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Lin YJ, Yao BT, Zhang Q, Feng YX, Xiang L. Biochemical insights into proline metabolism and its contribution to the endurant cell wall structure under metal stress. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 282:116725. [PMID: 39002377 DOI: 10.1016/j.ecoenv.2024.116725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 07/09/2024] [Accepted: 07/10/2024] [Indexed: 07/15/2024]
Abstract
The cell wall serves as the primary barrier against the entry of heavy metal ions into cells. However, excessive accumulation of heavy metals within plants can lead to alterations in the spatial structure and physical properties of the cell wall, thereby affecting the capacity of plants to capture heavy metals. Proline (Pro) is involved in the synthesis of the cell wall, modulating the stability and integrity of its structure. Extensins, core proteins that maintain the cell wall structure, are proline/hydroxyproline-rich glycoproteins that contain the characteristic sequence Ser-[Pro]3-5. They act as intermediates in the regulation of biological processes such as cell wall synthesis, assembly, and signal transduction, typically forming a network structure of cell wall proteins through cross-linking with pectin. This network is essential for the self-assembly expansion of the plant cell wall and plays an indispensable role in cell wall stress signal transduction through its interaction with intracellular signalling molecules. However, the mechanisms by which Pro affects the synthesis of cell wall structural proteins, cell wall assembly, and the sensing of cell wall stress under heavy metal stress remain unclear. This review, from the perspectives of biochemistry and molecular biology, comprehensively elaborates on the impact of Pro and Pro-rich proteins on the structure and function of the cell wall. These findings emphasize the mechanism by which Pro enhances the ability of the cell wall to capture heavy metals, providing new research ideas for the use of genetic engineering to manipulate cell wall synthesis and repair, thereby reducing the phytotoxicity of heavy metals.
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Affiliation(s)
- Yu-Juan Lin
- College of Environmental Science & Engineering, Guilin University of Technology, Guilin 541006, China; The Guangxi Key Laboratory of Theory and Technology for Environmental Pollution Control, Guilin University of Technology, Guilin 541006, China; Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst Area, Guilin University of Technology, Guilin 541006, China
| | - Ben-Tao Yao
- College of Environmental Science & Engineering, Guilin University of Technology, Guilin 541006, China
| | - Qin Zhang
- College of Environmental Science & Engineering, Guilin University of Technology, Guilin 541006, China; The Guangxi Key Laboratory of Theory and Technology for Environmental Pollution Control, Guilin University of Technology, Guilin 541006, China; Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst Area, Guilin University of Technology, Guilin 541006, China
| | - Yu-Xi Feng
- College of Environmental Science & Engineering, Guilin University of Technology, Guilin 541006, China; The Guangxi Key Laboratory of Theory and Technology for Environmental Pollution Control, Guilin University of Technology, Guilin 541006, China; Guangdong-Hong Kong Joint Laboratory for Carbon Neutrality, Jiangmen Laboratory of Carbon Science and Technology, Jiangmen, Guangdong Province 529199, China.
| | - Lei Xiang
- College of Life Science and Technology, Guangzhou, Jinan University 510632, China
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Elsherif DE, Safhi FA, Subudhi PK, Shaban AS, El-Esawy MA, Khalifa AM. Phytochemical Profiling and Bioactive Potential of Grape Seed Extract in Enhancing Salinity Tolerance of Vicia faba. PLANTS (BASEL, SWITZERLAND) 2024; 13:1596. [PMID: 38931028 PMCID: PMC11207552 DOI: 10.3390/plants13121596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2024] [Revised: 06/05/2024] [Accepted: 06/05/2024] [Indexed: 06/28/2024]
Abstract
Salinity stress poses a significant threat to crop productivity worldwide, necessitating effective mitigation strategies. This study investigated the phytochemical composition and potential of grape seed extract (GSE) to mitigate salinity stress effects on faba bean plants. GC-MS analysis revealed several bioactive components in GSE, predominantly fatty acids. GSE was rich in essential nutrients and possessed a high antioxidant capacity. After 14 days of germination, GSE was applied as a foliar spray at different concentrations (0, 2, 4, 6, and 8 g/L) to mitigate the negative effects of salt stress (150 mM NaCl) on faba bean plants. Foliar application of 2-8 g/L GSE significantly enhanced growth parameters such as shoot length, root length, fresh weight, and dry weight of salt-stressed bean plants compared to the control. The Fv/Fm ratio, indicating photosynthetic activity, also improved with GSE treatment under salinity stress compared to the control. GSE effectively alleviated the oxidative stress induced by salinity, reducing malondialdehyde, hydrogen peroxide, praline, and glycine betaine levels. Total soluble proteins, amino acids, and sugars were enhanced in GSE-treated, salt-stressed plants. GSE treatment under salinity stress modulated the total antioxidant capacity, antioxidant responses, and enzyme activities such as peroxidase, ascorbate peroxidase, and polyphenol oxidase compared to salt-stressed plants. Gene expression analysis revealed GSE (6 g/L) upregulated photosynthesis (chlorophyll a/b-binding protein of LHCII type 1-like (Lhcb1) and ribulose bisphosphate carboxylase large chain-like (RbcL)) and carbohydrate metabolism (cell wall invertase I (CWINV1) genes) while downregulating stress response genes (ornithine aminotransferase (OAT) and ethylene-responsive transcription factor 1 (ERF1)) in salt-stressed bean plants. The study demonstrates GSE's usefulness in mitigating salinity stress effects on bean plants by modulating growth, physiology, and gene expression patterns, highlighting its potential as a natural approach to enhance salt tolerance.
