LytB蛋白催化类异戊二烯生物合成的2-C-甲基-D-赤藓糖醇-4-磷酸途径的末端步骤。

LytB protein catalyzes the terminal step of the 2-C-methyl-D-erythritol-4-phosphate pathway of isoprenoid biosynthesis.

作者信息

Altincicek Boran, Duin Evert C, Reichenberg Armin, Hedderich Reiner, Kollas Ann-Kristin, Hintz Martin, Wagner Stefanie, Wiesner Jochen, Beck Ewald, Jomaa Hassan

机构信息

Jomaa Pharmaka GmbH, Frankfurter Strasse 50, 35392, Giessen, Germany.

出版信息

FEBS Lett. 2002 Dec 18;532(3):437-40. doi: 10.1016/s0014-5793(02)03726-2.

DOI:10.1016/s0014-5793(02)03726-2

PMID:12482608

Abstract

Recombinant LytB protein from the thermophilic eubacterium Aquifex aeolicus produced in Escherichia coli was purified to apparent homogeneity. The purified LytB protein catalyzed the reduction of (E)-4-hydroxy-3-methyl-but-2-enyl diphosphate (HMBPP) in a defined in vitro system. The reaction products were identified as isopentenyl diphosphate and dimethylallyl diphosphate. A spectrophotometric assay was established to determine the steady-state kinetic parameters of LytB protein. The maximal specific activity of 6.6+/-0.3 micromol x min(-1) x mg(-1) protein was determined at pH 7.5 and 60 degrees C. The k(cat) value of the LytB protein was 3.7+/-0.2 s(-1) and the K(m) value for HMBPP was 590+/-60 microM.

摘要

从嗜热真细菌嗜水气单胞菌中获得的重组LytB蛋白在大肠杆菌中表达并纯化至表观均一。纯化后的LytB蛋白在特定的体外系统中催化（E）-4-羟基-3-甲基-丁-2-烯基二磷酸（HMBPP）的还原反应。反应产物被鉴定为异戊烯基二磷酸和二甲基烯丙基二磷酸。建立了一种分光光度法来测定LytB蛋白的稳态动力学参数。在pH 7.5和60℃条件下，测定的最大比活性为6.6±0.3微摩尔·分钟⁻¹·毫克⁻¹蛋白。LytB蛋白的k(cat)值为3.7±0.2秒⁻¹，HMBPP的K(m)值为590±60微摩尔。