Centre for Translational and Chemical Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3JR, UK.
Centre for Translational and Chemical Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3JR, UK.
Biochem Biophys Res Commun. 2014 Jul 25;450(2):936-41. doi: 10.1016/j.bbrc.2014.06.113. Epub 2014 Jun 28.
Three structurally distinct forms of phosphoglycerate mutase from the trypanosomatid parasite Leishmania mexicana were isolated by standard procedures of bacterial expression and purification. Analytical size-exclusion chromatography coupled to a multi-angle scattering detector detected two monomeric forms of differing hydrodynamic radii, as well as a dimeric form. Structural comparisons of holoenzyme and apoenzyme trypanosomatid cofactor-independent phosphoglycerate mutase (iPGAM) X-ray crystal structures show a large conformational change between the open (apoenzyme) and closed (holoenzyme) forms accounting for the different monomer hydrodynamic radii. Until now iPGAM from trypanosomatids was considered to be only monomeric, but results presented here show the appearance of a dimeric form. Taken together, these observations are important for the choice of screening strategies to identify inhibitors of iPGAM for parasite chemotherapy and highlight the need to select the most biologically or functionally relevant form of the purified enzyme.
三种结构不同的磷酸甘油酸变位酶从原生动物寄生虫利什曼原虫被分离出来的细菌表达和纯化的标准程序。分析尺寸排阻色谱法与多角度散射探测器检测两种单体形式的不同流体力学半径，以及二聚体形式。全酶和脱辅基的原生动物因子独立磷酸甘油酸变位酶（iPGAM）X 射线晶体结构的结构比较显示一个大的构象变化之间的开放（脱辅基酶）和封闭（全酶）形式占不同单体流体力学半径。到目前为止，认为 iPGAM 从原生动物只有单体，但这里呈现的结果表明二聚体形式的出现。总的来说，这些观察结果对于筛选策略的选择具有重要意义，以确定寄生虫化疗的 iPGAM 抑制剂，并强调需要选择最相关的生物或功能形式的纯化酶。
