Convergent Microbial Community Formation in Replicate Anaerobic Reactors Inoculated from Different Sources and...

Area of Science:

• Astrobiology
• Microbial Ecology
• Environmental Engineering

Background:

• Efficient nutrient recycling is crucial for long-duration manned space missions.
• Microbial systems offer a low-energy solution for nutrient recovery from waste.
• Reproducibility in microbial community formation is essential for life support system reliability.

Purpose of the Study:

• To evaluate the reproducibility of microbial community development in fixed-film anaerobic reactors.
• To compare microbial community formation and reactor performance using different inocula sources.
• To determine the feasibility of using preserved microbial communities for life support systems.

Main Methods:

• Inoculation of replicate anaerobic reactors from two distinct methanogenic sources.
• Operation of reactors under identical environmental conditions.
• Assessment of reactor performance and microbial community structure via 16S rDNA amplicon sequencing.

Main Results:

• Reactor microbial communities were dominated by similar phylogenetic groups.
• Distinct differences in microbial community membership were observed between reactors from different inocula.
• Overlapping reactor performance indicated convergence in organic matter mineralization.

Conclusions:

• Optimized microbial communities can be preserved and utilized to establish new or restart failed anaerobic reactors.
• This approach promises predictable reactor performance for space-based life support systems.
• Microbial community seeding offers a viable strategy for robust nutrient recycling in extraterrestrial habitats.