BvgAS signal transduction motif.
The signal transduction motif is composed of the phosphotransfer and autoregulation modules. The temperature acts as inducer of the autophosphorylation of the dimer of the sensor kinase protein BvgS (blue). Similarly, dimerized BvgA represents for response regulator in red. P in black sphere stands for phosphate group. Note that, sensor kinase acts both as source and sink for the phosphate group.