2c81
From Proteopedia
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CRYSTAL STRUCTURES OF THE PLP- AND PMP-BOUND FORMS OF BTRR, A DUAL FUNCTIONAL AMINOTRANSFERASE INVOLVED IN BUTIROSIN BIOSYNTHESIS.
Overview
The aminotransferase (BtrR), which is involved in the biosynthesis of, butirosin, a 2-deoxystreptamine (2-DOS)-containing aminoglycoside, antibiotic produced by Bacillus circulans, catalyses the pyridoxal, phosphate (PLP)-dependent transamination reaction both of, 2-deoxy-scyllo-inosose to 2-deoxy-scyllo-inosamine and of, amino-dideoxy-scyllo-inosose to 2-DOS. The high-resolution crystal, structures of the PLP- and PMP-bound forms of BtrR aminotransferase from, B. circulans were solved at resolutions of 2.1 A and 1.7 A with, R(factor)/R(free) values of 17.4/20.6 and 19.9/21.9, respectively. BtrR, has a fold characteristic of the aspartate aminotransferase family, and, sequence and structure analysis categorises it as a member of SMAT, (secondary metabolite aminotransferases) subfamily. It exists as a, homodimer with two active sites per dimer. The active site of the BtrR, protomer is located in a cleft between an alpha helical N-terminus, a, central alphabetaalpha sandwich domain and an alphabeta C-terminal domain., The structures of the PLP- and PMP-bound enzymes are very similar; however, BtrR-PMP lacks the covalent bond to Lys192. Furthermore, the two forms, differ in the side-chain conformations of Trp92, Asp163, and Tyr342 that, are likely to be important in substrate selectivity and substrate binding., This is the first three-dimensional structure of an enzyme from the, butirosin biosynthesis gene cluster.
About this Structure
2C81 is a Single protein structure of sequence from Bacillus circulans with PMP as ligand. Known structural/functional Site: . Full crystallographic information is available from OCA.
Reference
Crystal structures of the PLP- and PMP-bound forms of BtrR, a dual functional aminotransferase involved in butirosin biosynthesis., Popovic B, Tang X, Chirgadze DY, Huang F, Blundell TL, Spencer JB, Proteins. 2006 Oct 1;65(1):220-30. PMID:16894611
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