Mcdonagh J, Waggoner W G, Hamilton E G, Hindenbach B, Mcdonagh R P
Biochim Biophys Acta. 1976 Oct 28;446(2):345-57. doi: 10.1016/0005-2795(76)90002-7.
A method for affinity chromatography of plasma and platelet factor XIII has been developed, based on known structural characteristics of these molecules. Plasma factor XIII is composed of a and b subunits which are held together by noncovalent interactions; platelet factor XIII has only a subunits. a subunit contains free sulfhydryl groups, while in b subunit all the cystines form disulfide bonds. The affinity gel is an organomercurial agarose with p-chloromercuribenzoate as the reactive group. Both the zymogen and activated forms of a subunit reversibly bind to the ligand by forming covalent mercaptide bonds and are eluted by reducing agents. b subunit does not bind to the affinity gel and is held to it only through interaction with a subunit. Affinity chromatography can be used to purify plasma and platelet factor XIII and to study interactions of the subunits. Experiments on the affinity chromatography of purified plasma factor XIII in several stages of activation agree with earlier observations that activation is a two-step procedure in which b subunit is not quantitatively released from the complex until the final stage of activation by Ca2+.
基于血浆和血小板因子 XIII 的已知结构特征，已开发出一种用于它们亲和层析的方法。血浆因子 XIII 由通过非共价相互作用结合在一起的 a 亚基和 b 亚基组成；血小板因子 XIII 仅含有 a 亚基。a 亚基含有游离巯基，而 b 亚基中的所有胱氨酸均形成二硫键。亲和凝胶是一种以对氯汞苯甲酸为反应基团的有机汞琼脂糖。a 亚基的酶原形式和活化形式均通过形成共价硫醇盐键与配体可逆结合，并被还原剂洗脱。b 亚基不与亲和凝胶结合，仅通过与 a 亚基的相互作用而与之结合。亲和层析可用于纯化血浆和血小板因子 XIII 并研究亚基间的相互作用。对纯化的血浆因子 XIII 在几个活化阶段进行亲和层析的实验与早期观察结果一致，即活化是一个两步过程，其中直到被 Ca2+ 激活的最后阶段，b 亚基才从复合物中定量释放。
