Cold-adapted enzymes.

Khawar Sohail Siddiqui; Ricardo Cavicchioli

doi:10.1146/annurev.biochem.75.103004.142723

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Cold-adapted enzymes.

Khawar Sohail Siddiqui·Ricardo Cavicchioli

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Abstract

By far the largest proportion of the Earth's biosphere is comprised of organisms that thrive in cold environments (psychrophiles). Their ability to proliferate in the cold is predicated on a capacity to synthesize cold-adapted enzymes. These enzymes have evolved a range of structural features that confer a high level of flexibility compared to thermostable homologs. High flexibility, particularly around the active site, is translated into low-activation enthalpy, low-substrate affinity, and high specific activity at low temperatures. High flexibility is also accompanied by a trade-off in stability, resulting in heat lability and, in the few cases studied, cold lability. This review addresses the structure, function, and stability of cold-adapted enzymes, highlighting the challenges for immediate and future consideration. Because of the unique properties of cold-adapted enzymes, they are not only an important focus in extremophile biology, but also represent a valuable model for fundamental research into protein folding and catalysis.

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Adaptation, Biological Animals Cold Temperature Enzyme Stability Enzymes Mathematics Protein Conformation Protein Folding Static Electricity Structure-Activity Relationship Surface Properties Thermodynamics Journal Article Research Support, Non-U.S. Gov't Review

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Khawar Sohail Siddiqui, Ricardo Cavicchioli. 2006. Cold-adapted enzymes.. https://doi.org/10.1146/annurev.biochem.75.103004.142723

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