New insights into anaerobic co-digestion of sewage sludge and food waste inferred from metagenome-assembled genomes

ORELLANA, E.; DAVIS-SALA, C.; GUERRERO, L.D.; ERIJMAN, L

Virtual

Jornada; Jornadas Latinoamericanas en Digestión Anaerobia 2020; 2020

International Water Association (IWA)

This work aims at understanding the structural and functional dynamics of the digestion microbiome upon changes in substrate composition and concentration. Genome-centric metagenomics was used to investigate the functional basis of shifts in microbial communities treating sewage sludge and food waste in laboratory-scale digesters (5 L). The analysis of metagenome assembled genomes from 49 samples revealed that bacteria, whose abundance correlates with the concentration of food waste in the feed, are hydrolytic bacteria containing enzymes belonging to the glycosyl hydrolase family. A diverse group of hydrogenotrophic methanogens seem to provide thermodynamically favorable conditions for primary fermentative bacteria to generate acetate, which is converted into methane by a dominant archaea of the genus Methanothrix.