AFFINITIES OF AMINO-ACID SIDE-CHAINS FOR SOLVENT WATER
AFFINITIES OF AMINO-ACID SIDE-CHAINS FOR SOLVENT WATER
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DOI：
10.1021/bi00507a030
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发表时间：
1981-01-01
期刊：
影响因子：
2.9
通讯作者：
SOUTHGATE, CCB
中科院分区：
文献类型：
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作者：
WOLFENDEN, R;ANDERSSON, L;SOUTHGATE, CCB
氨基酸侧链在其稀水溶液和25 ℃下的气相之间的分布平衡通过动态蒸汽压测量确定。在校正至pH 7后，所得的水合势标度，或从汽相到中性水溶液的转移自由能，跨越约0.5的范围。22千卡/摩尔。精氨酸的侧链比其他常见氨基酸的侧链亲水得多，平衡常数为aptx。1015用于从气相转移到中性水溶液。水化势与各种氨基酸出现在球状蛋白表面的相对趋势的相关性比早期对游离氨基酸的分布研究所证明的更为密切。这两种特性都与遗传密码中的明显偏差有关。
Equilibria of distribution of amino acid side chains, between their dilute aqueous solutions and the vapor phase at 25.degree. C, were determined by dynamic vapor pressure measurements. After correction to pH 7 the resulting scale of hydration potentials, or free energies of transfer from the vapor phase to neutral aqueous solution, spans a range of .apprx. 22 kcal/mol. The side chain of arginine is much more hydrophilic than those of the other common amino acids, with an equilibrium constant of .apprx. 1015 for transfer from the vapor phase to neutral aqueous solution. Hydration potentials are more closely correlated with the relative tendencies of the various amino acids to appear at the surface of globular proteins than had been evident from earlier distribution studies on the free amino acids. Both properties are associated with a pronounced bias in the genetic code.