Seminar of the Department of Microbiology
Diversity and evolution of complex organic matter degradation capabilities of marine Verrucomicrobiota
Luis H. Orellana, PhD - Project leader - Max-Planck-Institut für Marine Mikrobiologie
01.02.2024, 11:00 - Hybrid
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- or in presence: HSB4 (Technikerstraße 13b, EG)
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Abstract
The members of the Verrucomicrobiota phylum are bacteria commonly found in soil, marine, and gut environments. Recent studies suggest that many Verrucomicrobiota members specialize in breaking down a variety of polysaccharides, especially hard-to-degrade sugars. In marine environments, these algae-derived sulfated polysaccharides contain methyl pentoses and are challenging to degrade for most bacteria, implicating them as a potential carbon sink. Here, we investigated samples from different-sized fractions obtained during a North Sea spring bloom using visualization and multi-omic approaches. Verrucomicrobial populations rely on hard-wired adaptations specific to hard-to-degrade organic matter, such as fucosidases, sulfatases, and bacterial microcompartments. These specialized pathways were detected in metaproteomes belonging to the Akkermansia and DSM-45221 families. Akkermansia recovered genomes were more prevalent in metagenomic samples from higher-sized fractions, unlike members of the DSM-45221 family, indicating an apparent niche differentiation. Nonetheless, the visualization of Akkermansia cells attached to particles indicated a likely alternating free-living and particle-associated lifestyle, unlike the solely free-living lifestyle of DSM-45221. Thus, our results suggest that specialized Verrucomicrobiota populations occupying different niches could determine the fate of complex polysaccharides consumed during algal blooms and impact marine carbon sequestration.