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Ye RY, Song J, Zhang ZJ, Yu HL. Prokaryotic expression and characterization of artificial self-sufficient CYP120A monooxygenases. Appl Microbiol Biotechnol 2023; 107:5727-5737. [PMID: 37477695 DOI: 10.1007/s00253-023-12678-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 06/20/2023] [Accepted: 06/30/2023] [Indexed: 07/22/2023]
Abstract
Cytochrome P450 monooxygenases CYP120As are the unique non-membrane P450s, which are extensively involved in retinoid biodegradation. As the O-functionalized 1,3,3-trimethylcyclohex-1-ene moiety exists in many bioactive compounds which could only be catalyzed by Class II P450s, exploration of the catalytic repertoire of CYP120As is therefore highly attractive. However, up to date, only one bacteriogenic candidate (CYP120A1) was demonstrated for the hydroxylation of C16 and C17 of retinoic acid, by utilizing the integral membrane protein cytochrome P450 reductase redox partner for the electron transfer. Herein, we provided an efficient prokaryotic functional expression system of CYP120As in E. coli by expression of the CYP120A1 coupled with several reductase partners. Fusion redox partners to the C-terminal of the heme-domain are also working on other CYP120A members. Among them, the fusion protein of CYP120A29 and FAD/FMN reductase from Bacillus megaterium P450BM3 (CYP101A2) showed the highest expression level. Based on the available translational fusion systems, the regioselectivity and the substrate scope of the CYP120As have also been explored. This work represents a good starting point for further expanding the catalytic potential of CYP120 family. KEY POINTS: • Characterization of CYP120As in E. coli is firstly achieved by constructing fusion proteins. • The feasibility of three P450 reductase domains to CYP120As was evaluated. • Hydroxylated products of retinoic acid by six CYP120As were sorted and analyzed.
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Affiliation(s)
- Ru-Yi Ye
- State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Centre for Biomanufacturing, College of Biotechnology, East China University of Science and Technology, Shanghai, 200237, People's Republic of China
| | - Juan Song
- State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Centre for Biomanufacturing, College of Biotechnology, East China University of Science and Technology, Shanghai, 200237, People's Republic of China
| | - Zhi-Jun Zhang
- State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Centre for Biomanufacturing, College of Biotechnology, East China University of Science and Technology, Shanghai, 200237, People's Republic of China
| | - Hui-Lei Yu
- State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Centre for Biomanufacturing, College of Biotechnology, East China University of Science and Technology, Shanghai, 200237, People's Republic of China.
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Sehnal L, Smutná M, Bláhová L, Babica P, Šplíchalová P, Hilscherová K. The Origin of Teratogenic Retinoids in Cyanobacteria. Toxins (Basel) 2022; 14:toxins14090636. [PMID: 36136574 PMCID: PMC9501733 DOI: 10.3390/toxins14090636] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 09/01/2022] [Accepted: 09/13/2022] [Indexed: 11/16/2022] Open
Abstract
Although information about the occurrence and distribution of retinoids in the environment is scarce, cyanobacterial water blooms have been identified as a significant source of these small molecules. Despite the confirmed presence of retinoids in the freshwater blooms dominated by cyanobacteria and their described teratogenic effects, reliable identification of retinoid producers and the mechanism of their biosynthesis is missing. In this study, the cultures of several taxonomically diverse species of axenic cyanobacteria were confirmed as significant producers of retinoid-like compounds. The consequent bioinformatic analysis suggested that the enzymatic background required for the biosynthesis of all-trans retinoic acid from retinal is not present across phylum Cyanobacteria. However, we demonstrated that retinal conversion into other retinoids can be mediated non-enzymatically by free radical oxidation, which leads to the production of retinoids widely detected in cyanobacteria and environmental water blooms, such as all-trans retinoic acid or all-trans 5,6epoxy retinoic acid. Importantly, the production of these metabolites by cyanobacteria in association with the mass development of water blooms can lead to adverse impacts in aquatic ecosystems regarding the described teratogenicity of retinoids. Moreover, our finding that retinal can be non-enzymatically converted into more bioactive retinoids, also in water, and out of the cells, increases the environmental significance of this process.
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3
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Production and structural characterization of the cytochrome P450 enzymes in carotene ring hydroxylation. Methods Enzymol 2022; 671:223-241. [DOI: 10.1016/bs.mie.2022.03.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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4
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Alagoz Y, Mi J, Balakrishna A, Almarwaey L, Al-Babili S. Characterizing cytochrome P450 enzymes involved in plant apocarotenoid metabolism by using an engineered yeast system. Methods Enzymol 2022; 671:527-552. [DOI: 10.1016/bs.mie.2022.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Zheng S, Guo J, Cheng F, Gao Z, Du L, Meng C, Li S, Zhang X. Cytochrome P450s in algae: Bioactive natural product biosynthesis and light-driven bioproduction. Acta Pharm Sin B 2022; 12:2832-2844. [PMID: 35755277 PMCID: PMC9214053 DOI: 10.1016/j.apsb.2022.01.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 01/05/2022] [Accepted: 01/17/2022] [Indexed: 11/16/2022] Open
Abstract
Algae are a large group of photosynthetic organisms responsible for approximately half of the earth's total photosynthesis. In addition to their fundamental ecological roles as oxygen producers and as the food base for almost all aquatic life, algae are also a rich source of bioactive natural products, including several clinical drugs. Cytochrome P450 enzymes (P450s) are a superfamily of biocatalysts that are extensively involved in natural product biosynthesis by mediating various types of reactions. In the post-genome era, a growing number of P450 genes have been discovered from algae, indicating their important roles in algal life-cycle. However, the functional studies of algal P450s remain limited. Benefitting from the recent technical advances in algae cultivation and genetic manipulation, the researches on P450s in algal natural product biosynthesis have been approaching to a new stage. Moreover, some photoautotrophic algae have been developed into “photo-bioreactors” for heterologous P450s to produce high-value added pharmaceuticals and chemicals in a carbon-neutral or carbon-negative manner. Here, we comprehensively review these advances of P450 studies in algae from 2000 to 2021.
