4WHA:
reference: Extremely elevated room-temperature kinetic isotope effects quantify the critical role of barrier width in enzymatic C-H activation., Hu S, Sharma SC, Scouras AD, Soudackov AV, Carr CA, Hammes-Schiffer S, Alber T, Klinman JP, J Am Chem Soc. 2014 Jun 11;136(23):8157-60. doi: 10.1021/ja502726s. Epub 2014 Jun, 2. PMID: 24884374

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