A Cold-Induced LEA3 Protein, DohD, Confers Cryoprotective Protection Against Low-Temperature Stress in Deinococcus radiodurans

文献类型： 外文期刊

第一作者： Wang, Wenxiu

作者： Wang, Wenxiu;Zhou, Zhengfu;Wang, Jin;Wang, Wenxiu;Qi, Zhi;Yan, Chunxia

作者机构：

关键词： Deinococcus radiodurans; low-temperature stress; DohD; cold-induced protein; LEA3

期刊名称：INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES （ 影响因子：4.9； 五年影响因子：5.7 ）

ISSN： 1661-6596

年卷期： 2025 年 26 卷 8 期

页码：

收录情况： SCI

摘要： Deinococcus radiodurans is a remarkably unique microorganism, exhibiting extraordinary tolerance to extreme conditions such as ionizing radiation, ultraviolet light, and desiccation. However, the response mechanisms of D. radiodurans under low-temperature stress remain largely unexplored and have yet to be fully elucidated. The DohD protein is a hydrophilic member of the late embryogenesis abundant 3 (LEA3) family of D. radiodurans, playing a pivotal role in abiotic stress adaptation. Bioinformatics analysis revealed that DohD contains tandem repeats and disordered domains, with a remarkably high alpha-helix content (91.41%). Furthermore, DohD exhibits extremely low homology with other proteins, highlighting its uniqueness to D. radiodurans. Under low-temperature stress (15 degrees C), the expression of dohD was significantly upregulated (5-fold), regulated by a dual mechanism involving positive control by DrRRA and negative regulation by Csp. Circular dichroism spectroscopy unveiled temperature-dependent structural plasticity: as the temperature increased from 0 degrees C to 50 degrees C, the alpha-helix content decreased from 23.5% to 18.7%, while the antiparallel beta-sheet content increased from 31.3% to 50.8%. This suggests an alpha-helix to beta-sheet interconversion mechanism as a strategy for thermal adaptation. Additionally, deletion of dohD impaired the tolerance of D. radiodurans to cold, desiccation, oxidative, and high-salt stresses, accompanied by the reduced activities of antioxidant enzymes (SOD, CAT, POD) and the downregulation of related gene expression. This study elucidates the multifunctional role of DohD in stress resistance through structural dynamics, transcriptional regulation, and redox homeostasis, providing valuable insights into the adaptation mechanisms of extremophiles.

分类号：

  • 相关文献
作者其他论文 更多>>

微信小程序