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Bernstein PS, Li B, Vachali PP, Gorusupudi A, Shyam R, Henriksen BS, Nolan JM. Lutein, zeaxanthin, and meso-zeaxanthin: The basic and clinical science underlying carotenoid-based nutritional interventions against ocular disease. Prog Retin Eye Res 2016; 50:34-66. [PMID: 26541886 PMCID: PMC4698241 DOI: 10.1016/j.preteyeres.2015.10.003] [Citation(s) in RCA: 324] [Impact Index Per Article: 40.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 10/04/2015] [Accepted: 10/29/2015] [Indexed: 12/31/2022]
Abstract
The human macula uniquely concentrates three carotenoids: lutein, zeaxanthin, and meso-zeaxanthin. Lutein and zeaxanthin must be obtained from dietary sources such as green leafy vegetables and orange and yellow fruits and vegetables, while meso-zeaxanthin is rarely found in diet and is believed to be formed at the macula by metabolic transformations of ingested carotenoids. Epidemiological studies and large-scale clinical trials such as AREDS2 have brought attention to the potential ocular health and functional benefits of these three xanthophyll carotenoids consumed through the diet or supplements, but the basic science and clinical research underlying recommendations for nutritional interventions against age-related macular degeneration and other eye diseases are underappreciated by clinicians and vision researchers alike. In this review article, we first examine the chemistry, biochemistry, biophysics, and physiology of these yellow pigments that are specifically concentrated in the macula lutea through the means of high-affinity binding proteins and specialized transport and metabolic proteins where they play important roles as short-wavelength (blue) light-absorbers and localized, efficient antioxidants in a region at high risk for light-induced oxidative stress. Next, we turn to clinical evidence supporting functional benefits of these carotenoids in normal eyes and for their potential protective actions against ocular disease from infancy to old age.
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Affiliation(s)
- Paul S Bernstein
- Department of Ophthalmology and Visual Sciences, Moran Eye Center, University of Utah School of Medicine, 65 Mario Capecchi Drive, Salt Lake City, UT, 84132, USA.
| | - Binxing Li
- Department of Ophthalmology and Visual Sciences, Moran Eye Center, University of Utah School of Medicine, 65 Mario Capecchi Drive, Salt Lake City, UT, 84132, USA.
| | - Preejith P Vachali
- Department of Ophthalmology and Visual Sciences, Moran Eye Center, University of Utah School of Medicine, 65 Mario Capecchi Drive, Salt Lake City, UT, 84132, USA.
| | - Aruna Gorusupudi
- Department of Ophthalmology and Visual Sciences, Moran Eye Center, University of Utah School of Medicine, 65 Mario Capecchi Drive, Salt Lake City, UT, 84132, USA.
| | - Rajalekshmy Shyam
- Department of Ophthalmology and Visual Sciences, Moran Eye Center, University of Utah School of Medicine, 65 Mario Capecchi Drive, Salt Lake City, UT, 84132, USA.
| | - Bradley S Henriksen
- Department of Ophthalmology and Visual Sciences, Moran Eye Center, University of Utah School of Medicine, 65 Mario Capecchi Drive, Salt Lake City, UT, 84132, USA.
| | - John M Nolan
- Macular Pigment Research Group, Vision Research Centre, School of Health Science, Carriganore House, Waterford Institute of Technology West Campus, Carriganore, Waterford, Ireland.
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Ma T, Zhou Y, Li X, Zhu F, Cheng Y, Liu Y, Deng Z, Liu T. Genome mining of astaxanthin biosynthetic genes from Sphingomonas sp. ATCC 55669 for heterologous overproduction in Escherichia coli. Biotechnol J 2015; 11:228-37. [PMID: 26580858 PMCID: PMC5064606 DOI: 10.1002/biot.201400827] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 08/07/2015] [Accepted: 10/19/2015] [Indexed: 02/01/2023]
Abstract
As a highly valued keto-carotenoid, astaxanthin is widely used in nutritional supplements and pharmaceuticals. Therefore, the demand for biosynthetic astaxanthin and improved efficiency of astaxanthin biosynthesis has driven the investigation of metabolic engineering of native astaxanthin producers and heterologous hosts. However, microbial resources for astaxanthin are limited. In this study, we found that the α-Proteobacterium Sphingomonas sp. ATCC 55669 could produce astaxanthin naturally. We used whole-genome sequencing to identify the astaxanthin biosynthetic pathway using a combined PacBio-Illumina approach. The putative astaxanthin biosynthetic pathway in Sphingomonas sp. ATCC 55669 was predicted. For further confirmation, a high-efficiency targeted engineering carotenoid synthesis platform was constructed in E. coli for identifying the functional roles of candidate genes. All genes involved in astaxanthin biosynthesis showed discrete distributions on the chromosome. Moreover, the overexpression of exogenous E. coli idi in Sphingomonas sp. ATCC 55669 increased astaxanthin production by 5.4-fold. This study described a new astaxanthin producer and provided more biosynthesis components for bioengineering of astaxanthin in the future.
