Building a Geochemical View of Microbial Salt Tolerance: Halophilic Adaptation of Marinococcus in a Natural Magnesium Sulfate Brine.
Building a Geochemical View of Microbial Salt Tolerance: Halophilic Adaptation of Marinococcus in a Natural Magnesium Sulfate Brine.
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DOI：
10.3389/fmicb.2018.00739
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发表时间：
2018
影响因子：
5.2
通讯作者：
Cockell CS
中科院分区：
文献类型：
--
作者：
Fox-Powell MG;Cockell CS
目前对高盐生境中生命的认识主要局限于钠和氯化物为主的环境。这个狭窄的成分窗口并不能反映地球和其他行星上自然存在的盐水环境的多样性。了解微生物生物圈的极限和预测地外可居住性需要系统的努力来表征具有代表性的盐水栖息地的生物的离子特异性。在这里，我们研究了从镁和硫酸盐为主的巴斯克湖（不列颠哥伦比亚省，加拿大）分离的一株马里诺球菌。这种生物是暴露于异常高水平的Mg2+和SO42-离子（分别为2.369和2.840 M）后获得的唯一分离物，并在Na+/Cl-盐水（12.141 mol l- 1）中通常不会遇到的极端离子强度下生长。它在16S rDNA水平上与嗜盐细菌的联系表明，祖先的嗜盐性使它能够适应不同的含盐栖息地。在以NaCl、Na2SO4、MgCl2和MgSO4为主的培养基中，菌株表现出生长，但尽管有这种可塑性，菌株仍然受到限制；需要Na+或Cl-维持较短的倍增时间。水活度不能解释培养基之间的生长速率差异，这表明离子组成对决定微生物生长窗口的重要性。我们需要一个新的框架来理解盐水中的生长，这个框架既要解释盐水的地球化学历史，也要解释离子对微生物施加的各种压力。需要这样的研究来获得对生物离子耐受极限的真正普遍理解。
Current knowledge of life in hypersaline habitats is mostly limited to sodium and chloride-dominated environments. This narrow compositional window does not reflect the diversity of brine environments that exist naturally on Earth and other planetary bodies. Understanding the limits of the microbial biosphere and predicting extraterrestrial habitability demands a systematic effort to characterize ionic specificities of organisms from a representative range of saline habitats. Here, we investigated a strain of Marinococcus isolated from the magnesium and sulfate-dominated Basque Lakes (British Columbia, Canada). This organism was the sole isolate obtained after exposure to exceptionally high levels of Mg2+ and SO42- ions (2.369 and 2.840 M, respectively), and grew at extremes of ionic strength not normally encountered in Na+/Cl- brines (12.141 mol liter-1). Its association at the 16S rDNA level with bacterial halophiles suggests that ancestral halophily has allowed it to adapt to a different saline habitat. Growth was demonstrated in media dominated by NaCl, Na2SO4, MgCl2, and MgSO4, yet despite this plasticity the strain was still restricted; requiring either Na+ or Cl- to maintain short doubling times. Water activity could not explain growth rate differences between media, demonstrating the importance of ionic composition for dictating microbial growth windows. A new framework for understanding growth in brines is required, that accounts for the geochemical history of brines as well as the various stresses that ions impose on microbes. Studies such as this are required to gain a truly universal understanding of the limits of biological ion tolerance.
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影响因子：
1.2
作者：
HAO, MV;KOCUR, M;KOMAGATA, K
通讯作者：
KOMAGATA, K
影响因子：
5.8
作者：
Hynek, Brian M.;Osterloo, Mikki K.;Kierein-Young, Kathryn S.
通讯作者：
Kierein-Young, Kathryn S.
影响因子：
2.8
作者：
ABRAM, D;GIBBONS, NE
通讯作者：
GIBBONS, NE
影响因子：
5.1
作者：
Hallsworth, John E.;Yakimov, Michail M.;McGenity, Terry J.
通讯作者：
McGenity, Terry J.
DOI：
10.1186/2046-9063-8-4
发表时间：
2012-02-02
期刊：
Aquatic biosystems
影响因子：
--
作者：
Karan R;Capes MD;Dassarma S
通讯作者：
Dassarma S