Schuldt Linda, Suchowersky Ruth, Veith Katharina, Mueller-Dieckmann Jochen, Weiss Manfred S
EMBL Hamburg Outstation, c/o DESY, Notkestrasse 85, D-22603 Hamburg, Germany.
Acta Crystallogr Sect F Struct Biol Cryst Commun. 2011 Mar 1;67(Pt 3):380-5. doi: 10.1107/S1744309111000030. Epub 2011 Feb 25.
The regulatory domain of Mycobacterium tuberculosis aspartokinase (Mtb-AK, Mtb-Ask, Rv3709c) has been cloned, heterologously expressed in Escherichia coli and purified using standard chromatographic techniques. Screening for initial crystallization conditions using the regulatory domain (AK-β) in the presence of the potential feedback inhibitor threonine identified four conditions which yielded crystals suitable for X-ray diffraction analysis. From these four conditions five different crystal forms of Mtb-AK-β resulted, three of which belonged to the orthorhombic system, one to the tetragonal system and one to the monoclinic system. The highest resolution (1.6 Å) was observed for a crystal form belonging to space group P2(1)2(1)2(1), with unit-cell parameters a=53.70, b=63.43, c=108.85 Å and two molecules per asymmetric unit.
结核分枝杆菌天冬氨酸激酶（Mtb-AK、Mtb-Ask、Rv3709c）的调节结构域已被克隆，在大肠杆菌中进行异源表达，并使用标准色谱技术进行纯化。在存在潜在反馈抑制剂苏氨酸的情况下，使用调节结构域（AK-β）筛选初始结晶条件，确定了四种能产生适合X射线衍射分析的晶体的条件。从这四种条件下得到了Mtb-AK-β的五种不同晶体形式，其中三种属于正交晶系，一种属于四方晶系，一种属于单斜晶系。对于属于空间群P2(1)2(1)2(1)的晶体形式，观察到最高分辨率（1.6 Å），其晶胞参数a=53.70、b=63.43、c=108.85 Å，每个不对称单元中有两个分子。
