Structural fine-tuning of a multifunctional cytochrome p450 monooxygenase.

摘要: AurH is a unique cytochrome P450 monooxygenase catalyzing the stepwise formation of homochiral oxygen heterocycle, key structural and pharmacophoric component antibiotic aureothin. The exceptional enzymatic reaction involves tandem oxygenation process including regio- stereospecific hydroxylation, followed by heterocyclization. For biochemical basis this unparalleled sequence, four crystal structures variants in different conformational states complex with inhibitor ancymidol were solved, which represent first CYP151A group. Structural data conjunction computational docking, site-directed mutagenesis, chemical analyses unveiled switch function when recognizing two substrates, deoxyaureothin hydroxylated intermediate, thus allowing second oxygenation-heterocyclization step. Furthermore, we able to modify chemo- regioselectivity AurH, yielding mutants that catalyze regioselective six-electron transfer nonactivated methyl group carboxylic acid via hydroxyl aldehyde intermediates.