Rice D W, Yip K S, Stillman T J, Britton K L, Fuentes A, Connerton I, Pasquo A, Scandura R, Engel P C
Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, University of Sheffield, UK.
FEMS Microbiol Rev. 1996 May;18(2-3):105-17. doi: 10.1111/j.1574-6976.1996.tb00230.x.
The structure determination of the glutamate dehydrogenase from the hyperthermophile Pyrococcus furiosus has been completed at 2.2 A resolution. The structure has been compared with the glutamate dehydrogenases from the mesophiles Clostridium symbiosum, Escherichia coli and Neurospora crassa. This comparison has revealed that the hyperthermophilic enzyme contains a striking series of networks of ion-pairs which are formed by regions of the protein which contain a high density of charged residues. Such regions are not found in the mesophilic enzymes and the number and extent of ion-pair formation is much more limited. The ion-pair networks are clustered at both inter domain and inter subunit interfaces and may well represent a major stabilising feature associated with the adaptation of enzymes to extreme temperatures.
嗜热古菌激烈火球菌谷氨酸脱氢酶的结构测定已在2.2埃分辨率下完成。该结构已与嗜温菌共生梭菌、大肠杆菌和粗糙脉孢菌的谷氨酸脱氢酶进行了比较。这种比较表明，嗜热酶含有一系列引人注目的离子对网络，这些离子对由蛋白质中富含带电残基的区域形成。在嗜温酶中未发现此类区域，离子对形成的数量和程度也更为有限。离子对网络聚集在结构域间和亚基间界面处，很可能代表了与酶适应极端温度相关的主要稳定特征。
