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Zhu X, Li Z, Tong Y, Chen L, Sun T, Zhang W. From natural to artificial cyanophages: Current progress and application prospects. ENVIRONMENTAL RESEARCH 2023; 223:115428. [PMID: 36746205 DOI: 10.1016/j.envres.2023.115428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Revised: 02/01/2023] [Accepted: 02/03/2023] [Indexed: 06/18/2023]
Abstract
The over proliferation of harmful cyanobacteria and their cyanotoxins resulted in damaged aquatic ecosystem, polluted drinking water and threatened human health. Cyanophages are a kind of viruses that exclusively infect cyanobacteria, which is considered as a potential strategy to deal with cyanobacterial blooms. Nevertheless, the infecting host range and/or lysis efficiency of natural cyanophages is limited, rising the necessity of constructing non-natural cyanophages via artificial modification, design and synthesis to expand their host range and/or efficiency. The paper firstly reviewed representative cyanophages such as P60 with a short latent period of 1.5 h and S-CBS1 having a burst size up to 200 PFU/cell. To explore the in-silico design principles, we critically summarized the interactions between cyanophages and the hosts, indicating modifying the recognized receptors, enhancing the adsorption ability, changing the lysogeny and excluding the defense of hosts are important for artificial cyanophages. The research progress of synthesizing artificial cyanophages were summarized subsequently, raising the importance of developing genetic manipulation technologies and their rescue strategies in the future. Meanwhile, Large-scale preparation of cyanophages for bloom control is a big challenge. The application prospects of artificial cyanophages besides cyanobacteria bloom control like adaptive evolution and phage therapy were discussed at last. The review will promote the design, synthesis and application of cyanophages for cyanobacteria blooms, which may provide new insights for the related water pollution control and ensuring hydrosphere security.
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Affiliation(s)
- Xiaofei Zhu
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, 300072, PR China; Frontier Science Center for Synthetic Biology & Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin, 300072, PR China
| | - Zipeng Li
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Yindong Tong
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Lei Chen
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, 300072, PR China; Frontier Science Center for Synthetic Biology & Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin, 300072, PR China.
| | - Tao Sun
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, 300072, PR China; Frontier Science Center for Synthetic Biology & Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin, 300072, PR China; Center for Biosafety Research and Strategy, Tianjin University, Tianjin, 300072, PR China.
| | - Weiwen Zhang
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, 300072, PR China; Frontier Science Center for Synthetic Biology & Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin, 300072, PR China; Center for Biosafety Research and Strategy, Tianjin University, Tianjin, 300072, PR China
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2
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Dunn AK. Alternative oxidase in bacteria. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2023; 1864:148929. [PMID: 36265564 DOI: 10.1016/j.bbabio.2022.148929] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 09/20/2022] [Accepted: 10/12/2022] [Indexed: 11/06/2022]
Abstract
While alternative oxidase (AOX) was discovered in bacteria in 2003, the expression, function, and evolutionary history of this protein in these important organisms is largely unexplored. To date, expression and functional analysis is limited to studies in the Proteobacteria Novosphingobium aromaticivorans and Vibrio fischeri, where AOX likely plays roles in maintenance of cellular energy homeostasis and supporting responses to cellular stress. This review describes the history of the study of AOX in bacteria, details current knowledge of the predicted biochemical and structural characteristics, distribution, and function of bacterial AOX, and highlights interesting areas for the future study of AOX in bacteria.
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Affiliation(s)
- Anne K Dunn
- Department of Microbiology and Plant Biology, University of Oklahoma, 770 Van Vleet Oval, Norman, OK 73019, USA.
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3
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Foliar Application of Rhodopseudomonas palustris Enhances the Rice Crop Growth and Yield under Field Conditions. PLANTS 2022; 11:plants11192452. [PMID: 36235318 PMCID: PMC9614608 DOI: 10.3390/plants11192452] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 09/09/2022] [Accepted: 09/17/2022] [Indexed: 11/17/2022]
Abstract
Anthropogenic activities causing climate change and other environmental effects are lowering crop yield by deteriorating the growing environment for crops. Rice, a globally important cereal crop, is under production threat due to climate change and land degradation. This research aims to sustainably improve rice growth and yield by using Rhodopseudomonas palustris, a plant growth-promoting bacteria that has recently gained much attention in crop production. The experiment was set up in two fields, one as a control and the other as a PNSB-treated field. The foliar application of treatment was made fortnightly until the end of the vegetative stage. Data on the growth, yield, and antioxidant enzymes were collected weekly. The results of this experiment indicate no significant differences in the plant height, root volume, average grain per panicle, biological yield, grain fertility, and antioxidant enzyme activity between the PNSB-treated and untreated plants. However, a significant increase in the tiller number, leaf chlorophyll content and lodging resistance were noted with PNSB treatment. Likewise, PNSB-treatment significantly increased root length (25%), root dry weight (57%), productive tillers per plants (26%), average grains per plant (38%), grain yield (33%), 1000 grain weight (1.6%), and harvest index (41%). Hence, from this research, it can be concluded that foliar application of PNSB on rice crops under field conditions improves crop growth and yield, although it does not affect antioxidant enzyme activity.
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4
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El-Khoury R, Rak M, Bénit P, Jacobs HT, Rustin P. Cyanide resistant respiration and the alternative oxidase pathway: A journey from plants to mammals. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2022; 1863:148567. [PMID: 35500614 DOI: 10.1016/j.bbabio.2022.148567] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 04/06/2022] [Accepted: 04/18/2022] [Indexed: 12/19/2022]
Abstract
In a large number of organisms covering all phyla, the mitochondrial respiratory chain harbors, in addition to the conventional elements, auxiliary proteins that confer adaptive metabolic plasticity. The alternative oxidase (AOX) represents one of the most studied auxiliary proteins, initially identified in plants. In contrast to the standard respiratory chain, the AOX mediates a thermogenic cyanide-resistant respiration; a phenomenon that has been of great interest for over 2 centuries in that energy is not conserved when electrons flow through it. Here we summarize centuries of studies starting from the early observations of thermogenicity in plants and the identification of cyanide resistant respiration, to the fascinating discovery of the AOX and its current applications in animals under normal and pathological conditions.
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Affiliation(s)
- Riyad El-Khoury
- American University of Beirut Medical Center, Pathology and Laboratory Medicine Department, Cairo Street, Hamra, Beirut, Lebanon
| | - Malgorzata Rak
- Université Paris Cité, Inserm, Maladies neurodéveloppementales et neurovasculaires, F-75019 Paris, France
| | - Paule Bénit
- Université Paris Cité, Inserm, Maladies neurodéveloppementales et neurovasculaires, F-75019 Paris, France
| | - Howard T Jacobs
- Faculty of Medicine and Health Technology, FI-33014, Tampere University, Finland; Institute of Biotechnology, University of Helsinki, Helsinki, Finland.
| | - Pierre Rustin
- Université Paris Cité, Inserm, Maladies neurodéveloppementales et neurovasculaires, F-75019 Paris, France.
