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PubMed · 6501300

Ultrasensitivity in biochemical systems controlled by covalent modification. Interplay between zero-order and multistep effects.

A Goldbeter·D E Koshland
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Abstract

A previous analysis of covalent modification systems (Goldbeter, A., and Koshland, D. E., Jr. (1981) Proc. Natl. Acad. Sci. U. S. A. 78, 6840-6844) showed that steep transitions in the amount of modified protein can occur when the converter enzymes are saturated by their protein substrate. This "zero-order ultrasensitivity" can further be amplified when an effector acts at more than one step in a monocyclic or multicyclic cascade of covalent modification. We analyze the limitations of the latter "multistep ultrasensitivity" and show how it can combine with the zero-order effect to enhance the sensitivity of biochemical systems controlled by covalent modification.

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Allosteric RegulationKineticsMathematicsModels, BiologicalProtein BindingProteinsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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A Goldbeter, D E Koshland. 1984-12-10. Ultrasensitivity in biochemical systems controlled by covalent modification. Interplay between zero-order and multistep effects.. https://pubmed.ncbi.nlm.nih.gov/6501300/

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