Mayer Suzanne M, Gormal Carol A, Smith Barry E, Lawson David M
Department of Biological Chemistry, John Innes Centre, Norwich NR4 7UH, United Kingdom.
J Biol Chem. 2002 Sep 20;277(38):35263-6. doi: 10.1074/jbc.M205888200. Epub 2002 Jul 19.
The x-ray crystal structure of NifV(-) Klebsiella pneumoniae nitrogenase MoFe protein (NifV(-) Kp1) has been determined and refined to a resolution of 1.9 A. This is the first structure for a nitrogenase MoFe protein with an altered cofactor. Moreover, it is the first direct evidence that the organic acid citrate is not just present, but replaces homocitrate as a ligand to the molybdenum atom of the iron molybdenum cofactor (FeMoco). Subsequent refinement of the structure revealed that the citrate was present at reduced occupancy.
肺炎克雷伯氏菌固氮酶钼铁蛋白(NifV(-) Kp1)的X射线晶体结构已被测定并精修至1.9埃的分辨率。这是具有改变辅因子的固氮酶钼铁蛋白的首个结构。此外,这是首个直接证据,表明有机酸柠檬酸盐不仅存在,而且取代高柠檬酸作为铁钼辅因子(FeMoco)中钼原子的配体。随后对该结构的精修显示,柠檬酸盐的占有率降低。