在火星恶劣的地下条件下的细菌模型膜
Attila Tortorella1,2, Rosario Oliva2, Concetta Giancola3
1Scuola Superiore Meridionale (SSM), Via Mezzocannone 4, 80138, Naples, Italy.
Physical chemistry chemical physics : PCCP
|October 20, 2023
概括
细菌膜在高压和火星相关盐,特别是酸盐下保持液态. 这表明生命可以在极端的火星地下环境中持续存在.
科学领域:
- 天体生物学 天体生物学
- 生物物理学的生物物理.
- 环境科学 环境科学
背景情况:
- 生物膜对生命至关重要,但它们在极端条件下的行为,如火星上的情况,人们对其了解甚少.
- 火星地下可能含有高度的热带盐,并经历高水静压,影响膜的稳定性和功能.
- 研究这些条件对于评估外星人的可居住性至关重要.
研究的目的:
- 为了检查火星相关盐 (酸盐和硫酸盐) 和高水静压对细菌模型膜的联合作用.
- 为了确定不同的盐成分 (Na+与Mg2+对应物) 如何影响压力下的膜特性.
- 在模拟的火星条件下,评估对膜内的酶活性的影响.
主要方法:
- 利用生物物理技术,包括热度计,光和CD光谱,共聚焦显微镜和小角度X射线散射.
- 研究了细菌模型膜的稳定性,结构和功能.
- 在不同的盐和压力条件下测量了脂酶A2的活性.
主要成果:
- 硫酸盐和酸盐根据对应物 (Na+与Mg2+) 不同地影响膜性质.
- 甲酸盐促进更水合,更少的秩序,类似流体的膜阶段,即使在高压下.
- 脂酶A2的活性受到高压和盐度的显著调节,但在甲酸盐的存在下仍然是可行的.
结论:
- 细菌膜可以在模拟的火星地下条件下保持功能性流体状状态.
- 即使在凝结Mg2+和高压的情况下,混类酸盐的存在也支持膜功能和酶活性.
- 这些发现表明,细菌生命可能会在火星地下的极端环境中持续存在.
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