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Wang Y, Liu J, Yi Y, Zhu L, Liu M, Zhang Z, Xie Q, Jiang L. Insights into the synthesis, engineering, and functions of microbial pigments in Deinococcus bacteria. Front Microbiol 2024; 15:1447785. [PMID: 39119139 PMCID: PMC11306087 DOI: 10.3389/fmicb.2024.1447785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2024] [Accepted: 07/05/2024] [Indexed: 08/10/2024] Open
Abstract
The ability of Deinococcus bacteria to survive in harsh environments, such as high radiation, extreme temperature, and dryness, is mainly attributed to the generation of unique pigments, especially carotenoids. Although the limited number of natural pigments produced by these bacteria restricts their industrial potential, metabolic engineering and synthetic biology can significantly increase pigment yield and expand their application prospects. In this study, we review the properties, biosynthetic pathways, and functions of key enzymes and genes related to these pigments and explore strategies for improving pigment production through gene editing and optimization of culture conditions. Additionally, studies have highlighted the unique role of these pigments in antioxidant activity and radiation resistance, particularly emphasizing the critical functions of deinoxanthin in D. radiodurans. In the future, Deinococcus bacterial pigments will have broad application prospects in the food industry, drug production, and space exploration, where they can serve as radiation indicators and natural antioxidants to protect astronauts' health during long-term space flights.
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Affiliation(s)
- Yuxian Wang
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing, China
| | - Jiayu Liu
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing, China
| | - Yuanyang Yi
- Institute of Applied Microbiology, Xinjiang Academy of Agricultural Sciences/ Xinjiang Key Laboratory of Special Environmental Microbiology, Urumqi, China
- College of Life Sciences, Xinjiang Normal University, Urumqi, China
| | - Liying Zhu
- School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing, China
| | - Minghui Liu
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing, China
| | - Zhidong Zhang
- Institute of Applied Microbiology, Xinjiang Academy of Agricultural Sciences/ Xinjiang Key Laboratory of Special Environmental Microbiology, Urumqi, China
| | - Qiong Xie
- China Astronaut Research and Training Center, Beijing, China
| | - Ling Jiang
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing, China
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Food Science and Light Industry, Nanjing Tech University, Nanjing, China
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Jiang W, Sun J, Gao H, Tang Y, Wang C, Jiang Y, Zhang W, Xin F, Jiang M. Carotenoids production and genome analysis of a novel carotenoid producing Rhodococcus aetherivorans N1. Enzyme Microb Technol 2023; 164:110190. [PMID: 36603321 DOI: 10.1016/j.enzmictec.2022.110190] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 12/26/2022] [Accepted: 12/27/2022] [Indexed: 12/31/2022]
Abstract
Carotenoids are a series of natural pigments with unique structure and physiological functions. In this study, a novel Rhodococcus aetherivorans strain N1 was discovered, which can produce 6.4 mg/g carotenoids including β-carotene, zeaxanthin and isorenieratene from glucose. Moreover, strain N1 can directly produce 3.0 mg/g carotenoids from the undetoxified straw hydrolysate, representing the highest carotenoids production from the undetoxified lignocellulosic hydrolysate. The crude carotenoid extracts of strain N1 showed efficient free radical scavenging activity and stability. Strain N1 has complete methylerythritol 4-phosphate (MEP) pathway and related genes for carotenoid synthesis, especially the rare aromatic carotenoid of isorenieratene. Genomic comparison between strain N1 and other carotenoid producing Rhodococcus sp. strains showed the conservatism and universality of carotenoids synthesis gene. These results proved that R. aetherivorans strain N1 can serve as a promising producer for the industrialization of carotenoid production.
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Affiliation(s)
- Wankui Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, PR China
| | - Jingxiang Sun
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, PR China
| | - Haiyan Gao
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, PR China
| | - Yunhan Tang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, PR China
| | - Chao Wang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, PR China
| | - Yujia Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, PR China; Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 211816, PR China
| | - Wenming Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, PR China; Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 211816, PR China.
| | - Fengxue Xin
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, PR China; Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 211816, PR China.
| | - Min Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, PR China; Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 211816, PR China
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Chen HH, Liang MH, Ye ZW, Zhu YH, Jiang JG. Engineering the β-Carotene Metabolic Pathway of Microalgae Dunaliella To Confirm Its Carotenoid Synthesis Pattern in Comparison To Bacteria and Plants. Microbiol Spectr 2023; 11:e0436122. [PMID: 36719233 PMCID: PMC10100976 DOI: 10.1128/spectrum.04361-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 12/12/2022] [Indexed: 02/01/2023] Open
Abstract
Dunaliella salina is the most salt-tolerant eukaryote and has the highest β-carotene content, but its carotenoid synthesis pathway is still unclear, especially the synthesis of lycopene, the upstream product of β-carotene. In this study, DsGGPS, DsPSY, DsPDS, DsZISO, DsZDS, DsCRTISO, and DsLYCB genes were cloned from D. salina and expressed in Escherichia coli. A series of carotenoid engineering E. coli strains from phytoene to β-carotene were obtained. ZISO was first identified from Chlorophyta, while CRTISO was first isolated from algae. It was found that DsZISO and DsCRTISO were essential for isomerization of carotenoids in photosynthetic organisms and could not be replaced by photoisomerization, unlike some plants. DsZDS was found to have weak beta cyclization abilities, and DsLYCB was able to catalyze 7,7',9,9'-tetra-cis-lycopene to generate 7,7',9,9'-tetra-cis-β-carotene, which had not been reported before. A new carotenoid 7,7',9,9'-tetra-cis-β-carotene, the beta cyclization product of prolycopene, was discovered. Compared with the bacterial-derived carotenoid synthesis pathway, there is higher specificity and greater efficiency of the carotenoid synthesis pathway in algae. This research experimentally confirmed that the conversion of phytoene to lycopene in D. salina was similar to that of plants and different from bacteria and provided a new possibility for the metabolic engineering of β-carotene. IMPORTANCE The synthesis mode of all trans-lycopene in bacteria and plants is clear, but there are still doubts in microalgae. Dunaliella is the organism with the highest β-carotene content, and plant-type and bacterial-type enzyme genes have been found in its carotenoid metabolism pathway. In this study, the entire plant-type enzyme gene was completely cloned into Escherichia coli, and high-efficiency expression was obtained, which proved that carotenoid synthesis of algae is similar to that of plants. In bacteria, CRT can directly catalyze 4-step continuous dehydrogenation to produce all trans-lycopene. In plants, four enzymes (PDS, ZISO, ZDS, and CRTISO) are involved in this process. Although a carotenoid synthetase similar to that of bacteria has been found in algae, it does not play a major role. This research reveals the evolutionary relationship of carotenoid metabolism in bacteria, algae, and plants and is of methodologically innovative significance for molecular evolution research.
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Affiliation(s)
- Hao-Hong Chen
- School of Food Science and Engineering, South China University of Technology, Guangzhou, China
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | - Ming-Hua Liang
- School of Food Science and Engineering, South China University of Technology, Guangzhou, China
| | - Zhi-Wei Ye
- College of Food Science, South China Agricultural University, Guangzhou, China
| | - Yue-Hui Zhu
- Washington University School of Medicine, St. Louis, Missouri, USA
| | - Jian-Guo Jiang
- School of Food Science and Engineering, South China University of Technology, Guangzhou, China
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Summons RE, Welander PV, Gold DA. Lipid biomarkers: molecular tools for illuminating the history of microbial life. Nat Rev Microbiol 2022; 20:174-185. [PMID: 34635851 DOI: 10.1038/s41579-021-00636-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/07/2021] [Indexed: 11/09/2022]
Abstract
Fossilized lipids preserved in sedimentary rocks offer singular insights into the Earth's palaeobiology. These 'biomarkers' encode information pertaining to the oxygenation of the atmosphere and oceans, transitions in ocean plankton, the greening of continents, mass extinctions and climate change. Historically, biomarker interpretations relied on inventories of lipids present in extant microorganisms and counterparts in natural environments. However, progress has been impeded because only a small fraction of the Earth's microorganisms can be cultured, many environmentally significant microorganisms from the past no longer exist and there are gaping holes in knowledge concerning lipid biosynthesis. The revolution in genomics and bioinformatics has provided new tools to expand our understanding of lipid biomarkers, their biosynthetic pathways and distributions in nature. In this Review, we explore how preserved organic molecules provide a unique perspective on the history of the Earth's microbial life. We discuss how advances in molecular biology have helped elucidate biomarker origins and afforded more robust interpretations of fossil lipids and how the rock record provides vital calibration points for molecular clocks. Such studies are open to further exploitation with the expansion of sequenced microbial genomes in accessible databases.
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Affiliation(s)
- Roger E Summons
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA.
| | - Paula V Welander
- Department of Earth System Science, Stanford University, Stanford, CA, USA
| | - David A Gold
- Department of Earth & Planetary Sciences, University of California Davis, Davis, CA, USA
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Saini MK, Yoshida S, Sebastian A, Hara E, Tamaki H, Soulier NT, Albert I, Hanada S, Tank M, Bryant DA. Elioraea tepida, sp. nov., a Moderately Thermophilic Aerobic Anoxygenic Phototrophic Bacterium Isolated from the Mat Community of an Alkaline Siliceous Hot Spring in Yellowstone National Park, WY, USA. Microorganisms 2021; 10:80. [PMID: 35056529 PMCID: PMC8781829 DOI: 10.3390/microorganisms10010080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 12/24/2021] [Accepted: 12/30/2021] [Indexed: 11/17/2022] Open
Abstract
Strain MS-P2T was isolated from microbial mats associated with Mushroom Spring, an alkaline siliceous hot spring in Yellowstone National Park, WY, USA. The isolate grows chemoheterotrophically by oxygen-dependent respiration, and light stimulates photoheterotrophic growth under strictly oxic conditions. Strain MS-P2T synthesizes bacteriochlorophyll a and the carotenoid spirilloxanthin. However, photoautotrophic growth did not occur under oxic or anoxic conditions, suggesting that this strain should be classified as an aerobic anoxygenic phototrophic bacterium. Strain MS-P2T cells are motile, curved rods about 0.5 to 1.0 μm wide and 1.0 to 1.5 μm long. The optimum growth temperature is 45-50 °C, and the optimum pH for growth is circum-neutral (pH 7.0-7.5). Sequence analysis of the 16S rRNA gene revealed that strain MS-P2T is closely related to Elioraea species, members of the class Alphaproteobacteria, with a sequence identity of 96.58 to 98%. The genome of strain MS-P2T is a single circular DNA molecule of 3,367,643 bp with a mol% guanine-plus-cytosine content of 70.6%. Based on phylogenetic, physiological, biochemical, and genomic characteristics, we propose this bacteriochlorophyll a-containing isolate is a new species belonging to the genus Elioraea, with the suggested name Elioraeatepida. The type-strain is strain MS-P2T (= JCM33060T = ATCC TSD-174T).
