Buttle D J, Barrett A J
Biochem J. 1984 Oct 1;223(1):81-8. doi: 10.1042/bj2230081.
Chymopapain (EC 3.4.22.6) was purified from commercially available spray-dried latex of papaya (Carica papaya) fruit by (NH4)2SO4 fractionation and fast protein chromatography on the Mono S cation-exchange column. Multiple forms of chymopapain separated chromatographically were shown to be immunologically identical. A major form was isolated and found to be homogeneous by several criteria, and fully active, and its N-terminal amino acid was identified as tyrosine. Latex from fresh unripe papaya fruit contained predominantly one form of chymopapain, and it is concluded that chymopapain is a single enzyme distinct from the other cysteine proteinases of C. papaya latex.
木瓜凝乳蛋白酶（EC 3.4.22.6）通过硫酸铵分级分离和在Mono S阳离子交换柱上的快速蛋白质色谱法，从市售的木瓜（番木瓜）果实喷雾干燥乳胶中纯化得到。通过色谱法分离出的多种形式的木瓜凝乳蛋白酶经免疫鉴定具有同一性。分离出一种主要形式，经多种标准鉴定为均一的，且具有完全活性，其N端氨基酸被鉴定为酪氨酸。新鲜未成熟木瓜果实的乳胶主要含有一种形式的木瓜凝乳蛋白酶，由此得出结论，木瓜凝乳蛋白酶是一种与番木瓜乳胶中的其他半胱氨酸蛋白酶不同的单一酶。
