system
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How do isotopes affect protein folding? 

How do isotopes of different sizes affect protein folding? Is the effect negligible, can too many isotopes of a certain mass disturb the proper folding of a protein? Thanks in advance, askscience.
gpt
It's negligible. Isotope substitutions only affect kinetics, really. In _theory_ that could change folding by causing one folding path to become kinetically favored over another. In reality it doesn't seem very likely that evolution/biology would produce a protein that was _that_ sensitive to kinetics (and thus temperature). It'd end up misfolding too often even without the isotopes.