一种可能来自水稻种子的淀粉酶/蛋白酶抑制剂的氨基酸序列。

Amino acid sequence of a probable amylase/protease inhibitor from rice seeds.

作者信息

Yu Y G, Chung C H, Fowler A, Suh S W

机构信息

Department of Chemistry, College of Natural Sciences, Seoul National University, Korea.

出版信息

Arch Biochem Biophys. 1988 Sep;265(2):466-75. doi: 10.1016/0003-9861(88)90151-8.

DOI:10.1016/0003-9861(88)90151-8

PMID:2458699

Abstract

The primary structure of a 9-kDa basic protein from rice seeds was determined by gas-phase sequencing of the intact protein and peptides derived from it by digestion with trypsin, chymotrypsin, and endopeptidase Lys-K. The protein consists of a single polypeptide chain of 91 amino acid residues with a calculated molecular mass of 8909 Da. It is rich in alanine, serine, glycine, and cysteine. The eight cysteines form four disulfide bonds. There is no methionine, histidine, phenylalanine, or tryptophan. The sequence is highly homologous with an alpha-amylase inhibitor, I-2, from seeds of Indian finger millet [F. A. P. Campos and M. Richardson (1984) FEBS Lett. 167, 221-225] and a 10-kDa barley seed protein, also called a probable amylase/protease inhibitor [B. Svensson et al. (1986) Carlsberg Res. Commun. 51, 493-500; J. Mundy and J. C. Rogers (1986) Planta 169, 51-63]. In analogy with the barley protein, the purified protein is tentatively called a rice probable amylase/protease inhibitor (PAPI). The rice PAPI does not show inhibitory activities against proteases and amylases tested. The amino acid sequence is as follows: Ile-Thr-Cys-Gly-Gln-Val-Asn-Ser-Ala-Val(10)-Gly-Pro-Cys-Leu-Thr-Tyr- Ala-Arg-Gly-Gly(20)-Ala-Gly-Pro-Ser-Ala-Ala-Cys-Cys-Ser-Gly(30)-Val-Arg- Ser-Leu-Lys-Ala-Ala-Ala-Ser-Thr(40)-Thr-Ala-Asp-Arg-Arg-Thr-Ala-Cys- Asn-Cys(50)-Leu-Lys-Asn-Ala-Ala-Arg-Gly-Ile-Lys-Gly(60)-Leu-Asn-Ala-Gly- Asn-Ala-Ala-Ser-Ile-Pro(70)-Ser-Lys-Cys-Gly-Val-Ser-Val-Pro-Tyr-Thr(80)- Ile-Ser-Ala-Ser-Ile-Asp-Cys-Ser-Arg-Val-Ser(91).

摘要

通过对完整蛋白质及其经胰蛋白酶、胰凝乳蛋白酶和赖氨酸内切酶消化产生的肽段进行气相测序，确定了水稻种子中一种9 kDa碱性蛋白的一级结构。该蛋白由一条含91个氨基酸残基的单多肽链组成，计算分子量为8909 Da。它富含丙氨酸、丝氨酸、甘氨酸和半胱氨酸。八个半胱氨酸形成四个二硫键。不含甲硫氨酸、组氨酸、苯丙氨酸或色氨酸。该序列与来自印度黍种子的α-淀粉酶抑制剂I-2 [F. A. P. 坎波斯和M. 理查森（1984年）《欧洲生物化学学会联合会快报》167, 221 - 225]以及一种10 kDa大麦种子蛋白（也称为可能的淀粉酶/蛋白酶抑制剂）[B. 斯文森等人（1986年）《嘉士伯研究通讯》51, 493 - 500；J. 蒙迪和J. C. 罗杰斯（1986年）《植物》169, 51 - 63]高度同源。与大麦蛋白类似，纯化后的蛋白暂称为水稻可能的淀粉酶/蛋白酶抑制剂（PAPI）。水稻PAPI对所测试的蛋白酶和淀粉酶没有抑制活性。氨基酸序列如下：Ile-Thr-Cys-Gly-Gln-Val-Asn-Ser-Ala-Val(10)-Gly-Pro-Cys-Leu-Thr-Tyr- Ala-Arg-Gly-Gly(20)-Ala-Gly-Pro-Ser-Ala-Ala-Cys-Cys-Ser-Gly(30)-Val-Arg- Ser-Leu-Lys-Ala-Ala-Ala-Ser-Thr(40)-Thr-Ala-Asp-Arg-Arg-Thr-Ala-Cys- Asn-Cys(50)-Leu-Lys-Asn-Ala-Ala-Arg-Gly-Ile-Lys-Gly(60)-Leu-Asn-Ala-Gly- Asn-Ala-Ala-Ser-Ile-Pro(70)-Ser-Lys-Cys-Gly-Val-Ser-Val-Pro-Tyr-Thr(80)- Ile-Ser-Ala-Ser-Ile-Asp-Cys-Ser-Arg-Val-Ser(91)。