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Affiliation(s)
- Doaa E. Elsherif
- Botany Department, Faculty of Science, Tanta University, Tanta 31527, Egypt; (D.E.E.); (M.A.E.-E.)
| | - Fatmah A. Safhi
- Department of Biology, College of Science, Princess Nourah bint Abdulrahman University, Riyadh 11671, Saudi Arabia;
| | - Prasanta K. Subudhi
- School of Plant, Environmental, and Soil Sciences, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA;
| | - Abdelghany S. Shaban
- Botany and Microbiology Department, Faculty of Science (Boys), Al-Azhar University, Cairo 11884, Egypt
| | - Mai A. El-Esawy
- Botany Department, Faculty of Science, Tanta University, Tanta 31527, Egypt; (D.E.E.); (M.A.E.-E.)
| | - Asmaa M. Khalifa
- Botany and Microbiology Department, Faculty of Science, Al-Azhar University (Girls Branch), Cairo 11765, Egypt;
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Key J, Gispert S, Kandi AR, Heinz D, Hamann A, Osiewacz HD, Meierhofer D, Auburger G. CLPP-Null Eukaryotes with Excess Heme Biosynthesis Show Reduced L-arginine Levels, Probably via CLPX-Mediated OAT Activation. Biomolecules 2024; 14:241. [PMID: 38397478 PMCID: PMC10886707 DOI: 10.3390/biom14020241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 02/12/2024] [Accepted: 02/16/2024] [Indexed: 02/25/2024] Open
Abstract
The serine peptidase CLPP is conserved among bacteria, chloroplasts, and mitochondria. In humans and mice, its loss causes Perrault syndrome, which presents with growth deficits, infertility, deafness, and ataxia. In the filamentous fungus Podospora anserina, CLPP loss leads to longevity. CLPP substrates are selected by CLPX, an AAA+ unfoldase. CLPX is known to target delta-aminolevulinic acid synthase (ALAS) to promote pyridoxal phosphate (PLP) binding. CLPX may also influence cofactor association with other enzymes. Here, the evaluation of P. anserina metabolomics highlighted a reduction in arginine/histidine levels. In Mus musculus cerebellum, reductions in arginine/histidine and citrulline occurred with a concomitant accumulation of the heme precursor protoporphyrin IX. This suggests that the increased biosynthesis of 5-carbon (C5) chain deltaALA consumes not only C4 succinyl-CoA and C1 glycine but also specific C5 delta amino acids. As enzymes responsible for these effects, the elevated abundance of CLPX and ALAS is paralleled by increased OAT (PLP-dependent, ornithine delta-aminotransferase) levels. Possibly as a consequence of altered C1 metabolism, the proteome profiles of P. anserina CLPP-null cells showed strong accumulation of a methyltransferase and two mitoribosomal large subunit factors. The reduced histidine levels may explain the previously observed metal interaction problems. As the main nitrogen-storing metabolite, a deficiency in arginine would affect the urea cycle and polyamine synthesis. Supplementation of arginine and histidine might rescue the growth deficits of CLPP-mutant patients.
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Affiliation(s)
- Jana Key
- Goethe University Frankfurt, University Hospital, Clinic of Neurology, Experimental Neurology, Heinrich Hoffmann Str. 7, 60590 Frankfurt am Main, Germany; (J.K.); (S.G.); (A.R.K.)
| | - Suzana Gispert
- Goethe University Frankfurt, University Hospital, Clinic of Neurology, Experimental Neurology, Heinrich Hoffmann Str. 7, 60590 Frankfurt am Main, Germany; (J.K.); (S.G.); (A.R.K.)
| | - Arvind Reddy Kandi
- Goethe University Frankfurt, University Hospital, Clinic of Neurology, Experimental Neurology, Heinrich Hoffmann Str. 7, 60590 Frankfurt am Main, Germany; (J.K.); (S.G.); (A.R.K.)
| | - Daniela Heinz
- Institute of Molecular Biosciences, Faculty of Biosciences, Goethe-University Frankfurt, 60438 Frankfurt am Main, Germany; (D.H.); (A.H.); (H.D.O.)
| | - Andrea Hamann
- Institute of Molecular Biosciences, Faculty of Biosciences, Goethe-University Frankfurt, 60438 Frankfurt am Main, Germany; (D.H.); (A.H.); (H.D.O.)
| | - Heinz D. Osiewacz
- Institute of Molecular Biosciences, Faculty of Biosciences, Goethe-University Frankfurt, 60438 Frankfurt am Main, Germany; (D.H.); (A.H.); (H.D.O.)
| | - David Meierhofer
- Max Planck Institute for Molecular Genetics, Ihnestraße 63-73, 14195 Berlin, Germany;
| | - Georg Auburger
- Goethe University Frankfurt, University Hospital, Clinic of Neurology, Experimental Neurology, Heinrich Hoffmann Str. 7, 60590 Frankfurt am Main, Germany; (J.K.); (S.G.); (A.R.K.)
