The usefulness of the solubility prediction method is demonstrated using relatively small peptide fragments of human proinsulin C-peptide. The propriety of the solubility prediction method for peptides having polar side chains is also examined in the following respects: (1) Peptide intermediates smaller than a heptapeptide have high solubility regardless of their
values; (2) the values of peptide intermediates are useful for judging solubility of peptide intermediates equal to or larger than an octapeptide level; (3) the Pro residue in a central position of a peptide chain is effective for increasing peptide solubility; and (4) there is critical chain length for peptide insolubility caused by a β-sheet aggregation. A strategy suitable for the design of the synthetic route for human proinsulin C-peptide is subsequently discussed on the basis of the solubility prediction of peptide intermediates.
利用相对较小的人类胰岛素原C肽片段,展示了溶解度预测方法的实用性。还从以下方面考察了该溶解度预测方法对于含有极性侧链肽的适用性:(1)小于七肽的肽中间体具有高溶解性,与其
值无关;(2)肽中间体的值有助于判断等于或大于八肽水平的肽中间体的溶解度;(3)肽链中央位置的Pro残基能有效提高肽的溶解度;(4)存在导致β折叠聚集体引起的不溶性的临界链长度。随后,在肽中间体溶解度预测的基础上,讨论了适用于人胰岛素原C肽合成路线设计的策略。