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5
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Jiang T, Guo C, Wang M, Wang M, Zhang X, Liu Y, Liang Y, Jiang Y, He H, Shao H, McMinn A. Genome Analysis of Two Novel Synechococcus Phages That Lack Common Auxiliary Metabolic Genes: Possible Reasons and Ecological Insights by Comparative Analysis of Cyanomyoviruses. Viruses 2020; 12:v12080800. [PMID: 32722486 PMCID: PMC7472177 DOI: 10.3390/v12080800] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 07/23/2020] [Accepted: 07/24/2020] [Indexed: 02/01/2023] Open
Abstract
The abundant and widespread unicellular cyanobacteria Synechococcus plays an important role in contributing to global phytoplankton primary production. In the present study, two novel cyanomyoviruses, S-N03 and S-H34 that infected Synechococcus MW02, were isolated from the coastal waters of the Yellow Sea. S-N03 contained a 167,069-bp genome comprising double-stranded DNA with a G + C content of 50.1%, 247 potential open reading frames and 1 tRNA; S-H34 contained a 167,040-bp genome with a G + C content of 50.1%, 246 potential open reading frames and 5 tRNAs. These two cyanophages contain fewer auxiliary metabolic genes (AMGs) than other previously isolated cyanophages. S-H34 in particular, is currently the only known cyanomyovirus that does not contain any AMGs related to photosynthesis. The absence of such common AMGs in S-N03 and S-H34, their distinct evolutionary history and ecological features imply that the energy for phage production might be obtained from other sources rather than being strictly dependent on the maintenance of photochemical ATP under high light. Phylogenetic analysis showed that the two isolated cyanophages clustered together and had a close relationship with two other cyanophages of low AMG content. Comparative genomic analysis, habitats and hosts across 81 representative cyanomyovirus showed that cyanomyovirus with less AMGs content all belonged to Synechococcus phages isolated from eutrophic waters. The relatively small genome size and high G + C content may also relate to the lower AMG content, as suggested by the significant correlation between the number of AMGs and G + C%. Therefore, the lower content of AMG in S-N03 and S-H34 might be a result of viral evolution that was likely shaped by habitat, host, and their genomic context. The genomic content of AMGs in cyanophages may have adaptive significance and provide clues to their evolution.
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Affiliation(s)
- Tong Jiang
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; (T.J.); (M.W.); (M.W.); (X.Z.); (Y.L.); (Y.L.); (Y.J.); (H.H.); (H.S.); (A.M.)
| | - Cui Guo
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; (T.J.); (M.W.); (M.W.); (X.Z.); (Y.L.); (Y.L.); (Y.J.); (H.H.); (H.S.); (A.M.)
- Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China
- Key Lab of Polar Oceanography and Global Ocean Change, Ocean University of China, Qingdao 266003, China
- Correspondence:
| | - Min Wang
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; (T.J.); (M.W.); (M.W.); (X.Z.); (Y.L.); (Y.L.); (Y.J.); (H.H.); (H.S.); (A.M.)
- Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China
- Key Lab of Polar Oceanography and Global Ocean Change, Ocean University of China, Qingdao 266003, China
| | - Meiwen Wang
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; (T.J.); (M.W.); (M.W.); (X.Z.); (Y.L.); (Y.L.); (Y.J.); (H.H.); (H.S.); (A.M.)
| | - Xinran Zhang
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; (T.J.); (M.W.); (M.W.); (X.Z.); (Y.L.); (Y.L.); (Y.J.); (H.H.); (H.S.); (A.M.)
| | - Yundan Liu
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; (T.J.); (M.W.); (M.W.); (X.Z.); (Y.L.); (Y.L.); (Y.J.); (H.H.); (H.S.); (A.M.)
| | - Yantao Liang
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; (T.J.); (M.W.); (M.W.); (X.Z.); (Y.L.); (Y.L.); (Y.J.); (H.H.); (H.S.); (A.M.)
- Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China
- Key Lab of Polar Oceanography and Global Ocean Change, Ocean University of China, Qingdao 266003, China
| | - Yong Jiang
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; (T.J.); (M.W.); (M.W.); (X.Z.); (Y.L.); (Y.L.); (Y.J.); (H.H.); (H.S.); (A.M.)
- Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China
- Key Lab of Polar Oceanography and Global Ocean Change, Ocean University of China, Qingdao 266003, China
| | - Hui He
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; (T.J.); (M.W.); (M.W.); (X.Z.); (Y.L.); (Y.L.); (Y.J.); (H.H.); (H.S.); (A.M.)
- Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China
- Key Lab of Polar Oceanography and Global Ocean Change, Ocean University of China, Qingdao 266003, China
| | - Hongbing Shao
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; (T.J.); (M.W.); (M.W.); (X.Z.); (Y.L.); (Y.L.); (Y.J.); (H.H.); (H.S.); (A.M.)
| | - Andrew McMinn
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; (T.J.); (M.W.); (M.W.); (X.Z.); (Y.L.); (Y.L.); (Y.J.); (H.H.); (H.S.); (A.M.)
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania 7001, Australia
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6
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Johnson LA, Hug LA. Distribution of reactive oxygen species defense mechanisms across domain bacteria. Free Radic Biol Med 2019; 140:93-102. [PMID: 30930298 DOI: 10.1016/j.freeradbiomed.2019.03.032] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 03/06/2019] [Accepted: 03/26/2019] [Indexed: 11/25/2022]
Abstract
Bacteria are the most diverse and numerous organisms on the planet, inhabiting environments from the deep subsurface to particles in clouds. Across this range of conditions, bacteria have evolved a diverse suite of enzymes to mitigate cellular damage from reactive oxygen species (ROS). Here, we review the diversity and distribution of ROS enzymatic defense mechanisms across the domain Bacteria, using both peer-reviewed literature and publicly available genome databases. We describe the specific strategies used by well-characterized organisms in order to highlight differences in oxidative stress responses between aerobic, facultatively anaerobic, and anaerobic lifestyles. We present evidence from genome minimization experiments to suggest that ROS defenses are obligately required for life. This review clarifies the variability in ROS defenses across Bacteria, including the novel diversity found in currently uncharacterized Candidate Phyla.
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Affiliation(s)
- Lisa A Johnson
- Department of Biology, University of Waterloo, Waterloo, Canada
| | - Laura A Hug
- Department of Biology, University of Waterloo, Waterloo, Canada.
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7
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Braakman R. Evolution of cellular metabolism and the rise of a globally productive biosphere. Free Radic Biol Med 2019; 140:172-187. [PMID: 31082508 DOI: 10.1016/j.freeradbiomed.2019.05.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 02/28/2019] [Accepted: 05/02/2019] [Indexed: 01/14/2023]
Abstract
Metabolic processes in cells and chemical processes in the environment are fundamentally intertwined and have evolved in concert for most of Earth's existence. Here I argue that intrinsic properties of cellular metabolism imposed central constraints on the historical trajectories of biopsheric productivity and atmospheric oxygenation. Photosynthesis depends on iron, but iron is highly insoluble under the aerobic conditions produced by oxygenic photosynthesis. These counteracting constraints led to two major stages of Earth oxygenation. After a cyanobacteria-driven biospheric expansion near the Archean-Proterozoic boundary, productivity remained largely restricted to continental boundaries and shallow aquatic environments where weathering inputs made iron more accessible. The anoxic deep open ocean was rich in free iron during the Proterozoic, but this iron was largely inaccessible, partly because an otherwise nutrient-poor ocean was limiting to photosynthesis, but also because a photosynthetic expansion would have quenched its own iron supply. Near the Proterozoic-Phanerozoic boundary, bioenergetics innovations allowed eukaryotic photosynthesis to overcome these interconnected negative feedbacks and begin expanding into the deep open oceans and onto the continents, where nutrients are inherently harder to come by. Key insights into what drove the ecological rise of eukaryotic photosynthesis emerge from analyses of marine Synechococcus and Prochlorococcus, abundant marine picocyanobacteria whose ancestors colonized the oceans in the Neoproterozoic. The reconstructed evolution of this group reveals a sequence of innovations that ultimately produced a form of photosynthesis in Prochlorococcus that is more like that of green plant cells than other cyanobacteria. Innovations increased the energy flux of cells, thereby enhancing their ability to acquire sparse nutrients, and as by-product also increased the production of organic carbon waste. Some of these organic waste products had the ability to chelate iron and make it bioavailable, thereby indirectly pushing the oceans through a transition from an anoxic state rich in free iron to an oxygenated state with organic carbon-bound iron. Resulting conditions (and parallel processes on the continents) in turn led to a series of positive feedbacks that increased the availability of other nutrients, thereby promoting the rise of a globally productive biosphere. In addition to the occurrence of major biospheric expansions, the several hundred million-year periods around the Archean-Proterozoic and Proterozoic-Phanerozoic boundaries share a number of other parallels. Both epochs have also been linked to major carbon cycle perturbations and global glaciations, as well as changes in the nature of plate tectonics and increases in continental exposure and weathering. This suggests the dynamics of life and Earth are intimately intertwined across many levels and that general principles governed transitions in these coupled dynamics at both times in Earth history.
