Read Jay A, Walsh Christopher T
Harvard Medical School, Department of Biological Chemistry and Molecular Pharmacology, 240 Longwood Avenue Boston, Massachusetts 02115, USA.
J Am Chem Soc. 2007 Dec 26;129(51):15762-3. doi: 10.1021/ja077374d. Epub 2007 Nov 29.
In comparison with the large number of nonribosomal peptide synthetases (NRPSs) that release their peptide products by hydrolytic cleavage of the peptide carrier protein (PCP) bound thioester, there are relatively few NRPSs that have been shown to use a nicotinamide cofactor to reduce this PCP-peptidyl thioester to an aldehyde or imine moiety. This work describes the first example of a reductase domain within a NRPS scaffold shown to reduce a PCP-peptidyl thioester to the corresponding primary alcohol, via an aldehyde intermediate, using two equivalents of reduced nicotinamide adenine dinucleotide phosphate (NADPH). By employing a ketone mimic of the aldehyde intermediate, as well as a specifically deuterated NADPH, it was further demonstrated that the pro-S hydride of the cofactor is transferred to the re face of the carbonyl group.
与大量通过水解切割与肽载体蛋白（PCP）结合的硫酯来释放其肽产物的非核糖体肽合成酶（NRPS）相比，已显示使用烟酰胺辅因子将这种PCP-肽基硫酯还原为醛或亚胺部分的NRPS相对较少。这项工作描述了NRPS支架内还原酶结构域的首个实例，该结构域通过醛中间体，使用两当量的还原型烟酰胺腺嘌呤二核苷酸磷酸（NADPH），将PCP-肽基硫酯还原为相应的伯醇。通过使用醛中间体的酮模拟物以及特异性氘代的NADPH，进一步证明辅因子的前-S氢化物转移到羰基的Re面。
