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Xerotolerance: A New Property in Exiguobacterium Genus
María Castillo López1,2, Beatriz Galán1, Manuel Carmona1
1Microbial and Plant Biotechnology Department, Centro de Investigaciones Biológicas Margarita Salas-CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain.
Microorganisms
|December 24, 2021
Summary
A novel xerotolerant bacterium, Exiguobacterium sp. Helios, exhibits remarkable desiccation resistance, surpassing even Deinococcus radiodurans. This discovery opens avenues for biotechnological applications and understanding microbial extremophiles.
Area of Science:
- Microbiology
- Extremophile Research
- Biotechnology
Background:
- Exiguobacterium genus is known for its diversity but not xerotolerance.
- A novel Exiguobacterium sp. Helios strain was isolated from a solar panel.
- This strain shows a close relationship to Exiguobacterium sibiricum from permafrost.
Purpose of the Study:
- To characterize the xerotolerance of Exiguobacterium sp. Helios.
- To investigate the role of cell surface structures in desiccation resistance.
- To explore biotechnological applications of this polyextremophilic strain.
Main Methods:
- Comparative analysis of Exiguobacterium sp. Helios and E. sibiricum 255-15.
- Observation of cell morphology changes after desiccation.
- Development of a genetic transformation protocol for Exiguobacterium sp. Helios.
Main Results:
- Exiguobacterium sp. Helios demonstrates higher xerotolerance than Deinococcus radiodurans.
- Cell surface morphology changes significantly upon desiccation, indicating its role in tolerance.
- Selenium nanoparticles are produced by Exiguobacterium sp. Helios in the presence of selenite.
- The first genetic modification of an Exiguobacterium species was achieved.
Conclusions:
- Exiguobacterium sp. Helios is a highly xerotolerant and polyextremophilic bacterium with biotechnological potential.
- Cellular surface structure is crucial for xerotolerance in this genus.
- The presence of competence and incomplete sporulation genes suggests roles in xerotolerance and adaptation.
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