Insights into the molecular basis of thermal stability from the structure determination of Pyrococcus furiosus gluatamate dehydrogenase

• Published in: FEMS microbiology reviews 1996-05, Vol.18 (2-3), p.105-117
• Main Authors: Rice, D.W., Yip, K.S.P., Stillman, T.J., Britton, K.L., Fuentes, A., Connerton, I., Pasquo, A., Scandurra, R., Engel, P.C.
• Format: Article
• Language: English
• Subjects: Archaea; Bacteria; Dehydrogenase; Dehydrogenases; E coli; Enzymes; Glutamate dehydrogenase; Hyperthermophile; Interfaces; Ion‐pair network; Mesophiles; Neurospora; Pair bond; Pyrococcus furiosus; Structural stability; Thermal stability; X‐ray crystallography
• ISSN: 0168-6445; 1574-6976; 1574-6976
• DOI: 10.1111/j.1574-6976.1996.tb00230.x

Abstract The structure determination of the glutamate dehydrogenase from the hyperthermophile Pyrococcus furiosus has been completed at 2.2 Å 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.