Cyclized dipeptide model for a beta-bend.

R Deslauriers; S J Leach; F R Maxfield; E Minasian; J R McQuie; Y C Meinwald; G Némethy; M S Pottle; I D Rae; H A Scheraga; E R Stimson; J W Van Nispen

doi:10.1073/pnas.76.6.2512

PubMed · 288041

Cyclized dipeptide model for a beta-bend.

R Deslauriers·S J Leach·F R Maxfield·E Minasian·J R McQuie·Y C Meinwald·G Némethy·M S Pottle·I D Rae·H A Scheraga·E R Stimson·J W Van Nispen

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Abstract

A cyclic dipeptide in which L-Ala-Gly was cyclized with epsilon-aminocaproic acid has been synthesized as a model for a beta-bend. Its conformational properties have been examined by means of conformational energy calculations and nuclear magnetic resonance, infrared, Raman, and circular dichroism spectroscopy in various solvents. These calculations and experiments suggest that a type II beta-bend exists in the Ala-Glymoiety, with an NH...O = C hydrogen bond in the epsilon-aminocaproic acid portion of the molecule, and that the molecule adopts a unique conformation in solution. In contrast, an open-chain analog of this compound exists in solution as an ensemble of conformations but with a significant amount of a type II beta-bend structure in the ensemble.

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Circular Dichroism Dipeptides Magnetic Resonance Spectroscopy Peptides, Cyclic Protein Conformation Spectrum Analysis, Raman Journal Article Research Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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R Deslauriers, S J Leach, F R Maxfield, E Minasian, J R McQuie, Y C Meinwald, G Némethy, M S Pottle, I D Rae, H A Scheraga, E R Stimson, J W Van Nispen. 1979. Cyclized dipeptide model for a beta-bend.. https://doi.org/10.1073/pnas.76.6.2512

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