Modeling the mutualistic interactions between tubeworms and microbial consortia

Area of Science:

• Marine biology
• Geochemistry
• Microbial ecology

Background:

• Deep-sea tubeworms, Lamellibrachia luymesi, form long-lasting aggregations at hydrocarbon seeps.
• These ecosystems are characterized by unique geochemical conditions and microbial communities.

Purpose of the Study:

• To model how tubeworm aggregations persist for centuries.
• To investigate the role of tubeworm-released sulfate in supporting seep ecosystems.

Main Methods:

• Development of a diagenetic model simulating nutrient cycling at hydrocarbon seeps.
• Incorporation of sulfate release by L. luymesi symbionts into the model.

Main Results:

• Tubeworm-derived sulfate augments sulfate supply to sediments, sustaining microbial processes.
• Sulfate fuels sulfate reduction coupled with anaerobic methane oxidation and hydrocarbon degradation.
• Model indicates sufficient sulfate release to support tubeworm aggregations for hundreds of years.

Conclusions:

• Complex interspecific relationships, including symbiosis, are crucial for deep-sea ecosystem stability.
• Lamellibrachia luymesi plays a key role in sustaining its own habitat through symbiotic microbial processes.
• This highlights the intricate interactions across all three domains of life in extreme environments.