Article

A niche for cyanobacteria containing chlorophyll d. Nature 433:820

Marine Biological Laboratory, Institute of Biology, University of Copenhagen, 3000 Helsingør, Denmark.
Nature (Impact Factor: 42.35). 03/2005; 433(7028):820. DOI: 10.1038/433820a
Source: PubMed

ABSTRACT The cyanobacterium known as Acaryochloris marina is a unique phototroph that uses chlorophyll d as its principal light-harvesting pigment instead of chlorophyll a, the form commonly found in plants, algae and other cyanobacteria; this means that it depends on far-red light for photosynthesis. Here we demonstrate photosynthetic activity in Acaryochloris-like phototrophs that live underneath minute coral-reef invertebrates (didemnid ascidians) in a shaded niche enriched in near-infrared light. This discovery clarifies how these cyanobacteria are able to thrive as free-living organisms in their natural habitat.

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Available from: Michael Kühl, Aug 28, 2015
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    • "A radical redesign of the photosynthetic apparatus for both bioenergy and food production application may be realized utilizing techniques in synthetic biology to engineer the photosystem in energy storage and RuBisCo in carbon fixation (Blankenship et al. 2011). Among prokaryotic photosynthetic cyanobacteria, A. marina is a unique phototroph that uses Chl d as its principle light-harvesting pigment instead of Chl a (Akiyama et al. 2001; Kuhl et al. 2005). The minor difference in the structure of Chl d, C3-formyl group on ring 1, compared with the vinyl group of Chl a, results in Chl d having an absorption peak more red-shift than Chl a in acetone which is shifted about 30 nm compared to Chl a (Hu et al. 1998; Chen et al. 2002). "
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    • "Acaryochloris, another atypical cyanobacterium frequently found in association with Prochloron contains yet another major pigment, Chl d, a unique chromophore that absorbs near-infrared light (Miyashita et al. 1997). It is worth noting that Acaryochloris was initially thought to be an endosymbiont of ascidians (Miyashita et al. 2003), but a more recent analysis showed that is in fact a free-living epiphyte of those invertebrates (Kuhl et al. 2005) and it has been retrieved subsequently in a variety of benthic environments, including from underneath the crust of coralline algae living in coral reefs (Behrendt et al. 2010; Mohr et al. 2010a). While Prochloron has never been cultivated, several Acaryochloris has been successfully brought into culture and three strains have been sequenced to date (Swingley et al. 2008; Mohr et al. 2010a; Pfreundt et al. 2012). "
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