Cation–π Interactions in Nature
Nature’s building blocks contain aromatic moieties in high abundance. Recently, it has become clear that many structural features that were once thought to be purely hydrophobic in nature are in fact engaging in cation–π interactions. The amino acid side chains of phenylalanine, tryptophan, tyrosine, histidine, are capable of binding to cationic species such as charged amino acid side chains, metal ions, small-molecule neurotransmitters and pharmaceutical agents. In fact, macromolecular binding sites that were hypothesized to include anionic groups (based on affinity for cations) have been found to consist of aromatic residues instead in multiple cases. Cation-π interactions can tune the pKa of nitrogenous side-chains, increasing the abundancy of the protonated form, this has implications for protein structure and function. While less studied in this context, the DNA bases are also able to participate in cation–π interactions.
Read more about this topic: Cation–pi Interaction
Other articles related to "interactions":
... Cation-π interactions can catalyze chemical reactions by stabilizing buildup of positive charge in transition states ... Polycyclization enzymes also rely on cation-π interactions ... squalene proceed through a (potentially concerted) cationic cascade, cation-π interactions are ideal for stabilizing this dispersed positive charge ...