Rennex D, Hemmings B A, Hofsteenge J, Stone S R
Friedrich Miescher-Institut, Basel, Switzerland.
Biochemistry. 1991 Feb 26;30(8):2195-203. doi: 10.1021/bi00222a025.
Prolyl endopeptidase is a cytoplasmic serine protease. The enzyme was purified from porcine kidney, and oligonucleotides based on peptide sequences from this protein were used to isolate a cDNA clone from a porcine brain library. This clone contained the complete coding sequence of prolyl endopeptidase and encoded a polypeptide with a molecular mass of 80,751 Da. The deduced amino acid sequence of prolyl endopeptidase showed no sequence homology with other known serine proteases. [3H]Diisopropyl fluorophosphate was used to identify the active-site serine of prolyl endopeptidase. One labeled peptide was isolated and sequenced. The sequence surrounding the active-site serine was Asn-Gly-Gly-Ser-Asn-Gly-Gly. This sequence is different from the active-site sequences of other known serine proteases. This difference and the lack of overall homology with the known families of serine proteases suggest that prolyl endopeptidase represents a new type of serine protease.
脯氨酰内肽酶是一种胞质丝氨酸蛋白酶。该酶从猪肾中纯化得到，基于该蛋白质的肽序列合成的寡核苷酸被用于从猪脑文库中分离出一个cDNA克隆。这个克隆包含脯氨酰内肽酶的完整编码序列，编码一个分子量为80,751道尔顿的多肽。推导得到的脯氨酰内肽酶氨基酸序列与其他已知丝氨酸蛋白酶没有序列同源性。[3H]二异丙基氟磷酸被用于鉴定脯氨酰内肽酶的活性位点丝氨酸。分离出一个标记肽并进行测序。活性位点丝氨酸周围的序列是天冬酰胺-甘氨酸-甘氨酸-丝氨酸-天冬酰胺-甘氨酸-甘氨酸。这个序列与其他已知丝氨酸蛋白酶的活性位点序列不同。这种差异以及与已知丝氨酸蛋白酶家族缺乏整体同源性表明脯氨酰内肽酶代表一种新型的丝氨酸蛋白酶。
