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从锌诱导的家兔肝脏中分离纯化得到金属硫蛋白两种亚型：ＺｎＭＴ－Ⅰ和ＺｎＭＴ－Ⅱ．在酸性条件下脱金属，经Ｓｅｐｈａｄｅｘ Ｇ－２５柱层析得到脱金属硫蛋白（ａｐｏＭＴｓ）．用圆二色性（ＣＤ）光谱法研究，发现两种亚型ａｐｏＭＴｓ 与Ｐｂ２＋ 的结合依赖于Ｐｂ２＋ 的加入比例及ｐＨ 值．ａｐｏＭＴ－Ⅰ在ｐＨ３～５之间，ａｐｏＭＴ－Ⅱ在ｐＨ４～６之间与Ｐｂ２＋ 结合形成特征簇合物Ｐｂ７ＭＴｓ，其ＣＤ谱图特征峰位于３１６ｎｍ （－ ），２７０ ｎｍ （＋ ），２４５ ｎｍ （＋ ）及２２５ ｎｍ （－ ），提示解铅中毒的最佳条件应控制在弱酸性环境．不同亚型ａｐｏＭＴｓ 与Ｐｂ２＋ 的结合方式各不相同：Ｐｂ２＋ 与ａｐｏＭＴ－Ⅰ的结合采取平均分配的方式，而与ａｐｏＭＴ－Ⅱ则为选择性结合方式，表明这两种亚型在解铅毒功能上存在差异．
Two subtypes of metallothionein, ZnMT-I and ZnMT-II, were isolated and purified from zinc-induced rabbit liver. Demetalization under acidic conditions gave demetallothioneins (apoMTs) on a Sephadex G-25 column. Using circular dichroism (CD) spectroscopy, it was found that the binding of apoMTs to Pb2 + was dependent on the addition of Pb2 + and pH. ApoMT-Ⅰ was found to be a cluster of Pb7MTs with Pb2 + at a pH of 4 ~ 6 at a pH of 3 ~ 5. The characteristic peaks of the CD spectra were at 316 nm (-), 270 nm (+) and 245 nm +) And 225 nm (-), suggesting that the optimal solution of lead poisoning should be controlled in a weak acid environment. Different subtypes of apoMTs and Pb2 + binding in different ways: Pb2 + and apoMT-Ⅰ combination of the average distribution of the way, and apoMT-Ⅱ is the selective binding mode, indicating that the two subtypes in the solution of lead poisoning function has a difference.