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Affiliation(s)
- Rogier Braakman
- Department of Civil & Environmental Engineering, Massachusetts Institute of Technology, USA; Department of Earth, Atmospheric & Planetary Sciences, Massachusetts Institute of Technology, USA.
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8
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Alternative Oxidase Activity Reduces Stress in Vibrio fischeri Cells Exposed to Nitric Oxide. J Bacteriol 2018; 200:JB.00797-17. [PMID: 29760206 DOI: 10.1128/jb.00797-17] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Accepted: 05/07/2018] [Indexed: 11/20/2022] Open
Abstract
Alternative oxidase (Aox) is a non-energy-conserving respiratory oxidase found in certain eukaryotes and bacteria, whose role in physiology is not entirely clear. Using the genetically tractable bacterium Vibrio fischeri as a model organism, I have identified a role for Aox to reduce levels of stress in cells exposed to oxygen and nitric oxide (NO). In V. fischeri lacking the NO-detoxifying enzyme flavohemoglobin (Hmp), deletion of aox in cells grown in the presence of oxygen and NO results in alterations to the transcriptome that include increases in transcripts mapping to stress-related genes. Using fluorescence-based reporters, I identified corresponding increases in intracellular reactive oxygen species and decreases in membrane integrity in cells lacking aox Under these growth conditions, activity of Aox is linked to a decrease in NADH levels, indicating coupling of Aox activity with NADH dehydrogenase activity. Taken together, these results suggest that Aox functions to indirectly limit production of ferrous iron and damaging hydroxyl radicals, effectively reducing cellular stress during NO exposure.IMPORTANCE Unlike typical respiratory oxidases, alternative oxidase (Aox) does not directly contribute to energy conservation, and its activity would presumably reduce the efficiency of respiration and associated ATP production. Aox has been identified in certain bacteria, a majority of which are marine associated. The presence of Aox in these bacteria poses the interesting question of how Aox function benefits bacterial growth and survival in the ocean. Using the genetically tractable marine bacterium Vibrio fischeri, I have identified a role for Aox in reduction of stress under conditions where electron flux through the aerobic respiratory pathway is inhibited. These results suggest that Aox activity could positively impact longer-term bacterial fitness and survival under stressful environmental conditions.
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9
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Felcmanová K, Lukeš M, Kotabová E, Lawrenz E, Halsey KH, Prášil O. Carbon use efficiencies and allocation strategies in Prochlorococcus marinus strain PCC 9511 during nitrogen-limited growth. PHOTOSYNTHESIS RESEARCH 2017; 134:71-82. [PMID: 28721457 DOI: 10.1007/s11120-017-0418-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Accepted: 07/01/2017] [Indexed: 06/07/2023]
Abstract
We studied cell properties including carbon allocation dynamics in the globally abundant and important cyanobacterium Prochlorococcus marinus strain PCC 9511 grown at three different growth rates in nitrogen-limited continuous cultures. With increasing nitrogen limitation, cellular divinyl chlorophyll a and the functional absorption cross section of Photosystem II decreased, although maximal photosynthetic efficiency of PSII remained unaltered across all N-limited growth rates. Chl-specific gross and net carbon primary production were also invariant with nutrient-limited growth rate, but only 20% of Chl-specific gross carbon primary production was retained in the biomass across all growth rates. In nitrogen-replete cells, 60% of the assimilated carbon was incorporated into the protein pool while only 30% was incorporated into carbohydrates. As N limitation increased, new carbon became evenly distributed between these two pools. While many of these physiological traits are similar to those measured in other algae, there are also distinct differences, particularly the lower overall efficiency of carbon utilization. The latter provides new information needed for understanding and estimating primary production, particularly in the nutrient-limited tropical oceans where P. marinus dominates phytoplankton community composition.
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Affiliation(s)
- Kristina Felcmanová
- Institute of Microbiology, Czech Academy of Sciences, v. v. i., Novohradská 237, Třeboň, 37981, Czech Republic
- Department of Experimental Plant Biology, Faculty of Science, University of South Bohemia, Branišovská 31, České Budějovice, 37005, Czech Republic
| | - Martin Lukeš
- Institute of Microbiology, Czech Academy of Sciences, v. v. i., Novohradská 237, Třeboň, 37981, Czech Republic
- Department of Experimental Plant Biology, Faculty of Science, University of South Bohemia, Branišovská 31, České Budějovice, 37005, Czech Republic
| | - Eva Kotabová
- Institute of Microbiology, Czech Academy of Sciences, v. v. i., Novohradská 237, Třeboň, 37981, Czech Republic
| | - Evelyn Lawrenz
- Institute of Microbiology, Czech Academy of Sciences, v. v. i., Novohradská 237, Třeboň, 37981, Czech Republic
| | - Kimberly H Halsey
- Department of Microbiology, Oregon State University, Nash Hall, Corvallis, OR, 97330, USA
| | - Ondřej Prášil
- Institute of Microbiology, Czech Academy of Sciences, v. v. i., Novohradská 237, Třeboň, 37981, Czech Republic.
- Department of Experimental Plant Biology, Faculty of Science, University of South Bohemia, Branišovská 31, České Budějovice, 37005, Czech Republic.
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10
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Structural insights into the alternative oxidases: are all oxidases made equal? Biochem Soc Trans 2017; 45:731-740. [PMID: 28620034 DOI: 10.1042/bst20160178] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 03/08/2017] [Accepted: 03/10/2017] [Indexed: 01/15/2023]
Abstract
The alternative oxidases (AOXs) are ubiquinol-oxidoreductases that are members of the diiron carboxylate superfamily. They are not only ubiquitously distributed within the plant kingdom but also found in increasing numbers within the fungal, protist, animal and prokaryotic kingdoms. Although functions of AOXs are highly diverse in general, they tend to play key roles in thermogenesis, stress tolerance (through the management of radical oxygen species) and the maintenance of mitochondrial and cellular energy homeostasis. The best structurally characterised AOX is from Trypanosoma brucei In this review, we compare the structure of AOXs, created using homology modelling, from many important species in an attempt to explain differences in activity and sensitivity to AOX inhibitors. We discuss the implications of these findings not only for future structure-based drug design but also for the design of novel AOXs for gene therapy.
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11
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Braakman R, Follows MJ, Chisholm SW. Metabolic evolution and the self-organization of ecosystems. Proc Natl Acad Sci U S A 2017; 114:E3091-E3100. [PMID: 28348231 PMCID: PMC5393222 DOI: 10.1073/pnas.1619573114] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Metabolism mediates the flow of matter and energy through the biosphere. We examined how metabolic evolution shapes ecosystems by reconstructing it in the globally abundant oceanic phytoplankter Prochlorococcus To understand what drove observed evolutionary patterns, we interpreted them in the context of its population dynamics, growth rate, and light adaptation, and the size and macromolecular and elemental composition of cells. This multilevel view suggests that, over the course of evolution, there was a steady increase in Prochlorococcus' metabolic rate and excretion of organic carbon. We derived a mathematical framework that suggests these adaptations lower the minimal subsistence nutrient concentration of cells, which results in a drawdown of nutrients in oceanic surface waters. This, in turn, increases total ecosystem biomass and promotes the coevolution of all cells in the ecosystem. Additional reconstructions suggest that Prochlorococcus and the dominant cooccurring heterotrophic bacterium SAR11 form a coevolved mutualism that maximizes their collective metabolic rate by recycling organic carbon through complementary excretion and uptake pathways. Moreover, the metabolic codependencies of Prochlorococcus and SAR11 are highly similar to those of chloroplasts and mitochondria within plant cells. These observations lead us to propose a general theory relating metabolic evolution to the self-amplification and self-organization of the biosphere. We discuss the implications of this framework for the evolution of Earth's biogeochemical cycles and the rise of atmospheric oxygen.
