The Space-Exposed Kombucha Microbial Community Member Komagataeibacter oboediens Showed Only Minor Changes in Its Genome After Reactivation on Earth

Abstract

Komagataeibacter is the dominant taxon and cellulose-producing bacteria in the Kombucha Microbial Community (KMC). This is the first study to isolate the K. oboediens genome from a reactivated space-exposed KMC sample and comprehensively characterize it. The space-exposed genome was compared with the Earth-based reference genome to understand the genome stability of K. oboediens under extraterrestrial conditions during a long time. Our results suggest that the genomes of K. oboediens IMBG180 (ground sample) and K. oboediens IMBG185 (space-exposed) are remarkably similar in topology, genomic islands, transposases, prion-like proteins, and number of plasmids and CRISPR-Cas cassettes. Nonetheless, there was a difference in the length of plasmids and the location of cas genes. A small difference was observed in the number of protein coding genes. Despite these differences, they do not affect any genetic metabolic profile of the cellulose synthesis, nitrogen-fixation, hopanoid lipids biosynthesis, and stress-related pathways. Minor changes are only observed in central carbohydrate and energy metabolism pathways gene numbers or sequence completeness. Altogether, these findings suggest that K. oboediens maintains its genome stability and functionality in KMC exposed to the space environment most probably due to the protective role of the KMC biofilm. Furthermore, due to its unaffected metabolic pathways, this bacterial species may also retain some promising potential for space applications.

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“…In the genome of K. oboediens IMBG180, a key bacterium of the KMC IMBG-1, islands of symbiosis and metabolic and virulence islands were found. However, they defected with any genes lost [78]. Again, the Rho transcription terminator gene was detected for prion-like proteins, but the Rho cPrD (prion-forming) domain was not found in the IMBG180 genome.…”

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“…Проєкти з космічної біології в Україні: сучасні тенденції теріями роду Komagataeibacter, та експресії генів, пов'язаних з її біосинтезом після тривалого впливу космічних/марсоподібних стресорів [14,21,46,52,67]. Оскільки виробництво целюлози за допомогою чайного гриба є безвідходним, автори обговорюють його принадність для БСЖ [46,67].…”

Komagataeibacter oboediens changes outer membrane vesicle-associated activities after exposure on the International Space Station

“…Strains of K. oboediens IMBG180 isolated from reference ground-based KMC specimens, K. oboediens IMBG185 -from UV-irradiated top-located KMC, K. hansenii IMBG183from UV-protected bottom-located KMC and K. hansenii IMBG184 -from a protected middle-located KMC on the ISS [22]. These strains were cultured in HS medium [23] at 28 °C for three days for OMVs isolation.…”

“…To determine the genetic basis of extracellular DNase/ RNase activities of K. oboediens, we sequenced and assembled genomes of both reference and spaceflight-related isolates [22]. The genomes were found with minor diffe ren ces, despite the exposure to stressful factors.…”