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Affiliation(s)
- Mohit Kumar Saini
- Department of Biological Sciences, Tokyo Metropolitan University, Tokyo 192-0397, Japan; (M.K.S.); (S.Y.); (S.H.)
| | - Shohei Yoshida
- Department of Biological Sciences, Tokyo Metropolitan University, Tokyo 192-0397, Japan; (M.K.S.); (S.Y.); (S.H.)
| | - Aswathy Sebastian
- The Huck Institutes for the Life Sciences, The Pennsylvania State University, University Park, PA 16802, USA; (A.S.); (I.A.)
| | - Eri Hara
- Bioproduction Research Institute—National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1, Higashi, Tsukuba 305-8566, Japan; (E.H.); (H.T.)
| | - Hideyuki Tamaki
- Bioproduction Research Institute—National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1, Higashi, Tsukuba 305-8566, Japan; (E.H.); (H.T.)
| | - Nathan T. Soulier
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA;
| | - Istvan Albert
- The Huck Institutes for the Life Sciences, The Pennsylvania State University, University Park, PA 16802, USA; (A.S.); (I.A.)
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA;
| | - Satoshi Hanada
- Department of Biological Sciences, Tokyo Metropolitan University, Tokyo 192-0397, Japan; (M.K.S.); (S.Y.); (S.H.)
| | - Marcus Tank
- Department of Biological Sciences, Tokyo Metropolitan University, Tokyo 192-0397, Japan; (M.K.S.); (S.Y.); (S.H.)
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA;
- DSMZ-German Culture Collection of Microorganisms and Cell Cultures, GmbH Inhoffenstraße 7B, 38124 Braunschweig, Germany
| | - Donald A. Bryant
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA;
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6
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Sandmann G. Diversity and origin of carotenoid biosynthesis: its history of coevolution towards plant photosynthesis. THE NEW PHYTOLOGIST 2021; 232:479-493. [PMID: 34324713 DOI: 10.1111/nph.17655] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 07/06/2021] [Indexed: 06/13/2023]
Abstract
The development of photosynthesis was a highlight in the progression of bacteria. In addition to the photosystems with their structural proteins, the photosynthesis apparatus consists of different cofactors including essential carotenoids. Thus, the evolution of the carotenoid pathways in relation to the functionality of the resulting structures in photosynthesis is the focus of this review. Analysis of carotenoid pathway genes indicates early evolutionary roots in prokaryotes. The pathway complexity leading to a multitude of structures is a result of gene acquisition, including their functional modifications, emergence of novel genes and gene exchange between species. Along with the progression of photosynthesis, carotenoid pathways coevolved with photosynthesis according to their advancing functionality. Cyanobacteria, with their oxygenic photosynthesis, became a landmark for evolutionary events including carotenogenesis. Concurrent with endosymbiosis, the cyanobacterial carotenoid pathways were inherited into algal plastids. In the lineage leading to Chlorophyta and plants, carotenoids evolved to their prominent role in protection and regulation of light energy input as constituents of a highly efficient light-harvesting complex.
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Affiliation(s)
- Gerhard Sandmann
- Institute of Molecular Biosciences, Goethe-University Frankfurt/M, Max von Laue Str. 9, Frankfurt, D-60438, Germany
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7
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Sandmann G. Diversity and Evolution of Carotenoid Biosynthesis from Prokaryotes to Plants. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1261:79-94. [PMID: 33783732 DOI: 10.1007/978-981-15-7360-6_7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Carotenoids exist in pro- and eukaryotic organisms, but not in animals (with one exception). Their biosynthesis evolved from a common ancestor of Archaea and Bacteria and via the latter by endosymbiosis to algae and plants. The formation of carotenoids in fungi can be regarded as a lineage from the archaea. This review highlights the distribution and evolution of carotenogenic pathways in taxonomic groups of prokaryotes and eukaryotes with a special emphasis on the evolutionary aspects of prominent carotenogenic genes in relation to the assigned function of their corresponding enzymes. The latter aspect includes a focus on paralogs of gene families evolving novel functions and unrelated genes encoding enzymes with the same function.
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Affiliation(s)
- Gerhard Sandmann
- Biosynthesis Group, Molecular Biosciences, Goethe University, Frankfurt, Germany.
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8
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Jones AD, Boundy-Mills KL, Barla GF, Kumar S, Ubanwa B, Balan V. Microbial Lipid Alternatives to Plant Lipids. Methods Mol Biol 2019; 1995:1-32. [PMID: 31148119 DOI: 10.1007/978-1-4939-9484-7_1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Lipids are in high demand in food production, nutritional supplements, detergents, lubricants, and biofuels. Different oil seeds produced from plants are conventionally extracted to yield lipids. With increasing population and reduced availability of cultivable land, conventional methods of producing lipids alone will not satisfy increasing demand. Lipids produced using different microbial sources are considered as sustainable alternative to plant derived lipids. Various microorganisms belonging to the genera of algae, bacteria, yeast, fungi, or marine-derived microorganisms such as thraustochytrids possess the ability to accumulate lipids in their cells. A variety of microbial production technologies are being used to cultivate these organisms under specific conditions using agricultural residues as carbon source to be cost competitive with plant derived lipids. Microbial oils, also known as single cell oils, have many advantages when compared with plant derived lipids, such as shorter life cycle, less labor required, season and climate independence, no use of arable land and ease of scale-up. In this chapter we compare the lipids derived from plants and different microorganisms. We also highlight various analytical techniques that are being used to characterize the lipids produced in oleaginous organisms and their applications in various processes.
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Affiliation(s)
- A Daniel Jones
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, USA
- Department of Chemistry, Michigan State University, East Lansing, MI, USA
| | - Kyria L Boundy-Mills
- Phaff Yeast Culture Collection, Department of Food Science and Technology, University of California, Davis, Davis, CA, USA
| | - G Florin Barla
- Faculty of Food Engineering, University of Suceava, Suceava, Romania
- Tyton Biosciences, Danville, VA, USA
| | - Sandeep Kumar
- Department of Civil and Environmental Engineering, Old Dominion University, Norfolk, VA, USA
| | - Bryan Ubanwa
- Department of Engineering Technology, Biotechnology Program, College of Technology, University of Houston, Houston, TX, USA
| | - Venkatesh Balan
- Department of Engineering Technology, Biotechnology Program, College of Technology, University of Houston, Houston, TX, USA.
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Canniffe DP, Thweatt JL, Gomez Maqueo Chew A, Hunter CN, Bryant DA. A paralog of a bacteriochlorophyll biosynthesis enzyme catalyzes the formation of 1,2-dihydrocarotenoids in green sulfur bacteria. J Biol Chem 2018; 293:15233-15242. [PMID: 30126840 PMCID: PMC6166724 DOI: 10.1074/jbc.ra118.004672] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 08/17/2018] [Indexed: 12/03/2022] Open
Abstract
Chlorobaculum tepidum, a green sulfur bacterium, utilizes chlorobactene as its major carotenoid, and this organism also accumulates a reduced form of this monocyclic pigment, 1′,2′-dihydrochlorobactene. The protein catalyzing this reduction is the last unidentified enzyme in the biosynthetic pathways for all of the green sulfur bacterial pigments used for photosynthesis. The genome of C. tepidum contains two paralogous genes encoding members of the FixC family of flavoproteins: bchP, which has been shown to encode an enzyme of bacteriochlorophyll biosynthesis; and bchO, for which a function has not been assigned. Here we demonstrate that a bchO mutant is unable to synthesize 1′,2′-dihydrochlorobactene, and when bchO is heterologously expressed in a neurosporene-producing mutant of the purple bacterium, Rhodobacter sphaeroides, the encoded protein is able to catalyze the formation of 1,2-dihydroneurosporene, the major carotenoid of the only other organism reported to synthesize 1,2-dihydrocarotenoids, Blastochloris viridis. Identification of this enzyme completes the pathways for the synthesis of photosynthetic pigments in Chlorobiaceae, and accordingly and consistent with its role in carotenoid biosynthesis, we propose to rename the gene cruI. Notably, the absence of cruI in B. viridis indicates that a second 1,2-carotenoid reductase, which is structurally unrelated to CruI (BchO), must exist in nature. The evolution of this carotenoid reductase in green sulfur bacteria is discussed herein.
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Affiliation(s)
- Daniel P Canniffe
- From the Department of Molecular Biology & Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom, .,the Department of Biochemistry & Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, and
| | - Jennifer L Thweatt
- the Department of Biochemistry & Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, and
| | - Aline Gomez Maqueo Chew
- the Department of Biochemistry & Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, and
| | - C Neil Hunter
- From the Department of Molecular Biology & Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom
| | - Donald A Bryant
- the Department of Biochemistry & Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, and .,the Department of Chemistry & Biochemistry, Montana State University, Bozeman, Montana 59717
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10
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Engleder M, Pichler H. On the current role of hydratases in biocatalysis. Appl Microbiol Biotechnol 2018; 102:5841-5858. [PMID: 29785499 PMCID: PMC6013536 DOI: 10.1007/s00253-018-9065-7] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 04/27/2018] [Accepted: 04/27/2018] [Indexed: 11/06/2022]
Abstract
Water addition to carbon-carbon double bonds provides access to value-added products from inexpensive organic feedstock. This interesting but relatively little-studied reaction is catalysed by hydratases in a highly regio- and enantiospecific fashion with excellent atom economy. Considering that asymmetric hydration of (non-activated) carbon-carbon double bonds is virtually impossible with current organic chemistry, enzymatic hydration reactions are highly attractive for industrial applications. Hydratases have been known for several decades but their biocatalytic potential has only been explored over the past 15 years. As a result, a considerable amount of information on this enzyme group has become available, enabling their development for practical applications. This review focuses on hydratases catalysing water addition to non-activated carbon-carbon double bonds, and examines hydratases from a biochemical, structural and mechanistic angle. Current challenges and opportunities in hydration biocatalysis are discussed, and, ultimately, their potential for organic synthesis is highlighted.
