Kalimanovska V, Whitaker K B, Moss D W
Department of Chemical Pathology, Royal Postgraduate Medical School, Hammersmith Hospital, London, UK.
Clin Chim Acta. 1987 Dec;170(2-3):219-25. doi: 10.1016/0009-8981(87)90131-8.
Human alkaline phosphatases extracted with butanol from liver, kidney and placenta, and from foetal and adult small intestine each contain fragments with molecular masses within the range of approximately 8 kDa to 20 kDa which can be removed by digestion with bromelain. However, in the case of adult intestine, this fragment (which is presumed to represent a membrane-binding domain) can only be demonstrated in tissue extracted immediately after removal at operation. Similar fragments are also present in foetal intestinal phosphatase in amniotic fluid, and in liver and bone alkaline phosphatases recovered from serum. Again, however, adult intestinal phosphatase from serum differs in the absence of the bromelain-sensitive fragment. These observations indicate differences in the ways in which intestinal and non-intestinal alkaline phosphatases gain access to the circulation, and also have implications for structural studies on intestinal phosphatase extracted post mortem from adult tissue.
用丁醇从肝脏、肾脏、胎盘以及胎儿和成人小肠中提取的人碱性磷酸酶，各自都含有分子量在大约8 kDa至20 kDa范围内的片段，这些片段可通过菠萝蛋白酶消化去除。然而，就成人小肠而言，这个片段（据推测代表一个膜结合结构域）仅在手术切除后立即提取的组织中才能被证实。羊水内胎儿肠道磷酸酶以及从血清中回收的肝脏和骨碱性磷酸酶中也存在类似片段。不过，血清中的成人肠道磷酸酶再次表现出差异，即不存在对菠萝蛋白酶敏感的片段。这些观察结果表明肠道和非肠道碱性磷酸酶进入循环的方式存在差异，并且对从成人组织死后提取的肠道磷酸酶的结构研究也有影响。
