甲状旁腺激素原：放射性胰蛋白酶肽分析及氨基酸序列分析

Pre-proparathyroid hormone: analysis of radioactive tryptic peptides and amino acid sequence.

作者信息

Kemper B, Habener J F, Ernst M D, Potts J T, Rich A

出版信息

Biochemistry. 1976 Jan 13;15(1):15-9. doi: 10.1021/bi00646a003.

Abstract

The amino acid sequence of bovine pre-proparathyroid hormone has been partially determined by analysis of the polypeptide labeled selectively with radioactive amino acids. Analysis of tryptic peptides containing methionine or lysine indicated that parathyroid hormone, proparathyroid hormone, and pre-proparathyroid hormone had several common peptides. Two lysine-containing peptides present in proparathyroid hormone but not in parathyroid hormone were also present in pre-proparathyroid hormone. In addition, pre-proparathyroid hormone contained several additional lysine- and methionine-containing peptides not present in parathyroid hormone or proparathyroid hormone. Analysis by repetitive Edman degradation of the polypeptide labeled with lysine, methionine, and other amino acids indicated that pre-proparathyroid hormone contained 25 additional amino acids at the amino terminus of proparathyroid hormone; the identities of 17 of the 25 amino acids have been established. An unusual feature found was the presence of methionyl-methionyl at the amino terminus and the presence of 5 methionines within the first 14 amino acids.

摘要

通过对用放射性氨基酸选择性标记的多肽进行分析，已部分确定了牛甲状旁腺激素原前体的氨基酸序列。对含甲硫氨酸或赖氨酸的胰蛋白酶肽段的分析表明，甲状旁腺激素、甲状旁腺激素原和甲状旁腺激素原前体有几种共同的肽段。甲状旁腺激素原中存在但甲状旁腺激素中不存在的两个含赖氨酸的肽段也存在于甲状旁腺激素原前体中。此外，甲状旁腺激素原前体还含有一些甲状旁腺激素或甲状旁腺激素原中不存在的额外的含赖氨酸和甲硫氨酸的肽段。对用赖氨酸、甲硫氨酸和其他氨基酸标记的多肽进行重复埃德曼降解分析表明，甲状旁腺激素原前体在甲状旁腺激素原的氨基末端含有另外25个氨基酸；已确定了这25个氨基酸中17个的身份。发现一个不寻常的特征是在氨基末端存在甲硫氨酰-甲硫氨酰，并且在前14个氨基酸中有5个甲硫氨酸。