4′-CyanoPLP presents better prospect for the experimental detection of elusive cyclic intermediate radical in the reaction of lysine 5,6-aminomutase

The results of our calculations suggest that the reaction of 4′-cyanoPLP with lysine 5,6-aminomutase offers better prospect for the experimental detection of elusive cyclic azacyclopropylcarbinyl radical, which is proposed to be a key intermediate in the reaction of pyridoxal-5′-phosphate dependent radical aminomutases. [Display omitted] •4′-CyanoI is the lowest energy radical intermediate in the reaction of 5,6-LAM.•4′-CyanoPLP offers good prospect for the experimental observation of elusive I.•The calculated HFCCs would help to characterize 4′-cyanoI by EPR. The results of our calculations suggest that the reaction of 4′-cyanoPLP with lysine 5,6-aminomutase offers better prospect for the experimental detection of elusive cyclic azacyclopropylcarbinyl radical (I), which is proposed to be a key intermediate in the reaction of pyridoxal-5′-phosphate dependent radical aminomutases. We have calculated the corresponding hyperfine coupling constants (HFCCs) for 14N and 13C of cyano group using several basis sets to help the characterization of 4′-cyanoI.