title: Genome Sequence of Rhodoferax antarcticus ANT.BRT; A Psychrophilic Purple Nonsulfur Bacterium from an Antarctic Microbial Mat.
abstract: Rhodoferax antarcticusis an Antarctic purple nonsulfur bacterium and the only characterized anoxygenic phototroph that grows best below 20 °C. We present here a high-quality draft genome ofRfx. antarcticusstrain ANT.BRT, isolated from an Antarctic microbial mat. The circular chromosome (3.8 Mbp) ofRfx. antarcticushas a 59.1% guanine + cytosine (GC) content and contains 4036 open reading frames. In addition, the bacterium contains a sizable plasmid (198.6 kbp, 48.4% GC with 226 open reading frames) that comprises about 5% of the total genetic content. Surprisingly, genes encoding light-harvesting complexes 1 and 3 (LH1 and LH3), but not light-harvesting complex 2 (LH2), were identified in the photosynthesis gene cluster of theRfx. antarcticusgenome, a feature that is unique among purple phototrophs. Consistent with physiological studies that showed a strong capacity for nitrogen fixation inRfx. antarcticus, a nitrogen fixation gene cluster encoding a molybdenum-type nitrogenase was present, but no alternative nitrogenases were identified despite the cold-active phenotype of this phototroph. Genes encoding two forms of ribulose 1,5-bisphosphate carboxylase/oxygenase were present in theRfx. antarcticusgenome, a feature that likely provides autotrophic flexibility under varying environmental conditions. Lastly, genes for assembly of both type IV pili and flagella are present, with the latter showing an unusual degree of clustering. This report represents the first genomic analysis of a psychrophilic anoxygenic phototroph and provides a glimpse of the genetic basis for maintaining a phototrophic lifestyle in a permanently cold, yet highly variable, environment.
authors.affiliation: Division of Natural Sciences, Indiana Wesleyan University, Marion, IN 46953, USA. jenn.baker@myemail.indwes.edu.
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Baker
authors.affiliation: Division of Natural Sciences, Indiana Wesleyan University, Marion, IN 46953, USA. carliriester@gmail.com.
authors.forename: Carli J
authors.initials: CJ
authors.lastname: Riester
authors.affiliation: Division of Natural Sciences, Indiana Wesleyan University, Marion, IN 46953, USA. blair.skinner@myemail.indwes.edu.
authors.forename: Blair M
authors.initials: BM
authors.lastname: Skinner
authors.affiliation: Division of Natural Sciences, Indiana Wesleyan University, Marion, IN 46953, USA. austinwayne.newell@gmail.com.
authors.forename: Austin W
authors.initials: AW
authors.lastname: Newell
authors.affiliation: Department of Biological Sciences, Northern Illinois University, DeKalb, IL 60115, USA. wswingley@niu.edu.
authors.forename: Wesley D
authors.initials: WD
authors.lastname: Swingley
authors.affiliation: Department of Microbiology, Southern Illinois University, Carbondale, IL 62901, USA. madigan@siu.edu.
authors.forename: Michael T
authors.initials: MT
authors.lastname: Madigan
authors.affiliation: Department of Microbiology, Southern Illinois University, Carbondale, IL 62901, USA. debjung@siu.edu.
authors.forename: Deborah O
authors.initials: DO
authors.lastname: Jung
authors.affiliation: Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA. marie.asao@gmail.com.
authors.forename: Marie
authors.initials: M
authors.lastname: Asao
authors.affiliation: School of Life and Environmental Sciences, The University of Sydney, New South Wales 2006, Australia. min.chen@sydney.edu.au.
authors.forename: Min
authors.initials: M
authors.lastname: Chen
authors.affiliation: School of Life and Environmental Sciences, The University of Sydney, New South Wales 2006, Australia. patftct@gmail.com.
authors.forename: Patrick C
authors.initials: PC
authors.lastname: Loughlin
authors.affiliation: School of Life and Environmental Sciences, The University of Sydney, New South Wales 2006, Australia. dylanwind@gmail.com.
authors.forename: Hao
authors.initials: H
authors.lastname: Pan
authors.affiliation: School of Life and Environmental Sciences, The University of Sydney, New South Wales 2006, Australia. ylin2801@uni.sydney.edu.au.
authors.forename: Yuankui
authors.initials: Y
authors.lastname: Lin
authors.affiliation: School of Life and Environmental Sciences, The University of Sydney, New South Wales 2006, Australia. Yaqiong.li@sydney.edu.au.
authors.forename: Yaqiong
authors.initials: Y
authors.lastname: Li
authors.affiliation: Departments of Biology and Chemistry, Washington University in Saint Louis, St. Louis, MO 63130, USA. jacobsshaw@gmail.com.
authors.forename: Jacob
authors.initials: J
authors.lastname: Shaw
authors.affiliation: Departments of Biology and Chemistry, Washington University in Saint Louis, St. Louis, MO 63130, USA. mcpty5@gmail.com.
authors.forename: Mindy
authors.initials: M
authors.lastname: Prado
authors.affiliation: Departments of Biology and Chemistry, Washington University in Saint Louis, St. Louis, MO 63130, USA. shermanc@wustl.edu.
authors.forename: Chris
authors.initials: C
authors.lastname: Sherman
authors.affiliation: Departments of Biology and Chemistry, Washington University in Saint Louis, St. Louis, MO 63130, USA. Joseph.Tang.ctr@us.af.mil.
authors.forename: Joseph Kuo-Hsiang
authors.initials: JK
authors.lastname: Tang
authors.affiliation: Departments of Biology and Chemistry, Washington University in Saint Louis, St. Louis, MO 63130, USA. blankenship@wustl.edu.
authors.forename: Robert E
authors.initials: RE
authors.lastname: Blankenship
authors.affiliation: School of Life Sciences, Arizona State University, Tempe, AZ 85287, USA. tgtg.zhao@gmail.com.
authors.forename: Tingting
authors.initials: T
authors.lastname: Zhao
authors.affiliation: School of Life Sciences, Arizona State University, Tempe, AZ 85287, USA. jeffrey.touchman@monsanto.com.
authors.forename: Jeffrey W
authors.initials: JW
authors.lastname: Touchman
authors.affiliation: Division of Natural Sciences, Indiana Wesleyan University, Marion, IN 46953, USA. matthew.sattley@indwes.edu.
authors.forename: W Matthew
authors.initials: WM
authors.lastname: Sattley
keywords: Antarctica; Rhodoferax antarcticus; light-harvesting complex; nitrogen fixation; nitrogenase; photosynthesis gene cluster; psychrophile; purple anoxygenic phototroph