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Affiliation(s)
- Matthias Engleder
- Austrian Centre of Industrial Biotechnology (acib), Petersgasse 14, 8010, Graz, Austria
- Institute of Molecular Biotechnology, Graz University of Technology, NAWI Graz, BioTechMed Graz, Petersgasse 8010, Graz, Austria
| | - Harald Pichler
- Austrian Centre of Industrial Biotechnology (acib), Petersgasse 14, 8010, Graz, Austria.
- Institute of Molecular Biotechnology, Graz University of Technology, NAWI Graz, BioTechMed Graz, Petersgasse 8010, Graz, Austria.
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11
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Adadi P, Barakova NV, Krivoshapkina EF. Selected Methods of Extracting Carotenoids, Characterization, and Health Concerns: A Review. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:5925-5947. [PMID: 29851485 DOI: 10.1021/acs.jafc.8b01407] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Carotenoids are the most powerful nutrients (medicine) on earth due to their potent antioxidant properties. The ability of these tetraterpenoids in obviating human chronic ailments like cancer, cardiovascular disease, osteoporosis, and diabetes has drawn public attention toward these novel compounds. Conventionally, carotenoids have been extracted from plant materials and agro-industrial byproduct using different solvents, but these procedures result in contaminating the target compound (carotenoids) with extraction solvents. Furthermore, some utilized solvents are not safe and hence are harmful to the environment. This has attracted criticism from consumers, ecologists, environmentalists, and public health workers. However, there is clear consumer preference for carotenoids from natural origin without traces of extracting solvent. Therefore, this review seeks to discuss methods for higher recovery of pure carotenoids without contamination from a solvent. Methods such as enzyme-based extraction, supercritical fluid extraction, microwave-assisted extraction, Soxhlet extraction, ultrasonic extraction, and postextraction treatment (saponification) are discussed. Merits and demerits of these methods along with health concerns during intake of carotenoids were also considered.
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Affiliation(s)
- Parise Adadi
- ITMO University , Lomonosova Street 9 , 191002 , St. Petersburg , Russia Federation
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12
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Posth NR, Bristow LA, Cox RP, Habicht KS, Danza F, Tonolla M, Frigaard NU, Canfield DE. Carbon isotope fractionation by anoxygenic phototrophic bacteria in euxinic Lake Cadagno. GEOBIOLOGY 2017; 15:798-816. [PMID: 28866873 DOI: 10.1111/gbi.12254] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Accepted: 07/14/2017] [Indexed: 06/07/2023]
Abstract
Anoxygenic phototrophic bacteria utilize ancient metabolic pathways to link sulfur and iron metabolism to the reduction of CO2 . In meromictic Lake Cadagno, Switzerland, both purple sulfur (PSB) and green sulfur anoxygenic phototrophic bacteria (GSB) dominate the chemocline community and drive the sulfur cycle. PSB and GSB fix carbon utilizing different enzymatic pathways and these fractionate C-isotopes to different extents. Here, these differences in C-isotope fractionation are used to constrain the relative input of various anoxygenic phototrophs to the bulk community C-isotope signal in the chemocline. We sought to determine whether a distinct isotopic signature of GSB and PSB in the chemocline persists in the settling fraction and in the sediment. To answer these questions, we also sought investigated C-isotope fractionation in the water column, settling material, and sediment of Lake Cadagno, compared these values to C-isotope fractionation of isolated anoxygenic phototroph cultures, and took a mass balance approach to investigate relative contributions to the bulk fractionation signature. We found a large C-isotope fractionation between dissolved inorganic carbon (DIC) and particulate organic carbon (POC) in the Lake Cadagno chemocline. This large fractionation between the DIC and POC was also found in culture experiments carried out with anoxygenic phototrophic bacteria isolated from the lake. In the Lake Cadagno chemocline, anoxygenic phototrophic bacteria controlled the bulk C-isotope fractionation, but the influence of GSB and PSB differed with season. Furthermore, the contribution of PSB and GSB to bulk C-isotope fractionation in the chemocline could be traced in the settling fraction and in the sediment. Taken together with other studies, such as lipid biomarker analyzes and investigations of other stratified lakes, these results offer a firmer understanding of diagenetic influences on bacterial biomass.
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Affiliation(s)
- N R Posth
- Department of Biology, Nordic Centre for Earth Evolution (Nordcee), University of Southern Denmark, Odense M, Denmark
| | - L A Bristow
- Department of Biology, Nordic Centre for Earth Evolution (Nordcee), University of Southern Denmark, Odense M, Denmark
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - R P Cox
- Department of Biology, Nordic Centre for Earth Evolution (Nordcee), University of Southern Denmark, Odense M, Denmark
| | - K S Habicht
- Department of Biology, Nordic Centre for Earth Evolution (Nordcee), University of Southern Denmark, Odense M, Denmark
- Unisense A/S, Aarhus N, Denmark
| | - F Danza
- Laboratory of Applied Microbiology, University of Applied Sciences Southern Switzerland, Bellinzona, Switzerland
- Department of Botany and Plant Biology, Microbiology Unit, University of Geneva, Geneva, Switzerland
| | - M Tonolla
- Laboratory of Applied Microbiology, University of Applied Sciences Southern Switzerland, Bellinzona, Switzerland
- Department of Botany and Plant Biology, Microbiology Unit, University of Geneva, Geneva, Switzerland
- Alpine Biology Center Foundation, Bellinzona, Switzerland
| | - N-U Frigaard
- Department of Biology, Section for Marine Biology, University of Copenhagen, Helsingør, Denmark
| | - D E Canfield
- Department of Biology, Nordic Centre for Earth Evolution (Nordcee), University of Southern Denmark, Odense M, Denmark
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Complementation of Cobalamin Auxotrophy in Synechococcus sp. Strain PCC 7002 and Validation of a Putative Cobalamin Riboswitch In Vivo. J Bacteriol 2016; 198:2743-52. [PMID: 27457714 DOI: 10.1128/jb.00475-16] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 07/19/2016] [Indexed: 01/12/2023] Open
Abstract
UNLABELLED The euryhaline cyanobacterium Synechococcus sp. strain PCC 7002 has an obligate requirement for exogenous vitamin B12 (cobalamin), but little is known about the roles of this compound in cyanobacteria. Bioinformatic analyses suggest that only the terminal enzyme in methionine biosynthesis, methionine synthase, requires cobalamin as a coenzyme in Synechococcus sp. strain PCC 7002. Methionine synthase (MetH) catalyzes the transfer of a methyl group from N(5)-methyl-5,6,7,8-tetrahydrofolate to l-homocysteine during l-methionine synthesis and uses methylcobalamin as an intermediate methyl donor. Numerous bacteria and plants alternatively employ a cobalamin-independent methionine synthase isozyme, MetE, that catalyzes the same methyl transfer reaction as MetH but uses N(5)-methyl-5,6,7,8-tetrahydrofolate directly as the methyl donor. The cobalamin auxotrophy of Synechococcus sp. strain PCC 7002 was complemented by using the metE gene from the closely related cyanobacterium Synechococcus sp. strain PCC 73109, which possesses genes for both methionine synthases. This result suggests that methionine biosynthesis is probably the sole use of cobalamin in Synechococcus sp. strain PCC 7002. Furthermore, a cobalamin-repressible gene expression system was developed in Synechococcus sp. strain PCC 7002 that was used to validate the presence of a cobalamin riboswitch in the promoter region of metE from Synechococcus sp. strain PCC 73109. This riboswitch acts as a cobalamin-dependent transcriptional attenuator for metE in that organism. IMPORTANCE Synechococcus sp. strain PCC 7002 is a cobalamin auxotroph because, like eukaryotic marine algae, it uses a cobalamin-dependent methionine synthase (MetH) for the final step of l-methionine biosynthesis but cannot synthesize cobalamin de novo Heterologous expression of metE, encoding cobalamin-independent methionine synthase, from Synechococcus sp. strain PCC 73109, relieved this auxotrophy and enabled the construction of a truly autotrophic Synechococcus sp. strain PCC 7002 more suitable for large-scale industrial applications. Characterization of a cobalamin riboswitch expands the genetic toolbox for Synechococcus sp. strain PCC 7002 by providing a cobalamin-repressible expression system.
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A single desaturase gene from red yeast Sporidiobolus pararoseus is responsible for both four- and five-step dehydrogenation of phytoene. Gene 2016; 590:169-76. [DOI: 10.1016/j.gene.2016.06.042] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 06/07/2016] [Accepted: 06/20/2016] [Indexed: 01/28/2023]
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Agapov AA, Kulbachinskiy AV. Mechanisms of Stress Resistance and Gene Regulation in the Radioresistant Bacterium Deinococcus radiodurans. BIOCHEMISTRY (MOSCOW) 2016; 80:1201-16. [PMID: 26567564 DOI: 10.1134/s0006297915100016] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The bacterium Deinococcus radiodurans reveals extraordinary resistance to ionizing radiation, oxidative stress, desiccation, and other damaging conditions. In this review, we consider the main molecular mechanisms underlying such resistance, including the action of specific DNA repair and antioxidation systems, and transcription regulation during the anti-stress response.
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Affiliation(s)
- A A Agapov
- Institute of Molecular Genetics, Russian Academy of Sciences, Moscow, 123182, Russia.
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16
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In situ high-resolution structure of the baseplate antenna complex in Chlorobaculum tepidum. Nat Commun 2016; 7:12454. [PMID: 27534696 PMCID: PMC4992139 DOI: 10.1038/ncomms12454] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 07/05/2016] [Indexed: 01/01/2023] Open
Abstract
Photosynthetic antenna systems enable organisms harvesting light and transfer the energy to the photosynthetic reaction centre, where the conversion to chemical energy takes place. One of the most complex antenna systems, the chlorosome, found in the photosynthetic green sulfur bacterium Chlorobaculum (Cba.) tepidum contains a baseplate, which is a scaffolding super-structure, formed by the protein CsmA and bacteriochlorophyll a. Here we present the first high-resolution structure of the CsmA baseplate using intact fully functional, light-harvesting organelles from Cba. tepidum, following a hybrid approach combining five complementary methods: solid-state NMR spectroscopy, cryo-electron microscopy, isotropic and anisotropic circular dichroism and linear dichroism. The structure calculation was facilitated through development of new software, GASyCS for efficient geometry optimization of highly symmetric oligomeric structures. We show that the baseplate is composed of rods of repeated dimers of the strongly amphipathic CsmA with pigments sandwiched within the dimer at the hydrophobic side of the helix. The chlorosome of the photosynthetic bacterium C. tepidum harvests light and transfers the energy to the photosynthetic reaction centre. Here the authors determine the structure of the baseplate, a scaffolding super-structure, to show that the baseplate consists of rods of repeated CsmA dimers containing pigment molecules.
