Show simple item record

dc.contributor.authorCesur, Robin M.
dc.contributor.authorAnsari, Irfan M.
dc.contributor.authorChen, Fei
dc.contributor.authorClark, Benton C.
dc.contributor.authorSchneegurt, Mark A.
dc.identifier.citationBacterial Growth in Brines Formed by the Deliquescence of Salts Relevant to Cold Arid Worlds Robin M. Cesur, Irfan M. Ansari, Fei Chen, Benton C. Clark, and Mark A. Schneegurt Astrobiology 2022 22:1, 104-115en_US
dc.descriptionClick on the DOI link to access the article (may not be free).en_US
dc.description.abstractHygroscopic salts at Mars' near-surface (MgSO4, (per)chlorates, NaCl) may form brines by absorbing moisture from the atmosphere at certain times through the process of deliquescence. We have previously shown strong bacterial growth in saturated MgSO4 (∼67% w/v as epsomite) at room temperature, and growth was observed at the MgSO4 eutectic point (43% w/v at -4°C). Here, we have investigated the growth of salinotolerant microbes (Halomonas, Marinococcus, Planococcus) from Hot Lake, Washington; Basque Lake, British Columbia; and Great Salt Plains, Oklahoma under deliquescing conditions. Bacterial cultures were grown to mid-log phase in SP medium supplemented with 50% MgSO4 (as epsomite), 20% NaClO3, or 10% NaCl (w/v), and small aliquots in cups were dried by vacuum desiccation. When the dried culture was rehydrated by the manual addition of water, the culture resumed growth in the reconstituted brine. When desiccated cultures were maintained in a sealed container with a brine reservoir of the matching growth medium controlling the humidity of the headspace, the desiccated microbial culture evaporites formed brine by deliquescence using humidity alone. Bacterial cultures resumed growth in all three salts once rehydrated by deliquescence. Cultures of Halomonas sp. str. HL12 showed robust survival and growth when subjected to several cycles of desiccation and deliquescent or manual rehydration. Our laboratory demonstrations of microbial growth in deliquescent brines are relevant to the surface and near-subsurface of cold arid worlds like Mars. When conditions become wetter, hygroscopic evaporite minerals can deliquesce to produce the earliest habitable brines. Survival after desiccation and growth in deliquescent brines increases the likelihood that microbes from Earth, carried on spacecraft, pose a contamination risk to Mars.en_US
dc.publisherMary Ann Liebert, Inc.en_US
dc.titleBacterial growth in brines formed by the deliquescence of salts relevant to cold arid worldsen_US
dc.rights.holderCopyright 2022, Mary Ann Liebert, Inc., publishersen_US

Files in this item


There are no files associated with this item.

This item appears in the following Collection(s)

Show simple item record