Proteolytic enzymes in yolk-sac membrane of quail egg. Purification and enzymatic characterisation
Proteolytic enzymes in yolk-sac membrane of quail egg. Purification and enzymatic characterisation
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DOI：
10.1016/s0305-0491(97)00034-5
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发表时间：
1997-09-01
影响因子：
2.2
通讯作者：
Wittmann, J
中科院分区：
文献类型：
--
作者：
Gerhartz, B;Auerswald, EA;Wittmann, J
蛋黄蛋白的降解对于禽类胚胎的早期发育是必不可少的。在日本鹌鹑(Coturnix Coturnix Japan Onica)中，卵黄周围组织，即卵黄囊膜中的蛋白分解，可以被半胱氨酸蛋白酶和天冬氨酸蛋白酶的类特异性抑制剂所抑制。纯化后得到一种半胱氨酸蛋白酶和一种天冬氨酸蛋白酶，表观分子量分别为29kD和44kD。这两种酶都是以双链形式纯化的，但在卵黄囊膜匀浆中也存在单链形式。通过NH2末端序列分析和动力学研究，确定该半胱氨酸水解酶为一种新的组织蛋白酶B。与哺乳动物组织蛋白酶B一样，这种禽类组织蛋白酶B具有两种不同的蛋白水解酶活性，即内肽酶活性和二肽基羧肽酶活性。蛋白类半胱氨酸蛋白酶抑制剂蛋清半胱氨酸蛋白酶抑制蛋白的平衡解离常数(K-I)为3.3 nM。同样，天冬氨酸蛋白酶被鉴定为一种新的组织蛋白酶D。这个禽类组织蛋白D与所有已知的哺乳动物组织蛋白D具有不同的加工位点。在鹌鹑组织蛋白D中，一个NH2末端与哺乳动物组织蛋白D中的211-230个氨基酸同源，这是哺乳动物加工位点下游的100多个氨基酸。比较了鹌鹑和牛组织蛋白酶D的酶学性质，结果表明，不同的加工部位对酶的性质没有影响。(C)1997年爱思唯尔科学公司。
Degradation of yolk protein is essential for the early development of the avian embryo. In Japanese quail (Coturnix coturnix japonica), proteolysis in the surrounding tissue of the yolk, the yolk-sac membrane, can be inhibited by class-specific inhibitors of cysteine proteinases as well as of aspartic proteinases. Purification of the enzymes leads to one cysteine proteinase and one aspartic proteinase with an apparent molecular mass of 29 kD and 44 kD, respectively. Both enzymes were purified in a two-chain form, although a single-chain form is also present in the homogenate of yolk sac membrane. The cysteine proteinase was identified by NH2-terminal sequence analysis as well as by kinetic studies as a new cathepsin B from quail. Like mammalian cathepsin B, this avian cathepsin B exhibits two different kinds of proteolytic activity, an endopeptidase activity and a dipeptidyl carboxypeptidase activity. Chicken egg white cystatin, a protein-aceous cysteine proteinase inhibitor, inhibits quail cathepsin B with an equilibrium dissociation constant (K-i) of 3.3 nM. Likewise the aspartic proteinase was identified as a new cathepsin D from quail. This avian cathepsin D has a different processing site to all known mammalian cathepsins D. In quail cathepsin D one NH2-termini is homologous to amino acids 211-230 in mammalian cathepsin D. This is more than 100 amino acids downstream of the mammalian processing site. Comparison of the enzymatic properties of quail and bovine cathepsin D indicate that the different processing site has no influence on the enzymatic properties. (C) 1997 Elsevier Science Inc.