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Affiliation(s)
- Shanmin Zheng
- School of Life Sciences, Shandong University of Technology, Zibo 255000, China
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Jiawei Guo
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Fangyuan Cheng
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Zhengquan Gao
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China
| | - Lei Du
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Chunxiao Meng
- School of Life Sciences, Shandong University of Technology, Zibo 255000, China
- Corresponding authors. Tel./fax: +86 532 58632496.
| | - Shengying Li
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
- Corresponding authors. Tel./fax: +86 532 58632496.
| | - Xingwang Zhang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
- Corresponding authors. Tel./fax: +86 532 58632496.
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6
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Dermauw W, Van Leeuwen T, Feyereisen R. Diversity and evolution of the P450 family in arthropods. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2020; 127:103490. [PMID: 33169702 DOI: 10.1016/j.ibmb.2020.103490] [Citation(s) in RCA: 89] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 10/09/2020] [Accepted: 10/09/2020] [Indexed: 05/13/2023]
Abstract
The P450 family (CYP genes) of arthropods encodes diverse enzymes involved in the metabolism of foreign compounds and in essential endocrine or ecophysiological functions. The P450 sequences (CYPome) from 40 arthropod species were manually curated, including 31 complete CYPomes, and a maximum likelihood phylogeny of nearly 3000 sequences is presented. Arthropod CYPomes are assembled from members of six CYP clans of variable size, the CYP2, CYP3, CYP4 and mitochondrial clans, as well as the CYP20 and CYP16 clans that are not found in Neoptera. CYPome sizes vary from two dozen genes in some parasitic species to over 200 in species as diverse as collembolans or ticks. CYPomes are comprised of few CYP families with many genes and many CYP families with few genes, and this distribution is the result of dynamic birth and death processes. Lineage-specific expansions or blooms are found throughout the phylogeny and often result in genomic clusters that appear to form a reservoir of catalytic diversity maintained as heritable units. Among the many P450s with physiological functions, six CYP families are involved in ecdysteroid metabolism. However, five so-called Halloween genes are not universally represented and do not constitute the unique pathway of ecdysteroid biosynthesis. The diversity of arthropod CYPomes has only partially been uncovered to date and many P450s with physiological functions regulating the synthesis and degradation of endogenous signal molecules (including ecdysteroids) and semiochemicals (including pheromones and defense chemicals) remain to be discovered. Sequence diversity of arthropod P450s is extreme, and P450 sequences lacking the universally conserved Cys ligand to the heme have evolved several times. A better understanding of P450 evolution is needed to discern the relative contributions of stochastic processes and adaptive processes in shaping the size and diversity of CYPomes.
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Affiliation(s)
- Wannes Dermauw
- Laboratory of Agrozoology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | - Thomas Van Leeuwen
- Laboratory of Agrozoology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | - René Feyereisen
- Laboratory of Agrozoology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium; Department of Plant and Environmental Sciences, University of Copenhagen, 40 Thorvaldsensvej, DK-1871, Frederiksberg C, Copenhagen, Denmark.
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Finnigan JD, Young C, Cook DJ, Charnock SJ, Black GW. Cytochromes P450 (P450s): A review of the class system with a focus on prokaryotic P450s. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2020; 122:289-320. [PMID: 32951814 DOI: 10.1016/bs.apcsb.2020.06.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Cytochromes P450 (P450s) are a large superfamily of heme-containing monooxygenases. P450s are found in all Kingdoms of life and exhibit incredible diversity, both at sequence level and also on a biochemical basis. In the majority of cases, P450s can be assigned into one of ten classes based on their associated redox partners, domain architecture and cellular localization. Prokaryotic P450s now represent a large diverse collection of annotated/known enzymes, of which many have great potential biocatalytic potential. The self-sufficient P450 classes (Class VII/VIII) have been explored significantly over the past decade, with many annotated and biochemically characterized members. It is clear that the prokaryotic P450 world is expanding rapidly, as the number of published genomes and metagenome studies increases, and more P450 families are identified and annotated (CYP families).
