Moss J, Stanley S J, Osborne J C
J Biol Chem. 1982 Feb 25;257(4):1660-3.
An ADP-ribosyltransferase from turkey erythrocytes which utilizes proteins and low molecular weight guanidino compounds such as arginine and agmatine as ADP-ribose acceptors was stimulated by histones. The effect was specific in that choleragen, a bacterial mono(ADP-ribosyl)transferase that increased adenylate cyclase activity in animal cells, was not activated by histones. With the erythrocyte enzyme, histones decreased the apparent Km values for arginine methyl ester and agmatine and increased the stability of the transferase to thermal denaturation. Activation of the transferase by histones was rapid, with a minimal delay observed upon addition of histones to a histone-free assay. Activation by histones was reversed upon dilution of a sample containing histones into an assay mix free of histone. In the absence of histone, the transferase existed as a rapidly sedimenting species; in the presence of histone, the transferase sedimented as a protomer.
来自火鸡红细胞的一种ADP-核糖基转移酶，其利用蛋白质以及低分子量胍基化合物（如精氨酸和胍丁胺）作为ADP-核糖受体，受到组蛋白的刺激。这种效应具有特异性，因为霍乱毒素（一种可增加动物细胞中腺苷酸环化酶活性的细菌单（ADP-核糖基）转移酶）不会被组蛋白激活。对于红细胞酶，组蛋白降低了精氨酸甲酯和胍丁胺的表观Km值，并增加了转移酶对热变性的稳定性。组蛋白对转移酶的激活迅速，在向无组蛋白的测定体系中添加组蛋白后观察到的延迟最小。当将含有组蛋白的样品稀释到无组蛋白的测定混合物中时，组蛋白的激活作用会逆转。在没有组蛋白的情况下，转移酶以快速沉降的形式存在；在有组蛋白的情况下，转移酶以单体形式沉降。
