The anomeric effect is a chemical phenomenon that refers to an observed stabilization of six-membered carbohydrate rings when they contain an electronegative substituent at the C1 position of the ring. This stereoelectronic effect influences the three-dimensional shapes of many biological molecules, but the underlying physical origin is unclear. Here it is shown that complexes formed between a truncated peptide motif and an isolated sugar in the gas phase are nearly identical structurally; however, the strength of the polarization of their interactions with the peptide differs greatly. It will be important to re-evaluate the influence, and biological effects, of substituents at position C2 of the six-membered carbohydrate rings.
- Emilio J. Cocinero
- Pierre Carcabal
- Benjamin G. Davis