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Affiliation(s)
| | - Carl Young
- Prozomix Limited, Haltwhistle, Northumberland, United Kingdom
| | - Darren J Cook
- Prozomix Limited, Haltwhistle, Northumberland, United Kingdom
| | | | - Gary W Black
- Hub for Biotechnology in the Built Environment, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, United Kingdom
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Abstract
Two cytochrome P450 enzymes, CYP97A3 and CYP97C1, catalyze hydroxylations of the β- and ε-rings of α-carotene to produce lutein. Chirality is introduced at the C-3 atom of both rings, and the reactions are both pro-3R-stereospecific. We determined the crystal structures of CYP97A3 in substrate-free and complex forms with a nonnatural substrate and the structure of CYP97C1 in a detergent-bound form. The structures of CYP97A3 in different states show the substrate channel and the structure of CYP97C1 bound with octylthioglucoside confirms the binding site for the carotenoid substrate. Biochemical assays confirm that the ferredoxin-NADP+ reductase (FNR)-ferredoxin pair is used as the redox partner. Details of the pro-3R stereospecificity are revealed in the retinal-bound CYP97A3 structure. Further analysis indicates that the CYP97B clan bears similarity to the β-ring-specific CYP97A clan. Overall, our research describes the molecular basis for the last steps of lutein biosynthesis.
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von Lintig J, Moon J, Babino D. Molecular components affecting ocular carotenoid and retinoid homeostasis. Prog Retin Eye Res 2020; 80:100864. [PMID: 32339666 DOI: 10.1016/j.preteyeres.2020.100864] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 04/13/2020] [Accepted: 04/17/2020] [Indexed: 12/15/2022]
Abstract
The photochemistry of vision employs opsins and geometric isomerization of their covalently bound retinylidine chromophores. In different animal classes, these light receptors associate with distinct G proteins that either hyperpolarize or depolarize photoreceptor membranes. Vertebrates also use the acidic form of chromophore, retinoic acid, as the ligand of nuclear hormone receptors that orchestrate eye development. To establish and sustain these processes, animals must acquire carotenoids from the diet, transport them, and metabolize them to chromophore and retinoic acid. The understanding of carotenoid metabolism, however, lagged behind our knowledge about the biology of their receptor molecules. In the past decades, much progress has been made in identifying the genes encoding proteins that mediate the transport and enzymatic transformations of carotenoids and their retinoid metabolites. Comparative analysis in different animal classes revealed how evolutionary tinkering with a limited number of genes evolved different biochemical strategies to supply photoreceptors with chromophore. Mutations in these genes impair carotenoid metabolism and induce various ocular pathologies. This review summarizes this advancement and introduces the involved proteins, including the homeostatic regulation of their activities.
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Affiliation(s)
- Johannes von Lintig
- Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, OH, USA.
| | - Jean Moon
- Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Darwin Babino
- Department of Ophthalmology, School of Medicine, University of Washington, Seattle, WA, USA
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Khumalo MJ, Nzuza N, Padayachee T, Chen W, Yu JH, Nelson DR, Syed K. Comprehensive Analyses of Cytochrome P450 Monooxygenases and Secondary Metabolite Biosynthetic Gene Clusters in Cyanobacteria. Int J Mol Sci 2020; 21:ijms21020656. [PMID: 31963856 PMCID: PMC7014017 DOI: 10.3390/ijms21020656] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Revised: 01/13/2020] [Accepted: 01/15/2020] [Indexed: 12/12/2022] Open
Abstract
The prokaryotic phylum Cyanobacteria are some of the oldest known photosynthetic organisms responsible for the oxygenation of the earth. Cyanobacterial species have been recognised as a prosperous source of bioactive secondary metabolites with antibacterial, antiviral, antifungal and/or anticancer activities. Cytochrome P450 monooxygenases (CYPs/P450s) contribute to the production and diversity of various secondary metabolites. To better understand the metabolic potential of cyanobacterial species, we have carried out comprehensive analyses of P450s, predicted secondary metabolite biosynthetic gene clusters (BGCs), and P450s located in secondary metabolite BGCs. Analysis of the genomes of 114 cyanobacterial species identified 341 P450s in 88 species, belonging to 36 families and 79 subfamilies. In total, 770 secondary metabolite BGCs were found in 103 cyanobacterial species. Only 8% of P450s were found to be part of BGCs. Comparative analyses with other bacteria Bacillus, Streptomyces and mycobacterial species have revealed a lower number of P450s and BGCs and a percentage of P450s forming part of BGCs in cyanobacterial species. A mathematical formula presented in this study revealed that cyanobacterial species have the highest gene-cluster diversity percentage compared to Bacillus and mycobacterial species, indicating that these diverse gene clusters are destined to produce different types of secondary metabolites. The study provides fundamental knowledge of P450s and those associated with secondary metabolism in cyanobacterial species, which may illuminate their value for the pharmaceutical and cosmetics industries.
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Affiliation(s)
- Makhosazana Jabulile Khumalo
- Department of Biochemistry and Microbiology, Faculty of Science and Agriculture, University of Zululand, KwaDlangezwa 3886, South Africa; (M.J.K.); (N.N.); (T.P.)
| | - Nomfundo Nzuza
- Department of Biochemistry and Microbiology, Faculty of Science and Agriculture, University of Zululand, KwaDlangezwa 3886, South Africa; (M.J.K.); (N.N.); (T.P.)
| | - Tiara Padayachee
- Department of Biochemistry and Microbiology, Faculty of Science and Agriculture, University of Zululand, KwaDlangezwa 3886, South Africa; (M.J.K.); (N.N.); (T.P.)
| | - Wanping Chen
- Department of Molecular Microbiology and Genetics, University of Göttingen, 37077 Göttingen, Germany;
| | - Jae-Hyuk Yu
- Department of Bacteriology, University of Wisconsin-Madison, 3155 MSB, 1550 Linden Drive, Madison, WI 53706, USA;
- Department of Systems Biotechnology, Konkuk University, Seoul 05029, Korea
| | - David R. Nelson
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, TN 38163, USA
- Correspondence: (D.R.N.); (K.S.)
| | - Khajamohiddin Syed
- Department of Biochemistry and Microbiology, Faculty of Science and Agriculture, University of Zululand, KwaDlangezwa 3886, South Africa; (M.J.K.); (N.N.); (T.P.)
