Architecture of the outer regions of the basal body.

(A) Composite map of the highest-resolution maps obtained for the outer regions of the needle complex (left panel), including the focused IM ring map with C24 symmetry, the connector map from the focused IM-connector reconstruction with C8 symmetry and the OM ring map from C1 reconstruction. The cyclic symmetry of the three regions is indicated on the left. (B) Atomic models of the corresponding needle complex proteins built using maps depicted in (A): MxiG (blue), MxiJ (orange) and MxiD (green).