There is a growing interest in the applications of non-equilibrium quantum dynamics to describe biological processes (I'm not talking here about Penrose's old theories, but new stuff -- quantum coherence in light harvesting, magnetoreception etc.). What is the biologists' take on this? Is this just a whim of physicists looking for grants, or a serious part of biological research?
Absolutely a serious part of research - quantum mechanics defines chemical structure and reactivity. Whenever you see a headline like 'Scientists find quantum effects important in protein activity, weird huh?', read it as 'Scientists find pragmatic classical approximations inadequate in describing protein activity'.
In protein structure, for example, classical molecular dynamics/mechanics are important in generating computationally tractable problems, however they represent a tacit and streamlined parameterisation of underlying quantum mechanics. QM protein structures are usually too gnarly to compute (at least historically speaking), except in regions of interest like an active site, where a model fine-tuned for sequences of amino acids will probably fail badly anyway. As a concrete example, the group that I'm in is in part interested in computationally modelling the active site of plant photosystem II, which contains a cluster of spin-coupled manganese atoms. To glean any useful understanding of how this cluster functions via a computational model, an explicit quantum mechanical level of theory that takes into account electron exchange and correlation must be used. This requirement can probably be extended to any metalloenzyme.
And this isn't touching upon the resonance hole transfer that oxidises the active site, the Davydov solitons that manifest in protein alpha helices, or indeed the quantum electrodynamical origins of the Van der Waals interaction that causes everything to tend to stick to everything else.
Hope this is interesting :D
(note: I am not involved with PetaChem, I just think it's freaking awesome.)
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