- Correspondence: (D.R.N.); (K.S.)
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Isoherranen N, Zhong G. Biochemical and physiological importance of the CYP26 retinoic acid hydroxylases. Pharmacol Ther 2019; 204:107400. [PMID: 31419517 PMCID: PMC6881548 DOI: 10.1016/j.pharmthera.2019.107400] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 08/06/2019] [Indexed: 12/19/2022]
Abstract
The Cytochrome P450 (CYP) family 26 enzymes contribute to retinoic acid (RA) metabolism and homeostasis in humans, mammals and other chordates. The three CYP26 family enzymes, CYP26A1, CYP26B1 and CYP26C1 have all been shown to metabolize all-trans-retinoic acid (atRA) it's 9-cisRA and 13-cisRA isomers and primary metabolites 4-OH-RA and 4-oxo-RA with high efficiency. While no crystal structures of CYP26 enzymes are available, the binding of various ligands has been extensively explored via homology modeling. All three CYP26 enzymes are inducible by treatment with atRA in various prenatal and postnatal tissues and cell types. However, current literature shows that in addition to regulation by atRA, CYP26 enzyme expression is also regulated by other endogenous processes and inflammatory cytokines. In humans and in animal models the expression patterns of CYP26 enzymes have been shown to be tissue and cell type specific, and the expression of the CYP26 enzymes is believed to regulate the formation of critical atRA concentration gradients in various tissue types. Yet, very little data exists on direct disease associations of altered CYP26 expression or activity. Nevertheless, data is emerging describing a variety of human genetic variations in the CYP26 enzymes that are associated with different pathologies. Interestingly, some of these genetic variants result in increased activity of the CYP26 enzymes potentially leading to complex gene-environment interactions due to variability in dietary intake of retinoids. This review highlights the current knowledge of structure-function of CYP26 enzymes and focuses on their role in human retinoid metabolism in different tissues.
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Affiliation(s)
- Nina Isoherranen
- Department of Pharmaceutics, School of Pharmacy, University of Washington, Seattle, WA, USA.
| | - Guo Zhong
- Department of Pharmaceutics, School of Pharmacy, University of Washington, Seattle, WA, USA
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Miles JA, Machattou P, Nevin-Jones D, Webb ME, Millard A, Scanlan DJ, Taylor PC. Identification of a cyanobacterial aldehyde dehydrogenase that produces retinoic acid in vitro. Biochem Biophys Res Commun 2019; 510:27-34. [DOI: 10.1016/j.bbrc.2018.12.171] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 12/27/2018] [Indexed: 11/15/2022]
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Deletion of sll1541 in Synechocystis sp. Strain PCC 6803 Allows Formation of a Far-Red-Shifted holo-Proteorhodopsin In Vivo. Appl Environ Microbiol 2018; 84:AEM.02435-17. [PMID: 29475867 DOI: 10.1128/aem.02435-17] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 02/08/2018] [Indexed: 12/25/2022] Open
Abstract
In many pro- and eukaryotes, a retinal-based proton pump equips the cell to drive ATP synthesis with (sun)light. Such pumps, therefore, have been proposed as a plug-in for cyanobacteria to artificially increase the efficiency of oxygenic photosynthesis. However, little information on the metabolism of retinal, their chromophore, is available for these organisms. We have studied the in vivo roles of five genes (sll1541, slr1648, slr0091, slr1192, and slr0574) potentially involved in retinal metabolism in Synechocystis sp. strain PCC 6803. With a gene deletion approach, we have shown that Synechocystis apo-carotenoid-15,15-oxygenase (SynACO), encoded by gene sll1541, is an indispensable enzyme for retinal synthesis in Synechocystis, presumably via asymmetric cleavage of β-apo-carotenal. The second carotenoid oxygenase (SynDiox2), encoded by gene slr1648, competes with SynACO for substrate(s) but only measurably contributes to retinal biosynthesis in stationary phase via an as-yet-unknown mechanism. In vivo degradation of retinal may proceed through spontaneous chemical oxidation and via enzyme-catalyzed processes. Deletion of gene slr0574 (encoding CYP120A1), but not of slr0091 or of slr1192, causes an increase (relative to the level in wild-type Synechocystis) in the retinal content in both the linear and stationary growth phases. These results suggest that CYP120A1 does contribute to retinal degradation. Preliminary data obtained using 13C-labeled retinal suggest that conversion to retinol and retinoic acid and subsequent further oxidation also play a role. Deletion of sll1541 leads to deficiency in retinal synthesis and allows the in vivo reconstitution of far-red-absorbing holo-proteorhodopsin with exogenous retinal analogues, as demonstrated here for all-trans 3,4-dehydroretinal and 3-methylamino-16-nor-1,2,3,4-didehydroretinal.IMPORTANCE Retinal is formed by many cyanobacteria and has a critical role in most forms of life for processes such as photoreception, growth, and stress survival. However, the metabolic pathways in cyanobacteria for synthesis and degradation of retinal are poorly understood. In this paper we identify genes involved in its synthesis, characterize their role, and provide an initial characterization of the pathway of its degradation. This led to the identification of sll1541 (encoding SynACO) as the essential gene for retinal synthesis. Multiple pathways for retinal degradation presumably exist. These results have allowed us to construct a strain that expresses a light-dependent proton pump with an action spectrum extending beyond 700 nm. The availability of this strain will be important for further work aimed at increasing the overall efficiency of oxygenic photosynthesis.
