5ul4

Structure of Cobalamin-dependent S-adenosylmethionine radical enzyme OxsB with aqua-cobalamin and S-adenosylmethionine bound

spinqualitylabelsall models 5ul4, resolution 1.85Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 5ul4 is a 1 chain structure with sequence from Priestia megaterium. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 1.85Å Ligands: EDO, MES, SAM Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function OXSB_PRIMG Isomerase involved in the biosynthesis of oxetanocin A (OXT-A), a nucleoside analog with antitumor, antiviral and antibacterial properties (PubMed:28346939, PubMed:33560833). Catalyzes an oxidative ring contraction of dAMP, forming an oxetane aldehyde (PubMed:28346939, PubMed:33560833). In addition, shows methyltransferase activity in vitro and is able to catalyze the radical mediated, stereoselective C2'-methylation of dAMP to form methylated 2'-dAMP (PubMed:33560833, PubMed:36719327). Also catalyzes the demethylation of S-adenosyl-L-methionine (SAM) to S-adenosyl-L-homocysteine (SAH) (PubMed:33560833). Publication Abstract from PubMed Oxetanocin A (OXT-A) is a potent antitumour, antiviral and antibacterial compound. Biosynthesis of OXT-A has been linked to a plasmid-borne Bacillus megaterium gene cluster that contains four genes: oxsA, oxsB, oxrA and oxrB. Here we show that both the oxsA and oxsB genes are required for the production of OXT-A. Biochemical analysis of the encoded proteins, a cobalamin (Cbl)-dependent S-adenosylmethionine (AdoMet) radical enzyme, OxsB, and an HD-domain phosphohydrolase, OxsA, reveals that OXT-A is derived from a 2'-deoxyadenosine phosphate in an OxsB-catalysed ring contraction reaction initiated by hydrogen atom abstraction from C2'. Hence, OxsB represents the first biochemically characterized non-methylating Cbl-dependent AdoMet radical enzyme. X-ray analysis of OxsB reveals the fold of a Cbl-dependent AdoMet radical enzyme, a family of enzymes with an estimated 7,000 members. Overall, this work provides a framework for understanding the interplay of AdoMet and Cbl cofactors and expands the catalytic repertoire of Cbl-dependent AdoMet radical enzymes. A B12-dependent radical SAM enzyme involved in oxetanocin A biosynthesis.,Bridwell-Rabb J, Zhong A, Sun HG, Drennan CL, Liu HW Nature. 2017 Mar 27. doi: 10.1038/nature21689. PMID:28346939 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

Proteopedia Page Contributors and Editors (what is this?)

OCA