Microscopic derivation of the low‐T myoglobin‐CO recombination rate law by estimating statistical parameters of folding relaxation

Abstract

AbstractThe low‐T recombination of carbon monoxide (CO) to myoglobin (Mb) obeys a rate law interpreted as a superposition of appropriately‐weighted Arrhenius‐type relaxations. We derive this rate law from microscopic principles by determining the random activation energy landscape for short timescale interconversion of myoglobin conformational substates that preserve CO‐storage capacity. Thus, the random energy model (REM) first introduced in the context of protein folding by Bryngelson and Wolynes is applied here to derive the nonexponential rate law of a reaction ‐ Mb‐CO recombination — built upon an REM‐type distribution of substate reactants.