Fig. 1: Involvement of c-di-AMP in cyanobacterial natural competence via ComFB signaling protein.
From: The second messenger c-di-AMP controls natural competence via ComFB signaling protein
a Transformation efficiency of WT, ∆dacA, ∆dacA::petE-dacA, WT::petE-dacA and ∆sbtB strains (see also Supplementary Fig. S1). b Immunodetection of PilA1 in the exoproteome of WT and ∆dacA. c Pulldown experiment using immobilized c-di-AMP and extracts of Synechocystis cells grown under day-night cycles, showing the enriched proteins in the day phase. Potential new c-di-AMP receptors are highlighted in orange. d Phylogenetic tree showing that ComFB proteins are widespread among different bacterial phyla (detailed tree Supplementary Fig. S4). e Dissociation constant (KD) of c-di-AMP binding to ComFB and enthalpy (ΔH) are obtained from sigmoidal fitting curve of all ITC experiments with different monomeric ComFB concentrations. f DRaCALA assay showing the binding of [32P]c-di-AMP to purified ComFB in a concentration dependent manner as indicated. The upper panel shows a representative of one replicate from four technical replicates. The lower panel shows the calculated mean ± SD of the quantification of the bound fraction of [32P]c-di-AMP to ComFB from the four replicates and the best fitting curve with the obtained KD value. g DRaCALA competition binding assay showing the competition of [32P]c-di-AMP with different nucleotides to bind ComFB. NC refers to no competitor. SbtB and cell extract of E. coli harboring an empty plasmid were used as positive and negative control, respectively. h Transformation efficiency of WT, ∆comFB, and ΔcomFB::petE-comFB strains (see also Supplementary Fig. S1).