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Abstract
A substantial proportion of the dazzling diversity of colors displayed by living organisms throughout the tree of life is determined by the presence of carotenoids, which most often provide distinctive yellow, orange and red hues. These metabolites play fundamental roles in nature that extend far beyond their importance as pigments. In photosynthetic lineages, carotenoids are essential to sustain life, since they have been exploited to maximize light harvesting and protect the photosynthetic machinery from photooxidative stress. Consequently, photosynthetic organisms have evolved several mechanisms that adjust the carotenoid metabolism to efficiently cope with constantly fluctuating light environments. This chapter will focus on the current knowledge concerning the regulation of the carotenoid biosynthetic pathway in leaves, which are the primary photosynthetic organs of most land plants.
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Frigaard NU. Biotechnology of Anoxygenic Phototrophic Bacteria. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2016; 156:139-154. [DOI: 10.1007/10_2015_5006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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19
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Mizoguchi T, Harada J, Yamamoto K, Tamiaki H. Inactivation of bciD and bchU genes in the green sulfur bacterium Chlorobaculum limnaeum and alteration of photosynthetic pigments in the resultant mutants. J Photochem Photobiol A Chem 2015. [DOI: 10.1016/j.jphotochem.2015.06.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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20
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Meléndez-Martínez AJ, Mapelli-Brahm P, Benítez-González A, Stinco CM. A comprehensive review on the colorless carotenoids phytoene and phytofluene. Arch Biochem Biophys 2015; 572:188-200. [DOI: 10.1016/j.abb.2015.01.003] [Citation(s) in RCA: 119] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Revised: 12/30/2014] [Accepted: 01/04/2015] [Indexed: 12/22/2022]
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21
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Hiseni A, Arends IWCE, Otten LG. New Cofactor-Independent Hydration Biocatalysts: Structural, Biochemical, and Biocatalytic Characteristics of Carotenoid and Oleate Hydratases. ChemCatChem 2014. [DOI: 10.1002/cctc.201402511] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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22
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Wang C, Kim JH, Kim SW. Synthetic biology and metabolic engineering for marine carotenoids: new opportunities and future prospects. Mar Drugs 2014; 12:4810-32. [PMID: 25233369 PMCID: PMC4178492 DOI: 10.3390/md12094810] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2014] [Revised: 08/29/2014] [Accepted: 09/01/2014] [Indexed: 11/17/2022] Open
Abstract
Carotenoids are a class of diverse pigments with important biological roles such as light capture and antioxidative activities. Many novel carotenoids have been isolated from marine organisms to date and have shown various utilizations as nutraceuticals and pharmaceuticals. In this review, we summarize the pathways and enzymes of carotenoid synthesis and discuss various modifications of marine carotenoids. The advances in metabolic engineering and synthetic biology for carotenoid production are also reviewed, in hopes that this review will promote the exploration of marine carotenoid for their utilizations.
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Affiliation(s)
- Chonglong Wang
- Division of Applied Life Science (BK21 Plus), PMBBRC, Gyeongsang National University, Jinju 660-701, Korea.
| | - Jung-Hun Kim
- Division of Applied Life Science (BK21 Plus), PMBBRC, Gyeongsang National University, Jinju 660-701, Korea.
| | - Seon-Won Kim
- Division of Applied Life Science (BK21 Plus), PMBBRC, Gyeongsang National University, Jinju 660-701, Korea.
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23
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Kihara S, Hartzler DA, Savikhin S. Oxygen concentration inside a functioning photosynthetic cell. Biophys J 2014; 106:1882-9. [PMID: 24806920 PMCID: PMC4017319 DOI: 10.1016/j.bpj.2014.03.031] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Revised: 02/13/2014] [Accepted: 03/12/2014] [Indexed: 11/23/2022] Open
Abstract
The excess oxygen concentration in the photosynthetic membranes of functioning oxygenic photosynthetic cells was estimated using classical diffusion theory combined with experimental data on oxygen production rates of cyanobacterial cells. The excess oxygen concentration within the plesiomorphic cyanobacterium Gloeobactor violaceus is only 0.025 μM, or four orders of magnitude lower than the oxygen concentration in air-saturated water. Such a low concentration suggests that the first oxygenic photosynthetic bacteria in solitary form could have evolved ∼2.8 billion years ago without special mechanisms to protect them against reactive oxygen species. These mechanisms instead could have been developed during the following ∼500 million years while the oxygen level in the Earth's atmosphere was slowly rising. Excess oxygen concentrations within individual cells of the apomorphic cyanobacteria Synechocystis and Synechococcus are 0.064 and 0.25 μM, respectively. These numbers suggest that intramembrane and intracellular proteins in isolated oxygenic photosynthetic cells are not subjected to excessively high oxygen levels. The situation is different for closely packed colonies of photosynthetic cells. Calculations show that the excess concentration within colonies that are ∼40 μm or larger in diameter can be comparable to the oxygen concentration in air-saturated water, suggesting that species forming colonies require protection against reactive oxygen species even in the absence of oxygen in the surrounding atmosphere.
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Affiliation(s)
- Shigeharu Kihara
- Department of Physics, Purdue University, West Lafayette, Indiana
| | | | - Sergei Savikhin
- Department of Physics, Purdue University, West Lafayette, Indiana.
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24
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Guo W, Tang H, Zhang L. Lycopene cyclase and phytoene synthase activities in the marine yeast Rhodosporidium diobovatum are encoded by a single gene crtYB. J Basic Microbiol 2014; 54:1053-61. [PMID: 24677129 DOI: 10.1002/jobm.201300920] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Accepted: 01/26/2014] [Indexed: 11/05/2022]
Abstract
crtYB, encoding lycopene cyclase and phytoene synthase was cloned from Rhodosporidium diobovatum ATCC 2527 by rapid amplification of cDNA ends method. The full-length cDNA of crtYB is 2, 330 bp and contains eight introns. The gene products is a 594 amino acids, with a predicted molecular mass of 65.63 kDa and a pI of 6.73. The N-terminus of the protein contains six transmembrane regions, which has been characterized as a lycopene beta-cyclase. The C-terminal half has squalene and phytoene synthase signatures that identified as phytoene synthetase. By heterologous complementary detection of this gene in E. coli and HPLC analysis, the regions responsible for phytoene synthesis and lycopene cyclization were localized within the protein.
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Affiliation(s)
- Wenjing Guo
- Key Discipline of Biological Engineering of Hebei Province, College of Life Sciences, Hebei University, Baoding, China; Key Laboratory of Microbial Diversity Research and Application of Hebei Province, College of Life Sciences, Hebei University, Baoding, China
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25
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Affiliation(s)
| | - Salim Al-Babili
- BESE Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
| | - Eleanore T. Wurtzel
- The Graduate School and University Center, The City University of New York, New York, New York, USA
- Department of Biological Sciences, Lehman College, The City University of New York, Bronx, New York, USA
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26
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Kirk KE, Hoffman JA, Smith KA, Strahan BL, Failor KC, Krebs JE, Gale AN, Do TD, Sontag TC, Batties AM, Mistiszyn K, Newman JD. Chryseobacterium angstadtii sp. nov., isolated from a newt tank. Int J Syst Evol Microbiol 2013; 63:4777-4783. [PMID: 23996834 DOI: 10.1099/ijs.0.054478-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
As part of an undergraduate microbiology course, a yellow-orange-pigmented, Gram-staining negative, rod-shaped, non-motile bacterial strain was isolated from a glass tank housing several red-spotted newts (Notophthalmus viridescens). The sequence of the 16S rRNA gene of this strain, designated KM(T), was 97.4-98.0 % similar to those of the type strains of Chryseobacterium luteum, C. shigense and C. vrystaatense, while the similarity levels for protein-coding genes were less than 94.7 % for rpoB, less than 92.1 % for groEL and less than 87.1 % for gyrB. These values are lower than for many other established distinct species. Polyphasic characterization and comparison to these relatives revealed that strain KM(T) was similar to other Chryseobacterium strains in that it contained MK-6 as its major respiratory quinone and phosphatidylethanolamine as the most abundant polar lipid, produced flexirubin-type pigments, oxidase and catalase and primarily contained the fatty acids iso-C15 : 0, iso-C17 : 1ω9c, iso-C17 : 0 3-OH and summed feature 3 (comprising C16 : 1ω6c and/or C16 : 1ω7c). Based on the results of this study, strain KM(T) represents a novel species, for which the name Chryseobacterium angstadtii sp. nov. is proposed. The type strain is KM(T) ( = ATCC BAA-2160(T) = NRRL B-59516(T) = KCTC 23297(T)).
