Oshima G, Shimabukuro H, Nagasawa K
Biochim Biophys Acta. 1979 Jan 12;566(1):128-37. doi: 10.1016/0005-2744(79)90255-9.
Peptide inhibitors of angiotensin I-converting enzyme (peptidyldipeptide hydrolase, EC 3.4.15.1) were produced by digesting gelatin with bacterial collagenase. The inhibitors were isolated from the digests with a combination of alcohol fractionation, treatment with Amberlite CG-50 column, gel filtration through Sephadex G-25, and Dowex 50 column and paper chromatography. Nine peptide fractions were purified to apparent homogeneity judging by thin-layer and ion-exchange column chromatography, and amino acid composition. Amino acid sequences of the peptides were determined: 2 were found to be mixtures of peptides and the sequence of another was only partially determined. Six of the peptides were potent inhibitors of the converting enzyme, while the other three were less active. 6 peptides were substrates for the enzyme. The enzyme released a dipeptide, Ala-Hyp from one peptide and was strongly inhibited by this dipeptide. The remainder of the parent peptides was a less effective inhibitor.
通过用细菌胶原酶消化明胶来制备血管紧张素I转换酶（肽基二肽水解酶，EC 3.4.15.1）的肽抑制剂。通过乙醇分级分离、用Amberlite CG-50柱处理、经Sephadex G-25凝胶过滤、Dowex 50柱和纸色谱法相结合的方式从消化物中分离出抑制剂。通过薄层和离子交换柱色谱法以及氨基酸组成判断，九个肽级分被纯化至表观均一性。测定了这些肽的氨基酸序列：发现2个是肽的混合物，另一个的序列仅部分确定。其中六个肽是转换酶的强效抑制剂，而另外三个活性较低。6个肽是该酶的底物。该酶从一个肽中释放出二肽Ala-Hyp，并被该二肽强烈抑制。亲本肽的其余部分是效果较差的抑制剂。
