Fig. 2: Lack of selectivity between SAM and SAH and a major reason.
From: Magnesium ions mediate ligand binding and conformational transition of the SAM/SAH riboswitch
a Interaction energies of individual nucleotides with the ligands. For each nucleotide, triangle and error bar represent the mean and standard deviation, respectively, calculated among results from 10 starting models. A horizontal line at −2.0 kcal/mol separates out the five pocket-lining nucleotides. b The solvent exposure of the SAM aminocarboxypropyl group, especially the methyl (C15), illustrated by a snapshot from the MD simulations under saturating Mg2+. The backbone of the groove-lining nucleotides 5–8 and 12–16 is in orange.
