Figure 4. Structure of the T. kodakaraensis archaellum. (A) A sub-tomogram average of the archaellum reveals structural features, including four layers of density in the cytoplasm (L1-L3, cone). CM, cytoplasmic membrane. The speculated identity of densities in the archaellum is proposed: archaellum fiber = FlaA/B flagellins; integral membrane density = FlaJ; L1 = FlaI; L2/L3/cone = FlaH/FlaC/D/E.Scale bar 10 nm (applies to A, B). 