Chief Scientist and Laboratory Fellow Biological Sciences Division, EARTH AND BIOLOGICAL SCIENCES DIRECTORATEPacific Northwest National Laboratory Richland, Washington
Soil microorganisms carry out essential functions for life on Earth. These include support of plant growth and soil fertility and nutrient cycling. These same functions will be needed for sustainable support of life in space. Here we aimed to understand how microgravity conditions in the space environment influence the ability of soil microorganisms to interact. We studied the well characterized model soil consortium -2 (MSC-2) that is comprised of 8 bacterial species - all of which have been genome sequenced. The 8 species interact with each other during decomposition of chitin - an abundant carbon biopolymer. We used a multi-omics approach to determine what roles the different species play as they decompose chitin in soil. The combined results of the multi-omics data: amplicon sequencing, metatranscriptomics, metaproteomics and metabolomics, all revealed temporal dynamics of the MSC-2 consortium over a 3-month incubation period. Replicate experiments were performed on Earth at the Kennedy Space Center and on the International Space Station. The multi-omics data also revealed which species were carrying out specific steps in the chitin decomposition pathway. These results pave the way towards understanding of how multi-species interactions in a complex soil habitat are influenced differently in space compared to Earth.