Foltmann B, Pedersen V B, Kauffman D, Wybrandt G
J Biol Chem. 1979 Sep 10;254(17):8447-56.
The complete amino acid sequence of calf chymosin (rennin) (EC 3.4.23.4) has been determined. The sequence consists of a single peptide chain of 323 amino acid residues. The primary structure of the precursor part of calf prochymosin was published previously (Pedersen, V.B., and Foltmann, B. (1975) Eur. J. Biochem. 55, 95-103), thus we are now able to account for the total 365 amino acid residues of calf prochymosin. Comparison of the sequence of calf prochymosin with that of pig pepsinogen A (EC 3.4.23.1) shows extensive homology. In the precursor part of the sequence, 15 residues are located at identical positions, as compared to 189 identical residues in the respective enzymes. Furthermore comparison to Penicillium janthinellum acid proteinase (penicillopepsin) (EC 3.4.23.7) shows that 76 residues are common to this enzyme and to the two gastric proteinases. These homologies in sequence further suggest that the folding of the peptide chain in chymosin is very similar to that of other acid proteinases.
已确定小牛凝乳酶（胃蛋白酶）（EC 3.4.23.4）的完整氨基酸序列。该序列由一条含323个氨基酸残基的单肽链组成。小牛前凝乳酶前体部分的一级结构先前已发表（佩德森，V.B.，和福尔茨曼，B.（1975年）《欧洲生物化学杂志》55卷，95 - 103页），因此我们现在能够确定小牛前凝乳酶总共365个氨基酸残基的情况。将小牛前凝乳酶的序列与猪胃蛋白酶原A（EC 3.4.23.1）的序列进行比较，发现有广泛的同源性。在序列的前体部分，有15个残基位于相同位置，而在各自的酶中有189个相同残基。此外，与产黄青霉酸性蛋白酶（青霉胃蛋白酶）（EC 3.4.23.7）比较表明，该酶与这两种胃蛋白酶有76个共同残基。这些序列同源性进一步表明，凝乳酶中肽链的折叠与其他酸性蛋白酶非常相似。
