Extended Data Fig. 2: Metabolic pathways related to cobalamin biosynthesis and transcript expression patterns of Colwellia and Roseovarius grown in co-culture.

Differential gene expression between the control, represented by the mono-cultures (Roseovarius & Colwellia) with B₁₂ added, and the co-culture, without B₁₂ addition, was quantified with the DESeq2 package as implemented in R v4.0.5 (R-Core-Team, 2022). In each treatment n = 3 biological independent samples were used. Coloring of genes refers to their LOG-2FC regulation, defined as downregulated (light red to red), upregulated (light green to dark green) and similarly regulated (orange). Genes that are significantly regulated (LOG2-FC larger than 2 and smaller than −2 with an BH adj. p-value < 0.05) are marked with an asterisk. When an illustration represents more than one gene (all genes > (-) 2 LOG-2FC and adj. p-value < 0.05), the asterisk is placed in brackets. Genes that were not identified in the genome (grey). Since the bluB gene in Roseovarius is missing a large section of the sequence, we have indicated this by outlining the gene in gray. Corresponding gene expression significances (adjusted p-value) and further details on genes are presented in Supplementary Data 2. Our documented microbial interactions including the coincidence of prophage induction, host cell lysis and release of B₁₂, whose causative relationships still need to be proven, are illustrated and explained by the dashed arrows and the explanations 1–6 in the legend.