Cover photograph (Copyright © 2007, American Society for Microbiology. All Rights Reserved.): Merged confocal scanning laser microscopy images (red and green) of methicillin-resistant Staphylococcus aureus biofilms stained with SYTO9 to reveal all cells within the biofilm (shown in green). Biofilms were probed with rabbit IgG against the biofilm-upregulated antigens of a conserved hypothetical protein, followed by probing with secondary anti-rabbit F(ab′)2 (red). (See related article on page 6612.)