Genome-Centric Metatranscriptomics Reveals Multiple Co-occurring Routes for Hydrocarbon Degradation in Chronically...

Area of Science:

• Environmental microbiology
• Marine ecology
• Biogeochemistry

Background:

• Long-term hydrocarbon pollution poses a significant threat to marine ecosystems.
• Understanding microbial adaptation and activity under chronic pollution is crucial for ecosystem health.

Purpose of the Study:

• To investigate microbial responses to over 80 years of chronic hydrocarbon pollution in marine environments.
• To analyze the activity of hydrocarbon degradation pathways at the population level using advanced omics techniques.

Main Methods:

• Genome-centric metagenomic and metatranscriptomic analyses were performed on microbial mat samples.
• Transcriptomic activity of alkane and aromatic hydrocarbon degradation pathways was assessed.

Main Results:

• Both aerobic and anaerobic hydrocarbon degradation pathways were actively expressed by diverse microbial lineages.
• Microbial populations with various metabolisms, including photo-heterotrophic and sulfur-based, contributed to degradation.
• Hydrocarbon concentration and composition strongly structured intrafamily diversity and transcriptomic activity within bacterial families.

Conclusions:

• Shallow marine microbial mats exhibit co-occurring aerobic and anaerobic hydrocarbon degradation.
• Widely distributed marine bacteria play a key role in long-term aerobic alkane degradation, with their activity modulated by pollution specifics.