8spp

Crystal structure of a heme enzyme RufO in rufomycin biosynthesisCrystal structure of a heme enzyme RufO in rufomycin biosynthesis

Structural highlights 8spp is a 1 chain structure with sequence from Streptomyces atratus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 1.89Å Ligands: Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function A0A224AU14_STRAR Publication Abstract from PubMed Rufomycins constitute a class of cyclic heptapeptides isolated from actinomycetes. They are secondary metabolites that show promising treatment against Mycobacterium tuberculosis infections by inhibiting a novel drug target. Several nonproteinogenic amino acids are integrated into rufomycins, including a conserved 3-nitro-tyrosine. RufO, a cytochrome P450 (CYP)-like enzyme, was proposed to catalyze the formation of 3-nitro-tyrosine in the presence of O(2) and NO. To define its biological function, the interaction between RufO and the proposed substrate tyrosine is investigated using various spectroscopic methods that are sensitive to the structural change of a heme center. However, a low- to high-spin state transition and a dramatic increase in the redox potential that are commonly found in CYPs upon ligand binding have not been observed. Furthermore, a 1.89-A crystal structure of RufO shows that the enzyme has flexible surface regions, a wide-open substrate access tunnel, and the heme center is largely exposed to solvent. Comparison with a closely related nitrating CYP reveals a spacious and hydrophobic distal pocket in RufO, which is incapable of stabilizing a free amino acid. Molecular docking validates the experimental data and proposes a possible substrate. Collectively, our results disfavor tyrosine as the substrate of RufO and point to the possibility that the nitration occurs during or after the assembly of the peptides. This study indicates a new function of the unique nitrating enzyme and provides insights into the biosynthesis of nonribosomal peptides. Structural and spectroscopic characterization of RufO indicates a new biological role in rufomycin biosynthesis.,Jordan S, Li B, Traore E, Wu Y, Usai R, Liu A, Xie ZR, Wang Y J Biol Chem. 2023 Jul 13;299(8):105049. doi: 10.1016/j.jbc.2023.105049. PMID:37451485 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

spinqualitylabelsall models 8spp, resolution 1.89Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image