Fig. 3: ComK2 interacts with SA2107.

a Yeast two-hybrid experiment revealing a physical interaction between ComK2 and SA2107. A fusion between ComK2 and the GAL4 binding domain (BD) was used as a bait to screen a S. aureus genomic library constructed in a GAL4 activation domain (AD) prey vector. The full length SA2107 protein was identified in this screen. The interaction is revealed on a complete, synthetic and selective medium lacking leucine, uracile and adenine (to select for expression of the ADE2 interaction reporter). Negative controls harboring empty vectors (empty pBGDU, strain 121 and empty pGAD, strain 131). b Predicted structure of the ComK2-SA2107 complex using AlphaFold2. ComK2 is displayed in green and SA2107 in cyan. The amino acids at the interaction interface are highlighted in the “wire format” in yellow for SA2107 and in red for ComK2 (visualization of residues as sticks, see Supp. Fig. 2 for details). c Measured Hydrodynamic radius of SA2107 in complex with ComK2 using the Flow Induced Dispersion Analysis (FIDA²⁶) method. A constant concentration of labelled SA2107 (20 nM) is exposed to increasing concentrations of ComK2 (15 nM-2 μM). SA2107 hydrodynamic radius is calculated based on three independent experiments (mean and SD). For each data point, individual hydrodynamic radius values are presented as blue circles. d Comparison of the calculated and estimated hydrodynamic radius of SA2107 alone and in the presence of ComK2 or ComK1. The dissociation constant (Kd) of the ComK2-SA2107 interaction is shown.