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Loeschcke A, Dienst D, Wewer V, Hage-Hülsmann J, Dietsch M, Kranz-Finger S, Hüren V, Metzger S, Urlacher VB, Gigolashvili T, Kopriva S, Axmann IM, Drepper T, Jaeger KE. The photosynthetic bacteria Rhodobacter capsulatus and Synechocystis sp. PCC 6803 as new hosts for cyclic plant triterpene biosynthesis. PLoS One 2017; 12:e0189816. [PMID: 29281679 PMCID: PMC5744966 DOI: 10.1371/journal.pone.0189816] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 12/01/2017] [Indexed: 11/18/2022] Open
Abstract
Cyclic triterpenes constitute one of the most diverse groups of plant natural products. Besides the intriguing biochemistry of their biosynthetic pathways, plant triterpenes exhibit versatile bioactivities, including antimicrobial effects against plant and human pathogens. While prokaryotes have been extensively used for the heterologous production of other classes of terpenes, the synthesis of cyclic triterpenes, which inherently includes the two-step catalytic formation of the universal linear precursor 2,3-oxidosqualene, is still a major challenge. We thus explored the suitability of the metabolically versatile photosynthetic α-proteobacterium Rhodobacter capsulatus SB1003 and cyanobacterium Synechocystis sp. PCC 6803 as alternative hosts for biosynthesis of cyclic plant triterpenes. Therefore, 2,3-oxidosqualene production was implemented and subsequently combined with different cyclization reactions catalyzed by the representative oxidosqualene cyclases CAS1 (cycloartenol synthase), LUP1 (lupeol synthase), THAS1 (thalianol synthase) and MRN1 (marneral synthase) derived from model plant Arabidopsis thaliana. While successful accumulation of 2,3-oxidosqualene could be detected by LC-MS analysis in both hosts, cyclase expression resulted in differential production profiles. CAS1 catalyzed conversion to only cycloartenol, but expression of LUP1 yielded lupeol and a triterpenoid matching an oxidation product of lupeol, in both hosts. In contrast, THAS1 expression did not lead to cyclic product formation in either host, whereas MRN1-dependent production of marnerol and hydroxymarnerol was observed in Synechocystis but not in R. capsulatus. Our findings thus indicate that 2,3-oxidosqualene cyclization in heterologous phototrophic bacteria is basically feasible but efficient conversion depends on both the respective cyclase enzyme and individual host properties. Therefore, photosynthetic α-proteo- and cyanobacteria are promising alternative candidates for providing new bacterial access to the broad class of triterpenes for biotechnological applications.
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Affiliation(s)
- Anita Loeschcke
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, Forschungszentrum Jülich, Jülich, Germany
- Cluster of Excellence on Plant Sciences (CEPLAS)
| | - Dennis Dienst
- Cluster of Excellence on Plant Sciences (CEPLAS)
- Institute for Synthetic Microbiology, Department of Biology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Vera Wewer
- Cluster of Excellence on Plant Sciences (CEPLAS)
- MS Platform, Department of Biology, University of Cologne, Cologne, Germany
| | - Jennifer Hage-Hülsmann
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, Forschungszentrum Jülich, Jülich, Germany
- Cluster of Excellence on Plant Sciences (CEPLAS)
| | - Maximilian Dietsch
- Cluster of Excellence on Plant Sciences (CEPLAS)
- Institute for Synthetic Microbiology, Department of Biology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Sarah Kranz-Finger
- Cluster of Excellence on Plant Sciences (CEPLAS)
- Institute of Biochemistry II, Department of Chemistry, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Vanessa Hüren
- Cluster of Excellence on Plant Sciences (CEPLAS)
- Institute for Synthetic Microbiology, Department of Biology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Sabine Metzger
- Cluster of Excellence on Plant Sciences (CEPLAS)
- MS Platform, Department of Biology, University of Cologne, Cologne, Germany
| | - Vlada B. Urlacher
- Cluster of Excellence on Plant Sciences (CEPLAS)
- Institute of Biochemistry II, Department of Chemistry, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Tamara Gigolashvili
- Cluster of Excellence on Plant Sciences (CEPLAS)
- Botanical Institute, University of Cologne, Cologne, Germany
| | - Stanislav Kopriva
- Cluster of Excellence on Plant Sciences (CEPLAS)
- Botanical Institute, University of Cologne, Cologne, Germany
| | - Ilka M. Axmann
- Cluster of Excellence on Plant Sciences (CEPLAS)
- Institute for Synthetic Microbiology, Department of Biology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- * E-mail: (IMA); (TD)
| | - Thomas Drepper
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, Forschungszentrum Jülich, Jülich, Germany
- Cluster of Excellence on Plant Sciences (CEPLAS)
- * E-mail: (IMA); (TD)
| | - Karl-Erich Jaeger
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, Forschungszentrum Jülich, Jülich, Germany
- Cluster of Excellence on Plant Sciences (CEPLAS)
- Institute of Bio- and Geosciences (IBG-1), Forschungszentrum Jülich, Jülich, Germany