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Affiliation(s)
- Tian Ma
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan University), Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan, China
| | - Yuanjie Zhou
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan University), Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan, China
| | - Xiaowei Li
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan University), Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan, China
| | - Fayin Zhu
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan University), Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan, China
| | - Yongbo Cheng
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan University), Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan, China
| | - Yi Liu
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan University), Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan, China
| | - Zixin Deng
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan University), Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan, China
| | - Tiangang Liu
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan University), Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan, China. .,Hubei Engineering Laboratory for Synthetic Microbiology, Wuhan Institute of Biotechnology, Wuhan, China. .,Hubei Provincial Cooperative Innovation Center of Industrial Fermentation, Wuhan, China.
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3
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Yoon SH, Park HM, Kim JE, Lee SH, Choi MS, Kim JY, Oh DK, Keasling JD, Kim SW. Increased β-Carotene Production in Recombinant Escherichia coli Harboring an Engineered Isoprenoid Precursor Pathway with Mevalonate Addition. Biotechnol Prog 2008; 23:599-605. [PMID: 17500531 DOI: 10.1021/bp070012p] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
When pT-LYCm4 containing lycopene synthetic genes was co-transformed with pSUcrtY or pSHcrtY containing crtY gene of Pantoea ananatis (P. ananatis) or Pantoea agglomerans (P. agglomerans), beta-carotene productions of 36 and 35 mg/L were obtained, respectively. No lycopene was detected in the beta-carotene production culture. pT-HB, constructed by addition of P. ananatis crtY gene into pT-LYCm4, was used for co-transformation with pSdxs and pSSN12Didi, which increased isopentenyl diphosphate and dimethylallyl diphosphate synthesis. beta-Carotene production significantly increased 1.5-fold (51 mg/L) with the amplification of the dxs gene through pSdxs and 4-fold (135 mg/L) with the mevalonate bottom pathway of pSSN12Didi in the presence of 3.3 mM mevalonate. The pT-DHB, constructed by integrating the dxs gene into pT-HB, was used for cotransformation of Escherichia coli (E. coli) harboring pSSN12Didi, resulting in beta-carotene production of 141 mg/L. Recombinant E. coli harboring pT-DHB and pSSN12Didi was used to maximize beta-carotene production by adjusting the available amounts of glycerol, a carbon source, and mevalonate, the precursor of the mevalonate bottom pathway. When recombinant E. coli was given 16.5 mM mevalonate and 2.5% (w/v) glycerol, beta-carotene production of 503 mg/L in concentration and 49.3 mg/g DCW in content was obtained at 144 h, which was the highest level of carotenoid production in E. coli ever reported in the literature.
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Affiliation(s)
- Sang-Hwal Yoon
- Division of Applied Life Science (BK21), EB-NCRC and PMBBRC, and Division of Forest Science, Gyeongsang National University, Jinju 660-701, Korea
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4
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Cunningham FX, Gantt E. A portfolio of plasmids for identification and analysis of carotenoid pathway enzymes: Adonis aestivalis as a case study. PHOTOSYNTHESIS RESEARCH 2007; 92:245-59. [PMID: 17634749 DOI: 10.1007/s11120-007-9210-0] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2007] [Accepted: 05/25/2007] [Indexed: 05/16/2023]
Abstract
Carotenoids are indispensable pigments of the photosynthetic apparatus in plants, algae, and cyanobacteria and are produced, as well, by many bacteria and fungi. Elucidation of biochemical pathways leading to the carotenoids that function in the photosynthetic membranes of land plants has been greatly aided by the use of carotenoid-accumulating strains of Escherichia coli as heterologous hosts for functional assays, in vivo, of the otherwise difficult to study membrane-associated pathway enzymes. This same experimental approach is uniquely well-suited to the discovery and characterization of yet-to-be identified enzymes that lead to carotenoids of the photosynthetic membranes in algal cells, to the multitude of carotenoids found in nongreen plant tissues, and to the myriad flavor and aroma compounds that are derived from carotenoids in plant tissues. A portfolio of plasmids suitable for the production in E. coli of a variety of carotenoids is presented herein. The use of these carotenoid-producing E. coli for the identification of cDNAs encoding enzymes of carotenoid and isoprenoid biosynthesis, for characterization of the enzymes these cDNAs encode, and for the production of specific carotenoids for use as enzyme substrates and reference standards, is described using the flowering plant Adonis aestivalis to provide examples. cDNAs encoding nine different A. aestivalis enzymes of carotenoid and isoprenoid synthesis were identified and the enzymatic activity of their products verified. Those cDNAs newly described include ones that encode phytoene synthase, beta-carotene hydroxylase, deoxyxylulose-5-phosphate synthase, isopentenyl diphosphate isomerase, and geranylgeranyl diphosphate synthase.