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Affiliation(s)
- Rogier Braakman
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139;
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Michael J Follows
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Sallie W Chisholm
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139;
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139
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Tang Y, Sun X, Wen T, Liu M, Yang M, Chen X. Implications of terminal oxidase function in regulation of salicylic acid on soybean seedling photosynthetic performance under water stress. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2017; 112:19-28. [PMID: 28024235 DOI: 10.1016/j.plaphy.2016.11.016] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 11/22/2016] [Accepted: 11/22/2016] [Indexed: 05/27/2023]
Abstract
The aim of this study is to investigate whether exogenous application of salicylic acid (SA) could modulate the photosynthetic capacity of soybean seedlings in water stress tolerance, and to clarify the potential functions of terminal oxidase (plastid terminal oxidase (PTOX) and alternative oxidase (AOX)) in SA' s regulation on photosynthesis. The effects of SA and water stress on gas exchange, pigment contents, chlorophyll fluorescence, enzymes (guaiacol peroxidase (POD; EC 1.11.1.7), superoxide dismutase (SOD; EC 1.15.1.1), catalase (CAT; EC 1.11.1.6), ascorbate peroxidase (APX; EC 1.11.1.11) and NADP-malate dehydrogenase (NADP-MDH; EC1.1.1.82)) activity and transcript levels of PTOX, AOX1, AOX2a, AOX2b were examined in a hydroponic cultivation system. Results indicate that water stress significantly decreased the photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (E), pigment contents (Chla + b, Chla/b, Car), maximum quantum yield of PSⅡphotochemistry (Fv/Fm), efficiency of excitation capture of open PSⅡcenter (Fv'/Fm'), quantum efficiency of PSⅡphotochemistry (ΦPSⅡ), photochemical quenching (qP), and increased malondialdehyde (MDA) content and the activity of all the enzymes. SA pretreatment led to significant decreases in Ci and MDA content, and increases in Pn, Gs, E, pigment contents, Fv/Fm, Fv'/Fm', ΦPSⅡ, qP, and the activity of all the enzymes. SA treatment and water stress alone significantly up-regulated the expression of PTOX, AOX1 and AOX2b. SA pretreatment further increased the transcript levels of PTOX and AOX2b of soybean seedling under water stress. These results indicate that SA application alleviates the water stress-induced decrease in photosynthesis may mainly through maintaining a lower reactive oxygen species (ROS) level, a greater PSⅡefficiency, and an enhanced alternative respiration and chlororespiration. PTOX and AOX may play important roles in SA-mediated resistance to water stress.
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Affiliation(s)
- Yanping Tang
- College of Agronomy, Sichuan Agricultural University, No.211, Huimin Road, Gongping Town, Wenjiang District, Chengdu, 611130, Sichuan, China; Agrotechnical Extension Station, Agricultural Bureau of Dazhou City, No.52, Heye Street, Tongchuan District, Dazhou, 635000, Sichuan, China.
| | - Xin Sun
- College of Agronomy, Sichuan Agricultural University, No.211, Huimin Road, Gongping Town, Wenjiang District, Chengdu, 611130, Sichuan, China.
| | - Tao Wen
- College of Agronomy, Sichuan Agricultural University, No.211, Huimin Road, Gongping Town, Wenjiang District, Chengdu, 611130, Sichuan, China.
| | - Mingjie Liu
- College of Agronomy, Sichuan Agricultural University, No.211, Huimin Road, Gongping Town, Wenjiang District, Chengdu, 611130, Sichuan, China
| | - Mingyan Yang
- College of Agronomy, Sichuan Agricultural University, No.211, Huimin Road, Gongping Town, Wenjiang District, Chengdu, 611130, Sichuan, China
| | - Xuefei Chen
- College of Agronomy, Sichuan Agricultural University, No.211, Huimin Road, Gongping Town, Wenjiang District, Chengdu, 611130, Sichuan, China
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Mandel MJ, Dunn AK. Impact and Influence of the Natural Vibrio-Squid Symbiosis in Understanding Bacterial-Animal Interactions. Front Microbiol 2016; 7:1982. [PMID: 28018314 PMCID: PMC5156696 DOI: 10.3389/fmicb.2016.01982] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 11/25/2016] [Indexed: 11/13/2022] Open
Abstract
Animals are colonized by bacteria, and in many cases partners have co-evolved to perform mutually beneficial functions. An exciting and ongoing legacy of the past decade has been an expansion of technology to enable study of natural associations in situ/in vivo. As a result, more symbioses are being examined, and additional details are being revealed for well-studied systems with a focus on the interactions between partners in the native context. With this framing, we review recent literature from the Vibrio fischeri-Euprymna scolopes symbiosis and focus on key studies that have had an impact on understanding bacteria-animal interactions broadly. This is not intended to be a comprehensive review of the system, but rather to focus on particular studies that have excelled at moving from pattern to process in facilitating an understanding of the molecular basis to intriguing observations in the field of host-microbe interactions. In this review we discuss the following topics: processes regulating strain and species specificity; bacterial signaling to host morphogenesis; multiple roles for nitric oxide; flagellar motility and chemotaxis; and efforts to understand unannotated and poorly annotated genes. Overall these studies demonstrate how functional approaches in vivo in a tractable system have provided valuable insight into general principles of microbe-host interactions.
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Affiliation(s)
- Mark J Mandel
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine Chicago, IL, USA
| | - Anne K Dunn
- Department of Microbiology and Plant Biology, University of Oklahoma Norman, OK, USA
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15
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Gómez-Baena G, Domínguez-Martín MA, Donaldson RP, García-Fernández JM, Diez J. Glutamine Synthetase Sensitivity to Oxidative Modification during Nutrient Starvation in Prochlorococcus marinus PCC 9511. PLoS One 2015; 10:e0135322. [PMID: 26270653 PMCID: PMC4535847 DOI: 10.1371/journal.pone.0135322] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 07/21/2015] [Indexed: 11/19/2022] Open
Abstract
Glutamine synthetase plays a key role in nitrogen metabolism, thus the fine regulation of this enzyme in Prochlorococcus, which is especially important in the oligotrophic oceans where this marine cyanobacterium thrives. In this work, we studied the metal-catalyzed oxidation of glutamine synthetase in cultures of Prochlorococcus marinus strain PCC 9511 subjected to nutrient limitation. Nitrogen deprivation caused glutamine synthetase to be more sensitive to metal-catalyzed oxidation (a 36% increase compared to control, non starved samples). Nutrient starvation induced also a clear increase (three-fold in the case of nitrogen) in the concentration of carbonyl derivatives in cell extracts, which was also higher (22%) upon addition of the inhibitor of electron transport, DCMU, to cultures. Our results indicate that nutrient limitations, representative of the natural conditions in the Prochlorococcus habitat, affect the response of glutamine synthetase to oxidative inactivating systems. Implications of these results on the regulation of glutamine synthetase by oxidative alteration prior to degradation of the enzyme in Prochlorococcus are discussed.
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Affiliation(s)
- Guadalupe Gómez-Baena
- Departamento de Bioquímica y Biología Molecular, Edificio Severo Ochoa, Universidad de Córdoba, Córdoba, Spain
- * E-mail:
| | | | - Robert P. Donaldson
- Department of Biological Sciences, The George Washington University, Washington, D.C., United States of America
| | | | - Jesús Diez
- Departamento de Bioquímica y Biología Molecular, Edificio Severo Ochoa, Universidad de Córdoba, Córdoba, Spain
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Abstract
Vibrio fischeri is a bioluminescent, Gram-negative marine bacterium that can be found free living and in a mutualistic association with certain squids and fishes. Over the past decades, the study of V. fischeri has led to important discoveries about bioluminescence, quorum sensing, and the mechanisms that underlie beneficial host-microbe interactions. This chapter highlights what has been learned about metabolic pathways in V. fischeri, and how this information contributes to a broader understanding of the role of bacterial metabolism in host colonization by both beneficial and pathogenic bacteria, as well as in the growth and survival of free-living bacteria.