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Min Y, Yu D, Yang J, Zhao W, Zhang L, Bai Y, Guo C. Bioinformatics and expression analysis of proline metabolism-related gene families in alfalfa under saline-alkali stress. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2023; 205:108182. [PMID: 37977024 DOI: 10.1016/j.plaphy.2023.108182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Revised: 10/13/2023] [Accepted: 11/07/2023] [Indexed: 11/19/2023]
Abstract
Regulation of the proline metabolic pathway is essential for the accumulation of proline under abiotic stress and for the amelioration of plant stress resistance. Δ1-pyrroline-5-carboxylate synthase (P5CS), pyrroline-5-carboxylate reductase (P5CR), ornithine transaminase (δ-OAT), proline dehydrogenase (PDH), pyrroline-5-carboxylate dehydrogenase (P5CDH), and proline transporter (ProT) are the key enzymes in the proline metabolic pathway. However, the gene families responsible for proline metabolism have not yet been identified or reported in alfalfa. In this study, a total of 12 MsP5CSs, 4 MsP5CRs, 3 MsOATs, 6 MsPDHs, 2 MsP5CDHs, and 5 MsProTs were identified in the genome of alfalfa, and the members of the same subfamily had similar gene structures and conserved motifs. Analysis of cis-regulatory elements revealed the presence of light-responsive, hormone-regulated, and stress-responsive elements in the promoter regions of alfalfa proline metabolism-related genes. Following treatment with saline-alkali, the expression of MsP5CSs, MsP5CRs, MsOATs, and MsProTs was significantly upregulated, whereas the expression of MsPDH1.1, MsPDH1.3, and MsP5CDH was significantly downregulated. The proline content and enzyme activity of P5CS gradually increased, whereas the enzyme activity of PDH gradually decreased as the duration of stress increased. Root growth rates decreased upon MsP5CS1a suppression (MsP5CS1a-RNAi) in the hairy roots of alfalfa compared to the empty vector line under saline-alkali stress. These results show that proline metabolism-related genes play an important role in the saline-alkali stress tolerance of alfalfa and provide a theoretical basis for further research on the functions of proline metabolism-related genes in alfalfa in response to saline-alkali stress.
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Affiliation(s)
- Yuanfeng Min
- Key Laboratory of Molecular and Cytogenetics, College of Life Science and Technology, Harbin Normal University, Harbin, 150025, Heilongjiang Province, China
| | - Dian Yu
- Key Laboratory of Molecular and Cytogenetics, College of Life Science and Technology, Harbin Normal University, Harbin, 150025, Heilongjiang Province, China
| | - Jinghua Yang
- Key Laboratory of Molecular and Cytogenetics, College of Life Science and Technology, Harbin Normal University, Harbin, 150025, Heilongjiang Province, China
| | - Weidi Zhao
- Key Laboratory of Molecular and Cytogenetics, College of Life Science and Technology, Harbin Normal University, Harbin, 150025, Heilongjiang Province, China
| | - Lishuang Zhang
- Key Laboratory of Molecular and Cytogenetics, College of Life Science and Technology, Harbin Normal University, Harbin, 150025, Heilongjiang Province, China
| | - Yan Bai
- Key Laboratory of Molecular and Cytogenetics, College of Life Science and Technology, Harbin Normal University, Harbin, 150025, Heilongjiang Province, China.
| | - Changhong Guo
- Key Laboratory of Molecular and Cytogenetics, College of Life Science and Technology, Harbin Normal University, Harbin, 150025, Heilongjiang Province, China.
