Cover photograph (Copyright © 2005, American Society for Microbiology. All Rights Reserved.): Gliding motility of Mycoplasma pneumoniae. The cells form a membrane protrusion, called an “attachment organelle,” at a cell pole and glide in its direction. Selected frames from 10s video were differently colored from purple to red and integrated into one image, using an algorithm developed by Yuichi Hiratsuka (AIST, Tsukuba, Japan). The traces in the image show gliding speed, direction of gliding, and time relations with other traces. The mycoplasma cells always glide in the direction of the attachment organelle, but the direction does not always correspond to the cell axis. (See related article on page 1875.)