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Matus-Ortega MG, Salmerón-Santiago KG, Flores-Herrera O, Guerra-Sánchez G, Martínez F, Rendón JL, Pardo JP. The alternative NADH dehydrogenase is present in mitochondria of some animal taxa. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2011; 6:256-63. [DOI: 10.1016/j.cbd.2011.05.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2011] [Revised: 05/07/2011] [Accepted: 05/09/2011] [Indexed: 10/18/2022]
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Sullivan MB, Huang KH, Ignacio-Espinoza JC, Berlin AM, Kelly L, Weigele PR, DeFrancesco AS, Kern SE, Thompson LR, Young S, Yandava C, Fu R, Krastins B, Chase M, Sarracino D, Osburne MS, Henn MR, Chisholm SW. Genomic analysis of oceanic cyanobacterial myoviruses compared with T4-like myoviruses from diverse hosts and environments. Environ Microbiol 2011; 12:3035-56. [PMID: 20662890 PMCID: PMC3037559 DOI: 10.1111/j.1462-2920.2010.02280.x] [Citation(s) in RCA: 245] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
T4-like myoviruses are ubiquitous, and their genes are among the most abundant documented in ocean systems. Here we compare 26 T4-like genomes, including 10 from non-cyanobacterial myoviruses, and 16 from marine cyanobacterial myoviruses (cyanophages) isolated on diverse Prochlorococcus or Synechococcus hosts. A core genome of 38 virion construction and DNA replication genes was observed in all 26 genomes, with 32 and 25 additional genes shared among the non-cyanophage and cyanophage subsets, respectively. These hierarchical cores are highly syntenic across the genomes, and sampled to saturation. The 25 cyanophage core genes include six previously described genes with putative functions (psbA, mazG, phoH, hsp20, hli03, cobS), a hypothetical protein with a potential phytanoyl-CoA dioxygenase domain, two virion structural genes, and 16 hypothetical genes. Beyond previously described cyanophage-encoded photosynthesis and phosphate stress genes, we observed core genes that may play a role in nitrogen metabolism during infection through modulation of 2-oxoglutarate. Patterns among non-core genes that may drive niche diversification revealed that phosphorus-related gene content reflects source waters rather than host strain used for isolation, and that carbon metabolism genes appear associated with putative mobile elements. As well, phages isolated on Synechococcus had higher genome-wide %G+C and often contained different gene subsets (e.g. petE, zwf, gnd, prnA, cpeT) than those isolated on Prochlorococcus. However, no clear diagnostic genes emerged to distinguish these phage groups, suggesting blurred boundaries possibly due to cross-infection. Finally, genome-wide comparisons of both diverse and closely related, co-isolated genomes provide a locus-to-locus variability metric that will prove valuable for interpreting metagenomic data sets.
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McDonald AE, Ivanov AG, Bode R, Maxwell DP, Rodermel SR, Hüner NPA. Flexibility in photosynthetic electron transport: the physiological role of plastoquinol terminal oxidase (PTOX). BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1807:954-67. [PMID: 21056542 DOI: 10.1016/j.bbabio.2010.10.024] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2010] [Revised: 10/27/2010] [Accepted: 10/29/2010] [Indexed: 11/27/2022]
Abstract
Oxygenic photosynthesis depends on a highly conserved electron transport system, which must be particularly dynamic in its response to environmental and physiological changes, in order to avoid an excess of excitation energy and subsequent oxidative damage. Apart from cyclic electron flow around PSII and around PSI, several alternative electron transport pathways exist including a plastoquinol terminal oxidase (PTOX) that mediates electron flow from plastoquinol to O(2). The existence of PTOX was first hypothesized in 1982 and this was verified years later based on the discovery of a non-heme, di-iron carboxylate protein localized to thylakoid membranes that displayed sequence similarity to the mitochondrial alternative oxidase. The absence of this protein renders higher plants susceptible to excitation pressure dependant variegation combined with impaired carotenoid synthesis. Chloroplasts, as well as other plastids (i.e. etioplasts, amyloplasts and chromoplasts), fail to assemble organized internal membrane structures correctly, when exposed to high excitation pressure early in development. While the role of PTOX in plastid development is established, its physiological role under stress conditions remains equivocal and we postulate that it serves as an alternative electron sink under conditions where the acceptor side of PSI is limited. The aim of this review is to provide an overview of the past achievements in this field and to offer directions for future investigative efforts. Plastoquinol terminal oxidase (PTOX) is involved in an alternative electron transport pathway that mediates electron flow from plastoquinol to O(2). This article is part of a Special Issue entitled: Regulation of Electron Transport in Chloroplasts.
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Affiliation(s)
- Allison E McDonald
- Department of Biology, Wilfrid Laurier University, Science Building, 75 University Avenue West, Waterloo, Ontario, Canada N2L 3C5.
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20
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21
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Dunn AK, Karr EA, Wang Y, Batton AR, Ruby EG, Stabb EV. The alternative oxidase (AOX) gene in Vibrio fischeri is controlled by NsrR and upregulated in response to nitric oxide. Mol Microbiol 2010; 77:44-55. [PMID: 20487270 DOI: 10.1111/j.1365-2958.2010.07194.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Alternative oxidase (AOX) is a respiratory oxidase found in certain eukaryotes and bacteria; however, its role in bacterial physiology is unclear. Exploiting the genetic tractability of the bacterium Vibrio fischeri, we explore the regulation of aox expression and AOX function. Using quantitative PCR and reporter assays, we demonstrate that aox expression is induced in the presence of nitric oxide (NO), and that the NO-responsive regulatory protein NsrR mediates the response. We have identified key amino acid residues important for NsrR function and experimentally confirmed a bioinformatically predicted NsrR binding site upstream of aox. Microrespirometry demonstrated that oxygen consumption by V. fischeri CydAB quinol oxidase is inhibited by NO treatment, whereas oxygen consumption by AOX is less sensitive to NO. NADH oxidation assays using inverted membrane vesicles confirmed that NO directly inhibits CydAB, and that AOX is resistant to NO inhibition. These results indicate a role for V. fischeri AOX in aerobic respiration during NO stress.
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Affiliation(s)
- Anne K Dunn
- Department of Botany and Microbiology, University of Oklahoma, Norman, OK 73019, USA.
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22
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Kido Y, Sakamoto K, Nakamura K, Harada M, Suzuki T, Yabu Y, Saimoto H, Yamakura F, Ohmori D, Moore A, Harada S, Kita K. Purification and kinetic characterization of recombinant alternative oxidase from Trypanosoma brucei brucei. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1797:443-50. [DOI: 10.1016/j.bbabio.2009.12.021] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2009] [Revised: 12/23/2009] [Accepted: 12/25/2009] [Indexed: 10/20/2022]
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23
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Albury MS, Elliott C, Moore AL. Towards a structural elucidation of the alternative oxidase in plants. PHYSIOLOGIA PLANTARUM 2009; 137:316-27. [PMID: 19719482 DOI: 10.1111/j.1399-3054.2009.01270.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
In addition to the conventional cytochrome c oxidase, mitochondria of all plants studied to date contain a second cyanide-resistant terminal oxidase or alternative oxidase (AOX). The AOX is located in the inner mitochondrial membrane and branches from the cytochrome pathway at the level of the quinone pool. It is non-protonmotive and couples the oxidation of ubiquinone to the reduction of oxygen to water. For many years, the AOX was considered to be confined to plants, fungi and a small number of protists. Recently, it has become apparent that the AOX occurs in wide range of organisms including prokaryotes and a moderate number of animal species. In this paper, we provide an overview of general features and current knowledge available about the AOX with emphasis on structure, the active site and quinone-binding site. Characterisation of the AOX has advanced considerably over recent years with information emerging about the role of the protein, regulatory regions and functional sites. The large number of sequences available is now enabling us to obtain a clearer picture of evolutionary origins and diversity.
