5bk7 | pdb_00005bk7

The structure of MppP E15A mutant soaked with the substrate L-arginine

spinqualitylabelsall models 5bk7, resolution 2.20Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 5bk7 is a 8 chain structure. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: EQJ Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Publication Abstract from PubMed The PLP-dependent l-arginine hydroxylase/deaminase MppP from Streptomyces wadayamensis (SwMppP) is involved in the biosynthesis of l-enduracididine, a nonproteinogenic amino acid found in several nonribosomally produced peptide antibiotics. SwMppP uses only PLP and molecular oxygen to catalyze a 4-electron oxidation of l-arginine to form a mixture of 2-oxo-4(S)-hydroxy-5-guanidinovaleric acid and 2-oxo-5-guanidinovaleric acid. Steady-state kinetics analysis in the presence and absence of catalase shows that one molecule of peroxide is formed for every molecule of dioxygen consumed in the reaction. Moreover, for each molecule of 2-oxo-4(S)-hydroxy-5-guanidinovaleric acid produced, two molecules of dioxygen are consumed, suggesting that both the 4-hydroxy and 2-keto groups are derived from water. This was confirmed by running the reactions using either ([18])O2 or H2([18])O and analyzing the products by ESI-MS. Incorporation of ([18])O was only observed when the reaction was performed in H2([18])O. Crystal structures of SwMppP with l-arginine, 2-oxo-4(S)-hydroxy-5-guanidinovaleric acid, or 2-oxo-5-guanidinovaleric acid bound were determined at resolutions of 2.2, 1.9. and 1.8 A, respectively. The structural data show that the N-terminal portion of the protein is disordered unless substrate or product is bound in the active site, in which case it forms a well-ordered helix that covers the catalytic center. This observation suggested that the N-terminal helix may have a role in substrate binding and/or catalysis. Our structural and kinetic characterizations of N-terminal variants show that the N-terminus is critical for catalysis. In light of this new information, we have refined our previously proposed mechanism of the SwMppP-catalyzed oxidation of l-arginine. Streptomyces wadayamensis MppP is a PLP-Dependent Oxidase, Not an Oxygenase.,Han L, Vuksanovic N, Oehm SA, Fenske TG, Schwabacher AW, Silvaggi NR Biochemistry. 2018 Mar 6. doi: 10.1021/acs.biochem.8b00130. PMID:29473729 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

Proteopedia Page Contributors and Editors (what is this?)

OCA