Bent Andrew F, Koehnke Jesko, Houssen Wael E, Smith Margaret C M, Jaspars Marcel, Naismith James H
Biomedical Sciences Research Complex, University of St Andrews, North Haugh, St Andrews, Fife KY16 9ST, Scotland.
Acta Crystallogr Sect F Struct Biol Cryst Commun. 2013 Jun;69(Pt 6):618-23. doi: 10.1107/S1744309113012931. Epub 2013 May 23.
Patellamides are macrocyclic peptides with potent biological effects and are a subset of the cyanobactins. Cyanobactins are natural products that are produced by a series of enzymatic transformations and a common modification is the addition of a prenyl group. Puzzlingly, the pathway for patellamides in Prochloron didemni contains a gene, patF, with homology to prenylases, but patellamides are not themselves prenylated. The structure of the protein PatF was cloned, expressed, purified and determined. Prenylase activity could not be demonstrated for the protein, and examination of the structure revealed changes in side-chain identity at the active site. It is suggested that these changes have inactivated the protein. Attempts to mutate these residues led to unfolded protein.
海鞘酰胺是具有强大生物效应的大环肽，是蓝细菌素的一个子集。蓝细菌素是通过一系列酶促转化产生的天然产物，常见的修饰是添加一个异戊烯基。令人费解的是，迪氏原绿藻中海鞘酰胺的合成途径包含一个与异戊烯基转移酶具有同源性的基因patF，但海鞘酰胺本身并未发生异戊烯基化。对蛋白质PatF的结构进行了克隆、表达、纯化和测定。未证明该蛋白质具有异戊烯基转移酶活性，对其结构的研究揭示了活性位点侧链一致性的变化。有人认为这些变化使该蛋白质失活。对这些残基进行突变的尝试导致蛋白质无法折叠。