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Affiliation(s)
- Karen E Kirk
- Biology Department, Lycoming College, Williamsport, PA 17701, USA
| | | | | | | | - Kevin C Failor
- Biology Department, Lycoming College, Williamsport, PA 17701, USA
| | - Jordan E Krebs
- Biology Department, Lycoming College, Williamsport, PA 17701, USA
| | - Andrew N Gale
- Biology Department, Lycoming College, Williamsport, PA 17701, USA
| | - Tri D Do
- Biology Department, Lycoming College, Williamsport, PA 17701, USA
| | - Thomas C Sontag
- Biology Department, Lycoming College, Williamsport, PA 17701, USA
| | | | | | - Jeffrey D Newman
- Biology Department, Lycoming College, Williamsport, PA 17701, USA
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Adams PG, Cadby AJ, Robinson B, Tsukatani Y, Tank M, Wen J, Blankenship RE, Bryant DA, Hunter CN. Comparison of the physical characteristics of chlorosomes from three different phyla of green phototrophic bacteria. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013; 1827:1235-44. [PMID: 23867748 DOI: 10.1016/j.bbabio.2013.07.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Revised: 07/05/2013] [Accepted: 07/08/2013] [Indexed: 11/18/2022]
Abstract
Chlorosomes, the major antenna complexes in green sulphur bacteria, filamentous anoxygenic phototrophs, and phototrophic acidobacteria, are attached to the cytoplasmic side of the inner cell membrane and contain thousands of bacteriochlorophyll (BChl) molecules that harvest light and channel the energy to membrane-bound reaction centres. Chlorosomes from phototrophs representing three different phyla, Chloroflexus (Cfx.) aurantiacus, Chlorobaculum (Cba.) tepidum and the newly discovered "Candidatus (Ca.) Chloracidobacterium (Cab.) thermophilum" were analysed using PeakForce Tapping atomic force microscopy (PFT-AFM). Gentle PFT-AFM imaging in buffered solutions that maintained the chlorosomes in a near-native state revealed ellipsoids of variable size, with surface bumps and undulations that differ between individual chlorosomes. Cba. tepidum chlorosomes were the largest (133×57×36nm; 141,000nm(3) volume), compared with chlorosomes from Cfx. aurantiacus (120×44×30nm; 84,000nm(3)) and Ca. Cab. thermophilum (99×40×31nm; 65,000nm(3)). Reflecting the contributions of thousands of pigment-pigment stacking interactions to the stability of these supramolecular assemblies, analysis by nanomechanical mapping shows that chlorosomes are highly stable and that their integrity is disrupted only by very strong forces of 1000-2000pN. AFM topographs of Ca. Cab. thermophilum chlorosomes that had retained their attachment to the cytoplasmic membrane showed that this membrane dynamically changes shape and is composed of protrusions of up to 30nm wide and 6nm above the mica support, possibly representing different protein domains. Spectral imaging revealed significant heterogeneity in the fluorescence emission of individual chlorosomes, likely reflecting the variations in BChl c homolog composition and internal arrangements of the stacked BChls within each chlorosome.
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Affiliation(s)
- Peter G Adams
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, UK
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28
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Orf GS, Tank M, Vogl K, Niedzwiedzki DM, Bryant DA, Blankenship RE. Spectroscopic insights into the decreased efficiency of chlorosomes containing bacteriochlorophyll f. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013; 1827:493-501. [DOI: 10.1016/j.bbabio.2013.01.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Revised: 01/08/2013] [Accepted: 01/15/2013] [Indexed: 11/24/2022]
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29
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Vogl K, Tank M, Orf GS, Blankenship RE, Bryant DA. Bacteriochlorophyll f: properties of chlorosomes containing the "forbidden chlorophyll". Front Microbiol 2012; 3:298. [PMID: 22908012 PMCID: PMC3415949 DOI: 10.3389/fmicb.2012.00298] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Accepted: 07/25/2012] [Indexed: 11/13/2022] Open
Abstract
The chlorosomes of green sulfur bacteria (GSB) are mainly assembled from one of three types of bacteriochlorophylls (BChls), BChls c, d, and e. By analogy to the relationship between BChl c and BChl d (20-desmethyl-BChl c), a fourth type of BChl, BChl f (20-desmethyl-BChl e), should exist but has not yet been observed in nature. The bchU gene (bacteriochlorophyllide C-20 methyltransferase) of the brown-colored green sulfur bacterium Chlorobaculum limnaeum was inactivated by conjugative transfer from Eshcerichia coli and homologous recombination of a suicide plasmid carrying a portion of the bchU. The resulting bchU mutant was greenish brown in color and synthesized BChl f(F). The chlorosomes of the bchU mutant had similar size and polypeptide composition as those of the wild type (WT), but the Q(y) absorption band of the BChl f aggregates was blue-shifted 16 nm (705 nm vs. 721 nm for the WT). Fluorescence spectroscopy showed that energy transfer to the baseplate was much less efficient in chlorosomes containing BChl f than in WT chlorosomes containing BChl e. When cells were grown at high irradiance with tungsten or fluorescent light, the WT and bchU mutant had identical growth rates. However, the WT grew about 40% faster than the bchU mutant at low irradiance (10 μmol photons m(-2) s(-1)). Less efficient energy transfer from BChl f aggregates to BChl a in the baseplate, the much slower growth of the strain producing BChl f relative to the WT, and competition from other phototrophs, may explain why BChl f is not observed naturally.
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Affiliation(s)
- Kajetan Vogl
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park PA, USA
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30
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Enhanced production of astaxanthin in Paracoccus sp. strain N-81106 by using random mutagenesis and genetic engineering. Biochem Eng J 2012. [DOI: 10.1016/j.bej.2012.03.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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31
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Liu Z, Frigaard NU, Vogl K, Iino T, Ohkuma M, Overmann J, Bryant DA. Complete Genome of Ignavibacterium album, a Metabolically Versatile, Flagellated, Facultative Anaerobe from the Phylum Chlorobi. Front Microbiol 2012; 3:185. [PMID: 22661972 PMCID: PMC3362086 DOI: 10.3389/fmicb.2012.00185] [Citation(s) in RCA: 101] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2012] [Accepted: 05/04/2012] [Indexed: 11/13/2022] Open
Abstract
Prior to the recent discovery of Ignavibacterium album (I. album), anaerobic photoautotrophic green sulfur bacteria (GSB) were the only members of the bacterial phylum Chlorobi that had been grown axenically. In contrast to GSB, sequence analysis of the 3.7-Mbp genome of I. album shows that this recently described member of the phylum Chlorobi is a chemoheterotroph with a versatile metabolism. I. album lacks genes for photosynthesis and sulfur oxidation but has a full set of genes for flagella and chemotaxis. The occurrence of genes for multiple electron transfer complexes suggests that I. album is capable of organoheterotrophy under both oxic and anoxic conditions. The occurrence of genes encoding enzymes for CO(2) fixation as well as other enzymes of the reductive TCA cycle suggests that mixotrophy may be possible under certain growth conditions. However, known biosynthetic pathways for several amino acids are incomplete; this suggests that I. album is dependent upon on exogenous sources of these metabolites or employs novel biosynthetic pathways. Comparisons of I. album and other members of the phylum Chlorobi suggest that the physiology of the ancestors of this phylum might have been quite different from that of modern GSB.
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Affiliation(s)
- Zhenfeng Liu
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University University Park, PA, USA
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Abstract
Purple sulfur bacteria (PSB) mainly occur in anoxic aquatic and benthic environments, where they play important roles in cycling carbon and sulfur. Many PSB characteristically produce the unique keto-carotenoid, okenone, which is important not only for its light absorption and photoprotection properties but also because of its diagenesis product, okenane, which is a biomarker for ancient sediments derived from anoxic environments. The specific methylation pattern of the χ-ring of okenane is unlikely to be formed by diagenetic processes and should therefore reflect an enzymatic activity from okenone biosynthesis. This study describes two enzymes that produce the χ-ring of okenone, the only structural element of okenone preserved in okenane. Genes encoding enzymes of carotenogenesis were identified in the draft genome sequence of an okenone-producing PSB, Thiodictyon sp. strain CAD16. Two divergently transcribed genes encoded a CrtY-type lycopene cyclase and a CrtU/CruE-type γ-carotene desaturase/methyltransferase. Expression of crtY in Escherichia coli showed that this gene encoded a lycopene cyclase that produced γ-carotene as the only product. Although the sequence of the γ-carotene desaturase/methyltransferase was more similar to CrtU sequences of green sulfur bacteria than to CruE sequences of cyanobacteria, expression of the crtU gene in Chlorobaculum tepidum showed that the enzyme produced carotenoids with χ-rings rather than φ-rings. Phylogenetic analysis of the carotene desaturase/methyltransferases revealed that enzymes capable of converting β-rings to χ-rings have independently evolved at least two times. These results indicate that it probably will not be possible to deduce the activity of carotene desaturase/methyltransferases solely from sequence data.
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Affiliation(s)
- K Vogl
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, USA
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Garcia Costas AM, Tsukatani Y, Rijpstra WIC, Schouten S, Welander PV, Summons RE, Bryant DA. Identification of the bacteriochlorophylls, carotenoids, quinones, lipids, and hopanoids of "Candidatus Chloracidobacterium thermophilum". J Bacteriol 2012; 194:1158-68. [PMID: 22210764 PMCID: PMC3294765 DOI: 10.1128/jb.06421-11] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2011] [Accepted: 12/19/2011] [Indexed: 11/20/2022] Open
Abstract
"Candidatus Chloracidobacterium thermophilum" is a recently discovered chlorophototroph from the bacterial phylum Acidobacteria, which synthesizes bacteriochlorophyll (BChl) c and chlorosomes like members of the green sulfur bacteria (GSB) and the green filamentous anoxygenic phototrophs (FAPs). The pigments (BChl c homologs and carotenoids), quinones, lipids, and hopanoids of cells and chlorosomes of this new chlorophototroph were characterized in this study. "Ca. Chloracidobacterium thermophilum" methylates its antenna BChls at the C-8(2) and C-12(1) positions like GSB, but these BChls were esterified with a variety of isoprenoid and straight-chain alkyl alcohols as in FAPs. Unlike the chlorosomes of other green bacteria, "Ca. Chloracidobacterium thermophilum" chlorosomes contained two major xanthophyll carotenoids, echinenone and canthaxanthin. These carotenoids may confer enhanced protection against reactive oxygen species and could represent a specific adaptation to the highly oxic natural environment in which "Ca. Chloracidobacterium thermophilum" occurs. Dihydrogenated menaquinone-8 [menaquinone-8(H(2))], which probably acts as a quencher of energy transfer under oxic conditions, was an abundant component of both cells and chlorosomes of "Ca. Chloracidobacterium thermophilum." The betaine lipid diacylglycerylhydroxymethyl-N,N,N-trimethyl-β-alanine, esterified with 13-methyl-tetradecanoic (isopentadecanoic) acid, was a prominent polar lipid in the membranes of both "Ca. Chloracidobacterium thermophilum" cells and chlorosomes. This lipid may represent a specific adaptive response to chronic phosphorus limitation in the mats. Finally, three hopanoids, diploptene, bacteriohopanetetrol, and bacteriohopanetetrol cyclitol ether, which may help to stabilize membranes during diel shifts in pH and other physicochemical conditions in the mats, were detected in the membranes of "Ca. Chloracidobacterium thermophilum."