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Tarchevsky IA, Egorova AM. Participation of Proline in Plant Adaptation to Stress Factors and Its Application in Agrobiotechnology (Review). APPL BIOCHEM MICRO+ 2022. [DOI: 10.1134/s0003683822040160] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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6
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Anwar A, Wang K, Wang J, Shi L, Du L, Ye X. Expression of Arabidopsis Ornithine Aminotransferase (AtOAT) encoded gene enhances multiple abiotic stress tolerances in wheat. PLANT CELL REPORTS 2021; 40:1155-1170. [PMID: 33950277 DOI: 10.1007/s00299-021-02699-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 04/19/2021] [Indexed: 05/25/2023]
Abstract
The drought and salt tolerances of wheat were enhanced by ectopic expression of the Arabidopsis ornithine aminotransferase (AtOAT) encoded gene. The OAT was confirmed to play a role in proline biosynthesis in wheat. Proline (Pro) accumulation is a common response to both abiotic and biotic stresses in plants. Ornithine aminotransferase (OAT) is pyridoxal-5-phosphate dependent enzyme involved in plant proline biosynthesis. During stress condition, proline is synthesized via glutamate and ornithine pathways. The OAT is the key enzyme in ornithine pathway. In this study, an OAT gene AtOAT from Arabidopsis was expressed in wheat for its functional characterization under drought, salinity, and heat stress conditions. We found that the expression of AtOAT enhanced the drought and salt stress tolerances of wheat by increasing the proline content and peroxidase activity. In addition, it was confirmed that the expression of AtOAT also played a partial tolerance to heat stress in the transgenic wheat plants. Moreover, quantitative real-time PCR (qRT-PCR) analysis showed that the transformation of AtOAT up-regulated the expression of the proline biosynthesis associated genes TaOAT, TaP5CS, and TaP5CR, and down-regulated that of the proline catabolism related gene TaP5CDH in the transgenic plants under stress conditions. Moreover, the genes involved in ornithine pathway (Orn-OAT-P5C/GSA-P5CR-Pro) were up-regulated along with the up-regulation of those genes involved in glutamate pathway (Glu-P5CS-P5C/GSA-P5CR-Pro). Therefore, we concluded that the expression of AtOAT enhanced wheat abiotic tolerance via modifying the proline biosynthesis by up-regulating the expression of the proline biosynthesis-associated genes and down-regulating that of the proline catabolic gene under stresses condition.
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Affiliation(s)
- Alia Anwar
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China
| | - Ke Wang
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China
| | - Jing Wang
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China
| | - Lei Shi
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China
| | - Lipu Du
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China
| | - Xingguo Ye
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China.
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7
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Ozturk M, Turkyilmaz Unal B, García-Caparrós P, Khursheed A, Gul A, Hasanuzzaman M. Osmoregulation and its actions during the drought stress in plants. PHYSIOLOGIA PLANTARUM 2021; 172:1321-1335. [PMID: 33280137 DOI: 10.1111/ppl.13297] [Citation(s) in RCA: 137] [Impact Index Per Article: 45.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 11/07/2020] [Accepted: 12/01/2020] [Indexed: 05/27/2023]
Abstract
Drought stress, which causes a decline in quality and quantity of crop yields, has become more accentuated these days due to climatic change. Serious measures need to be taken to increase the tolerance of crop plants to acute drought conditions likely to occur due to global warming. Drought stress causes many physiological and biochemical changes in plants, rendering the maintenance of osmotic adjustment highly crucial. The degree of plant resistance to drought varies with plant species and cultivars, phenological stages of the plant, and the duration of plant exposure to the stress. Osmoregulation in plants under low water potential relies on synthesis and accumulation of osmoprotectants or osmolytes such as soluble proteins, sugars, and sugar alcohols, quaternary ammonium compounds, and amino acids, like proline. This review highlights the role of osmolytes in water-stressed plants and of enzymes entailed in their metabolism. It will be useful, especially for researchers working on the development of drought-resistant crops by using the metabolic-engineering techniques.
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Affiliation(s)
- Munir Ozturk
- Botany Department, Centre for Environmental Studies, Ege University, Izmir, Turkey
| | - Bengu Turkyilmaz Unal
- Department of Biotechnology, Faculty of Science and Arts, Nigde Omer Halisdemir University, Nigde, Turkey
| | - Pedro García-Caparrós
- Agronomy Department of Superior School Engineering, University of Almería, Agrifood Campus of International Excellence, Almería, Spain
| | - Anum Khursheed
- Department of Biochemistry, Quaid-I-Azam University, Islamabad, Pakistan
| | - Alvina Gul
- Department of Plant Biotechnology, Atta-ur-Rahman School of Applied Biosciences, National University of Sciences and Technology, Islamabad, Pakistan
| | - Mirza Hasanuzzaman
- Department of Agronomy, Faculty of Agriculture, Sher-e-Bangla Agricultural University, Dhaka, Bangladesh
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Nadarajah KK. ROS Homeostasis in Abiotic Stress Tolerance in Plants. Int J Mol Sci 2020; 21:E5208. [PMID: 32717820 PMCID: PMC7432042 DOI: 10.3390/ijms21155208] [Citation(s) in RCA: 216] [Impact Index Per Article: 54.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 06/23/2020] [Accepted: 06/26/2020] [Indexed: 12/21/2022] Open
Abstract
Climate change-induced abiotic stress results in crop yield and production losses. These stresses result in changes at the physiological and molecular level that affect the development and growth of the plant. Reactive oxygen species (ROS) is formed at high levels due to abiotic stress within different organelles, leading to cellular damage. Plants have evolved mechanisms to control the production and scavenging of ROS through enzymatic and non-enzymatic antioxidative processes. However, ROS has a dual function in abiotic stresses where, at high levels, they are toxic to cells while the same molecule can function as a signal transducer that activates a local and systemic plant defense response against stress. The effects, perception, signaling, and activation of ROS and their antioxidative responses are elaborated in this review. This review aims to provide a purview of processes involved in ROS homeostasis in plants and to identify genes that are triggered in response to abiotic-induced oxidative stress. This review articulates the importance of these genes and pathways in understanding the mechanism of resistance in plants and the importance of this information in breeding and genetically developing crops for resistance against abiotic stress in plants.
