Conformational studies on polypeptide models of collagen. Poly(Gly‐Pro‐Val), poly(Gly‐Pro‐Met), poly(Gly‐Val‐Pro) and poly(Gly‐Met‐Pro)

Abstract

The title polytripeptides were synthesized and studied experimentally, by circular dichroism, and theoretically, by quantum mechanical methods. With the exception of poly(Gly-Pro-Val), which was found to be essentially structureless in solution, the other polymers adopt folded conformations, most probably of type II beta-bends. Conclusions from theoretical studies were generally in agreement with the experimental results. In particular, it is noteworthy that the optimized (phi, psi) maps for poly(Gly-Pro-Met) showed the absolute minimum (phi = 60 degree, psi = 0 degrees) located inside the beta II bend space.