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15
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Chen Q, van der Steen JB, Dekker HL, Ganapathy S, de Grip WJ, Hellingwerf KJ. Expression of holo-proteorhodopsin in Synechocystis sp. PCC 6803. Metab Eng 2016; 35:83-94. [PMID: 26869136 DOI: 10.1016/j.ymben.2016.02.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 01/11/2016] [Accepted: 02/01/2016] [Indexed: 01/15/2023]
Abstract
Retinal-based photosynthesis may contribute to the free energy conversion needed for growth of an organism carrying out oxygenic photosynthesis, like a cyanobacterium. After optimization, this may even enhance the overall efficiency of phototrophic growth of such organisms in sustainability applications. As a first step towards this, we here report on functional expression of the archetype proteorhodopsin in Synechocystis sp. PCC 6803. Upon use of the moderate-strength psbA2 promoter, holo-proteorhodopsin is expressed in this cyanobacterium, at a level of up to 10(5) molecules per cell, presumably in a hexameric quaternary structure, and with approximately equal distribution (on a protein-content basis) over the thylakoid and the cytoplasmic membrane fraction. These results also demonstrate that Synechocystis sp. PCC 6803 has the capacity to synthesize all-trans-retinal. Expressing a substantial amount of a heterologous opsin membrane protein causes a substantial growth retardation Synechocystis, as is clear from a strain expressing PROPS, a non-pumping mutant derivative of proteorhodopsin. Relative to this latter strain, proteorhodopsin expression, however, measurably stimulates its growth.
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Affiliation(s)
- Que Chen
- Molecular Microbial Physiology, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Jeroen B van der Steen
- Molecular Microbial Physiology, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Henk L Dekker
- Mass Spectrometry of Biomacromolecules, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Srividya Ganapathy
- Biophysical Organic Chemistry, Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands
| | - Willem J de Grip
- Biophysical Organic Chemistry, Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands
| | - Klaas J Hellingwerf
- Molecular Microbial Physiology, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands.
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16
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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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17
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Millard A, Scanlan DJ, Gallagher C, Marsh A, Taylor PC. Unexpected evolutionary proximity of eukaryotic and cyanobacterial enzymes responsible for biosynthesis of retinoic acid and its oxidation. MOLECULAR BIOSYSTEMS 2014; 10:380-3. [DOI: 10.1039/c3mb70447e] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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18
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Trautmann D, Beyer P, Al-Babili S. The ORF slr0091 of Synechocystis sp. PCC6803 encodes a high-light induced aldehyde dehydrogenase converting apocarotenals and alkanals. FEBS J 2013; 280:3685-96. [PMID: 23734995 DOI: 10.1111/febs.12361] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2013] [Revised: 05/26/2013] [Accepted: 05/28/2013] [Indexed: 11/30/2022]
Abstract
Oxidative cleavage of carotenoids and peroxidation of lipids lead to apocarotenals and aliphatic aldehydes called alkanals, which react with vitally important compounds, promoting cytotoxicity. Although many enzymes have been reported to deactivate alkanals by converting them into fatty acids, little is known about the mechanisms used to detoxify apocarotenals or the enzymes acting on them. Cyanobacteria and other photosynthetic organisms must cope with both classes of aldehydes. Here we report that the Synechocystis enzyme SynAlh1, encoded by the ORF slr0091, is an aldehyde dehydrogenase that mediates oxidation of both apocarotenals and alkanals into the corresponding acids. Using a crude lysate of SynAlh1-expressing Escherichia coli cells, we show that SynAlh1 converts a wide range of apocarotenals and alkanals, with a preference for apocarotenals with defined chain lengths. As suggested by in vitro incubations and using engineered retinal-forming E. coli cells, we found that retinal is not a substrate for SynAlh1, making involvement in Synechocystis retinoid metabolism unlikely. The transcript level of SynAlh1 is induced by high light and cold treatment, indicating a role in the stress response, and the corresponding gene is a constituent of a stress-related operon. The assumptions regarding the function of SynAlh are further supported by the surprisingly high homology to human and plant aldehyde dehydrogenase that have been assigned to aldehyde detoxification. SynAlh1 is the first aldehyde dehydrogenase that has been shown to form both apocarotenoic and fatty acids. This dual function suggests that its eukaryotic homologs may also be involved in apocarotenal metabolism, a function that has not been considered so far.
