title: Reconstructing a puzzle: existence of cyanophages containing both photosystem-I and photosystem-II gene suites inferred from oceanic metagenomic datasets.
abstract: Cyanobacteria play a key role in marine photosynthesis, which contributes to the global carbon cycle and to the world oxygen supply. Genes encoding the photosystem-II (PSII) reaction centre are found in many cyanophage genomes, and it was suggested that the horizontal transfer of these genes might be involved in increasing phage fitness. Recently, evidence for the existence of phages carrying Photosystem-I (PSI) genes was also reported. Here, using a combination of different marine metagenomic datasets and a unique crossing of the datasets, we now describe the finding of phages that, as in plants and cyanobacteria, contain both PSII and PSI genes. In addition, these phages also contain NADH dehydrogenase genes. The presence of modified PSII and PSI genes in the same viral entities in combination with electron transfer proteins like NAD(P)H dehydrogenase (NDH-1) strongly points to a role in perturbation of the cyanobacterial host photosynthetic electron flow. We therefore suggest that, depending on the physiological condition of the infected cyanobacterial host, the viruses may use different options to maximize survival. The modified PSI may alternate between functioning with PSII in linear electron transfer and contributing to the production of both NADPH and ATP or functioning independently of PSII in cyclic mode via the NDH-1 complex and thus producing only ATP.
authors.affiliation: Faculty of BiologyFaculty of Computer ScienceBioinformatics Knowledge Unit, Lorry I. Lokey Interdisciplinary Center for Life Sciences and Engineering, Technion - Israel Institute of Technology, Haifa 32000, IsraelDepartment of BiologyCenter for Microbial Sciences San Diego State University, San Diego, CA 92182, USADepartment of Biochemistry and Food Chemistry, Plant Physiology and Molecular Biology, University of Turku, FI-20014 Turku, FinlandDepartment of Plant Sciences, Weizmann Institute of Science, Rehovot 76100, IsraelDepartment of Biochemistry, George S. Wise Faculty of Life Sciences, Daniella Rich Institute for Structural Biology, Tel Aviv University, Tel Aviv 69978, Israel.
authors.forename: Ariella
authors.initials: A
authors.lastname: Alperovitch-Lavy
authors.affiliation: Faculty of BiologyFaculty of Computer ScienceBioinformatics Knowledge Unit, Lorry I. Lokey Interdisciplinary Center for Life Sciences and Engineering, Technion - Israel Institute of Technology, Haifa 32000, IsraelDepartment of BiologyCenter for Microbial Sciences San Diego State University, San Diego, CA 92182, USADepartment of Biochemistry and Food Chemistry, Plant Physiology and Molecular Biology, University of Turku, FI-20014 Turku, FinlandDepartment of Plant Sciences, Weizmann Institute of Science, Rehovot 76100, IsraelDepartment of Biochemistry, George S. Wise Faculty of Life Sciences, Daniella Rich Institute for Structural Biology, Tel Aviv University, Tel Aviv 69978, Israel.
authors.forename: Itai
authors.initials: I
authors.lastname: Sharon
authors.affiliation: Faculty of BiologyFaculty of Computer ScienceBioinformatics Knowledge Unit, Lorry I. Lokey Interdisciplinary Center for Life Sciences and Engineering, Technion - Israel Institute of Technology, Haifa 32000, IsraelDepartment of BiologyCenter for Microbial Sciences San Diego State University, San Diego, CA 92182, USADepartment of Biochemistry and Food Chemistry, Plant Physiology and Molecular Biology, University of Turku, FI-20014 Turku, FinlandDepartment of Plant Sciences, Weizmann Institute of Science, Rehovot 76100, IsraelDepartment of Biochemistry, George S. Wise Faculty of Life Sciences, Daniella Rich Institute for Structural Biology, Tel Aviv University, Tel Aviv 69978, Israel.
authors.forename: Forest
authors.initials: F
authors.lastname: Rohwer
authors.affiliation: Faculty of BiologyFaculty of Computer ScienceBioinformatics Knowledge Unit, Lorry I. Lokey Interdisciplinary Center for Life Sciences and Engineering, Technion - Israel Institute of Technology, Haifa 32000, IsraelDepartment of BiologyCenter for Microbial Sciences San Diego State University, San Diego, CA 92182, USADepartment of Biochemistry and Food Chemistry, Plant Physiology and Molecular Biology, University of Turku, FI-20014 Turku, FinlandDepartment of Plant Sciences, Weizmann Institute of Science, Rehovot 76100, IsraelDepartment of Biochemistry, George S. Wise Faculty of Life Sciences, Daniella Rich Institute for Structural Biology, Tel Aviv University, Tel Aviv 69978, Israel.