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Affiliation(s)
- Francis X Cunningham
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA.
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Nishida Y, Adachi K, Kasai H, Shizuri Y, Shindo K, Sawabe A, Komemushi S, Miki W, Misawa N. Elucidation of a carotenoid biosynthesis gene cluster encoding a novel enzyme, 2,2'-beta-hydroxylase, from Brevundimonas sp. strain SD212 and combinatorial biosynthesis of new or rare xanthophylls. Appl Environ Microbiol 2005; 71:4286-96. [PMID: 16085816 PMCID: PMC1183362 DOI: 10.1128/aem.71.8.4286-4296.2005] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A carotenoid biosynthesis gene cluster mediating the production of 2-hydroxyastaxanthin was isolated from the marine bacterium Brevundimonas sp. strain SD212 by using a common crtI sequence as the probe DNA. A sequence analysis revealed this cluster to contain 12 open reading frames (ORFs), including the 7 known genes, crtW, crtY, crtI, crtB, crtE, idi, and crtZ. The individual ORFs were functionally analyzed by complementation studies using Escherichia coli that accumulated various carotenoid precursors due to the presence of other bacterial crt genes. In addition to functionally identifying the known crt genes, we found that one (ORF11, named crtG) coded for a novel enzyme, carotenoid 2,2'-beta-hydroxylase, which showed intriguingly partial homology with animal sterol-C5-desaturase. When this crtG gene was introduced into E. coli accumulating zeaxanthin and canthaxanthin, the resulting transformants produced their 2-hydroxylated and 2,2'-dihydroxylated products which were structurally novel or rare xanthophylls, as determined by their nuclear magnetic resonance and high-performance liquid chromatography/photodiode array detector/atmospheric pressure chemical ionization mass spectrometry spectral data. The new carotenoid produced was suggested to have a strong inhibitory effect on lipid peroxidation.
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Van Dien SJ, Marx CJ, O'Brien BN, Lidstrom ME. Genetic characterization of the carotenoid biosynthetic pathway in Methylobacterium extorquens AM1 and isolation of a colorless mutant. Appl Environ Microbiol 2004; 69:7563-6. [PMID: 14660416 PMCID: PMC310018 DOI: 10.1128/aem.69.12.7563-7566.2003] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Genomic searches were used to reconstruct the putative carotenoid biosynthesis pathway in the pink-pigmented facultative methylotroph Methylobacterium extorquens AM1. Four genes for putative phytoene desaturases were identified. A colorless mutant was obtained by transposon mutagenesis, and the insertion was shown to be in one of the putative phytoene desaturase genes. Mutations in the other three did not affect color. The tetracycline marker was removed from the original transposon mutant, resulting in a pigment-free strain with wild-type growth properties useful as a tool for future experiments.
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Affiliation(s)
- Stephen J Van Dien
- Department of Chemical Engineering. Department of Microbiology, University of Washington, Seattle, Washington 98195-2180, USA
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Houssaini-Iraqui M, Khamlichi N, Yamani JE, Rastogi N. Response of Escherichia coli Containing Mycobacterial Carotene Genes to UV Radiation. J Biomed Biotechnol 2001; 1:79-84. [PMID: 12488613 PMCID: PMC113779 DOI: 10.1155/s1110724301000225] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
The plasmid pC5, which encodes biogenesis of lycopene in Mycobacterium aurum A(+), was partially digested by restriction endonucleases and generated fragments were cloned. After transformation of Escherichia coli (colorless bacteria) with the plasmids so constructed, seven orange clones were detected and found to carry the same recombinant plasmid (pC51). E. coli cells containing this plasmid synthesize neurosporene and lycopene, and were more resistant to ultraviolet irradiation than non pigmented strain.