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Affiliation(s)
- Kalaivani K Nadarajah
- Department of Biological Sciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM BANGI, Malaysia
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9
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Differential regulation of genes co-involved in aroma production and stress amelioration during salt acclimation in indica rice cultivars. Biologia (Bratisl) 2020. [DOI: 10.2478/s11756-020-00418-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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10
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D'Amours O, Calvo É, Bourassa S, Vincent P, Blondin P, Sullivan R. Proteomic markers of low and high fertility bovine spermatozoa separated by Percoll gradient. Mol Reprod Dev 2019; 86:999-1012. [DOI: 10.1002/mrd.23174] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 04/04/2019] [Accepted: 05/05/2019] [Indexed: 01/07/2023]
Affiliation(s)
- Olivier D'Amours
- Département d'obstétrique, Gynécologie et ReproductionCentre de Recherche du Centre Hospitalier de l'Université Laval Québec Québec Canada
| | - Ézéquiel Calvo
- Proteomic Core FacilityCentre de Recherche du Centre Hospitalier de l'Université Laval, Axe Reproduction, Santé de la mère et de l'enfant Québec Québec Canada
| | - Sylvie Bourassa
- Proteomic Core FacilityCentre de Recherche du Centre Hospitalier de l'Université Laval, Axe Reproduction, Santé de la mère et de l'enfant Québec Québec Canada
| | - Patrick Vincent
- Department of Research and DevelopmentSemex Alliance, L'Alliance Boviteq Inc Saint‐Hyacinthe Québec Canada
| | - Patrick Blondin
- Department of Research and DevelopmentSemex Alliance, L'Alliance Boviteq Inc Saint‐Hyacinthe Québec Canada
| | - Robert Sullivan
- Département d'obstétrique, Gynécologie et ReproductionCentre de Recherche du Centre Hospitalier de l'Université Laval Québec Québec Canada
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Blume C, Ost J, Mühlenbruch M, Peterhänsel C, Laxa M. Low CO2 induces urea cycle intermediate accumulation in Arabidopsis thaliana. PLoS One 2019; 14:e0210342. [PMID: 30650113 PMCID: PMC6334940 DOI: 10.1371/journal.pone.0210342] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 12/20/2018] [Indexed: 12/26/2022] Open
Abstract
The non-proteinogenic amino acid ornithine links several stress response pathways. From a previous study we know that ornithine accumulates in response to low CO2. To investigate ornithine accumulation in plants, we shifted plants to either low CO2 or low light. Both conditions increased carbon limitation, but only low CO2 also increased the rate of photorespiration. Changes in metabolite profiles of light- and CO2-limited plants were quite similar. Several amino acids that are known markers of senescence accumulated strongly under both conditions. However, urea cycle intermediates respond differently between the two treatments. While the levels of both ornithine and citrulline were much higher in plants shifted to 100 ppm CO2 compared to those kept in 400 ppm CO2, their metabolite abundance did not significantly change in response to a light limitation. Furthermore, both ornithine and citrulline accumulation is independent from sugar starvation. Exogenous supplied sugar did not significantly change the accumulation of the two metabolites in low CO2-stressed plants, while the accumulation of other amino acids was reduced by about 50%. Gene expression measurements showed a reduction of the entire arginine biosynthetic pathway in response to low CO2. Genes in both proline biosynthesis and degradation were induced. Hence, proline did not accumulate in response to low CO2 like observed for many other stresses. We propose that excess of nitrogen re-fixed during photorespiration can be alternatively stored in ornithine and citrulline under low CO2 conditions. Furthermore, ornithine is converted to pyrroline-5-carboxylate by the action of δOAT.
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Affiliation(s)
- Christian Blume
- Institute of Botany, Leibniz University Hannover, Hannover, Germany
| | - Julia Ost
- Institute of Botany, Leibniz University Hannover, Hannover, Germany
| | | | | | - Miriam Laxa
- Institute of Botany, Leibniz University Hannover, Hannover, Germany
- * E-mail:
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12
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Anwar A, She M, Wang K, Riaz B, Ye X. Biological Roles of Ornithine Aminotransferase (OAT) in Plant Stress Tolerance: Present Progress and Future Perspectives. Int J Mol Sci 2018; 19:ijms19113681. [PMID: 30469329 PMCID: PMC6274847 DOI: 10.3390/ijms19113681] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 11/14/2018] [Accepted: 11/16/2018] [Indexed: 02/06/2023] Open
Abstract
Plant tolerance to biotic and abiotic stresses is complicated by interactions between different stresses. Maintaining crop yield under abiotic stresses is the most daunting challenge for breeding resilient crop varieties. In response to environmental stresses, plants produce several metabolites, such as proline (Pro), polyamines (PAs), asparagine, serine, carbohydrates including glucose and fructose, and pools of antioxidant reactive oxygen species. Among these metabolites, Pro has long been known to accumulate in cells and to be closely related to drought, salt, and pathogen resistance. Pyrroline-5-carboxylate (P5C) is a common intermediate of Pro synthesis and metabolism that is produced by ornithine aminotransferase (OAT), an enzyme that functions in an alternative Pro metabolic pathway in the mitochondria under stress conditions. OAT is highly conserved and, to date, has been found in all prokaryotic and eukaryotic organisms. In addition, ornithine (Orn) and arginine (Arg) are both precursors of PAs, which confer plant resistance to drought and salt stresses. OAT is localized in the cytosol in prokaryotes and fungi, while OAT is localized in the mitochondria in higher plants. We have comprehensively reviewed the research on Orn, Arg, and Pro metabolism in plants, as all these compounds allow plants to tolerate different kinds of stresses.
