Drought re-routes soil microbial carbon metabolism towards emission of volatile metabolites in an artificial tropical rainforest
Linnea K. Honeker, Giovanni Pugliese, Johannes Ingrisch, Jane Fudyma, Juliana Gil-Loaiza, Elizabeth Carpenter, Esther Singer, Gina Hildebrand, Lingling Shi, David W. Hoyt, Rosalie K. Chu, Jason Toyoda, Jordan E. Krechmer, Megan S. Claflin, Christian Ayala-Ortiz, Viviana Freire-Zapata, Eva Y. Pfannerstill, L. Erik Daber, Kathiravan Meeran, Michaela A. Dippold, Jürgen Kreuzwieser, Jonathan Williams, S. Nemiah Ladd, Christiane Werner, Malak M. Tfaily & Laura K. Meredith
Nature Microbiology
Nat Microbiol 8, 1480–1494 (2023)
Publication Date: July 31, 2023
Copyright © 2023, The Author(s)
Open Access
This work is distributed under the Creative Commons Attribution 4.0 International License
Abstract.
Drought impacts on microbial activity can alter soil carbon fate and lead to the loss of stored carbon to the atmosphere as CO2 and volatile organic compounds (VOCs). Here we examined drought impacts on carbon allocation by soil microbes in the Biosphere 2 artificial tropical rainforest by tracking 13C from position-specific 13C-pyruvate into CO2 and VOCs in parallel with multi-omics. During drought, efflux of 13C-enriched acetate, acetone and C4H6O2 (diacetyl) increased. These changes represent increased production and buildup of intermediate metabolites driven by decreased carbon cycling efficiency. Simultaneously,13C-CO2 efflux decreased, driven by a decrease in microbial activity. However, the microbial carbon allocation to energy gain relative to biosynthesis was unchanged, signifying maintained energy demand for biosynthesis of VOCs and other drought-stress-induced pathways. Overall, while carbon loss to the atmosphere via CO2 decreased during drought, carbon loss via efflux of VOCs increased, indicating microbially induced shifts in soil carbon fate.