Wang Qi, Wang Zhiwei, Guan Jiaqi, Song Jinzhu
School of Life Science and Technology, Harbin Institute of Technology, Harbin 150080, China.
Int J Mol Sci. 2024 Apr 10;25(8):4168. doi: 10.3390/ijms25084168.
JX313 is an extremely halophilic archaea that can grow in a NaCl-saturated environment. The excellent salt tolerance of makes it a high-potential candidate for researching the salt stress mechanisms of halophilic microorganisms from . In this study, transcriptome analysis revealed that three genes related to the biosynthesis of vitamin B were upregulated in response to salt stress. For the wild-type (WT) strain JX313, the low-salt adaptive mutant LND5, and the vitamin B synthesis-deficient strain Δ, the exogenous addition of 10 mg/L of vitamin B could maximize their cell survival and biomass in both optimal and salt stress environments. Knockout of resulted in changes in the growth boundary of the strain, as well as a significant decrease in cell survival and biomass, and the inability to synthesize vitamin B. According to the HPLC analysis, when the external NaCl concentration (/) increased from 17.5% (optimal) to 22.5% (5% salt stress), the intracellular accumulation of vitamin B in WT increased significantly from (11.54 ± 0.44) mg/L to (15.23 ± 0.20) mg/L. In summary, is capable of absorbing or synthesizing vitamin B in response to salt stress, suggesting that vitamin B serves as a specific compatible solute effector for during salt stress.
JX313是一种极端嗜盐古菌，能够在NaCl饱和环境中生长。其出色的耐盐性使其成为研究嗜盐微生物盐胁迫机制的极具潜力的候选对象。在本研究中，转录组分析表明，与维生素B生物合成相关的三个基因在盐胁迫响应中上调。对于野生型（WT）菌株JX313、低盐适应性突变体LND5和维生素B合成缺陷菌株Δ，外源添加10 mg/L的维生素B可在最佳和盐胁迫环境中使它们的细胞存活率和生物量最大化。基因敲除导致菌株生长边界发生变化，细胞存活率和生物量显著降低，并无法合成维生素B。根据高效液相色谱分析，当外部NaCl浓度（/）从17.5%（最佳）增加到22.5%（5%盐胁迫）时，野生型细胞内维生素B的积累量从（11.54±0.44）mg/L显著增加到（15.23±0.20）mg/L。总之，JX313能够在盐胁迫响应中吸收或合成维生素B，这表明维生素B在盐胁迫期间作为JX313的一种特定相容性溶质效应物。