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Affiliation(s)
- Alia Anwar
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Maoyun She
- School of Veterinary and Life Sciences, Murdoch University, WA 6150, Australia.
| | - Ke Wang
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Bisma Riaz
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Xingguo Ye
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
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13
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Hoermiller II, Naegele T, Augustin H, Stutz S, Weckwerth W, Heyer AG. Subcellular reprogramming of metabolism during cold acclimation in Arabidopsis thaliana. PLANT, CELL & ENVIRONMENT 2017; 40:602-610. [PMID: 27642699 DOI: 10.1111/pce.12836] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 09/10/2016] [Indexed: 05/18/2023]
Abstract
Metabolite changes in plant leaves during exposure to low temperatures involve re-allocation of a large number of metabolites between sub-cellular compartments. Therefore, metabolite determination at the whole cell level may be insufficient for interpretation of the functional significance of cellular compounds. To investigate the cold-induced metabolite dynamics at the level of individual sub-cellular compartments, an integrative platform was developed that combines quantitative metabolite profiling by gas chromatography coupled to mass spectrometry (GC-MS) with the non-aqueous fractionation technique allowing separation of cytosol, vacuole and the plastidial compartment. Two mutants of Arabidopsis thaliana representing antipodes in the diversion of carbohydrate metabolism between sucrose and starch were compared to Col-0 wildtype before and after cold acclimation to investigate interactions of cold acclimation with subcellular re-programming of metabolism. A multivariate analysis of the data set revealed dominant effects of compartmentation on metabolite concentrations that were modulated by environmental condition and genetic determinants. While for both, the starchless mutant of plastidial phospho-gluco mutase (pgm) and a mutant defective in sucrose-phosphate synthase A1, metabolic constraints, especially at low temperature, could be uncovered based on subcellularly resolved metabolite profiles, only pgm had lowered freezing tolerance. Metabolic profiles of pgm point to redox imbalance as a possible reason for reduced cold acclimation capacity.
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Affiliation(s)
- Imke I Hoermiller
- Institute of Biomaterials and Biomolecular Systems, Department of Plant Biotechnology, University of Stuttgart, 70569, Stuttgart, Germany
| | - Thomas Naegele
- Department of Ecogenomics and Systems Biology, University of Vienna, Althanstr. 14, 1090, Vienna, Austria
- Vienna Metabolomics Center (VIME), University of Vienna, Althanstr. 14, 1090, Vienna, Austria
| | - Hanna Augustin
- Institute of Biomaterials and Biomolecular Systems, Department of Plant Biotechnology, University of Stuttgart, 70569, Stuttgart, Germany
| | - Simon Stutz
- Institute of Biomaterials and Biomolecular Systems, Department of Plant Biotechnology, University of Stuttgart, 70569, Stuttgart, Germany
| | - Wolfram Weckwerth
- Department of Ecogenomics and Systems Biology, University of Vienna, Althanstr. 14, 1090, Vienna, Austria
- Vienna Metabolomics Center (VIME), University of Vienna, Althanstr. 14, 1090, Vienna, Austria
| | - Arnd G Heyer
- Institute of Biomaterials and Biomolecular Systems, Department of Plant Biotechnology, University of Stuttgart, 70569, Stuttgart, Germany
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Ginguay A, Cynober L, Curis E, Nicolis I. Ornithine Aminotransferase, an Important Glutamate-Metabolizing Enzyme at the Crossroads of Multiple Metabolic Pathways. BIOLOGY 2017; 6:biology6010018. [PMID: 28272331 PMCID: PMC5372011 DOI: 10.3390/biology6010018] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 02/23/2017] [Accepted: 02/24/2017] [Indexed: 02/06/2023]
Abstract
Ornithine δ-aminotransferase (OAT, E.C. 2.6.1.13) catalyzes the transfer of the δ-amino group from ornithine (Orn) to α-ketoglutarate (aKG), yielding glutamate-5-semialdehyde and glutamate (Glu), and vice versa. In mammals, OAT is a mitochondrial enzyme, mainly located in the liver, intestine, brain, and kidney. In general, OAT serves to form glutamate from ornithine, with the notable exception of the intestine, where citrulline (Cit) or arginine (Arg) are end products. Its main function is to control the production of signaling molecules and mediators, such as Glu itself, Cit, GABA, and aliphatic polyamines. It is also involved in proline (Pro) synthesis. Deficiency in OAT causes gyrate atrophy, a rare but serious inherited disease, a further measure of the importance of this enzyme.
