大型犬胆囊收缩素（CCK58）的部分结构：氨基酸序列

Partial structure of a large canine cholecystokinin (CCK58): amino acid sequence.

作者信息

Eysselein V E, Reeve J R, Shively J E, Hawke D, Walsh J H

出版信息

Peptides. 1982 Jul-Aug;3(4):687-91. doi: 10.1016/0196-9781(82)90171-1.

Abstract

A cholecystokinin molecule larger than any previously chemically characterized was purified from canine proximal small intestine mucosa. The purification procedure consisted of sequential steps of affinity chromatography, gel filtration, and high pressure liquid chromatography. Activity was detected and quantitated by radioimmunoassay with an antibody that recognized the carboxyl terminal sequence of porcine cholecystokinin. Microsequencing of the purified peptide revealed an amino terminal nonadecapeptide sequence (AQKVNSGEPRAHLGALLAR) not present in known cholecystokinin molecules followed by a nonadecapeptide sequence (YIQQARKAPSGRMSVIKNL) that corresponds exactly to the amino terminal sequence of porcine cholecystokinin 39 except for reversed positions of a Met and a Val residue. Based on the sequence analysis, immunoreactivity, and presence of biological activity in two bioassay systems, this peptide, tentatively named cholecystokinin 58, may be a biosynthetic precursor of the smaller forms previously characterized in gastrointestinal and brain tissues.

摘要

从犬近端小肠黏膜中纯化出一种比以往任何化学鉴定过的胆囊收缩素分子都大的分子。纯化过程包括亲和色谱、凝胶过滤和高压液相色谱的连续步骤。通过放射免疫分析法，使用识别猪胆囊收缩素羧基末端序列的抗体来检测和定量活性。对纯化肽的微量测序显示，其氨基末端有一个已知胆囊收缩素分子中不存在的十九肽序列（AQKVNSGEPRAHLGALLAR），随后是一个十九肽序列（YIQQARKAPSGRMSVIKNL），该序列除了一个甲硫氨酸和一个缬氨酸残基位置颠倒外，与猪胆囊收缩素39的氨基末端序列完全一致。基于序列分析、免疫反应性以及在两种生物测定系统中的生物活性，这种暂时命名为胆囊收缩素58的肽可能是先前在胃肠道和脑组织中鉴定出的较小形式的生物合成前体。