Nessler S, Le Bras G, Le Bras G, Garel J R
Laboratoire de Biologie Structurale, UMR 9920 CNRS-Université Paris-Sud, Orsay, France.
J Mol Biol. 1994 Jan 7;235(1):370-1. doi: 10.1016/s0022-2836(05)80043-9.
The D-lactate dehydrogenase (D-LDH) from Lactobacillus bulgaricus has been purified and co-crystallized with its cofactor NAD+. Crystals suitable for X-ray diffraction experiments have been obtained from an ammonium sulfate solution by the hanging-drop method. The crystals belong to the orthorhombic space group C222 (or C222(1)) with cell dimensions a = 76.5 A, b = 93.3 A, c = 118.4 A and one monomer of 37,000 daltons per asymmetric unit. They diffract beyond 3.0 A resolution. Sequence comparison suggests that D-LDHs have no evolutionary relationship to L-LDHs and belong instead to the family of the D-2-hydroxyacid dehydrogenases. The X-ray crystallographic structure of the D-LDH from Lactobacillus bulgaricus will be a decisive test of this hypothesis.
保加利亚乳杆菌的D-乳酸脱氢酶（D-LDH）已被纯化，并与辅因子NAD+共结晶。通过悬滴法从硫酸铵溶液中获得了适合X射线衍射实验的晶体。这些晶体属于正交晶系空间群C222（或C222(1)），晶胞参数a = 76.5 Å，b = 93.3 Å，c = 118.4 Å，每个不对称单元有一个37,000道尔顿的单体。它们的衍射分辨率超过3.0 Å。序列比较表明，D-LDH与L-LDH没有进化关系，而是属于D-2-羟基酸脱氢酶家族。保加利亚乳杆菌D-LDH的X射线晶体结构将对这一假设进行决定性检验。
