Cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of the regulatory domain of aspartokinase (Rv3709c) from Mycobacterium tuberculosis.

ABSTRACT: 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-?) 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-? 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.

SUBMITTER: Schuldt L 

PROVIDER: S-EPMC3053168 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature