Miller Leah M, Chatterjee Champak, van der Donk Wilfred A, Kelleher Neil L
Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
J Am Chem Soc. 2006 Feb 8;128(5):1420-1. doi: 10.1021/ja057203d.
Lacticin 481 synthetase (LctM) is a bifunctional enzyme that undertakes dehydration and cyclization in the structural region of the pre-lacticin peptide (LctA) to introduce three thioether rings and one dehydrobutyrine residue. The order and timing of these events has been investigated employing high-resolution ESI-FTMS-based tandem MS/MS techniques and chemical derivatization. LctM demonstrates highly processive behavior as seen by MS analysis of the reaction course of dehydration. Furthermore, cyclization is not tightly coupled to dehydration and follows at a later stage of the enzymatic reaction.
乳酸链球菌素481合成酶(LctM)是一种双功能酶,它在前体乳酸链球菌素肽(LctA)的结构区域进行脱水和环化反应,以引入三个硫醚环和一个脱氢丁氨酸残基。利用基于高分辨率电喷雾傅里叶变换质谱的串联质谱/质谱技术和化学衍生化方法,对这些反应的顺序和时间进行了研究。通过对脱水反应过程的质谱分析可以看出,LctM表现出高度的持续性。此外,环化反应与脱水反应并非紧密耦合,而是在酶促反应的后期发生。