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Affiliation(s)
- Amaya M. Garcia Costas
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Yusuke Tsukatani
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - W. Irene C. Rijpstra
- NIOZ Royal Netherlands Institute for Sea Research, Department of Marine Organic Biogeochemistry, Den Burg, The Netherlands
| | - Stefan Schouten
- NIOZ Royal Netherlands Institute for Sea Research, Department of Marine Organic Biogeochemistry, Den Burg, The Netherlands
| | - Paula V. Welander
- Department of Earth, Atmospheric and Planetary Science, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Roger E. Summons
- Department of Earth, Atmospheric and Planetary Science, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Donald A. Bryant
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana, USA
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Cao L, Bryant DA, Schepmoes AA, Vogl K, Smith RD, Lipton MS, Callister SJ. Comparison of Chloroflexus aurantiacus strain J-10-fl proteomes of cells grown chemoheterotrophically and photoheterotrophically. PHOTOSYNTHESIS RESEARCH 2012; 110:153-168. [PMID: 22249883 DOI: 10.1007/s11120-011-9711-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Accepted: 11/25/2011] [Indexed: 05/31/2023]
Abstract
Chloroflexus aurantiacus J-10-fl is a thermophilic green bacterium, a filamentous anoxygenic phototroph, and the model organism of the phylum Chloroflexi. We applied high-throughput, liquid chromatography-mass spectrometry in a global quantitative proteomics investigation of C. aurantiacus cells grown under oxic (chemoorganoheterotrophically) and anoxic (photoorganoheterotrophically) redox states. Our global analysis identified 13,524 high-confidence peptides that matched to 1,286 annotated proteins, 242 of which were either uniquely identified or significantly increased in abundance under photoheterotrophic culture condition. Fifty-four of the 242 proteins are previously characterized photosynthesis-related proteins, including chlorosome proteins, proteins involved in the bacteriochlorophyll biosynthesis, 3-hydroxypropionate (3-OHP) CO(2) fixation pathway, and components of electron transport chains. The remaining 188 proteins have not previously been reported. Of these, five proteins were found to be encoded by genes from a novel operon and observed only in photoheterotrophically grown cells. These proteins candidates may prove useful in further deciphering the phototrophic physiology of C. aurantiacus and other filamentous anoxygenic phototrophs.
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Affiliation(s)
- Li Cao
- Biological Separations and Mass Spectrometry, Pacific Northwest National Laboratory, Richland, WA 99352, USA
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Comparative and Functional Genomics of Anoxygenic Green Bacteria from the Taxa Chlorobi, Chloroflexi, and Acidobacteria. FUNCTIONAL GENOMICS AND EVOLUTION OF PHOTOSYNTHETIC SYSTEMS 2012. [DOI: 10.1007/978-94-007-1533-2_3] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Vogl K, Bryant DA. Elucidation of the biosynthetic pathway for Okenone in Thiodictyon sp. CAD16 leads to the discovery of two novel carotene ketolases. J Biol Chem 2011; 286:38521-38532. [PMID: 21921032 PMCID: PMC3207450 DOI: 10.1074/jbc.m111.280131] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2011] [Revised: 08/24/2011] [Indexed: 11/06/2022] Open
Abstract
Okenone is a unique ketocarotenoid found in many purple sulfur bacteria; it is important because of its unique light absorption and photoprotection properties. Okenane, a compound formed by diagenetic reduction of okenone, is an important biomarker in geochemical analyses of sedimentary rocks. Despite its ecological and biogeochemical importance, the biochemical pathway for okenone synthesis has not yet been fully described. The genome sequence of an okenone-producing organism, Thiodictyon sp. strain CAD16, revealed four genes whose predicted proteins had strong sequence similarity to enzymes known to produce ψ-end group modifications of carotenoids in proteobacteria. These four genes encoded homologs of a 1,2-carotenoid hydratase (CrtC), an O-methyltransferase (CrtF), and two paralogs of carotenoid 3,4-desaturases (CrtD). Expression studies in lycopene- or neurosporene-producing strains of Escherichia coli confirmed the functions of crtC and crtF, but the crtD paralogs encoded enzymes with previously undescribed functions. One enzyme, CruS, was only distantly related to CrtD desaturases, was bifunctional, and performed a 3,4-desaturation and introduced a C-2 keto group into neurosporene derivatives in the presence of dioxygen. The enzyme encoded by the other crtD paralog also represents a new enzyme in carotenogenesis and was named cruO. CruO encodes the C-4/4' ketolase uniquely required for okenone biosynthesis. The identification of CruO and the demonstration of its biochemical activity complete the elucidation of the biosynthetic pathway for okenone and other related ketocarotenoids.
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Affiliation(s)
- Kajetan Vogl
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Donald A Bryant
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802; Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717.
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Hiseni A, Arends IWCE, Otten LG. Biochemical characterization of the carotenoid 1,2-hydratases (CrtC) from Rubrivivax gelatinosus and Thiocapsa roseopersicina. Appl Microbiol Biotechnol 2011; 91:1029-36. [PMID: 21590288 PMCID: PMC3145076 DOI: 10.1007/s00253-011-3324-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2011] [Revised: 04/03/2011] [Accepted: 04/09/2011] [Indexed: 11/28/2022]
Abstract
Two carotenoid 1,2-hydratase (CrtC) genes from the photosynthetic bacteria Rubrivivax gelatinosus and Thiocapsa roseopersicina were cloned and expressed in Escherichia coli in an active form and purified by affinity chromatography. The biochemical properties of the recombinant enzymes and their substrate specificities were studied. The purified CrtCs catalyze cofactor independently the conversion of lycopene to 1-HO- and 1,1′-(HO)2-lycopene. The optimal pH and temperature for hydratase activity was 8.0 and 30°C, respectively. The apparent Km and Vmax values obtained for the hydration of lycopene were 24 μM and 0.31 nmol h−1 mg−1 for RgCrtC and 9.5 μM and 0.15 nmol h−1 mg−1 for TrCrtC, respectively. Sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis revealed two protein bands of 44 and 38 kDa for TrCrtC, which indicate protein processing. Both hydratases are also able to convert the unnatural substrate geranylgeraniol (C20 substrate), which functionally resembles the natural substrate lycopene.
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Affiliation(s)
- Aida Hiseni
- Biocatalysis and Organic Chemistry, Department of Biotechnology, Delft University of Technology, Julianalaan 136, 2628 BL Delft, The Netherlands
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Taylor MP, van Zyl L, Tuffin IM, Leak DJ, Cowan DA. Genetic tool development underpins recent advances in thermophilic whole-cell biocatalysts. Microb Biotechnol 2011; 4:438-48. [PMID: 21310009 PMCID: PMC3815256 DOI: 10.1111/j.1751-7915.2010.00246.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The environmental value of sustainably producing bioproducts from biomass is now widely appreciated, with a primary target being the economic production of fuels such as bioethanol from lignocellulose. The application of thermophilic prokaryotes is a rapidly developing niche in this field, driven by their known catabolic versatility with lignocellulose-derived carbohydrates. Fundamental to the success of this work has been the development of reliable genetic and molecular systems. These technical tools are now available to assist in the development of other (hyper)thermophilic strains with diverse phenotypes such as hemicellulolytic and cellulolytic properties, branched chain alcohol production and other 'valuable bioproduct' synthetic capabilities. Here we present an insight into the historical limitations, recent developments and current status of a number of genetic systems for thermophiles. We also highlight the value of reliable genetic methods for increasing our knowledge of thermophile physiology. We argue that the development of robust genetic systems is paramount in the evolution of future thermophilic based bioprocesses and make suggestions for future approaches and genetic targets that will facilitate this process.
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Affiliation(s)
- M P Taylor
- Institute for Microbial Biotechnology and Metagenomics (IMBM), University of the Western Cape, Modderdam Road, Bellville 7535, Cape Town, South Africa
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Tian B, Hua Y. Carotenoid biosynthesis in extremophilic Deinococcus–Thermus bacteria. Trends Microbiol 2010; 18:512-20. [DOI: 10.1016/j.tim.2010.07.007] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2010] [Revised: 07/19/2010] [Accepted: 07/30/2010] [Indexed: 10/19/2022]
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Phylogenetic and evolutionary patterns in microbial carotenoid biosynthesis are revealed by comparative genomics. PLoS One 2010; 5:e11257. [PMID: 20582313 PMCID: PMC2889829 DOI: 10.1371/journal.pone.0011257] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2010] [Accepted: 05/28/2010] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Carotenoids are multifunctional, taxonomically widespread and biotechnologically important pigments. Their biosynthesis serves as a model system for understanding the evolution of secondary metabolism. Microbial carotenoid diversity and evolution has hitherto been analyzed primarily from structural and biosynthetic perspectives, with the few phylogenetic analyses of microbial carotenoid biosynthetic proteins using either used limited datasets or lacking methodological rigor. Given the recent accumulation of microbial genome sequences, a reappraisal of microbial carotenoid biosynthetic diversity and evolution from the perspective of comparative genomics is warranted to validate and complement models of microbial carotenoid diversity and evolution based upon structural and biosynthetic data. METHODOLOGY/PRINCIPAL FINDINGS Comparative genomics were used to identify and analyze in silico microbial carotenoid biosynthetic pathways. Four major phylogenetic lineages of carotenoid biosynthesis are suggested composed of: (i) Proteobacteria; (ii) Firmicutes; (iii) Chlorobi, Cyanobacteria and photosynthetic eukaryotes; and (iv) Archaea, Bacteroidetes and two separate sub-lineages of Actinobacteria. Using this phylogenetic framework, specific evolutionary mechanisms are proposed for carotenoid desaturase CrtI-family enzymes and carotenoid cyclases. Several phylogenetic lineage-specific evolutionary mechanisms are also suggested, including: (i) horizontal gene transfer; (ii) gene acquisition followed by differential gene loss; (iii) co-evolution with other biochemical structures such as proteorhodopsins; and (iv) positive selection. CONCLUSIONS/SIGNIFICANCE Comparative genomics analyses of microbial carotenoid biosynthetic proteins indicate a much greater taxonomic diversity then that identified based on structural and biosynthetic data, and divides microbial carotenoid biosynthesis into several, well-supported phylogenetic lineages not evident previously. This phylogenetic framework is applicable to understanding the evolution of specific carotenoid biosynthetic proteins or the unique characteristics of carotenoid biosynthetic evolution in a specific phylogenetic lineage. Together, these analyses suggest a "bramble" model for microbial carotenoid biosynthesis whereby later biosynthetic steps exhibit greater evolutionary plasticity and reticulation compared to those closer to the biosynthetic "root". Structural diversification may be constrained ("trimmed") where selection is strong, but less so where selection is weaker. These analyses also highlight likely productive avenues for future research and bioprospecting by identifying both gaps in current knowledge and taxa which may particularly facilitate carotenoid diversification.
