Huang Kaizong, Li Jingjing, Li Wei, Ge Huihua, Wang Wenyan, Zhang Guangya
Department of Bioengineering and Biotechnology, Huaqiao University, Xiamen 362021, China.
Sheng Wu Gong Cheng Xue Bao. 2011 Apr;27(4):653-8.
Elastin-like polypeptides (ELPs) are temperature sensitive biopolymers composed of a Val-Pro-Gly-Xaa-Gly pentapeptide repeat that derived from a structural motif found in mammalian elastin. It was a promising tag for recombinant protein purification. Here, we de novo designed a novel ELPs gene and cloned it into the modified expression vector pET-22b(+). Then, we transformed the recombinant expression vector pET-22b-ELPs into Escherichia coli BL21(DE3). Upon induction by Isopropyl beta-D-Thiogalactoside (IPTG), ELPs was expressed and purified by a non-chromatographic purification method named inverse temperature cycling. The influences of salts types and concentrations on ELPs were also determined. The results showed that the transition temperature of the [KV8F-20] decreased to 19 degrees C by 0.4 mmol/L Na2CO3. Due to its small molecular weight and sensitivity to salt, the ELPs might be a useful purification tag, which can provide a reliable and simple non-chromatographic method for purification of the recombinant protein by inverse transition cycling.
弹性蛋白样多肽（ELPs）是由缬氨酸-脯氨酸-甘氨酸-Xaa-甘氨酸五肽重复序列组成的温度敏感型生物聚合物，该重复序列源自哺乳动物弹性蛋白中的一种结构基序。它是重组蛋白纯化的一种有前景的标签。在此，我们从头设计了一个新型的ELPs基因，并将其克隆到修饰后的表达载体pET-22b(+)中。然后，我们将重组表达载体pET-22b-ELPs转化到大肠杆菌BL21(DE3)中。经异丙基-β-D-硫代半乳糖苷（IPTG）诱导后，ELPs得以表达，并通过一种名为逆温循环的非色谱纯化方法进行纯化。我们还测定了盐的类型和浓度对ELPs的影响。结果表明，0.4 mmol/L的Na2CO3可使[KV8F-20]的转变温度降至19℃。由于其分子量小且对盐敏感，ELPs可能是一种有用的纯化标签，可为通过逆转变循环纯化重组蛋白提供一种可靠且简单的非色谱方法。
