The International Space Station Environment Triggers Molecular Responses in Aspergillus niger

Abstract

Due to immense phenotypic plasticity and adaptability, Aspergillus niger is a cosmopolitan fungus that thrives in versatile environments, including the International Space Station (ISS). This is the first report of genomic, proteomic, and metabolomic alterations observed in A. niger strain JSC-093350089 grown in a controlled experiment aboard the ISS. Whole-genome sequencing (WGS) revealed that ISS conditions, including microgravity and enhanced irradiation, triggered non-synonymous point mutations in specific regions, chromosomes VIII and XII of the JSC-093350089 genome when compared to the ground-grown control. Proteome analysis showed altered abundance of proteins involved in carbohydrate metabolism, stress response, and cellular amino acid and protein catabolic processes following growth aboard the ISS. Metabolome analysis further confirmed that space conditions altered molecular suite of ISS-grown A. niger JSC-093350089. After regrowing both strains on Earth, production of antioxidant—Pyranonigrin A was significantly induced in the ISS-flown, but not the ground control strain. In summary, the microgravity and enhanced irradiation triggered unique molecular responses in the A. niger JSC-093350089 suggesting adaptive responses.

Adaptation to space conditions of novel bacterial species isolated from the International Space Station revealed by functional gene annotations and comparative genome analysis

“…Clusters associated with small molecule and peptide biosynthesis in fungi were found in abundance, reaffirming earlier studies into molecular responses to microgravity [11]. The pool of novel genes unique to the ISS species (Supplementary Table S12)…”

“…Moreover, genes related to beta-mannosidase and mannose activities were up-regulated in high salinity media in the brine shrimp Artemia salina [33], suggesting that mannose and its derivatives may be accumulated as organic osmolytes. Clusters associated with small molecule and peptide biosynthesis in fungi were found in abundance, reaffirming earlier studies into molecular responses to microgravity [11]. The pool of novel genes unique to the ISS species (Supplementary Table S12) showed an abundance of genes related to peptide and small molecule synthesis, transmembrane secretion/transport, and mechanosensitive ion channels.…”

“…In addition to microorganisms potentially hitching a ride with robotic components, the microbiomes of humans also travel to space. This not only includes the microbiomes of space crew members, but also free-living microorganisms associated with cargo, science instruments, and test animals, including potential pathogens which should be considered for their potential to adapt to space conditions [8][9][10][11][12][13].…”

Pharmacogenomics Guided Spaceflight: the intersection between space-flown drugs and space genes

“…84 Across animal, plant, and fungi kingdoms, SNPs associated with spaceflight have been reported. [84][85][86] In humans particularly, space radiation left SNPs that were known to be risk alleles for neuro-ocular issues, suggesting a potential functional consequence of these SNPs. 84 In bacteria, SNPs have been associated with the development of antibiotic resistance.…”

Medical Astro-Microbiology: Current Role and Future Challenges

“… 154 , 161 Subsequent experiments comparing the same A. niger exposed to the ISS conditions against a ground control revealed that ISS conditions permanently altered the strains metabolic functions with a significant enhancement in production of the pyranonigrin A. 162 A summary of fungal pathogens with medical astro-microbiology association can be seen in Table 3 .…”