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Affiliation(s)
- Danika Trautmann
- Faculty of Biology, Albert-Ludwigs University of Freiburg, Freiburg, Germany
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19
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Abstract
Deformed amphibians have been observed in eutrophic habitats, and some clues point to the retinoic acids (RAs) or RA mimics. However, RAs are generally thought of as vertebrate-specific hormones, and there was no evidence that RAs exist in cyanobacteria or algae blooms. By analyzing RAs and their analogs 4-oxo-RAs in natural cyanobacteria blooms and cultures of cyanobacteria and algae, we showed that cyanobacteria blooms could produce RAs, which were powerful animal teratogens. Intracellular RAs and 4-oxo-RAs with concentrations between 0.4 and 4.2 × 10(2) ng/L were detected in all bloom materials, and extracellular concentrations measured in water from Taihu Lake, China, were as great as 2.0 × 10 ng/L, which might pose a risk to wildlife through chronic exposure. Further examination of 39 cyanobacteria and algae species revealed that 32 species could produce RAs and 4-oxo-RAs (1.6-1.4 × 10(3) ng/g dry weight), and the dominant cyanobacteria species in Taihu Lake, Microcystis flos-aquae and Microcystis aeruginosa, produced high amounts of RAs and 4-oxo-RAs with concentrations of 1.4 × 10(3) and 3.7 × 10(2) ng/g dry weight, respectively. Most genera of cyanobacteria that could produce RAs and 4-oxo-RAs, such as Microcystis, Anabaena, and Aphanizomenon, often occur dominantly in blooms. Production of RAs and 4-oxo-RAs by cyanobacteria was associated with species, origin location, and growth stage. These results represent a conclusive demonstration of endogenous production of RAs in freshwater cyanobacteria blooms. The observation of teratogenic RAs in cyanobacteria is evolutionarily and ecologically significant because RAs are vertebrate-specific hormones, and cyanobacteria form extensive and highly visible blooms in many aquatic ecosystems.
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20
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Gotoh O. Evolution of Cytochrome P450 Genes from the Viewpoint of Genome Informatics. Biol Pharm Bull 2012; 35:812-7. [DOI: 10.1248/bpb.35.812] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Osamu Gotoh
- Department of Intelligence Science and Technology, Graduate School of Informatics, Kyoto University
- Computational Biology Research Center (CBRC), National Institute of Advanced Industrial Science and Technology
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21
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Topletz AR, Thatcher JE, Zelter A, Lutz JD, Tay S, Nelson WL, Isoherranen N. Comparison of the function and expression of CYP26A1 and CYP26B1, the two retinoic acid hydroxylases. Biochem Pharmacol 2011; 83:149-63. [PMID: 22020119 DOI: 10.1016/j.bcp.2011.10.007] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2011] [Revised: 10/06/2011] [Accepted: 10/07/2011] [Indexed: 10/16/2022]
Abstract
All-trans-retinoic acid (atRA) is an important signaling molecule in all chordates. The cytochrome P450 enzymes CYP26 are believed to partially regulate cellular concentrations of atRA via oxidative metabolism and hence affect retinoid homeostasis and signaling. CYP26A1 and CYP26B1 are atRA hydroxylases that catalyze formation of similar metabolites in cell systems. However, they have only 40% sequence similarity suggesting differences between the two enzymes. The aim of this study was to determine whether CYP26A1 and CYP26B1 have similar catalytic activity, form different metabolites from atRA and are expressed in different tissues in adults. The mRNA expression of CYP26A1 and CYP26B1 correlated between human tissues except for human cerebellum in which CYP26B1 was the predominant CYP26 and liver in which CYP26A1 dominated. Quantification of CYP26A1 and CYP26B1 protein in human tissues was in agreement with the mRNA expression and showed correlation between the two isoforms. Qualitatively, recombinant CYP26A1 and CYP26B1 formed the same primary and sequential metabolites from atRA. Quantitatively, CYP26B1 had a lower K(m) (19nM) and V(max) (0.8 pmol/min/pmol) than CYP26A1 (K(m)=50 nM and V(max)=10 pmol/min/pmol) for formation of 4-OH-RA. The major atRA metabolites 4-OH-RA, 18-OH-RA and 4-oxo-RA were all substrates of CYP26A1 and CYP26B1, and CYP26A1 had a 2-10-fold higher catalytic activity towards all substrates tested. This study shows that CYP26A1 and CYP26B1 are qualitatively similar RA hydroxylases with overlapping expression profiles. CYP26A1 has higher catalytic activity than CYP26B1 and seems to be responsible for metabolism of atRA in tissues that function as a barrier for atRA exposure.
