Number of steps of flagellar motor per revolution

Value 26 steps/revolution
Organism Bacteria Escherichia coli
Reference Sowa Y, Rowe AD, Leake MC, Yakushi T, Homma M, Ishijima A, Berry RM. Direct observation of steps in rotation of the bacterial flagellar motor. Nature. 2005 Oct 6 437(7060):916-9. Abstract & p.917 right column top, 2nd and bottom paragraphs & p.918 left column top paragraphPubMed ID16208378
Method "[Researchers] detected rotation by back-focal-plane (BFP) interferometry of 500-nm diameter polystyrene beads attached to spontaneously sticky flagellar filaments of E. coli, as described previously [ref 16], or by high-speed video recording of 200-nm fluorescent beads attached in the same way (Fig. 1b, c, inset)."
Comments "[Researchers] observe 26 steps per revolution, which is consistent with the periodicity of the ring of FliG protein, the proposed site of torque generation on the rotor [refs 7,8]...The peak at 26 per revolution in the spectrum corresponds to steps of 13.8° and indicates that successive revolutions show the same stopping angles."
Entered by Uri M
ID 110614