Palekar D, Shiue M, Lien E J
Department of Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles 90033, USA.
Pharm Res. 1996 Aug;13(8):1191-5. doi: 10.1023/a:1016008102587.
This paper attempts to correlate the hydrophobic contribution constants (faa) of 21 amino acids in small peptides with commonly used physiochemical parameters. These faa constants can then be used to predict hydrophobicity change in peptides when any one of the amino acid residue is substituted with another.
Non-weighted least squares method was used in deriving regression equations with a BMDP program. A Hyperchem program for Windows was used to calculate the group dipole moments of the side chain.
A good correlation (r = 0.97) was obtained using a four parameter equation including molecular weight (log MW), hydrogen bond forming ability (HB), dipole moment (mu) and an indicator variable (I) to account for the presence of a free primary amine group in the side chain.
This proposed model should be useful in predicting the hydrophobic contribution constants of other uncommon amino acids and in the estimation of log P'values of numerous peptides containing different possible combinations of these amino acids, as well as log P' values resulting from amino acid substitution as is done in site-directed mutagenesis.
本文试图将小肽中21种氨基酸的疏水贡献常数（faa）与常用的物理化学参数相关联。这些faa常数随后可用于预测当任何一个氨基酸残基被另一个取代时肽的疏水性变化。
使用非加权最小二乘法，通过BMDP程序推导回归方程。使用适用于Windows的Hyperchem程序计算侧链的基团偶极矩。
使用包含分子量（log MW）、氢键形成能力（HB）、偶极矩（μ）和一个指示变量（I）的四参数方程获得了良好的相关性（r = 0.97），该指示变量用于说明侧链中游离伯胺基团的存在。
该模型在预测其他不常见氨基酸的疏水贡献常数以及估算包含这些氨基酸不同可能组合的众多肽的log P'值，以及如定点诱变中氨基酸取代产生的log P'值方面应是有用的。