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Sozer O, Komenda J, Ughy B, Domonkos I, Laczkó-Dobos H, Malec P, Gombos Z, Kis M. Involvement of carotenoids in the synthesis and assembly of protein subunits of photosynthetic reaction centers of Synechocystis sp. PCC 6803. PLANT & CELL PHYSIOLOGY 2010; 51:823-35. [PMID: 20231245 DOI: 10.1093/pcp/pcq031] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The crtB gene of Synechocystis sp. PCC 6803, encoding phytoene synthase, was inactivated in the Delta crtH mutant to generate a carotenoidless Delta crtH/B double mutant. Delta crtH mutant cells were used because they had better transformability than wild-type cells, most probably due to their adaptation to partial carotenoid deficiency. Cells of the Delta crtH/B mutant were light sensitive and could grow only under light-activated heterotrophic growth conditions in the presence of glucose. Carotenoid deficiency did not significantly affect the cellular content of phycobiliproteins while the chlorophyll content of the mutant cells decreased. The mutant cells exhibited no oxygen-evolving activity, suggesting the absence of photochemically active PSII complexes. This was confirmed by 2D electrophoresis of photosynthetic membrane complexes. Analyses identified only a small amount of a non-functional PSII core complex lacking CP43, while the monomeric and dimeric PSII core complexes were absent. On the other hand, carotenoid deficiency did not prevent formation of the cytochrome b(6)f complex and PSI, which predominantly accumulated in the monomeric form. Radioactive labeling revealed very limited synthesis of inner PSII antennae, CP47 and especially CP43. Thus, carotenoids are indispensable constituents of the photosynthetic apparatus, being essential not only for antioxidative protection but also for the efficient synthesis and accumulation of photosynthetic proteins and especially that of PSII antenna subunits.
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Affiliation(s)
- Ozge Sozer
- Institute of Plant Biology, Biological Research Center, Hungarian Academy of Sciences, Szeged, Hungary
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Chen Y, Li F, Wurtzel ET. Isolation and characterization of the Z-ISO gene encoding a missing component of carotenoid biosynthesis in plants. PLANT PHYSIOLOGY 2010; 153:66-79. [PMID: 20335404 PMCID: PMC2862425 DOI: 10.1104/pp.110.153916] [Citation(s) in RCA: 145] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2010] [Accepted: 03/19/2010] [Indexed: 05/18/2023]
Abstract
Metabolic engineering of plant carotenoids in food crops has been a recent focus for improving human health. Pathway manipulation is predicated on comprehensive knowledge of this biosynthetic pathway, which has been extensively studied. However, there existed the possibility of an additional biosynthetic step thought to be dispensable because it could be compensated for by light. This step, mediated by a putative Z-ISO, was predicted to occur in the sequence of redox reactions that are coupled to an electron transport chain and convert the colorless 15-cis-phytoene to the red-colored all-trans-lycopene. The enigma of carotenogenesis in the absence of light (e.g. in endosperm, a target for improving nutritional content) argued for Z-ISO as a pathway requirement. Therefore, understanding of plant carotenoid biosynthesis was obviously incomplete. To prove the existence of Z-ISO, maize (Zea mays) and Arabidopsis (Arabidopsis thaliana) mutants were isolated and the gene identified. Functional testing of the gene product in Escherichia coli showed isomerization of the 15-cis double bond in 9,15,9'-tri-cis-zeta-carotene, proving that Z-ISO encoded the missing step. Z-ISO was found to be important for both light-exposed and "dark" tissues. Comparative genomics illuminated the origin of Z-ISO found throughout higher and lower plants, algae, diatoms, and cyanobacteria. Z-ISO evolved from an ancestor related to the NnrU (for nitrite and nitric oxide reductase U) gene required for bacterial denitrification, a pathway that produces nitrogen oxides as alternate electron acceptors for anaerobic growth. Therefore, plant carotenogenesis evolved by recruitment of genes from noncarotenogenic bacteria.
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Ng C, DeMaere MZ, Williams TJ, Lauro FM, Raftery M, Gibson JAE, Andrews-Pfannkoch C, Lewis M, Hoffman JM, Thomas T, Cavicchioli R. Metaproteogenomic analysis of a dominant green sulfur bacterium from Ace Lake, Antarctica. ISME JOURNAL 2010; 4:1002-19. [PMID: 20237513 DOI: 10.1038/ismej.2010.28] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Green sulfur bacteria (GSB) (Chlorobiaceae) are primary producers that are important in global carbon and sulfur cycling in natural environments. An almost complete genome sequence for a single, dominant GSB species ('C-Ace') was assembled from shotgun sequence data of an environmental sample taken from the O(2)-H(2)S interface of the water column of Ace Lake, Antarctica. Approximately 34 Mb of DNA sequence data were assembled into nine scaffolds totaling 1.79 Mb, representing approximately 19-fold coverage for the C-Ace composite genome. A high level ( approximately 31%) of metaproteomic coverage was achieved using matched biomass. The metaproteogenomic approach provided unique insight into the protein complement required for dominating the microbial community under cold, nutrient-limited, oxygen-limited and extremely varied annual light conditions. C-Ace shows physiological traits that promote its ability to compete very effectively with other GSB and gain dominance (for example, specific bacteriochlorophylls, mechanisms of cold adaptation) as well as a syntrophic relationship with sulfate-reducing bacteria that provides a mechanism for the exchange of sulfur compounds. As a result we are able to propose an explanation of the active biological processes promoted by cold-adapted GSB and the adaptive strategies they use to thrive under the severe physiochemical conditions prevailing in polar environments.
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Affiliation(s)
- Charmaine Ng
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, New South Wales, Australia
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Takaichi S, Maoka T, Takasaki K, Hanada S. Carotenoids of Gemmatimonas aurantiaca (Gemmatimonadetes): identification of a novel carotenoid, deoxyoscillol 2-rhamnoside, and proposed biosynthetic pathway of oscillol 2,2′-dirhamnoside. Microbiology (Reading) 2010; 156:757-763. [DOI: 10.1099/mic.0.034249-0] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Gemmatimonas aurantiaca strain T-27T is an orange-coloured, Gram-negative, facultatively aerobic, polyphosphate-accumulating bacterium belonging to a recently proposed phylum, Gemmatimonadetes. We purified its pigments and identified them as carotenoids and their glycoside derivatives using spectral data. The major carotenoid was (2S,2′S)-oscillol 2,2′-di-(α-l-rhamnoside), and the minor carotenoids were (2S)-deoxyoscillol 2-(α-l-rhamnoside) and didemethylspirilloxanthin. Deoxyoscillol2-rhamnoside is a novel carotenoid. Oscillol 2,2′-diglycosides have hitherto only been reported in a limited number of cyanobacteria, and this is believed to be the first finding of such carotenoids in another bacterial phylum. Based on the identification of the carotenoids and the completion of the entire nucleotide sequence, we propose a biosynthetic pathway for the carotenoids and the corresponding genes and enzymes. We propose the involvement of geranylgeranyl pyrophosphate synthase (CrtE), phytoene synthase (CrtB) and phytoene desaturase (CrtI) for lycopene synthesis; and of carotenoid1,2-hydratase (CruF) and carotenoid 2-O-rhamnosyltransferase (CruG) for oscillol 2,2′-dirhamnoside synthesis. Further, isopentenyl pyrophosphate could be synthesized by a non-mevalonate pathway (DXP pathway).
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Affiliation(s)
- Shinichi Takaichi
- Department of Biology, Nippon Medical School, Kosugi-cho2, Nakahara, Kawasaki 211-0063, Japan
| | - Takashi Maoka
- Research Institute for Production Development, Shimogamo-morimoto-cho, Sakyo, Kyoto 606-0805, Japan
| | - Kazuto Takasaki
- Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8566, Japan
| | - Satoshi Hanada
- Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8566, Japan
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Maresca JA, Braff JC, Delong EF. Characterization of canthaxanthin biosynthesis genes from an uncultured marine bacterium. ENVIRONMENTAL MICROBIOLOGY REPORTS 2009; 1:524-534. [PMID: 23765931 DOI: 10.1111/j.1758-2229.2009.00075.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Carotenoids are isoprenoid pigments synthesized in plants, fungi, bacteria and archaea, with roles in light harvesting, protection from stress, and membrane and protein structures. To characterize carotenoid biosynthesis genes from oceanic microbes, a fosmid library derived from microbial samples collected in surface water of the Pacific Ocean was screened in Escherichia coli for pigment-expressing recombinant strains. One DNA fragment enabled production of a bright orange pigment, and was analysed further by sequence analysis and phenotypic characterization. The cloned DNA encoded a five-gene cluster predicted to be involved in the synthesis of canthaxanthin, a ketolated carotenoid. Each of these genes was inactivated by insertion of a transposon, and the biochemical function of each gene product was confirmed. Sequencing of related fosmids generated a 67 kb genomic contig, and comparative analyses suggested that the DNA may originate from a deltaproteobacterium. The carotenoid biosynthesis genes described here are related to well-characterized families of carotenoid biosynthesis genes, but also indicate that the organism harbouring them is only distantly related to any previously characterized bacterial types.