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Affiliation(s)
- Antonin Ginguay
- Clinical Chemistry, Cochin Hospital, GH HUPC, AP-HP, 75014 Paris, France.
- Laboratory of Biological Nutrition, EA 4466 PRETRAM, Faculté de Pharmacie, Université Paris Descartes, 75006 Paris, France.
| | - Luc Cynober
- Clinical Chemistry, Cochin Hospital, GH HUPC, AP-HP, 75014 Paris, France.
- Laboratory of Biological Nutrition, EA 4466 PRETRAM, Faculté de Pharmacie, Université Paris Descartes, 75006 Paris, France.
| | - Emmanuel Curis
- Laboratoire de biomathématiques, plateau iB², Faculté de Pharmacie, Université Paris Descartes, 75006 Paris, France.
- UMR 1144, INSERM, Université Paris Descartes, 75006 Paris, France.
- UMR 1144, Université Paris Descartes, 75006 Paris, France.
- Service de biostatistiques et d'informatique médicales, hôpital Saint-Louis, Assistance publique-hôpitaux de Paris, 75010 Paris, France.
| | - Ioannis Nicolis
- Laboratoire de biomathématiques, plateau iB², Faculté de Pharmacie, Université Paris Descartes, 75006 Paris, France.
- EA 4064 "Épidémiologie environnementale: Impact sanitaire des pollutions", Faculté de Pharmacie, Université Paris Descartes, 75006 Paris, France.
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15
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Yang Y, Yang S, Li J, Deng Y, Zhang Z, Xu S, Guo W, Zhong C, Zhou R, Shi S. Transcriptome analysis of the Holly mangrove Acanthus ilicifolius and its terrestrial relative, Acanthus leucostachyus, provides insights into adaptation to intertidal zones. BMC Genomics 2015; 16:605. [PMID: 26272068 PMCID: PMC4536770 DOI: 10.1186/s12864-015-1813-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2015] [Accepted: 08/03/2015] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND Acanthus is a unique genus consisting of both true mangrove and terrestrial species; thus, it represents an ideal system for studying the origin and adaptive evolution of mangrove plants to intertidal environments. However, little is known regarding the two respects of mangrove species in Acanthus. In this study, we sequenced the transcriptomes of the pooled roots and leaves tissues for a mangrove species, Acanthus ilicifolius, and its terrestrial congener, A. leucostachyus, to illustrate the origin of the mangrove species in this genus and their adaptive evolution to harsh habitats. RESULTS We obtained 73,039 and 69,580 contigs with N50 values of 741 and 1557 bp for A. ilicifolius and A. leucostachyus, respectively. Phylogenetic analyses based on four nuclear segments and three chloroplast fragments revealed that mangroves and terrestrial species in Acanthus fell into different clades, indicating a single origin of the mangrove species in Acanthus. Based on 6634 orthologs, A. ilicifolius and A. leucostachyus were found to be highly divergent, with a peak of synonymous substitution rate (Ks) distribution of 0.145 and an estimated divergence time of approximately 16.8 million years ago (MYA). The transgression in the Early to Middle Miocene may be the major reason for the entry of the mangrove lineage of Acanthus into intertidal environments. Gene ontology (GO) classifications of the full transcriptomes did not show any apparent differences between A. ilicifolius and A. leucostachyus, suggesting the absence of gene components specific to the mangrove transcriptomes. A total of 99 genes in A. ilicifolius were identified with signals of positive selection. Twenty-three of the 99 positively selected genes (PSGs) were found to be involved in salt, heat and ultraviolet stress tolerance, seed germination and embryo development under periodic inundation. These stress-tolerance related PSGs may be crucial for the adaptation of the mangrove species in this genus to stressful marine environments and may contribute to speciation in Acanthus. CONCLUSIONS We characterized the transcriptomes of one mangrove species of Acanthus, A. ilicifolius, and its terrestrial relative, A. leucostachyus, and provided insights into the origin of the mangrove Acanthus species and their adaptive evolution to abiotic stresses in intertidal environments.
