Long-term cultivation and meta-omics reveal methylotrophic methanogenesis in hydrocarbon-impacted habitats

TY - JOUR

T1 - Long-term cultivation and meta-omics reveal methylotrophic methanogenesis in hydrocarbon-impacted habitats

AU - Liu, Yi-Fan

AU - Chen, Jing

AU - Liu, Zhong-Lin

AU - Hou, Zhao-Wei

AU - Liang, Bo

AU - Wang, Li-Ying

AU - Zhou, Lei

AU - Shou, Li-Bin

AU - Lin, Dan-Dan

AU - Yang, Shi-Zhong

AU - Liu, Jin-Feng

AU - Wu, Xiao-Lin

AU - Gu, Ji-Dong

AU - Mu, Bo-Zhong

PY - 2022/1/10

Y1 - 2022/1/10

N2 - The microbial conversion of alkanes to methane in hydrocarbon-contaminated environments is an intrinsic bioremediation strategy under anoxic conditions. However, the mechanism of microbial methanogenic alkane degradation is currently unclear. Under ten-years of continuous efforts, we obtained a methanogenic n-alkane-degrading (C15–C20) enrichment culture that exhibited sustained improvements in the kinetic properties of methane production. The integrated metagenomic and metatranscriptomic analyses revealed that n-alkanes were mainly attacked by members of Desulfosarcinaceae, Firmicutes, and Synergistetes using the fumarate addition strategy, and were then further degraded in a common effort by Tepidiphilus members. Meanwhile, the abundant members of Anaerolineaceae were mainly responsible for cell debris recycling. However, according to the metatranscriptomic analyses, methane was predicted to be produced mainly via H2-dependent methylotrophic methanogenesis, primarily from necromass-derived trimethylamine mediated by Methanomethyliaceae within the candidate phylum Verstraetearchaeota. These findings reveal that H2-dependent methylotrophic methanogens, as well as methylotrophic methanogens, may play important ecological roles in the carbon cycle of hydrocarbon enriched subsurface ecosystems.

AB - The microbial conversion of alkanes to methane in hydrocarbon-contaminated environments is an intrinsic bioremediation strategy under anoxic conditions. However, the mechanism of microbial methanogenic alkane degradation is currently unclear. Under ten-years of continuous efforts, we obtained a methanogenic n-alkane-degrading (C15–C20) enrichment culture that exhibited sustained improvements in the kinetic properties of methane production. The integrated metagenomic and metatranscriptomic analyses revealed that n-alkanes were mainly attacked by members of Desulfosarcinaceae, Firmicutes, and Synergistetes using the fumarate addition strategy, and were then further degraded in a common effort by Tepidiphilus members. Meanwhile, the abundant members of Anaerolineaceae were mainly responsible for cell debris recycling. However, according to the metatranscriptomic analyses, methane was predicted to be produced mainly via H2-dependent methylotrophic methanogenesis, primarily from necromass-derived trimethylamine mediated by Methanomethyliaceae within the candidate phylum Verstraetearchaeota. These findings reveal that H2-dependent methylotrophic methanogens, as well as methylotrophic methanogens, may play important ecological roles in the carbon cycle of hydrocarbon enriched subsurface ecosystems.

KW - Methanogenic hydrocarbon degradation

KW - Oily sludge

KW - Bioremediation

KW - Alkanes

U2 - 10.1016/j.eng.2021.08.027

DO - 10.1016/j.eng.2021.08.027

M3 - 文章

SN - 2095-8099

JO - Engineering

JF - Engineering

ER -