Nethery A, O'Grady R L
Department of Pathology, University of Sydney, Australia.
Biochim Biophys Acta. 1989 Feb 2;994(2):149-60. doi: 10.1016/0167-4838(89)90154-4.
A metalloproteinase similar or identical to stromelysin was shown to co-purify with interstitial collagenase from the rat mammary carcinoma cell line, BC1. The mixture of BC1 metalloproteinase and collagenase degraded casein, gelatin, fibronectin, fibrinogen, laminin, proteoglycan and type IV collagen, in addition to types I and II collagen. Using SDS-PAGE and zymography, the Mr of both enzymes was 51.10(3). During storage, the 51.10(3) protein converted to fragments of Mr 34.10(3) and 24.10(3), and isoelectric points of 4.6-5.3 and 5.7-6.0, respectively. The fragments were separated from the intact (Mr 51.10(3) enzymes by DEAE-Sepharose chromatography, but intact metalloproteinase and collagenase activities resisted separation by a range of chromatographic methods. The Mr 34.10(3) fragment retained the proteinolytic activities of the intact enzymes, excepting collagenase cleavage of collagen types I and II. The Mr 24.10(3) fragment had no proteinolytic activity, showed an increase in Mr of 6.10(3) upon reduction, in common with the intact enzymes, and also had similar chromatographic properties to the intact enzymes. The data presented are consistent with a pattern of breakdown which is common to both collagenase and the metalloproteinase, and suggest that both enzymes are comprised of two protein domains.
一种与基质溶素相似或相同的金属蛋白酶，被证明可与大鼠乳腺癌细胞系BC1中的间质胶原酶共同纯化。除了I型和II型胶原外，BC1金属蛋白酶和胶原酶的混合物还能降解酪蛋白、明胶、纤连蛋白、纤维蛋白原、层粘连蛋白、蛋白聚糖和IV型胶原。使用SDS - PAGE和酶谱法，两种酶的相对分子质量均为51×10³。在储存过程中，51×10³的蛋白质转化为相对分子质量为34×10³和24×10³的片段，其等电点分别为4.6 - 5.3和5.7 - 6.0。通过DEAE - 琼脂糖层析将片段与完整的（相对分子质量51×10³）酶分离，但完整的金属蛋白酶和胶原酶活性在一系列层析方法中均未被分离。相对分子质量34×10³的片段保留了完整酶的蛋白水解活性，但I型和II型胶原的胶原酶裂解活性除外。相对分子质量24×10³的片段没有蛋白水解活性，与完整酶一样，还原后相对分子质量增加6×10³，并且其层析特性也与完整酶相似。所呈现的数据与胶原酶和金属蛋白酶共有的降解模式一致，并表明这两种酶均由两个蛋白质结构域组成。
