延长因子Tu突变扩大了蛋白质生物合成系统的氨基酸耐受性
Yoshio Doi1, Takashi Ohtsuki, Yoshihiro Shimizu
1Department of Bioscience and Biotechnology, Okayama University, Okayama, Japan.
Journal of the American Chemical Society
|October 26, 2007
概括
研究人员设计了延长因子Tu (EF-Tu),以改善大型非天然氨基酸的纳入蛋白质. 这一进步扩大了蛋白质生物合成的非自然突变发生能力.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 合成生物学 合成生物学
背景情况:
- 扩展的蛋白质生物合成系统可以将非自然氨基酸引入蛋白质中.
- 有效地纳入非天然氨基酸,特别是具有大量芳香基的氨基酸,仍然是一个挑战.
- 氨基化tRNA与延长因子Tu (EF-Tu) 的结合效率有限,阻碍了大量氨基酸的结合.
研究的目的:
- 克服EF-Tu在纳入大型非天然氨基酸方面的局限性.
- 提高非自然突变发生在蛋白质工程中的实用性.
- 扩大可用于蛋白质生物合成的氨基酸库.
主要方法:
- 来自大肠杆菌的工程延长因子Tu (EF-Tu) 通过为氨基酸tRNA制造具有扩大结合口袋的突变物.
- 合成的EF-Tu突变,旨在容纳更大的氨基酸部分.
- 使用工程 EF-Tu 变体测试了特定非天然氨基酸的整合效率.
主要成果:
- 工程 EF-Tu 突变物成功地结合了非自然氨基酸,包括 L-1-pyrenylalanine,L-2-pyrenylalanine 和 DL-2-anthraquinonylalanine.
- 这些氨基酸被野生类型的EF-Tu.很少纳入.
- 突变EF-Tu的扩大结合口袋有助于接受重的氨基-tRNAs.
结论:
- 突变EF-Tu扩大了可以纳入蛋白质的非天然氨基酸的范围.
- 这种工程 EF-Tu 系统增强了非自然突变发生的能力.
- 这些发现有助于推进蛋白质生物合成和工程.
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