Cover photograph (Copyright © 2005, American Society for Microbiology. All Rights Reserved.): Adherence of Escherichia coli O157:H7 to HEp-2 cells. The bacteria were stained with a monoclonal antibody against the O157 antigen (green), and host cell actin was stained with the fungal toxin phalloidin conjugated to Alexa 594 (red). These bacteria are capable of causing “pedestals,” an intimate form of adherence whereby host cell actin is bundled underneath the bacteria and pushes the bacteria up above the host cell surface. This effect is indicated by the bright red spots (bundled actin) next to bacteria (green). Regions of colocalization of actin and bacteria are indicated by yellow. (See related article in the March 2005 issue: vol. 73, page 1295.)