Ligand sensing enhances bacterial flagellar motor output via stator recruitment

It is well known that flagellated bacteria, such as Escherichia coli , sense chemicals in their environment by a chemoreceptor and relay the signals via well-characterized signaling pathway to flagellar motor. widely accepted change rotation bias of motor without influencing speed. Here, we present results contrary show bacteria also capable modulating speed on merely sensing ligand. Step changes concentration non-metabolizable ligand cause temporary recruitment stator units leading momentary increase speeds. For metabolizable ligand, combined effect metabolism leads higher speeds for longer durations. Experiments performed with mutant strains delineate role modulation how along can significantly enhance response its environment.