Functional Gene Expression in Shark Bay Hypersaline Microbial Mats: Adaptive Responses

Microbial mats in Shark Bay, Western Australia, exhibit strong adaptive responses to hypersaline conditions, with gene transcription influenced by community structure and seasonality. The study reveals that these mats prioritize nutrient uptake—particularly fatty acids, phosphorus, iron, and nickel—and employ protective mechanisms against salinity and ammonium buildup. Key pathways for carbon cycling include anoxygenic photosynthesis and chemoautotrophy via the Arnon-Buchanan cycle, while smooth mats show enrichment in anaerobic processes like sulfate reduction and methanogenesis, reinforcing their role as modern analogs to ancient microbialites. This first metatranscriptomic analysis of actively growing hypersaline mats provides insights into their metabolic resilience and ecological significance.

Campbell, M. A., Grice, K., Visscher, P. T., Morris, T., Wong, H. L., White, R. A., Burns, B. P., & Coolen, M. J. L. (2020). Functional Gene Expression in Shark Bay Hypersaline Microbial Mats: Adaptive Responses. Frontiers in Microbiology, 11. https://doi.org/10.3389/fmicb.2020.560336