Biofilms 2012: new discoveries and significant wrinkles in a dynamic field

Abstract

The ASM 6th Conference on Biofilms was held in Miami, Florida, 29 September to 4 October, 2012. The conference provided an opportunity for the exchange of new findings and ideas with regard to biofilm research. A wide range of findings, spanning applied biology, evolution, ecology, physiology, and molecular biology, were presented at the conference. This review summarizes the presentations with regard to emerging biofilm-related themes.

Fig 1

Wrinkled and otherwise complex colony morphologies. Left to right: B. subtilis colony (reprinted from Cold Spring Harbor Perspectives in Biology [73] with permission of the publisher), Agrobacterium tumefaciens on agar plus Congo red (image courtesy of Jing Xu and C. Fuqua), Vibrio fischeri colony (image courtesy of V. Ray and K. Visick), and Pseudomonas fluorescens wrinkly spreader colony (image courtesy of Andrew Spier).

Fig 2

Cell death predicts wrinkle formation in B. subtilis colonies. (Top) Area of induced cell death; (bottom) wrinkle formation. Reprinted from Proceedings of the National Academy of Sciences of the United States of America (1) with permission of the publisher.

Fig 3

Temporal progression of matrix components during the early stages of V. cholerae biofilm formation. (Top) Phase-contrast microscopy; (bottom) same images merged with fluorescence channels for matrix components. From V. Berk et al., Science 337:236–239, 2012 (22). Reprinted with permission from AAAS.

Fig 4

(Top) Fluorescence in situ hybridization (FISH) of a human heart valve section, showing streptococci in a culture-negative case of infective endocarditis. The overview (left) shows a structured biofilm (blue) within the heart valve tissue (green background fluorescence). Nucleic acids were nonspecifically stained with DAPI (4′,6-diamidino-2-phenylindole dihydrochloride) (blue). (Inset, right) Layers of Streptococcus spp. (hybridized with a genus-specific FISH probe, in orange) show high ribosomal content within this monospecies biofilm. (Bottom) FISH of a subgingival biofilm from a periodontitis patient. The overview (left) shows the complex multispecies biofilm stained with a genus-specific probe for streptococci (orange) combined with EUB338 (green), which detects most bacteria, and the nucleic acid stain DAPI (blue). At higher resolution (inset, right), the streptococci appear to grow along the orientation of the rods. Images courtesy of Annette Moter.