Wubben Jacinta M, Dogovski Con, Dobson Renwick C J, Codd Rachel, Gerrard Juliet A, Parker Michael W, Perugini Matthew A
Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria 3010, Australia.
Acta Crystallogr Sect F Struct Biol Cryst Commun. 2010 Nov 1;66(Pt 11):1511-6. doi: 10.1107/S1744309110036791. Epub 2010 Oct 29.
Dihydrodipicolinate synthase (DHDPS) is an oligomeric enzyme that catalyzes the first committed step of the lysine-biosynthesis pathway in plants and bacteria, which yields essential building blocks for cell-wall and protein synthesis. DHDPS is therefore of interest to drug-discovery research as well as to studies that probe the importance of quaternary structure to protein function, stability and dynamics. Accordingly, DHDPS from the psychrophilic (cold-dwelling) organism Shewanella benthica (Sb-DHDPS) was cloned, expressed, purified and crystallized. The best crystals of Sb-DHDPS were grown in 200 mM ammonium sulfate, 100 mM bis-tris pH 5.0-6.0, 23-26%(w/v) PEG 3350, 0.02%(w/v) sodium azide and diffracted to beyond 2.5 Å resolution. Processing of diffraction data to 2.5 Å resolution resulted in a unit cell with space group P2(1)2(1)2(1) and dimensions a = 73.1, b = 84.0, c = 143.7 Å. These studies of the first DHDPS enzyme to be characterized from a bacterial psychrophile will provide insight into the molecular evolution of enzyme structure and dynamics.
二氢二吡啶酸合酶（DHDPS）是一种寡聚酶，催化植物和细菌中赖氨酸生物合成途径的首个关键步骤，该步骤产生细胞壁和蛋白质合成所需的基本构件。因此，DHDPS对于药物研发研究以及探究四级结构对蛋白质功能、稳定性和动力学的重要性的研究都具有重要意义。相应地，来自嗜冷（栖居于寒冷环境）生物嗜压希瓦氏菌（Sb-DHDPS）的DHDPS被克隆、表达、纯化并结晶。Sb-DHDPS的最佳晶体在含有200 mM硫酸铵、100 mM二（2-羟乙基）氨基三（羟甲基）甲烷pH 5.0 - 6.0、23 - 26%（w/v）聚乙二醇3350、0.02%（w/v）叠氮化钠的溶液中生长，并衍射至2.5 Å以上分辨率。将衍射数据处理至2.5 Å分辨率得到一个空间群为P2(1)2(1)2(1)的晶胞，其尺寸为a = 73.1、b = 84.0、c = 143.7 Å。这些对首个从嗜冷细菌中鉴定出的DHDPS酶的研究将为酶结构和动力学的分子进化提供深入见解。