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Affiliation(s)
- Mohamed Houssaini-Iraqui
- Biotechnology Laboratory, Sidi Mohammed Ben Abdellah
University, FST, P.O. Box 2202, Fez, Morocco
| | - Naima Khamlichi
- Biotechnology Laboratory, Sidi Mohammed Ben Abdellah
University, FST, P.O. Box 2202, Fez, Morocco
| | - Jamal El Yamani
- Biotechnology Laboratory, Sidi Mohammed Ben Abdellah
University, FST, P.O. Box 2202, Fez, Morocco
| | - Nalin Rastogi
- Tuberculosis and Mycobacteria unit, Pasteur Institut, P.O.
Box 484, Pointe a Pitre Guadeloupe, France
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Abstract
Carotenoids are integral and essential components of the photosynthetic membranes in all plants. Within the past few years, genes encoding nearly all of the enzymes required for the biosynthesis of these indispensable pigments have been identified. This review focuses on recent findings as to the structure and function of these genes and the enzymes they encode. Three topics of current interest are also discussed: the source of isopentenyl pyrophosphate for carotenoid biosynthesis, the progress and possibilities of metabolic engineering of plants to alter carotenoid content and composition, and the compartmentation and association of the carotenogenic enzymes. A speculative schematic model of carotenogenic enzyme complexes is presented to help frame and provoke insightful questions leading to future experimentation.
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Affiliation(s)
- F. X. Cunningham
- Department of Microbiology, University of Maryland, College Park, MD 20742; e-mail: ;
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Schnurr G, Misawa N, Sandmann G. Expression, purification and properties of lycopene cyclase from Erwinia uredovora. Biochem J 1996; 315 ( Pt 3):869-74. [PMID: 8645170 PMCID: PMC1217287 DOI: 10.1042/bj3150869] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Lycopene cyclase, an enzyme responsible for the formation of cyclic carotenoids from acyclic precursors has been purified to homogeneity in an active state. The Erwinia uredovora lycopene cyclase gene (crtY) was over-expressed in Escherichia coli. From this recombinant strain the enzyme was purified by immuno-affinity chromatography and its cyclization activity characterized as a two-step reaction in which both sides of the lycopene molecule are cyclized to beta-ionone rings with the monocyclic gamma-carotene as an intermediate. Furthermore, neurosporene as well as l-hydroxylycopene were cyclized to beta-zeacarotene and hydroxy-gamma-carotene respectively. In contrast, neither 1,1'- dihydroxylycopene nor the tetra-cis-prolycopene were accepted as substrates. The cofactors involved in the reaction were either NADH or NADPH. K(m) values were determined for lycopene and NADPH to be 1.8 microM and 2.5 mM respectively.
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Affiliation(s)
- G Schnurr
- Lehrstuhl für Physiologie und Biochemie der Pflanzen, Universität Konstanz, Federal Republic of Germany
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Botella JA, Murillo FJ, Ruiz-Vázquez R. A cluster of structural and regulatory genes for light-induced carotenogenesis in Myxococcus xanthus. EUROPEAN JOURNAL OF BIOCHEMISTRY 1995; 233:238-48. [PMID: 7588751 DOI: 10.1111/j.1432-1033.1995.238_1.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
In the bacterium Myxococcus xanthus, several genes for carotenoid synthesis lie together at the carA-carB chromosomal locus and are co-ordinately activated by blue light. A 12-kb DNA stretch from wild-type M. xanthus has been sequenced that includes the entire carA-carB gene cluster. According to sequence analysis, the cluster contains 11 different genes. Intergenic distances are very short or nil (implying translational coupling), giving further support to previous evidence indicating that most (or all) of the genes in the cluster form a single operon. At the promoter region, a potential -35 site for the binding of sigma factors is found. However, the -10 region shows little similarity with analogous sites in other bacterial promoters. Five (possibly six) genes in the carA-carB operon code for enzymes acting on early or late steps of the pathway for carotenoid synthesis. Other genes in the operon show no overall similarity with previously known genes. However, peptide stretches in the predicted products of two genes exhibit strong similarity with the DNA binding domain of the MerR family of transcriptional regulators. At least one of the predicted DNA-binding domains is altered in a mutant strain affected in light-regulation of the car genes.
