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Proc Natl Acad Sci U S A

Title:		Daily bursts of biogenic cyanogen bromide (BrCN) control biofilm formation around a marine benthic diatom
Author(s):		Vanelslander B; Paul C; Grueneberg J; Prince EK; Gillard J; Sabbe K; Pohnert G; Vyverman W;
Address:		"Laboratory of Protistology and Aquatic Ecology, Department of Biology, Ghent University, 9000 Ghent, Belgium"
Journal Title:		Proc Natl Acad Sci U S A
Year:		2012
Volume:		20120130
Issue:		7
Page Number:		2412 - 2417
DOI:		10.1073/pnas.1108062109
ISSN/ISBN:		1091-6490 (Electronic) 0027-8424 (Print) 0027-8424 (Linking)
Abstract:		"The spatial organization of biofilms is strongly regulated by chemical cues released by settling organisms. However, the exact nature of these interactions and the repertoire of chemical cues and signals that micro-organisms produce and exude in response to the presence of competitors remain largely unexplored. Biofilms dominated by microalgae often show remarkable, yet unexplained fine-scale patchy variation in species composition. Because this occurs even in absence of abiotic heterogeneity, antagonistic interactions might play a key role. Here we show that a marine benthic diatom produces chemical cues that cause chloroplast bleaching, a reduced photosynthetic efficiency, growth inhibition and massive cell death in naturally co-occurring competing microalgae. Using headspace solid phase microextraction (HS-SPME)-GC-MS, we demonstrate that this diatom exudes a diverse mixture of volatile iodinated and brominated metabolites including the natural product cyanogen bromide (BrCN), which exhibits pronounced allelopathic activity. Toxin production is light-dependent with a short BrCN burst after sunrise. BrCN acts as a short-term signal, leading to daily 'cleaning' events around the algae. We show that allelopathic effects are H(2)O(2) dependent and link BrCN production to haloperoxidase activity. This strategy is a highly effective means of biofilm control and may provide an explanation for the poorly understood role of volatile halocarbons from marine algae, which contribute significantly to the atmospheric halocarbon budget"
Keywords:		*Biofilms Cyanogen Bromide/*metabolism Diatoms/*metabolism Gas Chromatography-Mass Spectrometry Pheromones/*metabolism Solid Phase Microextraction;
Notes:		"MedlineVanelslander, Bart Paul, Carsten Grueneberg, Jan Prince, Emily K Gillard, Jeroen Sabbe, Koen Pohnert, Georg Vyverman, Wim eng Research Support, Non-U.S. Gov't 2012/02/07 Proc Natl Acad Sci U S A. 2012 Feb 14; 109(7):2412-7. doi: 10.1073/pnas.1108062109. Epub 2012 Jan 30"