Extreme biophysics: Enzymes under pressure. Issue 15 (19th January 2017)

• Record Type: Journal Article
• Authors: Huang, Qi; Rodgers, Jocelyn M.; Hemley, Russell J.; Ichiye, Toshiko
• Other Names: Hirst Jonathan guestEditor.; Im Wonpil guestEditor.; Shea Joan‐Emma guestEditor.
• Is Part Of: Journal of computational chemistry. Volume 38:Issue 15(2017)
• Page Start: 1174
• Page End: 1182
• Publication Date: 2017-01-19
• Subjects: pressure and temperature dependence -- atomic fluctuations -- extremophiles; Chemistry -- Data processing -- Periodicals; 542.85
• DOI: 10.1002/jcc.24737
• Languages: English
• ISSNs: 0192-8651

Abstract

Abstract : A critical question about piezophilic (pressure‐loving) microbes is how their constituent molecules maintain function under high pressure. Here, factors are examined that may lead to the increased activity under pressure in dihydrofolate reductase from the piezophilic Moritella profunda compared to the homologous enzyme from the mesophilic Escherichia coli . Molecular dynamics simulations are performed at various temperatures and pressures to examine how pressure affects the flexibility of the enzymes from these two microbes, since both stability and flexibility are necessary for enzyme activity. The results suggest that collective motions on the 10‐ns timescale are responsible for the flexibility necessary for "corresponding states" activity at the growth conditions of the parent organism. In addition, the results suggest that while the lower stability of many enzymes from deep‐sea microbes may be an adaptation for greater flexibility at low temperatures, high pressure may enhance their adaptation to low temperatures. © 2017 Wiley Periodicals, Inc. Abstract : Determining adaptations of enzymes for extreme pressure and temperature is important for understanding structure‐function relationships in enzymes and may help in defining the "limits of life." Atomistic simulations of dihydrofolate reductase from a mesophile and a "piezophile" identify collective motions as responsible for the flexibility necessary for "corresponding states" enzyme activity. In addition, the adaptions for low temperature and high pressure environment of deep‐sea microbes are identified as greater flexibility and lower density.