Crystallization and preliminary X-ray diffraction analysis of the high molecular weight ketoacyl reductase FabG4 complexed with NADH.

Department of Biotechnology, Indian Institute of Technology, Kharagpur, Kharagpur 721 302, India.
Acta Crystallographica Section F Structural Biology and Crystallization Communications (Impact Factor: 0.55). 07/2012; 68(Pt 7):786-9. DOI: 10.1107/S1744309112020301
Source: PubMed

ABSTRACT FabG4 from Mycobacterium tuberculosis belongs to the high molecular weight ketoacyl reductases (HMwFabGs). The enzyme requires NADH for β-ketoacyl reductase activity. The protein was overexpressed, purified to homogeneity and crystallized as a FabG4-NADH complex. A mountable FabG4:NADH complex crystal diffracted to 2.59 Å resolution and belonged to space group P1, with unit-cell parameters a = 63.07, b = 71.03, c = 92.92 Å, α = 105.02, β = 97.06, γ = 93.66°. The Matthews coefficient suggested the presence of four monomers in the unit cell. In addition, a self-rotation function revealed the presence of two twofold NCS axes and one fourfold NCS axis. At χ = 180° the highest peak corresponds to the twofold NCS between two monomers, whereas the second peak corresponds to the twofold NCS between two dimers.

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