通过代变异和计算设计优化终端脱氧核类转移酶的表达和热稳定性
Ilya Nikiteev1, Julia Kuzmina2, Irina Rog2
1Research Institute of System Biology and Medicine, Moscow, 117246, Russia. nikiteev.ilya@mail.ru.
Applied biochemistry and biotechnology
|January 15, 2026
概括
研究人员使用突变发生学设计了一种更稳定的终端脱核样转移酶 (TdT) 酶. 这种增强的TdT酶显著改善了热稳定性和活性,这对于推进酶性DNA合成技术至关重要.
科学领域:
- 生物化学 生化学
- 分子生物学分子生物学
- 蛋白质工程是指蛋白质工程.
背景情况:
- 终端脱核样转移酶 (TdT) 对于酶性DNA合成至关重要,但由于热稳定性不佳而受到限制.
- 提高TdT的热稳定性是开发先进的DNA合成技术的关键.
研究的目的:
- 为了提高肌肉肌肉TdT的热稳定性,使用位点和突变性和理性设计.
- 为下一代酶性DNA合成创建强大的TdT变体.
主要方法:
- 使用B因子分析和B-FITTER鉴定出用于突变发生的残留物.
- 用Foldit,ProteinMPNN和CARBonAra来选择合理设计的替代品.
- 采用代的突变发生过程来设计TdT变体.
主要成果:
- 开发了两个有前途的变种:A4 (26倍更高的表达) 和突变275 (特殊的稳定性).
- 突变275的稳定性增加了120倍 (在45°C下180分钟,而在WT下<2分钟),化温度提高了6.5°C.
- 突变者275在37°C时表现出4至6倍增加的催化活性.
- 突变者275的增强稳定性归因于表面盐桥网络.
结论:
- 成功设计了具有高热稳定的TdT变体,其活性得到改善.
- 这些变体是对酶性DNA合成进一步工程的有希望的支架.
- 这项研究克服了用于DNA合成的TdT应用的主要局限性.
相关概念视频
Translesion DNA Polymerases
11.0K
Translesion (TLS) polymerases rescue stalled DNA polymerases at sites of damaged bases by replacing the replicative polymerase and installing a nucleotide across the damaged site. Doing so, TLS allows additional time for the cell to repair the damage before resuming regular DNA replication.
TLS polymerases are found in all three domains of life - archaea, bacteria, and eukaryotes. Of the different classes of TLS polymerases, members of the Y family are fitted with specialized structures that...
TLS polymerases are found in all three domains of life - archaea, bacteria, and eukaryotes. Of the different classes of TLS polymerases, members of the Y family are fitted with specialized structures that...
11.0K
Conservative Site-specific Recombination and Phase Variation
6.7K
Because the DNA segments are cut and reorganized in a direction-specific manner, site-specific recombination has emerged as an efficient genetic engineering technique. Flippase and Cyclization recombinases or Flp and Cre, respectively, are two members of the tyrosine recombinase family derived from bacteriophages, that are used to mediate site-specific DNA insertions, deletions, and targeted expression of proteins in mammalian cell lines.
The recognition sites for Cre recombinase called LoxP...
The recognition sites for Cre recombinase called LoxP...
6.7K
Improving Translational Accuracy
14.1K
Base complementarity between the three base pairs of mRNA codon and the tRNA anticodon is not a failsafe mechanism. Inaccuracies can range from a single mismatch to no correct base pairing at all. The free energy difference between the correct and nearly correct base pairs can be as small as 3 kcal/ mol. With complementarity being the only proofreading step, the estimated error frequency would be one wrong amino acid in every 100 amino acids incorporated. However, error frequencies observed in...
14.1K


