Microbial hydrocarbon degradation in Guaymas Basin—exploring the roles and potential interactions of fungi and sulfate-reducing bacteria

© The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Edgcomb, V., Teske, A., & Mara, P. Microbial hydrocarbon degradation in Guaymas Basin—exploring the roles and potential interactions of fungi and sulfate-reducing bacteria. Frontiers in Microbiology, 13, (2022): 831828, https://doi.org/10.3389/fmicb.2022.831828.Hydrocarbons are degraded by specialized types of bacteria, archaea, and fungi. Their occurrence in marine hydrocarbon seeps and sediments prompted a study of their role and their potential interactions, using the hydrocarbon-rich hydrothermal sediments of Guaymas Basin in the Gulf of California as a model system. This sedimented vent site is characterized by localized hydrothermal circulation that introduces seawater sulfate into methane- and hydrocarbon-rich sediments, and thus selects for diverse hydrocarbon-degrading communities of which methane, alkane- and aromatics-oxidizing sulfate-reducing bacteria and archaea have been especially well-studied. Current molecular and cultivation surveys are detecting diverse fungi in Guaymas Basin hydrothermal sediments, and draw attention to possible fungal-bacterial interactions. In this Hypothesis and Theory article, we report on background, recent results and outcomes, and underlying hypotheses that guide current experiments on this topic in the Edgcomb and Teske labs in 2021, and that we will revisit during our ongoing investigations of bacterial, archaeal, and fungal communities in the deep sedimentary subsurface of Guaymas Basin.This project was supported by collaborative NSF Biological Oceanography grants OCE-1829903 and OCE-1829680 “Hydrothermal fungi in the Guaymas Basin Hydrocarbon Ecosystem” to VE and AT, and collaborative NSF Biological Oceanography grants OCE-2046799 and OCE-2048489 “IODP-enabled Insights into Fungi and Their Metabolic Interactions with Other Microorganisms in Deep Subsurface Hydrothermal Sediments” to VE and AT. PM was supported by OCE-2046799 and OCE-1829903. Sampling in Guaymas Basin was supported by collaborative NSF Biological Oceanography grant 1357238 “Collaborative Research: Microbial carbon cycling and its interaction with sulfur and nitrogen transformations in Guaymas Basin hydrothermal sediments” to AT