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Affiliation(s)
- Julia A Maresca
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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Li H, Jubelirer S, Garcia Costas AM, Frigaard NU, Bryant DA. Multiple antioxidant proteins protect Chlorobaculum tepidum against oxygen and reactive oxygen species. Arch Microbiol 2009; 191:853-67. [PMID: 19784828 DOI: 10.1007/s00203-009-0514-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2009] [Revised: 08/31/2009] [Accepted: 09/14/2009] [Indexed: 11/25/2022]
Abstract
The genome of the green sulfur bacterium Chlorobaculum (Cba.) tepidum, a strictly anaerobic photolithoautotroph, is predicted to encode more than ten genes whose products are potentially involved in protection from reactive oxygen species and an oxidative stress response. The encoded proteins include cytochrome bd quinol oxidase, NADH oxidase, rubredoxin oxygen oxidoreductase, several thiol peroxidases, alkyl hydroperoxide reductase, superoxide dismutase, methionine sulfoxide reductase, and rubrerythrin. To test the physiological functions of some of these proteins, ten genes were insertionally inactivated. Wild-type Cba. tepidum cells were very sensitive to oxygen in the light but were remarkably resistant to oxygen in the dark. When wild-type and mutant cells were subjected to air for various times under dark or light condition, significant decreases in viability were detected in most of the mutants relative to wild type. Treatments with hydrogen peroxide (H(2)O(2)), tert-butyl hydroperoxide (t-BOOH) and methyl viologen resulted in more severe effects in most of the mutants than in the wild type. The results demonstrated that these putative antioxidant proteins combine to form an effective defense against oxygen and reactive oxygen species. Reverse-transcriptase polymerase chain reaction studies showed that the genes with functions in oxidative stress protection were constitutively transcribed under anoxic growth conditions.
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Affiliation(s)
- Hui Li
- Department of Biochemistry and Molecular Biology and Center for Biomolecular Structure and Function, The Pennsylvania State University , S-235 Frear Building, University Park, PA 16802, USA
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Envelope proteins of the CsmB/CsmF and CsmC/CsmD motif families influence the size, shape, and composition of chlorosomes in Chlorobaculum tepidum. J Bacteriol 2009; 191:7109-20. [PMID: 19749040 DOI: 10.1128/jb.00707-09] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The chlorosome envelope of Chlorobaculum tepidum contains 10 proteins that belong to four structural motif families. A previous mutational study (N.-U. Frigaard, H. Li, K. J. Milks, and D. A. Bryant, J. Bacteriol. 186:646-653, 2004) suggested that some of these proteins might have redundant functions. Six multilocus mutants were constructed to test the effects of eliminating the proteins of the CsmC/CsmD and CsmB/CsmF motif families, and the resulting strains were characterized physiologically and biochemically. Mutants lacking all proteins of either motif family still assembled functional chlorosomes, and as measured by growth rates of the mutant strains, light harvesting was affected only at the lowest light intensities tested (9 and 32 micromol photons m(-2) s(-1)). The size, composition, and biogenesis of the mutant chlorosomes differed from those of wild-type chlorosomes. Mutants lacking proteins of the CsmC/CsmD motif family produced smaller chlorosomes than did the wild type, and the Q(y) absorbance maximum for the bacteriochlorophyll c aggregates in these chlorosomes was strongly blueshifted. Conversely, the chlorosomes of mutants lacking proteins of the CsmB/CsmF motif family were larger than wild-type chlorosomes, and the Q(y) absorption for their bacteriochlorophyll c aggregates was redshifted. When CsmH was eliminated in addition to other proteins of either motif family, chlorosomes had smaller diameters. These data show that the chlorosome envelope proteins of the CsmB/CsmF and CsmC/CsmD families play important roles in determining chlorosome size as well as the assembly and supramolecular organization of the bacteriochlorophyll c aggregates within the chlorosome.
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Sun Z, Shen S, Wang C, Wang H, Hu Y, Jiao J, Ma T, Tian B, Hua Y. A novel carotenoid 1,2-hydratase (CruF) from two species of the non-photosynthetic bacterium Deinococcus. MICROBIOLOGY-SGM 2009; 155:2775-2783. [PMID: 19443548 DOI: 10.1099/mic.0.027623-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A novel carotenoid 1,2-hydratase (CruF) responsible for the C-1',2' hydration of gamma-carotene was identified in the non-photosynthetic bacteria Deinococcus radiodurans R1 and Deinococcus geothermalis DSM 11300. Gene expression and disruption experiments demonstrated that dr0091 and dgeo2309 encode CruF in D. radiodurans and D. geothermalis, respectively. Their homologues were also found in the genomes of cyanobacteria, and exhibited little homology to the hydroxyneurosporene synthase (CrtC) proteins found mainly in photosynthetic bacteria. Phylogenetic analysis showed that CruF homologues form a separate family, which is evolutionarily distant from the known CrtC family.
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Affiliation(s)
- Zongtao Sun
- Key Laboratory for Nuclear-Agricultural Sciences of Chinese Ministry of Agriculture and Zhejiang Province, Institute of Nuclear-Agricultural Sciences, Zhejiang University, 310029 Hangzhou, China
| | - Shaochuan Shen
- State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology, College of Chemical Engineering and Materials Science, Zhejiang University of Technology, 310032 Hangzhou, China.,Key Laboratory for Nuclear-Agricultural Sciences of Chinese Ministry of Agriculture and Zhejiang Province, Institute of Nuclear-Agricultural Sciences, Zhejiang University, 310029 Hangzhou, China
| | - Chao Wang
- Key Laboratory for Nuclear-Agricultural Sciences of Chinese Ministry of Agriculture and Zhejiang Province, Institute of Nuclear-Agricultural Sciences, Zhejiang University, 310029 Hangzhou, China
| | - Hu Wang
- Key Laboratory for Nuclear-Agricultural Sciences of Chinese Ministry of Agriculture and Zhejiang Province, Institute of Nuclear-Agricultural Sciences, Zhejiang University, 310029 Hangzhou, China
| | - Yaping Hu
- Key Laboratory for Nuclear-Agricultural Sciences of Chinese Ministry of Agriculture and Zhejiang Province, Institute of Nuclear-Agricultural Sciences, Zhejiang University, 310029 Hangzhou, China
| | - Jiandong Jiao
- Key Laboratory for Nuclear-Agricultural Sciences of Chinese Ministry of Agriculture and Zhejiang Province, Institute of Nuclear-Agricultural Sciences, Zhejiang University, 310029 Hangzhou, China
| | - Tingting Ma
- Key Laboratory for Nuclear-Agricultural Sciences of Chinese Ministry of Agriculture and Zhejiang Province, Institute of Nuclear-Agricultural Sciences, Zhejiang University, 310029 Hangzhou, China
| | - Bing Tian
- Key Laboratory for Nuclear-Agricultural Sciences of Chinese Ministry of Agriculture and Zhejiang Province, Institute of Nuclear-Agricultural Sciences, Zhejiang University, 310029 Hangzhou, China
| | - Yuejin Hua
- Key Laboratory for Nuclear-Agricultural Sciences of Chinese Ministry of Agriculture and Zhejiang Province, Institute of Nuclear-Agricultural Sciences, Zhejiang University, 310029 Hangzhou, China
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The biosynthetic pathway for myxol-2' fucoside (myxoxanthophyll) in the cyanobacterium Synechococcus sp. strain PCC 7002. J Bacteriol 2009; 191:3292-300. [PMID: 19304845 DOI: 10.1128/jb.00050-09] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Synechococcus sp. strain PCC 7002 produces a variety of carotenoids, which comprise predominantly dicylic beta-carotene and two dicyclic xanthophylls, zeaxanthin and synechoxanthin. However, this cyanobacterium also produces a monocyclic myxoxanthophyll, which was identified as myxol-2' fucoside. Compared to the carotenoid glycosides produced by diverse microorganisms, cyanobacterial myxoxanthophyll and closely related compounds are unusual because they are glycosylated on the 2'-OH rather than on the 1'-OH position of the psi end of the molecule. In this study, the genes encoding two enzymes that modify the psi end of myxoxanthophyll in Synechococcus sp. strain PCC 7002 were identified. Mutational and biochemical studies showed that open reading frame SynPCC7002_A2032, renamed cruF, encodes a 1',2'-hydroxylase [corrected] and that open reading frame SynPCC7002_A2031, renamed cruG, encodes a 2'-O-glycosyltransferase. The enzymatic activity of CruF was verified by chemical characterization of the carotenoid products synthesized when cruF was expressed in a lycopene-producing strain of Escherichia coli. Database searches showed that homologs of cruF and cruG occur in the genomes of all sequenced cyanobacterial strains that are known to produce myxol or the acylic xanthophyll oscillaxanthin. The genomes of many other bacteria that produce hydroxylated carotenoids but do not contain crtC homologs also contain cruF orthologs. Based upon observable intermediates, a complete biosynthetic pathway for myxoxanthophyll is proposed. This study expands the suite of enzymes available for metabolic engineering of carotenoid biosynthetic pathways for biotechnological applications.
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Sandmann G. Evolution of carotene desaturation: the complication of a simple pathway. Arch Biochem Biophys 2008; 483:169-74. [PMID: 18948076 DOI: 10.1016/j.abb.2008.10.004] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2008] [Revised: 10/02/2008] [Accepted: 10/03/2008] [Indexed: 11/27/2022]
Abstract
In a series of desaturation reactions, the trienoic structures of phytoene and diapophytoene are extended to a maximum of 15 or 11 conjugated double bonds, respectively. After the cloning of several genes from bacteria and eukaryotes, the desaturation reactions were first analyzed in a heterologous host by functional genetic complementation. In addition, different desaturases were heterologously expressed and the reactions studied in vitro. This revealed that in archaea, non-photosynthetic prokaryotes and fungi the desaturases differ significantly from convergently evolved desaturases in cyanobacteria, Chlorobaculum (old name Chlorobium) species and eukaryotic photosynthetic organisms including plants. Detailed analysis of the desaturation reactions including the determination of the substrates converted by the enzymes, the intermediates and the products formed in the reactions revealed the bacterial all-trans desaturation pathway catalyzed by a single enzyme and the cyanobacterial/plant type poly-cis desaturation pathway which involves two closely related desaturases. This indicates that in the course of evolution of carotenogenesis from bacteria via cyanobacteria to plants, the simple situation of one enzyme for the entire reaction sequence from phytoene to all-trans lycopene changed to a more complex process. Three individual enzymes, newly acquired phytoene and zeta-carotene desaturases, as well as a carotene isomerase which is phylogenetically related to CrtI are involved. Only the CrtI-type enzymes seem to have the property to catalyze cis to trans conversion of carotenes.
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Affiliation(s)
- Gerhard Sandmann
- Biosynthesis Group, Molecular Biosciences, J.W. Goethe Universitaet, Biocampus 213, P.O. Box 111932, D-60054 Frankfurt, Germany.
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