人酪酪肽及其衍生物的克隆、表达及活性测定  

Cloning,Expression and Biological Activity Study of Human Peptide Tyrosine Tyrosine and Its Derivative

作　　者：王小溪[1] 李娟[1] 劳勋[1] 张洪丹[1] 黄静[1] 吴自荣[1] 

机构地区：[1]华东师范大学生命科学学院,上海200062

出　　处：《中国生物工程杂志》2011年第2期7-11,共5页China Biotechnology

摘　　要：酪酪肽(peptide tyrosine tyrosine,PYY)是存在于机体肠道的肽类激素,有PYY1-36和PYY3-36两种形式,后者可以降低个体食欲并减少食物摄入。分别通过人工合成基因和PCR定点突变的方法,得到PYY3-36衍生物PYY3-36-G ly37及PYY3-36的基因,然后克隆到pET32a(+)表达载体中,转化大肠杆菌并进行诱导表达。通过亲和层析得到融合蛋白,经肠激酶酶切和二次亲和层析得到目的多肽。在昆明鼠体内检测二者生物活性,结果显示剂量为800μg/kg时PYY3-36及PYY3-36-G ly37均可抑制昆明鼠的摄食,且抑制作用可达9h,而PYY3-36-G ly37组的平均抑制率可达50%,明显高于PYY3-36。Peptide tyrosine tyrosine （PYY） is a 36 amino-acid peptide secreted from L-cells predominantly within the distal gastrointestinal tract. Two main endogenous forms of PYY have been identified, PYY1-36 and PYY3-36. The latter has an effect of anorexia and can inhibit food intake in rodent animals. Peripheral administration of PYY3-36 can reduce food intake and body weight gain. All PYY3-36 reported were chemically synthesized. Gene cloning of PYY3-36 will be an innovation. PYY3.36gene and its derivative that were obtained by site-directed mutagenesis and artificial synthesis respectively were cloned into pET32a（ ＋ ） vector. Recombinant plasmids were expressed in Escherichia coll. Fusion proteins were purified by Ni ion affinity chromatography. Purified fusion proteins were then digested by enterokinase and purified by another affinity chromatography to get the target peptides. The biological activities of PYY3-36 and PYY3-36-Gly37 were studied in vivo in Kunming mice. The result showed that when administrated at a dose of 800μg/kg intraperitoneally, both PYY3-36 and PYY3-36- Gly37 can reduce food intake within 9 hours. Interestingly, the inhibition ratio of PYY3-36-Gly37 can reach to 50%, which is obviously higher than that of PYY3-36.

关 键 词：酪酪肽 原核表达 生物活性 

分 类 号：Q819[生物学—生物工程]