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Affiliation(s)
- Ariel R Topletz
- Department of Pharmaceutics, University of Washington, Seattle, United States
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22
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Thatcher JE, Buttrick B, Shaffer SA, Shimshoni JA, Goodlett DR, Nelson WL, Isoherranen N. Substrate specificity and ligand interactions of CYP26A1, the human liver retinoic acid hydroxylase. Mol Pharmacol 2011; 80:228-39. [PMID: 21521770 DOI: 10.1124/mol.111.072413] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
All-trans-retinoic acid (atRA) is the active metabolite of vitamin A. atRA is also used as a drug, and synthetic atRA analogs and inhibitors of retinoic acid (RA) metabolism have been developed. The hepatic clearance of atRA is mediated primarily by CYP26A1, but design of CYP26A1 inhibitors is hindered by lack of information on CYP26A1 structure and structure-activity relationships of its ligands. The aim of this study was to identify the primary metabolites of atRA formed by CYP26A1 and to characterize the ligand selectivity and ligand interactions of CYP26A1. On the basis of high-resolution tandem mass spectrometry data, four metabolites formed from atRA by CYP26A1 were identified as 4-OH-RA, 4-oxo-RA, 16-OH-RA and 18-OH-RA. 9-cis-RA and 13-cis-RA were also substrates of CYP26A1. Forty-two compounds with diverse structural properties were tested for CYP26A1 inhibition using 9-cis-RA as a probe, and IC(50) values for 10 inhibitors were determined. The imidazole- and triazole-containing inhibitors [S-(R*,R*)]-N-[4-[2-(dimethylamino)-1-(1H-imidazole-1-yl)propyl]-phenyl]2-benzothiazolamine (R116010) and (R)-N-[4-[2-ethyl-1-(1H-1,2,4-triazol-1-yl)butyl]phenyl]-2-benzothiazolamine (R115866) were the most potent inhibitors of CYP26A1 with IC(50) values of 4.3 and 5.1 nM, respectively. Liarozole and ketoconazole were significantly less potent with IC(50) values of 2100 and 550 nM, respectively. The retinoic acid receptor (RAR) γ agonist CD1530 was as potent an inhibitor of CYP26A1 as ketoconazole with an IC(50) of 530 nM, whereas the RARα and RARβ agonists tested did not significantly inhibit CYP26A1. The pan-RAR agonist 4-[(E)-2-(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenyl)-1-propenyl]benzoic acid and the peroxisome proliferator-activated receptor ligands rosiglitazone and pioglitazone inhibited CYP26A1 with IC(50) values of 3.7, 4.2, and 8.6 μM, respectively. These data demonstrate that CYP26A1 has high ligand selectivity but accepts structurally related nuclear receptor agonists as inhibitors.
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Affiliation(s)
- Jayne E Thatcher
- Department of Pharmaceutics, Box 357610, University of Washington, Seattle, WA 98195, USA
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23
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Walter MH, Floss DS, Strack D. Apocarotenoids: hormones, mycorrhizal metabolites and aroma volatiles. PLANTA 2010; 232:1-17. [PMID: 20396903 DOI: 10.1007/s00425-010-1156-3] [Citation(s) in RCA: 141] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2010] [Accepted: 03/12/2010] [Indexed: 05/18/2023]
Abstract
Apocarotenoids are tailored from carotenoids by oxidative enzymes [carotenoid cleavage oxygenases (CCOs)], cleaving specific double bonds of the polyene chain. The cleavage products can act as hormones, signaling compounds, chromophores and scent/aroma constituents. Recent advances were the identification of strigolactones as apocarotenoids and the description of their novel role as shoot branching inhibitor hormones. Strigolactones are also involved in plant signaling to both harmful (parasitic weeds) and beneficial [arbuscular mycorrhizal (AM) fungi] rhizosphere residents. This review describes the progress in the characterization of CCOs, termed CCDs and NCEDs, in plants. It highlights the importance of sequential cleavage reactions of C(40) carotenoid precursors, the apocarotenoid cleavage oxygenase (ACO) nature of several CCOs and the topic of compartmentation. Work on the biosynthesis of abundant C(13) cyclohexenone and C(14) mycorradicin apocarotenoids in mycorrhizal roots has revealed a new role of CCD1 as an ACO of C(27) apocarotenoid intermediates, following their predicted export from plastid to cytosol. Manipulation of the AM-induced apocarotenoid pathway further suggests novel roles of C(13) apocarotenoids in controlling arbuscule turnover in the AM symbiosis. CCD7 has been established as a biosynthetic crosspoint, controlling both strigolactone and AM-induced C(13) apocarotenoid biosynthesis. Interdependence of the two apocarotenoid pathways may thus play a role in AM-mediated reduction of parasitic weed infestations. Potential scenarios of C(13) scent/aroma volatile biogenesis are discussed, including the novel mechanism revealed from mycorrhizal roots. The recent progress in apocarotenoid research opens up new perspectives for fundamental work, but has also great application potential for the horticulture, food and fragrance industries.
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Affiliation(s)
- Michael H Walter
- Abteilung Sekundärstoffwechsel, Leibniz-Institut für Pflanzenbiochemie, Halle (Saale), Germany.
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24
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Robert FO, Pandhal J, Wright PC. Exploiting cyanobacterial P450 pathways. Curr Opin Microbiol 2010; 13:301-6. [PMID: 20299274 DOI: 10.1016/j.mib.2010.02.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2010] [Revised: 02/22/2010] [Accepted: 02/23/2010] [Indexed: 10/19/2022]
Abstract
Cytochrome P450s are hemoprotein oxygenases involved in natural product synthetic pathways. Cyanobacteria are oxygenic photosynthetic microorganisms and are considered a rich source of natural products, and are now known to harbour P450s. A variety of cyanobacterial species have been found to contain multiple copies of P450s in their genomes, and over 100 have been predicted. Interestingly, some are membrane-bound as in eukaryotes, as opposed to cytoplasmic in bacteria. Furthermore, they can complement plant P450s and perform bioremediation of oil spills by the breakdown of alkanes. Functional expression of a selection Nostoc spp. P450s in Escherichia coli, with associated enzymes, has successfully produced the sesquiterpenes--germacradienol, germacrene and B-elemene, although others have failed for undetermined reasons.
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Affiliation(s)
- Faith O Robert
- ChELSI Institute, Department of Chemical and Process Engineering, The University of Sheffield, Mappin Street, S1 3JD, Sheffield, UK
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