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Affiliation(s)
- J A Botella
- Departamento de Genética y Microbiología, Facultad de Biología, Universidad de Murcia, Spain
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11
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Lin TP, Lai EM, To KY, Chang YS, Liu ST. Transcriptional activation of flanking sequences by Tn1000 insertion. MOLECULAR & GENERAL GENETICS : MGG 1994; 245:417-23. [PMID: 7808390 DOI: 10.1007/bf00302253] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The carotenoid biosynthesis operon of Erwinia herbicola Eho13 consists of five genes, which are organized in the order crtE-crtX-crtY-crtI-crtB. These genes, with the exception of crtX, encode functions of beta-carotene biosynthesis and give an orange-coloured phenotype in Escherichia coli. Since crtX is not involved in the biosynthesis of beta-carotene, deletion of this gene does not alter the phenotype of pigmented cells. On the other hand, insertion of Tn1000 into crtX or into the upstream untranslated region of the operon resulted in a light-yellow, rather than an unpigmented phenotype, indicating that Tn1000 does not exert a strong polar effect when inserted in this operon. RNA analysis revealed that the sequence downstream from the insertion site was transcribed at a low level. Primer extension showed that the "-35"-like sequence in the terminal inverted repeats was not responsible for the transcription of the downstream sequence. Furthermore, primer extension and polymerase chain reaction (PCR) studies revealed that RNA transcribed from the promoters inside of Tn1000 was extended through the terminal inverted repeats into the adjacent sequences. In addition Tn1000, in either orientation, was able to generate fusion transcripts when placed upstream of a promoter-less tetracycline-resistance gene and resulted in cells resistant to the drug. These results showed that Tn1000 insertion transcriptionally activates the DNA sequences adjacent to the transposon.
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Affiliation(s)
- T P Lin
- Institute of Biotechnology, Chinese Culture University, Taipei, Taiwan
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Affiliation(s)
- G Sandmann
- Botanisches Institut, FB Biologie, J.W. Goethe Universität, Frankfurt, Germany
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Hunter CN, Hundle BS, Hearst JE, Lang HP, Gardiner AT, Takaichi S, Cogdell RJ. Introduction of new carotenoids into the bacterial photosynthetic apparatus by combining the carotenoid biosynthetic pathways of Erwinia herbicola and Rhodobacter sphaeroides. J Bacteriol 1994; 176:3692-7. [PMID: 8206847 PMCID: PMC205558 DOI: 10.1128/jb.176.12.3692-3697.1994] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Carotenoids have two major functions in bacterial photosynthesis, photoprotection and accessory light harvesting. The genes encoding many carotenoid biosynthetic pathways have now been mapped and cloned in several different species, and the availability of cloned genes which encode the biosynthesis of carotenoids not found in the photosynthetic genus Rhodobacter opens up the possibility of introducing a wider range of foreign carotenoids into the bacterial photosynthetic apparatus than would normally be available by producing mutants of the native biosynthetic pathway. For example, the crt genes from Erwinia herbicola, a gram-negative nonphotosynthetic bacterium which produces carotenoids in the sequence of phytoene, lycopene, beta-carotene, beta-cryptoxanthin, zeaxanthin, and zeaxanthin glucosides, are clustered within a 12.8-kb region and have been mapped and partially sequenced. In this paper, part of the E. herbicola crt cluster has been excised and expressed in various crt strains of Rhodobacter sphaeroides. This has produced light-harvesting complexes with a novel carotenoid composition, in which the foreign carotenoids such as beta-carotene function successfully in light harvesting. The outcome of the combination of the crt genes in R. sphaeroides with those from E. herbicola has, in some cases, resulted in an interesting rerouting of the expected biosynthetic sequence, which has also provided insights into how the various enzymes of the carotenoid biosynthetic pathway might interact. Clearly this approach has considerable potential for studies on the control and organization of carotenoid biosynthesis, as well as providing novel pigment-protein complexes for functional studies.
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Affiliation(s)
- C N Hunter
- Department of Molecular Biology, University of Sheffield, United Kingdom
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14
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Garà E, Toledo JC, Gibert I, Barbé J. Nucleotide sequence of the methoxyneurosporene dehydrogenase gene from Rhodobacter sphaeroides: Comparison with other bacterial carotenoid dehydrogenases. FEMS Microbiol Lett 1992. [DOI: 10.1111/j.1574-6968.1992.tb05048.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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