23 June 2006
Vol 312, Issue 5781

About The Cover

Cover image expansion

COVER The pressure-sensing mechanism of bacteriophage P22 that signals when the phage head is full, viewed from the interior. The portal complex (red) is hypothesized to change conformation when the virus is full of DNA (green), which signals the packaging motors to stop. Such a sensor may serve as a drug target in human viruses. See page 1791. Image: G. Johnson and G. Lander