Abstract—Spore-forming bacteria have a unique resistance to negative environmental conditions, including aggressive space factors, and are an excellent model for studying adaptation mechanisms and survival strategies at the molecular level. The study analyzed the genome of Bacillus velezensis, which remained viable after a 2-year exposure in outer space on the outer surface of the ISS as part of the Test space experiment. A comparative analysis of the draft genomes of the exhibit strain and the ground control did not reveal significant changes; the average nucleotide identity was 99.98%, which indicates the ability of microorganisms to maintain genome stability in space conditions, due to both increased stress resistance of bacterial spores and efficient operation of the system of repair of accumulated changes. The study of a single nucleotide polymorphism in the genome of B. velezensis revealed nine point substitutions, three of which are in intergenic regions, six in protein-coding genes, three of them are missense mutations, two nucleotide deletions leading to a shift in the reading frame, and one synonymous substitution. The profiles of the housekeeping genes were determined during MLST typing and it was found that the allelic profiles obtained for B. velezensis T15.2 and 924 strains do not correspond to any of the previously described sequence types.The presented results indicate the ability of B. velezensis bacteria to maintain the viability of spores and the integrity of the genome for a long time under extreme conditions of outer space, which is important for the problem of planetary protection, as well as the potential possibility of performing biotechnological processes based on B. velezensis during space exploration.

摘要：孢子形成细菌对负面环境条件（包括侵袭性空间因素）具有独特的抵抗力，是在分子水平上研究适应机制和生存策略的优秀模型。该研究分析了贝莱斯芽孢杆菌的基因组，作为测试空间实验的一部分，该芽孢杆菌在国际空间站外表面暴露两年后仍然存活。对展示菌株和地面对照的基因组草图进行比较分析，没有发现显着变化；平均核苷酸同一性为99.98%，这表明微生物在太空条件下维持基因组稳定性的能力，这归因于细菌孢子抗逆性的增强和累积变化修复系统的有效运行。对贝莱斯巴氏杆菌基因组中单核苷酸多态性的研究揭示了九个点替换，其中三个在基因间区域，六个在蛋白质编码基因中，其中三个是错义突变，两个核苷酸缺失导致了基因组的转变。阅读框架和一个同义替换。在 MLST 分型过程中确定了管家基因的概况，发现为B. velezensis T15.2 和 924 菌株获得的等位基因概况与之前描述的任何序列类型都不对应。所呈现的结果表明B. velezensis T15.2 和 924 菌株的等位基因概况不对应于任何先前描述的序列类型。贝莱斯细菌能够在外太空极端条件下长时间保持孢子的活力和基因组的完整性，这对于行星保护问题以及基于贝莱斯细菌进行生物技术过程的潜在可能性非常重要。太空探索期间的贝莱森西斯。