Data from: Auxotrophy and intra-population complementary in the 'interactome' of a cultivated freshwater model community

Microorganisms are usually studied either in highly complex natural
communities or in isolation as monoclonal model populations that we manage
to grow in the laboratory. Here, we uncover the biology of some of the
most common and yet-uncultured bacteria in freshwater environments using a
mixed culture from Lake Grosse Fuchskuhle. From a single shotgun
metagenome of a freshwater mixed culture of low complexity, we recovered
four high-quality metagenome-assembled genomes (MAGs) for metabolic
reconstruction. This analysis revealed the metabolic interconnectedness
and niche partitioning of these naturally dominant bacteria. In
particular, vitamin- and amino acid biosynthetic pathways were distributed
unequally with a member of Crenarchaeota most likely being the sole
producer of vitamin B12 in the mixed culture. Using coverage-based
partitioning of the genes recovered from a single MAG intrapopulation
metabolic complementarity was revealed pointing to ‘social’ interactions
for the common good of populations dominating freshwater plankton. As
such, our MAGs highlight the power of mixed cultures to extract naturally
occurring ‘interactomes’ and to overcome our inability to isolate and grow
the microbes dominating in nature.