title: A Novel Epiphytic Chlorophyll d-containing Cyanobacterium Isolated from a Mangrove-associated Red Alga.
abstract: A new habitat and a new chlorophyll (Chl) d-containing cyanobacterium belonging to the genus Acaryochloris are reported in this study. Hyperspectral microscopy showed the presence of Chl d-containing microorganisms in epiphytic biofilms on a red alga (Gelidium caulacantheum) colonizing the pneumato-phores of a temperate mangrove (Avicennia marina). The presence of Chl d was further proven by high performance liquid chromatography (HPLC)-based pigment analysis and by confocal imaging of cultured cells. Enrichment of mangrove biofilm samples under near-infrared radiation (NIR) yielded the new Acaryochloris sp. MPGRS1, which was closely related in terms of 16S rRNA gene sequence to an isolate from the hypertrophic Salton Sea, USA. The new isolate used Chl d as its major photopigment; Chl d and Chl a contents were ~98% and 1%-2% of total cellular chlorophyll, respectively. These findings expand the variety of ecological niches known to harbor Chl d-containing cyanobacteria and support our working hypothesis that such oxyphototrophs may be ubiquitous in habitats depleted of visible light, but with sufficient NIR exposure.
authors.affiliation: School of Biological Sciences (A08), University of Sydney, Sydney, NSW, 2006, Australia.
authors.forename: Anthony W D
authors.initials: AW
authors.lastname: Larkum
authors.affiliation: School of Biological Sciences (A08), University of Sydney, Sydney, NSW, 2006, Australia.
authors.forename: Min
authors.initials: M
authors.lastname: Chen
authors.affiliation: School of Biological Sciences (A08), University of Sydney, Sydney, NSW, 2006, Australia.
authors.forename: Yaqiong
authors.initials: Y
authors.lastname: Li
authors.affiliation: School of Biological Sciences (A08), University of Sydney, Sydney, NSW, 2006, Australia.
authors.forename: Martin
authors.initials: M
authors.lastname: Schliep
authors.affiliation: Marine Biological Section, Department of Biology, University of Copenhagen, Strandpromenaden 5, Helsingør, DK-3000, Denmark.
authors.forename: Erik
authors.initials: E
authors.lastname: Trampe
authors.affiliation: School of Botany, University of Melbourne, Parkville, Victoria, 3024, Australia.
authors.forename: John
authors.initials: J
authors.lastname: West
authors.affiliation: Confocal Bio-Imaging Facility, School of Science and Health, University of Western Sydney, Richmond, NSW, 2753, Australia.
authors.forename: Anya
authors.initials: A
authors.lastname: Salih
authors.affiliation: Marine Biological Section, Department of Biology, University of Copenhagen, Strandpromenaden 5, Helsingør, DK-3000, Denmark.|Plant Functional Biology and Climate Change Cluster, University of Technology Sydney, Ultimo, NSW, 2007, Australia.
authors.forename: Michael
authors.initials: M
authors.lastname: Kühl
keywords: Cyanobacteria; chlorophyll d; epiphyte; mangrove; photosynthesis