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Affiliation(s)
- Mary S Albury
- Division of Biochemistry and Biomedical Sciences, School of Life Sciences, University of Sussex, Falmer, Brighton BN19QG, UK
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24
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Hansen LD, Thomas NR, Arnholdt-Schmitt B. Temperature responses of substrate carbon conversion efficiencies and growth rates of plant tissues. PHYSIOLOGIA PLANTARUM 2009; 137:446-58. [PMID: 19843241 DOI: 10.1111/j.1399-3054.2009.01287.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Growth rates of plant tissues depend on both the respiration rate and the efficiency with which carbon is incorporated into new structural biomass. Calorespirometric measurement of respiratory heat and CO2 rates, from which both efficiency and growth rate can be calculated, is a well established method for determining the effects of rapid temperature changes on the respiratory and growth properties of plant tissues. The effect of the alternative oxidase/cytochrome oxidase activity ratio on efficiency is calculated from first principles. Data on the temperature dependence of the substrate carbon conversion efficiency are tabulated. These data show that epsilon is maximum and approximately constant through the optimum growth temperature range and decreases rapidly as temperatures approach temperature limits to growth. The width of the maximum and the slopes of decreasing epsilon at high and low temperatures vary greatly with species, cultivars and accessions.
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Affiliation(s)
- Lee D Hansen
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84602, USA. Lee
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25
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McDonald AE, Vanlerberghe GC, Staples JF. Alternative oxidase in animals: unique characteristics and taxonomic distribution. ACTA ACUST UNITED AC 2009; 212:2627-34. [PMID: 19648408 DOI: 10.1242/jeb.032151] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Alternative oxidase (AOX), a ubiquinol oxidase, introduces a branch point into the respiratory electron transport chain, bypassing complexes III and IV and resulting in cyanide-resistant respiration. Previously, AOX was thought to be limited to plants and some fungi and protists but recent work has demonstrated the presence of AOX in most kingdoms of life, including animals. In the present study we identified AOX in 28 animal species representing nine phyla. This expands the known taxonomic distribution of AOX in animals by 10 species and two phyla. Using bioinformatics we found AOX gene sequences in members of the animal phyla Porifera, Placozoa, Cnidaria, Mollusca, Annelida, Nematoda, Echinodermata, Hemichordata and Chordata. Using reverse-transcriptase polymerase chain reaction (RT-PCR) with degenerate primers designed to recognize conserved regions of animal AOX, we demonstrated that AOX genes are transcribed in several animals from different phyla. An analysis of full-length AOX sequences revealed an amino acid motif in the C-terminal region of the protein that is unique to animal AOXs. Animal AOX also lacks an N-terminal cysteine residue that is known to be important for AOX enzyme regulation in plants. We conclude that the presence of AOX is the ancestral state in animals and hypothesize that its absence in some lineages, including vertebrates, is due to gene loss events.
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Affiliation(s)
- Allison E McDonald
- Department of Biology, The University of Western Ontario, London, Ontario, Canada N6A 5B7.
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Millard AD, Zwirglmaier K, Downey MJ, Mann NH, Scanlan DJ. Comparative genomics of marine cyanomyoviruses reveals the widespread occurrence of Synechococcus host genes localized to a hyperplastic region: implications for mechanisms of cyanophage evolution. Environ Microbiol 2009; 11:2370-87. [PMID: 19508343 DOI: 10.1111/j.1462-2920.2009.01966.x] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The vast majority of cyanophages isolated to date are cyanomyoviruses, a group related to bacteriophage T4. Comparative genome analysis of five cyanomyoviruses, including a newly sequenced cyanophage S-RSM4, revealed a 'core genome' of 64 genes, the majority of which are also found in other T4-like phages. Subsequent comparative genomic hybridization analysis using a pilot microarray showed that a number of 'host' genes are widespread in cyanomyovirus isolates. Furthermore, a hyperplastic region was identified between genes g15-g18, within a highly conserved structural gene module, which contained a variable number of inserted genes that lacked conservation in gene order. Several of these inserted genes were host-like and included ptoX, gnd, zwf and petE encoding plastoquinol terminal oxidase, 6-phosphogluconate dehydrogenase, glucose 6-phosphate dehydrogenase and plastocyanin respectively. Phylogenetic analyses suggest that these genes were acquired independently of each other, even though they have become localized within the same genomic region. This hyperplastic region contains no detectable sequence features that might be mechanistically involved with the acquisition of host-like genes, but does appear to be a site specifically associated with the acquisition process and may represent a novel facet of the evolution of marine cyanomyoviruses.
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Affiliation(s)
- Andrew D Millard
- Department of Biological Sciences, University of Warwick, Gibbet Hill Road, Coventry, UK.
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27
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Scanlan DJ, Ostrowski M, Mazard S, Dufresne A, Garczarek L, Hess WR, Post AF, Hagemann M, Paulsen I, Partensky F. Ecological genomics of marine picocyanobacteria. Microbiol Mol Biol Rev 2009; 73:249-99. [PMID: 19487728 PMCID: PMC2698417 DOI: 10.1128/mmbr.00035-08] [Citation(s) in RCA: 446] [Impact Index Per Article: 29.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Marine picocyanobacteria of the genera Prochlorococcus and Synechococcus numerically dominate the picophytoplankton of the world ocean, making a key contribution to global primary production. Prochlorococcus was isolated around 20 years ago and is probably the most abundant photosynthetic organism on Earth. The genus comprises specific ecotypes which are phylogenetically distinct and differ markedly in their photophysiology, allowing growth over a broad range of light and nutrient conditions within the 45 degrees N to 40 degrees S latitudinal belt that they occupy. Synechococcus and Prochlorococcus are closely related, together forming a discrete picophytoplankton clade, but are distinguishable by their possession of dissimilar light-harvesting apparatuses and differences in cell size and elemental composition. Synechococcus strains have a ubiquitous oceanic distribution compared to that of Prochlorococcus strains and are characterized by phylogenetically discrete lineages with a wide range of pigmentation. In this review, we put our current knowledge of marine picocyanobacterial genomics into an environmental context and present previously unpublished genomic information arising from extensive genomic comparisons in order to provide insights into the adaptations of these marine microbes to their environment and how they are reflected at the genomic level.
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Affiliation(s)
- D J Scanlan
- Department of Biological Sciences, University of Warwick, Coventry CV4 7AL, United Kingdom.
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28
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Wang J, Sommerfeld M, Hu Q. Occurrence and environmental stress responses of two plastid terminal oxidases in Haematococcus pluvialis (Chlorophyceae). PLANTA 2009; 230:191-203. [PMID: 19408010 DOI: 10.1007/s00425-009-0932-4] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2009] [Accepted: 04/13/2009] [Indexed: 05/06/2023]
Abstract
The plastid terminal oxidase (PTOX) is a plastoquinol oxidase involved in carotenoid biosynthesis in higher plants, and may also represent the elusive oxidase in chlororespiration. Haematococcus pluvialis is a green alga that has the ability to synthesize and accumulate large amounts of the red carotenoid astaxanthin (ca. 2% of dry weight) under various stress conditions. However, the occurrence and function of PTOX in astaxanthin synthesis and the stress response in this organism is unknown. In this study, two ptox cDNAs were cloned and sequenced from H. pluvialis and were designated as ptox1 and ptox2. Genome sequence analysis and database searching revealed that duplication of PTOX gene occurred in certain eukaryotic algae, but not in cyanobacteria and higher plants. The physiological and biochemical evidence indicated that PTOX is involved in astaxanthin synthesis and plays a critical protective role against stress. Analysis of the transcriptional expression of the PTOXs and phytoene desaturase gene further suggests that it may be PTOX1 rather than PTOX2 that is co-regulated with astaxanthin synthesis. The fact that the changes in transcripts of ptoxs in response to high light and other stressors and the differential expression of ptox1 and ptox2, suggests that PTOX, coupled with astaxanthin synthesis pathway, exerts broad, yet undefined functions in addition to those identified in higher plants.
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Affiliation(s)
- Jiangxin Wang
- Department of Applied Biological Sciences, Arizona State University, Polytechnic Campus, 7001 E. Williams Field Road, Mesa, AZ 85212, USA
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29
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Affiliation(s)
- Amel Latifi
- Aix-Marseille Université and Laboratoire de Chimie Bactérienne, CNRS-UPR9043, Marseille, France.
