Callens R E, Anteunis M J
Biochim Biophys Acta. 1979 Apr 25;577(2):337-45. doi: 10.1016/0005-2795(79)90037-0.
Although the main characteristics of the parent virginiamycin S conformation i.e. a bend of type VI (Lewis, P.N., Momamy, F.A. and Scheraga, H.A. (1973) Biochim. Biophys. Acta 303, 211--229) formed by the Pro-N-MePhe-X-PhGly sequence is still present in patricin A, the substitution of X = pipecolic acid by proline in the latter results in a destabilization of the tertiary structure of the depsipeptide, since two isomeric states of a peptidic bond appear in C2HC13 solution. Addition of +/- 30% (v:v) (C2H3)2SO totally shifts this equilibrium in favor of the major parent isomer. These results completely fit with what is known up to now on the occurrence and structure of turns (Chou and Fasman (1977) J. Mol. Biol. 115,135--175).
尽管由Pro-N-MePhe-X-PhGly序列形成的母体维吉尼亚霉素S构象的主要特征，即VI型弯曲（Lewis, P.N., Momamy, F.A.和Scheraga, H.A. (1973) Biochim. Biophys. Acta 303, 211 - 229）在派利霉素A中仍然存在，但后者中X = 哌啶酸被脯氨酸取代导致了缩肽三级结构的不稳定，因为在C2HC13溶液中出现了肽键的两种异构状态。添加+/- 30%（v:v）的（C2H3）2SO会完全使这种平衡向主要母体异构体方向移动。这些结果与目前已知的关于转角的出现和结构的情况（Chou和Fasman (1977) J. Mol. Biol. 115,135 - 175）完全吻合。
