Quantitative theorization of murburn electron-transfers and murzyme catalysis

The seminal Michaelis-Menten theorization for biological catalysis was based on “transition state”, involving the formation of topologically complementary substrate (S) and enzyme (E) complex (ES) at the ‘active site’ of the latter. Rudolph Marcus put forth the theory of outer sphere electron transfer (ET) in a redox system of “donor-acceptor” complex, which was seen as a foundational framework for understanding ET reactions in chemical systems. While the active-site treatment of Michaelis-Menten may not be relevant in promiscuous redox enzymes, Marcus theory’s applicability to biological ET (BET) systems can be limited, particularly in interfacial scenarios. First, I establish the “mathematical” NECESSITY to venture beyond the “active-site constraints” of interpreting redox enzyme kinetics and BETs. Further, given that (i) the standing models of the redox cascades of mitochondria, photon-processing machinery of chloroplasts and the information relaying physiological systems like neurons are discredited beyond redemption, and (ii) tangible/viable murburn models have been proposed in lieu for such systems, it is now an imperative mandate for availing quantitative murburn relations regarding the same. Towards achieving this ultimate goal for complex cases, herein, I present the foundational considerations of murburn catalysis and BET in much simpler systems, under various assumptions/limitations. While some derivations are from ab initio considerations, others are heuristic/empirical, often needing experimental fitting.