Structural insight into unique properties of protoporphyrinogen oxidase from Bacillus subtilis

被引：57

作者：

Qin, Xiaohong ^{[2
]}

Sun, Lu ^{[1
]}

Wen, Xin ^{[1
]}

Yang, Xue ^{[2
]}

Tan, Ying ^{[1
]}

Jin, Hao ^{[2
]}

Cao, Qiongyao ^{[1
]}

Zhou, Weihong ^{[2
]}

Xi, Zhen ^{[1
]}

Shen, Yuequan ^{[2
]}

机构：

[1] Nankai Univ, Coll Chem, Dept Biol Chem, State Key Lab Elementoorgan Chem, Tianjin 300071, Peoples R China

[2] Nankai Univ, Coll Life Sci, Tianjin Key Lab Prot Sci, Tianjin 300071, Peoples R China

来源：

JOURNAL OF STRUCTURAL BIOLOGY | 2010年 / 170卷 / 01期

关键词：

Protoporphyrinogen IX oxidase; Tetrapyrrole biosynthesis; BsPPO; Acifluorfen; Variegate porphyria; DIPHENYL ETHER HERBICIDES; VARIEGATE PORPHYRIA; IX OXIDASE; ENZYMIC CONVERSION; CRYSTAL-STRUCTURE; MOLECULAR TARGET; HEME; BIOSYNTHESIS; PURIFICATION; CHLOROPHYLL;

D O I：

10.1016/j.jsb.2009.11.012

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

Protoporphyrinogen IX oxidase (PPO) converts protoporphyrinogen IX to protoporphyrin IX, playing an important part in the heme/chlorophyll biosynthetic pathway. Bacillus subtilis PPO (bsPPO) is unique among PPO family members in that it is a soluble monomer, is inefficiently inhibited by the herbicide acifluorfen (AF) and has broader substrate specificity than other PPO enzymes. Here, we present the crystal structure of bsPPO bound to AF. Our structure shows that the AF molecule binds to a new site outside the previously identified inhibitor binding pocket. Most importantly, the benzene ring of the 2-nitrobenzoic acid moiety of AF lies parallel to the isoalloxazine ring of FAD at a distance of less than 3.5 angstrom, providing a framework for the interaction of FAD with the substrate protoporphyrinogen IX. Furthermore, our structure reveals that the larger substrate binding chamber and predominantly positively charged chamber surface of bsPPO are more favorable or the binding of coproporphyrinogen-III. These crystallographic findings uncover biochemically unique properties of bsPPO, providing important information for further understanding the enzymatic mechanism. (C) 2009 Elsevier Inc. All rights reserved.

引用

页码：76 / 82

页数：7