单宁酸对聚（L-精氨酸）和聚（L-赖氨酸）的差异固定作用及其在电子显微镜下对胶原蛋白固定的应用。

Differential fixation of poly(L-arginine) and poly(L-lysine) by tannic acid and its application to the fixation of collagen in electron microscopy.

作者信息

Meek K M, Weiss J B

出版信息

Biochim Biophys Acta. 1979 Sep 20;587(1):112-20. doi: 10.1016/0304-4165(79)90225-3.

Abstract

A differential fixation of poly(L-arginine) and poly(L-lysine) has been demonstrated by means of cellulose acetate electrophoresis and colorimetric titration. Electrophoresis showed that at pH 3.0 and concentrations between 0.025% and 2% the reagent interacts with poly(L-arginine) but not with poly(L-lysine). At pH 7.5, however, poly(L-lysine) also reacts, although at a higher concentration of tannic acid than was required to fix poly(L-arginine) at this pH. Colorimetric titration revealed that for poly(L-arginine) the reaction with tannic acid commences at pH 3.0 and is complete at pH 4.1 whereas for poly(L-lysine) the reaction commences at pH 3.5 and is complete at pH 4.9. It is suggested that the reaction is predominantly electrostatic. The results are discussed in relation to the use of tannic acid as a protein fixative in electron microscopy.

摘要

通过醋酸纤维素电泳和比色滴定法已证明了聚（L-精氨酸）和聚（L-赖氨酸）的差异固定作用。电泳显示，在pH 3.0以及浓度介于0.025%至2%之间时，该试剂与聚（L-精氨酸）相互作用，但不与聚（L-赖氨酸）相互作用。然而，在pH 7.5时，聚（L-赖氨酸）也会发生反应，尽管此时所需的单宁酸浓度高于在该pH下固定聚（L-精氨酸）所需的浓度。比色滴定表明，对于聚（L-精氨酸），与单宁酸的反应在pH 3.0时开始，在pH 4.1时完成；而对于聚（L-赖氨酸），反应在pH 3.5时开始，在pH 4.9时完成。据推测，该反应主要是静电作用。结合单宁酸在电子显微镜中作为蛋白质固定剂的用途对结果进行了讨论。