Open AccessCloning, expression, purification, crystallization and preliminary crystallographic analysis of NifH1 from Methanocaldococcus jannaschii
Author(s) -
Wu Hao,
Yuan Ye,
Ma Jinming,
Gao Yongxiang
Publication year - 2011
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309111007408
Subject(s) - heterotetramer , nitrogenase , azotobacter vinelandii , crystallography , protein subunit , biology , archaea , biochemistry , nitrogen fixation , chemistry , stereochemistry , genetics , bacteria , gene
Nitrogen fixation is catalyzed by the nitrogenase complex in Azotobacter , which is composed of dinitrogenase and dinitrogenase reductase. Dinitrogenase is an α 2 β 2 heterotetramer of the proteins NifD and NifK. Dinitrogenase reductase is a homodimer of the protein NifH. The expression of NifD/K and NifH nitrogenase homologues (named NflD/K and NflH for Nif‐like D and H, respectively) has been detected in the non‐nitrogen‐fixing hyperthermophilic methanogen Methanocaldococcus jannaschii . Solving the structure of Mj NifH1 may help in better understanding its function and may supply some clues to understanding the evolution of nitrogenase. The full‐length protein with an additional His 6 tag at the C‐terminus was expressed, purified and crystallized by the hanging‐drop vapour‐diffusion method at 287 K. An X‐ray diffraction data set was collected to a resolution of 3.3 Å. The crystal belonged to space group P 4 1 32, with unit‐cell parameters a = b = c = 139.45 Å, and was estimated to contain one protein molecule per asymmetric unit.