Vitreous Magnesium Sulfate Hydrate as a Potential Mechanism for Preservation of Microbial Viability on Europa

Author:

Parker Ceth W.ORCID,Vu Tuan H.ORCID,Kim TaewooORCID,Johnson Paul V.ORCID

Abstract

Abstract Europa's subsurface ocean is postulated to contain appreciable amounts of Mg2+ and SO 4 2 ions, among other species. Recent laboratory experiments have shown that when solutions containing these species freeze to Europa-relevant temperatures, they can form vitreous MgSO4 hydrate, which can remain stable at these temperatures. Since vitreous phases can protect cells from physical damage that can occur during crystallization, their presence on Europa could potentially preserve entrained microorganisms from the ocean below. However, to date, it remains unclear whether such materials actually impact microbial survival. In this work, experiments were performed in which the motile nonspore-forming Antarctic isolate Pseudoalteromonas haloplanktis in solutions of 0.1 M MgSO4 were frozen to Europa surface temperatures (100 K) under conditions that resulted in the formation of either vitreous or crystalline salt hydrates. We found that cells survived in both cases, exhibiting a 3-log reduction in viable cells in the crystalline salt hydrate case while only a 1.5-log reduction in the vitreous salt hydrate case. Scanning electron microscopy accordingly showed much higher degrees of membrane lysis and cellular damage in the crystalline salt hydrate than the vitreous case. Our results demonstrate the ability of a terrestrial oceanic microorganism to survive in MgSO4 solutions frozen to Europa surface temperatures, with enhanced viability in vitreous salt-hydrate-producing conditions versus crystalline. These findings suggest that future missions should target vitrified salt-rich environments for life detection due to this potential for preserving viable microorganisms that may be present and trapped in ocean world ices.

Funder

NASA ∣ Jet Propulsion Laboratory

Publisher

American Astronomical Society

Subject

Space and Planetary Science,Earth and Planetary Sciences (miscellaneous),Geophysics,Astronomy and Astrophysics

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3