Roberts A, Gill R, Hussey R J, Mikolajek H, Erskine P T, Cooper J B, Wood S P, Chrystal E J T, Shoolingin-Jordan P M
School of Biological Sciences, University of Southampton, Southampton SO16 7PX, England.
Acta Crystallogr Sect F Struct Biol Cryst Commun. 2012 Dec 1;68(Pt 12):1491-3. doi: 10.1107/S1744309112042212. Epub 2012 Nov 14.
The enzyme porphobilinogen deaminase (PBGD; hydroxymethylbilane synthase; EC 2.5.1.61) catalyses a key early step of the haem-biosynthesis pathway in which four molecules of the monopyrrole porphobilinogen are condensed to form a linear tetrapyrrole. The enzyme possesses a dipyrromethane cofactor which is covalently linked by a thioether bridge to an invariant cysteine residue. Since PBGD catalyses a reaction which is common to the biosynthesis of both haem and chlorophyll, structural studies of a plant PBGD enzyme offer great potential for the discovery of novel herbicides. Until recently, structural data have only been available for the Escherichia coli and human forms of the enzyme. Expression in E. coli of a codon-optimized gene for Arabidopsis thaliana PBGD has permitted for the first time the crystallization and preliminary X-ray analysis of the enzyme from a plant species at high resolution.
胆色素原脱氨酶（PBGD；羟甲基胆色素原合酶；EC 2.5.1.61）催化血红素生物合成途径中一个关键的早期步骤，在此步骤中，四个单吡咯胆色素原分子缩合形成一个线性四吡咯。该酶具有一个二吡咯甲烷辅因子，它通过硫醚桥与一个不变的半胱氨酸残基共价连接。由于PBGD催化的反应是血红素和叶绿素生物合成共有的，因此对植物PBGD酶的结构研究为发现新型除草剂提供了巨大潜力。直到最近，仅获得了大肠杆菌和人类形式该酶的结构数据。对拟南芥PBGD的密码子优化基因在大肠杆菌中的表达首次实现了对来自植物物种的该酶进行高分辨率结晶和初步X射线分析。
