[Spirochetes: coiling direction].

Abstract

On electron micrographs of spirochetes, the axial fibers are alternatively visible and hidden, i.e. above then under the cytoplasmic cylinder. From this observation the sense of coiling can be inferred. Leptospires are right-handed structures. So are other spirochetes, but it is less conspicuous. The opposite, however, appears on most published photographs and on schematic drawings. The explanation would be that the preparation introduced into the electron microscope was not facing the photographic plate, but turned to the electron beam. Also the picture must not be turned over, neither in the photographic laboratory nor when used as a slide.