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McDonald AE. Alternative oxidase: an inter-kingdom perspective on the function and regulation of this broadly distributed 'cyanide-resistant' terminal oxidase. FUNCTIONAL PLANT BIOLOGY : FPB 2008; 35:535-552. [PMID: 32688810 DOI: 10.1071/fp08025] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2008] [Accepted: 07/11/2008] [Indexed: 06/11/2023]
Abstract
Alternative oxidase (AOX) is a terminal quinol oxidase located in the respiratory electron transport chain that catalyses the oxidation of quinol and the reduction of oxygen to water. However, unlike the cytochrome c oxidase respiratory pathway, the AOX pathway moves fewer protons across the inner mitochondrial membrane to generate a proton motive force that can be used to synthesise ATP. The energy passed to AOX is dissipated as heat. This appears to be very wasteful from an energetic perspective and it is likely that AOX fulfils some physiological function(s) that makes up for its apparent energetic shortcomings. An examination of the known taxonomic distribution of AOX and the specific organisms in which AOX has been studied has been used to explore themes pertaining to AOX function and regulation. A comparative approach was used to examine AOX function as it relates to the biochemical function of the enzyme as a quinol oxidase and associated topics, such as enzyme structure, catalysis and transcriptional expression and post-translational regulation. Hypotheses that have been put forward about the physiological function(s) of AOX were explored in light of some recent discoveries made with regard to species that contain AOX. Fruitful areas of research for the AOX community in the future have been highlighted.
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Affiliation(s)
- Allison E McDonald
- Department of Biology, The University of Western Ontario, Biological and Geological Sciences Building, London, Ontario N6A 5B7, Canada. Email
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31
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Two zinc-cluster transcription factors control induction of alternative oxidase in Neurospora crassa. Genetics 2008; 177:1997-2006. [PMID: 18073419 DOI: 10.1534/genetics.107.078212] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The alternative oxidase transfers electrons from ubiquinol to molecular oxygen, providing a mechanism for bypassing the later steps of the standard cytochrome-mediated electron transport chain. The enzyme is found in an array of organisms and in many cases is known to be produced in response to perturbations of the standard chain. Alternative oxidase is encoded in the nucleus but functions in the inner mitochondrial membrane. This implies the existence of a retrograde regulation pathway for communicating from the mitochondrion to the nucleus to induce alternative oxidase expression. Previous studies on alternative oxidase in fungi and plants have shown that a number of genes are required for expression of the enzyme, but the identity of these genes has remained elusive. By gene rescue we have now shown that the aod-2 and aod-5 genes of Neurospora crassa encode transcription factors of the zinc-cluster family. Electrophoretic mobility shift assays show that the DNA-binding domains of the AOD2 and AOD5 proteins act in tandem to bind a sequence element in the alternative oxidase gene promoter that is required for expression. Both proteins contain potential PAS domains near their C terminus, which are found primarily in proteins involved in signal transduction.
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Bailey S, Melis A, Mackey KRM, Cardol P, Finazzi G, van Dijken G, Berg GM, Arrigo K, Shrager J, Grossman A. Alternative photosynthetic electron flow to oxygen in marine Synechococcus. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2008; 1777:269-76. [PMID: 18241667 DOI: 10.1016/j.bbabio.2008.01.002] [Citation(s) in RCA: 141] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2007] [Revised: 12/18/2007] [Accepted: 01/10/2008] [Indexed: 11/17/2022]
Abstract
Cyanobacteria dominate the world's oceans where iron is often barely detectable. One manifestation of low iron adaptation in the oligotrophic marine environment is a decrease in levels of iron-rich photosynthetic components, including the reaction center of photosystem I and the cytochrome b6f complex [R.F. Strzepek and P.J. Harrison, Photosynthetic architecture differs in coastal and oceanic diatoms, Nature 431 (2004) 689-692.]. These thylakoid membrane components have well characterised roles in linear and cyclic photosynthetic electron transport and their low abundance creates potential impediments to photosynthetic function. Here we show that the marine cyanobacterium Synechococcus WH8102 exhibits significant alternative electron flow to O2, a potential adaptation to the low iron environment in oligotrophic oceans. This alternative electron flow appears to extract electrons from the intersystem electron transport chain, prior to photosystem I. Inhibitor studies demonstrate that a propyl gallate-sensitive oxidase mediates this flow of electrons to oxygen, which in turn alleviates excessive photosystem II excitation pressure that can often occur even at relatively low irradiance. These findings are also discussed in the context of satisfying the energetic requirements of the cell when photosystem I abundance is low.
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Affiliation(s)
- Shaun Bailey
- The Carnegie Institution, Department of Plant Biology, 260 Panama Street, Stanford, CA 94305, USA.
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Quesada A, Guijo MI, Merchán F, Blázquez B, Igeño MI, Blasco R. Essential role of cytochrome bd-related oxidase in cyanide resistance of Pseudomonas pseudoalcaligenes CECT5344. Appl Environ Microbiol 2007; 73:5118-24. [PMID: 17574992 PMCID: PMC1950984 DOI: 10.1128/aem.00503-07] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2007] [Accepted: 06/08/2007] [Indexed: 11/20/2022] Open
Abstract
Pseudomonas pseudoalcaligenes CECT5344 grows in minimal medium containing cyanide as the sole nitrogen source. Under these conditions, an O2-dependent respiration highly resistant to cyanide was detected in cell extracts. The structural genes for the cyanide-resistant terminal oxidase, cioA and cioB, are clustered and encode the integral membrane proteins that correspond to subunits I and II of classical cytochrome bd, although the presence of heme d in the membrane could not be detected by difference spectra. The cio operon from P. pseudoalcaligenes presents a singular organization, starting upstream of cioAB by the coding sequence of a putative ferredoxin-dependent sulfite or nitrite reductase and spanning downstream two additional open reading frames that encode uncharacterized gene products. PCR amplifications of RNA (reverse transcription-PCR) indicated the cyanide-dependent up-regulation and cotranscription along the operon. The targeted disruption of cioA eliminates both the expression of the cyanide-stimulated respiratory activity and the growth with cyanide as the nitrogen source, which suggests a critical role of this cytochrome bd-related oxidase in the metabolism of cyanide by P. pseudoalcaligenes CECT5344.
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Affiliation(s)
- Alberto Quesada
- Departamento de Bioquímica, Biología Molecular y Genética, Facultad de Veterinaria, Avda. de la Universidad s/n, 10071-Cáceres, España.
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Weigele PR, Pope WH, Pedulla ML, Houtz JM, Smith AL, Conway JF, King J, Hatfull GF, Lawrence JG, Hendrix RW. Genomic and structural analysis of Syn9, a cyanophage infecting marineProchlorococcusandSynechococcus. Environ Microbiol 2007; 9:1675-95. [PMID: 17564603 DOI: 10.1111/j.1462-2920.2007.01285.x] [Citation(s) in RCA: 142] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cyanobacteriophage Syn9 is a large, contractile-tailed bacteriophage infecting the widespread, numerically dominant marine cyanobacteria of the genera Prochlorococcus and Synechococcus. Its 177,300 bp genome sequence encodes 226 putative proteins and six tRNAs. Experimental and computational analyses identified genes likely involved in virion formation, nucleotide synthesis, and DNA replication and repair. Syn9 shows significant mosaicism when compared with related cyanophages S-PM2, P-SSM2 and P-SSM4, although shared genes show strong purifying selection and evidence for large population sizes relative to other phages. Related to coliphage T4 - which shares 19% of Syn9's genes - Syn9 shows evidence for different patterns of DNA replication and uses homologous proteins to assemble capsids with a different overall structure that shares topology with phage SPO1 and herpes virus. Noteworthy bacteria-related sequences in the Syn9 genome potentially encode subunits of the photosynthetic reaction centre, electron transport proteins, three pentose pathway enzymes and two tryptophan halogenases. These genes suggest that Syn9 is well adapted to the physiology of its photosynthetic hosts and may affect the evolution of these sequences within marine cyanobacteria.
