus. This work presents the crystallographic analysis of four different states of the CBS motif pair of MJ0100 in complex with different numbers of S-adenosyl-L-methionine (SAM) and S-methyl-5'-thioadenosine (MTA) ligands, providing evidence that ligand-induced conformational reorganization of Bateman domain dimers could be an important regulatory mechanism. These observations are in contrast to what is known from most of the other Bateman domain structures but are supported by recent studies on the magnesium transporter MgtE. Our structures represent the first example of a CBS domain protein complexed with SAM and/or MTA and might provide a structural basis for understanding the molecular mechanisms regulated by SAM upon binding to the C-terminal domain of human CBS, whose structure remains unknown.
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PMID:Binding of S-methyl-5'-thioadenosine and S-adenosyl-L-methionine to protein MJ0100 triggers an open-to-closed conformational change in its CBS motif pair. 2002 78

In mammals, 5'-AMP-activated protein kinase (AMPK) is a heterotrimeric protein composed of a catalytic serine/threonine kinase subunit (alpha) and two regulatory subunits (beta and gamma). The gamma-subunit senses the intracellular energy status by competitively binding AMP and ATP and is thought to be responsible for allosteric regulation of the whole complex. We describe herein the crystal structure of protein MJ1225 from Methanocaldococcus jannaschii complexed to AMP, ADP, and ATP. Our data provide evidence of a strong conservation of the key functional features seen in the gamma-subunit of the eukaryotic AMPK, and more importantly, it reveals a novel AMP binding site, herein denoted as site E, which had not been previously described in cystathionine beta-synthase domains so far. Site E is located in a small cavity existing between the alpha-helices structurally equivalent to those disrupting the internal symmetry of each Bateman domain in gamma-AMPKs and shows striking similarities with a symmetry-related crevice of the mammalian enzyme that hosts the pathological mutation N488I.
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PMID:The crystal structure of protein MJ1225 from Methanocaldococcus jannaschii shows strong conservation of key structural features seen in the eukaryal gamma-AMPK. 2038 58