Contents

21 May 1999
Vol 284, Issue 5418

About The Cover

Cover image expansion

COVER Initial stage of Pseudomonas aeruginosa biofilm formation on an explant of human lung tissue. Green shows P. aeruginosa, tagged with a fluorescent protein, on the epithelial surface (red-light microscopic image). The bacteria (2 to 3 µm long) form microcolonies in the intercellular junctions around injured cells. A special section on microbes, immunity, and disease begins on p. 1301 [Image: P. Singh, M. Parsek, T. Moninger, E. P. Greenberg, University of Iowa] .