Temperature response of biological systems

Vic and Louis before WaiBOP conference

Vic and Louis before WaiBOP conference

In collaboration with a project led by Vic Arcus , we have been looking at how temperature controls biological reactions. Specifically, Vic has built on the equations developed by Arrhenius and Gibbs to capture the importance of the enzyme’s heat capacity to predict rates of enzyme-catalysed reactions.

A recent presentation on the implications for soil biogeochemistry by Louis can be found here and an overview of the implications of the theory more generally is summarised in the paper here.

MMRT works very well – predicting a temperature optimum for enzyme activity without requiring denaturation. MMRT also allows determination of Tinf – the temperature at  which the temperature sensitivity is maximal, i.e., when the rate of change in activity is maximal for a change in temperature. Importantly, these equations are also very useful for predicting soil biological activity such as respiration, see main papers below:

Schipper, L.A.; Hobbs, J.K.; Rutledge S.; Arcus, V.L. (2014) Thermodynamic theory explains the temperature optima of soil microbial processes and High Q10 Values at Low Temperatures. Global Change Biology. DOI: 10.1111/gcb.12596

Arcus, V.L.; Prentice, E.; Hobbs, J.K.; Mulholland, A.J.; Vander Kamp, M.W.; Pudney, C.R.; Parker, E.J.; Schipper, L.A. (2016) On the temperature dependence of enzyme-catalysed rates. Biochemistry. 55: 1681-1688. ACS Editors’ Choice

Hobbs, J.K.; Jiao, W.; Easter, A.D.; Parker, E.J.; Schipper, L.A.; Arcus, V.L. (2013) The Change in Heat Capacity for Enzyme Catalysis Determines the Temperature Dependence of Enzyme Catalysed Rates. ACS Chemical Biology. 8: 2388-2393.

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