authors.forename: Eva-Mari
authors.initials: EM
authors.lastname: Aro
authors.affiliation: Faculty of BiologyFaculty of Computer ScienceBioinformatics Knowledge Unit, Lorry I. Lokey Interdisciplinary Center for Life Sciences and Engineering, Technion - Israel Institute of Technology, Haifa 32000, IsraelDepartment of BiologyCenter for Microbial Sciences San Diego State University, San Diego, CA 92182, USADepartment of Biochemistry and Food Chemistry, Plant Physiology and Molecular Biology, University of Turku, FI-20014 Turku, FinlandDepartment of Plant Sciences, Weizmann Institute of Science, Rehovot 76100, IsraelDepartment of Biochemistry, George S. Wise Faculty of Life Sciences, Daniella Rich Institute for Structural Biology, Tel Aviv University, Tel Aviv 69978, Israel.
authors.forename: Fabian
authors.initials: F
authors.lastname: Glaser
authors.affiliation: Faculty of BiologyFaculty of Computer ScienceBioinformatics Knowledge Unit, Lorry I. Lokey Interdisciplinary Center for Life Sciences and Engineering, Technion - Israel Institute of Technology, Haifa 32000, IsraelDepartment of BiologyCenter for Microbial Sciences San Diego State University, San Diego, CA 92182, USADepartment of Biochemistry and Food Chemistry, Plant Physiology and Molecular Biology, University of Turku, FI-20014 Turku, FinlandDepartment of Plant Sciences, Weizmann Institute of Science, Rehovot 76100, IsraelDepartment of Biochemistry, George S. Wise Faculty of Life Sciences, Daniella Rich Institute for Structural Biology, Tel Aviv University, Tel Aviv 69978, Israel.
authors.forename: Ron
authors.initials: R
authors.lastname: Milo
authors.affiliation: Faculty of BiologyFaculty of Computer ScienceBioinformatics Knowledge Unit, Lorry I. Lokey Interdisciplinary Center for Life Sciences and Engineering, Technion - Israel Institute of Technology, Haifa 32000, IsraelDepartment of BiologyCenter for Microbial Sciences San Diego State University, San Diego, CA 92182, USADepartment of Biochemistry and Food Chemistry, Plant Physiology and Molecular Biology, University of Turku, FI-20014 Turku, FinlandDepartment of Plant Sciences, Weizmann Institute of Science, Rehovot 76100, IsraelDepartment of Biochemistry, George S. Wise Faculty of Life Sciences, Daniella Rich Institute for Structural Biology, Tel Aviv University, Tel Aviv 69978, Israel.
authors.forename: Nathan
authors.initials: N
authors.lastname: Nelson
authors.affiliation: Faculty of BiologyFaculty of Computer ScienceBioinformatics Knowledge Unit, Lorry I. Lokey Interdisciplinary Center for Life Sciences and Engineering, Technion - Israel Institute of Technology, Haifa 32000, IsraelDepartment of BiologyCenter for Microbial Sciences San Diego State University, San Diego, CA 92182, USADepartment of Biochemistry and Food Chemistry, Plant Physiology and Molecular Biology, University of Turku, FI-20014 Turku, FinlandDepartment of Plant Sciences, Weizmann Institute of Science, Rehovot 76100, IsraelDepartment of Biochemistry, George S. Wise Faculty of Life Sciences, Daniella Rich Institute for Structural Biology, Tel Aviv University, Tel Aviv 69978, Israel.
authors.forename: Oded
authors.initials: O
authors.lastname: Béjà
mesh_terms: D001435:Bacteriophages / Q000201:enzymology / Q000235:genetics*; D000458:Cyanobacteria / Q000821:virology*; D004579:Electron Transport / Q000235:genetics; D056186:Metagenomics; D008969:Molecular Sequence Data; D009245:NADH Dehydrogenase / Q000235:genetics; D009792:Oceans and Seas; D010084:Oxidation-Reduction; D010788:Photosynthesis / Q000235:genetics; D045331:Photosystem I Protein Complex / Q000235:genetics*; D045332:Photosystem II Protein Complex / Q000235:genetics*; D010802:Phylogeny
chemical_list: D045331:Photosystem I Protein Complex; D045332:Photosystem II Protein Complex; D009245:NADH Dehydrogenase