4tpn

High-resolution structure of TxtE in the absence of substrateHigh-resolution structure of TxtE in the absence of substrate

Structural highlights 4tpn is a 1 chain structure with sequence from Streptomyces scabiei 87.22. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 1.18Å Ligands: , , , Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function C9ZDC6_STRSW Publication Abstract from PubMed A novel cytochrome P450 enzyme, TxtE, was recently shown to catalyze the direct aromatic nitration of L-tryptophan. This unique chemistry inspired us to ask whether TxtE could serve as a platform for engineering new nitration biocatalysts to replace current harsh synthetic methods. As a first step toward this goal, and to better understand the wild-type enzyme, we obtained high-resolution structures of TxtE in its substrate-free and substrate-bound forms. We also screened a library of substrate analogues for spectroscopic indicators of binding and for production of nitrated products. From these results, we found that the wild-type enzyme accepts moderate decoration of the indole ring, but the amino acid moiety is crucial for binding and correct positioning of the substrate and therefore less amenable to modification. A nitrogen atom is essential for catalysis, and a carbonyl must be present to recruit the alphaB'1 helix of the protein to seal the binding pocket. Structural, Functional, and Spectroscopic Characterization of the Substrate Scope of the Novel Nitrating Cytochrome P450 TxtE.,Dodani SC, Cahn JK, Heinisch T, Brinkmann-Chen S, McIntosh JA, Arnold FH Chembiochem. 2014 Sep 2. doi: 10.1002/cbic.201402241. PMID:25182183 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

spinqualitylabelsall models 4tpn, resolution 1.18Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image