Activity and diversity of sulfate- and methane-based pathways of anaerobic chitin and N-acetylglucosamine degradation in marine sediments.

Complex organic carbon inputs, like chitin, enhance microbial diversity and foster diverse microbial networks in marine sediments, including methanogenic lineages.

• Why it matters: Understanding how complex and recalcitrant organic matter influences sediment microbial communities is crucial for revealing their roles in oceanic carbon cycling and ecosystem stability.
• What they did: Multi-month microcosm experiments with sediments from a deep-sea whalefall site were conducted, adding either chitin or N-acetylglucosamine, and analyzed through geochemistry, 16S rRNA gene sequencing, and metagenomics.
• The result: Complex carbon inputs promoted unique microbial assemblages and interactions, including rare methanogens, indicating that organic complexity stimulates diverse, functionally connected microbial communities in anoxic sediments.