Adaptive mechanisms of Bacillus to near space extreme environments

Aihua Deng; Tiantian Wang; Junyue Wang; Lai Li; Xueliang Wang; Li Liu; Tingyi Wen

doi:10.1016/j.scitotenv.2023.163952

Adaptive mechanisms of Bacillus to near space extreme environments

Sci Total Environ. 2023 Aug 15:886:163952. doi: 10.1016/j.scitotenv.2023.163952. Epub 2023 May 8.

Authors

Aihua Deng¹, Tiantian Wang², Junyue Wang², Lai Li², Xueliang Wang², Li Liu³, Tingyi Wen⁴

Affiliations

¹ State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China. Electronic address: dengah@im.ac.cn.
² State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China.
³ University of Chinese Academy of Sciences, Beijing 100049, China; Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China.
⁴ State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; Savaid medical school, University of Chinese Academy of Sciences, Beijing 100049, China; China Innovation Academy for Green Manufacture, Chinese Academy of Sciences, Beijing, China. Electronic address: wenty@im.ac.cn.

PMID: 37164076
DOI: 10.1016/j.scitotenv.2023.163952

Abstract

Earth's near space is an extreme atmosphere environment with high levels of radiation, low atmospheric pressure and dramatic temperature fluctuations. The region is above the flight altitude of aircraft but below the orbit of satellites, which has special and Mars-like conditions for investigating the survival and evolution of life. Technical limitations including flight devices, payloads and technologies/methodologies hinder microbiological research in near space. In this study, we investigated microbial survival and adaptive strategies in near space using a scientific balloon fight mission and multi-omics analyses. Methods for sample preparation, storage, protector and vessel were optimized to prepare the exposed microbial samples. After 3 h 17 min of exposure at a float altitude of ~32 km, only Bacillus strains were alive with survival efficiencies of 0-10^-6. Diverse mutants with significantly altered metabolites were generated, firstly proving that Earth's near space could be used as a new powerful microbial breeding platform. Multi-omics analyses of mutants revealed cascade changes at the genome, transcriptome and proteome levels. In response to environmental stresses, two mutants had similar proteome changes caused by different genomic mutations and mRNA expression levels. Metabolic network analysis combined with proteins' expression levels revealed that metabolic fluxes of EMP, PPP and purine synthesis-related pathways were significantly altered to increase/decrease inosine production. Further analysis showed that proteins related to translation, molecular chaperones, cell wall/membrane, sporulation, DNA replication/repair and anti-oxidation were significantly upregulated, enabling cells to efficiently repair DNA/protein damages and improve viability against environmental stress. Overall, these results revealed genetic and metabolic responses of Bacillus to the harsh conditions in near space, providing a research basis for bacterial adaptive mechanisms in extreme environments.

Keywords: Adaptive mechanism; Bacillus; Genome; Near space; Proteome; Transcriptome.

MeSH terms

Atmosphere
Bacillus* / physiology
Bacteria
Extreme Environments
Proteome

Substances

Proteome