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Affiliation(s)
- Peter R Weigele
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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Chae MS, Lin CC, Kessler KE, Nargang CE, Tanton LL, Hahn LB, Nargang FE. Identification of an alternative oxidase induction motif in the promoter region of the aod-1 gene in Neurospora crassa. Genetics 2007; 175:1597-606. [PMID: 17237510 PMCID: PMC1855127 DOI: 10.1534/genetics.106.068635] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The nuclear aod-1 gene of Neurospora crassa encodes the alternative oxidase and is induced when the standard cytochrome-mediated respiratory chain of mitochondria is inhibited. To study elements of the pathway responsible for alternative oxidase induction, we generated a series of mutations in the region upstream from the aod-1 structural gene and transformed the constructs into an aod-1 mutant strain. Transformed conidia were plated on media containing antimycin A, which inhibits the cytochrome-mediated electron transport chain so that only cells expressing alternative oxidase will grow. Using this functional in vivo assay, we identified an alternative oxidase induction motif (AIM) that is required for efficient expression of aod-1. The AIM sequence consists of two CGG repeats separated by 7 bp and is similar to sequences known to be bound by members of the Zn(II)2Cys6 binuclear cluster family of transcription factors. The AIM motif appears to be conserved in other species found in the order Sordariales.
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Affiliation(s)
- Michael S Chae
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
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Steglich C, Futschik M, Rector T, Steen R, Chisholm SW. Genome-wide analysis of light sensing in Prochlorococcus. J Bacteriol 2006; 188:7796-806. [PMID: 16980454 PMCID: PMC1636322 DOI: 10.1128/jb.01097-06] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Prochlorococcus MED4 has, with a total of only 1,716 annotated protein-coding genes, the most compact genome of a free-living photoautotroph. Although light quality and quantity play an important role in regulating the growth rate of this organism in its natural habitat, the majority of known light-sensing proteins are absent from its genome. To explore the potential for light sensing in this phototroph, we measured its global gene expression pattern in response to different light qualities and quantities by using high-density Affymetrix microarrays. Though seven different conditions were tested, only blue light elicited a strong response. In addition, hierarchical clustering revealed that the responses to high white light and blue light were very similar and different from that of the lower-intensity white light, suggesting that the actual sensing of high light is mediated via a blue-light receptor. Bacterial cryptochromes seem to be good candidates for the blue-light sensors. The existence of a signaling pathway for the redox state of the photosynthetic electron transport chain was suggested by the presence of genes that responded similarly to red and blue light as well as genes that responded to the addition of DCMU [3-(3,4-dichlorophenyl)-1,1-N-N'-dimethylurea], a specific inhibitor of photosystem II-mediated electron transport.
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Affiliation(s)
- Claudia Steglich
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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McDonald AE, Vanlerberghe GC. Origins, evolutionary history, and taxonomic distribution of alternative oxidase and plastoquinol terminal oxidase. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2006; 1:357-64. [PMID: 20483267 DOI: 10.1016/j.cbd.2006.08.001] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2006] [Revised: 08/01/2006] [Accepted: 08/05/2006] [Indexed: 10/24/2022]
Abstract
Alternative oxidase (AOX) and plastoquinol terminal oxidase (PTOX) are related quinol oxidases associated with respiratory and photosynthetic electron transport chains, respectively. Contrary to previous belief, AOX is present in numerous animal phyla, as well as heterotrophic and marine phototrophic proteobacteria. PTOX appears limited to organisms capable of oxygenic photosynthesis, including cyanobacteria, algae and plants. We propose that both oxidases originated in prokaryotes from a common ancestral di-iron carboxylate protein that diversified to AOX within ancient proteobacteria and PTOX within ancient cyanobacteria. Each then entered the eukaryotic lineage separately; AOX by the endosymbiotic event that gave rise to mitochondria and later PTOX by the endosymbiotic event that gave rise to chloroplasts. Both oxidases then spread through the eukaryotic domain by vertical inheritance, as well as by secondary and potentially tertiary endosymbiotic events.
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Affiliation(s)
- Allison E McDonald
- Department of Life Sciences and Department of Cell and Systems Biology, University of Toronto Scarborough, Toronto, Canada
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Umbach AL, Ng VS, Siedow JN. Regulation of plant alternative oxidase activity: A tale of two cysteines. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2006; 1757:135-42. [PMID: 16457775 DOI: 10.1016/j.bbabio.2005.12.005] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2005] [Revised: 12/14/2005] [Accepted: 12/19/2005] [Indexed: 11/21/2022]
Abstract
Two Cys residues, Cys(I) and Cys(II), are present in most plant alternative oxidases (AOXs). Cys(I) inactivates AOX by forming a disulfide bond with the corresponding Cys(I) residue on the adjacent subunit of the AOX homodimer. When reduced, Cys(I) associates with alpha-keto acids, such as pyruvate, to activate AOX, an effect mimicked by charged amino acid substitutions at the Cys(I) site. Cys(II) may also be a site of AOX activity regulation, through interaction with the small alpha-keto acid, glyoxylate. Comparison of Arabidopsis AOX1a (AtAOX1a) mutants with single or double substitutions at Cys(I) and Cys(II) confirmed that glyoxylate interacted with either Cys, while the effect of pyruvate (or succinate for AtAOX1a substituted with Ala at Cys(I)) was limited to Cys(I). A variety of Cys(II) substitutions constitutively activated AtAOX1a, indicating that neither the catalytic site nor, unlike at Cys(I), charge repulsion is involved. Independent effects at each Cys were suggested by lack of Cys(II) substitution interference with pyruvate stimulation at Cys(I), and close to additive activation at the two sites. However, results obtained using diamide treatment to covalently link the AtAOX1a subunits by the disulfide bond indicated that Cys(I) must be in the reduced state for activation at Cys(II) to occur.
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Affiliation(s)
- Ann L Umbach
- DCMB Group/Biology Department, Box 91000, Duke University, Durham, NC 27708-1000, USA.
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Affiliation(s)
- Nobutada Kimura
- Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology (AIST)
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Abstract
Although genomics has classically focused on pure, easy-to-obtain samples, such as microbes that grow readily in culture or large animals and plants, these organisms represent only a fraction of the living or once-living organisms of interest. Many species are difficult to study in isolation because they fail to grow in laboratory culture, depend on other organisms for critical processes, or have become extinct. Methods that are based on DNA sequencing circumvent these obstacles, as DNA can be isolated directly from living or dead cells in various contexts. Such methods have led to the emergence of a new field, which is referred to as metagenomics.
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Affiliation(s)
- Susannah Green Tringe
- Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, California 94598, USA
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Abstract
Recent advances in shotgun sequencing and computational methods for genome assembly have advanced the field of metagenomics, the culture-independent cloning and analysis of microbial DNA extracted directly from an environmental sample, to provide glimpses into the life of uncultured microorganisms. More than 99% of prokaryotes in the environment cannot be cultured in the laboratory, a phenomenon that limits our understanding of microbial physiology, genetics, and community ecology. One way around this problem is metagenomics, the culture-independent cloning and analysis of microbial DNA extracted directly from an environmental sample. Recent advances in shotgun sequencing and computational methods for genome assembly have advanced the field of metagenomics to provide glimpses into the life of uncultured microorganisms.
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Affiliation(s)
- Patrick D Schloss
- Department of Plant Pathology, University of Wisconsin, Madison, WI 53706, USA
| | - Jo Handelsman
- Department of Plant Pathology, University of Wisconsin, Madison, WI 53706, USA
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Abstract
Different industries have different motivations to probe the enormous resource that is uncultivated microbial diversity. Currently, there is a global political drive to promote white (industrial) biotechnology as a central feature of the sustainable economic future of modern industrialized societies. This requires the development of novel enzymes, processes, products and applications. Metagenomics promises to provide new molecules with diverse functions, but ultimately, expression systems are required for any new enzymes and bioactive molecules to become an economic success. This review highlights industrial efforts and achievements in metagenomics.
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Affiliation(s)
- Patrick Lorenz
- BRAIN AG, Darmstaedterstrasse 34, 64673 Zwingenberg, Germany.
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