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Affiliation(s)
- Yuchen Yang
- State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources, Sun Yat-sen University, Guangzhou, 510275, China.
| | - Shuhuan Yang
- State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources, Sun Yat-sen University, Guangzhou, 510275, China.
| | - Jianfang Li
- State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources, Sun Yat-sen University, Guangzhou, 510275, China.
| | - Yunfei Deng
- Key Laboratory of Plant Resource Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Science, Guangzhou, 510650, China.
| | - Zhang Zhang
- State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources, Sun Yat-sen University, Guangzhou, 510275, China.
| | - Shaohua Xu
- State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources, Sun Yat-sen University, Guangzhou, 510275, China.
| | - Wuxia Guo
- State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources, Sun Yat-sen University, Guangzhou, 510275, China.
| | - Cairong Zhong
- Hainan Dongzhai Harbor National Nature Reserve, Haikou, 571129, China.
| | - Renchao Zhou
- State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources, Sun Yat-sen University, Guangzhou, 510275, China.
| | - Suhua Shi
- State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources, Sun Yat-sen University, Guangzhou, 510275, China.
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Kang S, Zhang Z, Richardson J, Shah B, Gupta S, Huang CJ, Qiu J, Le N, Lin H, Bondarenko PV. Metabolic markers associated with high mannose glycan levels of therapeutic recombinant monoclonal antibodies. J Biotechnol 2015; 203:22-31. [DOI: 10.1016/j.jbiotec.2015.03.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Revised: 02/28/2015] [Accepted: 03/05/2015] [Indexed: 01/21/2023]
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17
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Kanani A, Zaini F, Kordbacheh P, Falahati M, Rezaie S, Daie R, Farahyar S, Safara M, Fateh R, Faghihloo E, Fattahi A, Heidari M. Identification of Azole Resistance Markers in Clinical Isolates of Candida tropicalis Using cDNA-AFLP Method. J Clin Lab Anal 2015; 30:266-72. [PMID: 25873256 DOI: 10.1002/jcla.21847] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Accepted: 02/23/2015] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND Global reports have highlighted the increasing prevalence of Candida tropicalis infections as well as organism(') s drug resistance. This study aimed at identifying azole resistance markers in clinical isolates of C. tropicalis, which will be a great resource for developing new drugs. METHODS Two susceptible and resistant isolates of C. tropicalis were recovered from an epidemiological investigation of candidiasis in immunocompromised patients. C. tropicalis ATCC 750 was used as reference strain. Antifungal susceptibility to fluconazole and itraconazole was determined using Clinical and Laboratory Standards Institute (CLSI) method. Complementary DNA-amplified fragment length polymorphism (cDNA-AFLP) technology and real-time reverse-transcriptase (RT) PCR were used for identification of potential genes involved in azole resistance of C. tropicalis clinical isolates. RESULTS Five genes encoding the following enzymes were identified as superoxide dismutase (SOD) implicated in antioxidant defense, ornithine aminotransferase (OAT), acetyl ornithine aminotransferase (ACOAT), adenosylmethionine-8-amino-7-oxononanoate aminotransferase (DAPA AT), and 4-aminobutyrate aminotransferase (ABAT)-belonging to pyridoxal phosphate (PLP) dependent enzymes and acting in an important physiological role in many fungal-cell cycles. Real-time RT-PCR confirmed mRNA level of the aforementioned genes. CONCLUSION Our findings showed that factors such as PLP-dependent enzymes and SOD might be implicated in drug resistance in C. tropicalis clinical isolate. Therefore, further studies are required to explore the accurate biological functions of the mentioned genes that would be helpful for effective drug development.
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Affiliation(s)
- Ali Kanani
- Department of Medical Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Farideh Zaini
- Department of Medical Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Parivash Kordbacheh
- Department of Medical Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Mehraban Falahati
- Department of Medical Mycology and Parasitology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Sassan Rezaie
- Department of Medical Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Roshanak Daie
- Department of Medical Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Shirin Farahyar
- Department of Medical Mycology and Parasitology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Mahin Safara
- Department of Medical Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Roohollah Fateh
- Department of Microbiology and Immunology, Faculty of Medicine, Qom University of Medical Sciences, Qom, Iran
| | - Ebrahim Faghihloo
- Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Azam Fattahi
- Department of Medical Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Mansour Heidari
- Department of Medical Genetics, Tehran University of Medical Sciences, Tehran, Iran
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18
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Qamar A, Mysore KS, Senthil-Kumar M. Role of proline and pyrroline-5-carboxylate metabolism in plant defense against invading pathogens. FRONTIERS IN PLANT SCIENCE 2015; 6:503. [PMID: 26217357 PMCID: PMC4491715 DOI: 10.3389/fpls.2015.00503] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 06/22/2015] [Indexed: 05/18/2023]
Abstract
Pyrroline-5-carboxylate (P5C) is an intermediate product of both proline biosynthesis and catabolism. Recent evidences indicate that proline-P5C metabolism is tightly regulated in plants, especially during pathogen infection and abiotic stress. However, role of P5C and its metabolism in plants has not yet been fully understood. Studies indicate that P5C synthesized in mitochondria has a role in both resistance (R)-gene-mediated and non-host resistance against invading pathogens. Proline dehydrogenase and delta-ornithine amino transferase-encoding genes, both involved in P5C synthesis in mitochondria are implicated in defense response of Nicotiana benthamiana and Arabidopsis thaliana against bacterial pathogens. Such defense response is proposed to involve salicylic acid-dependent pathway, reactive oxygen species (ROS) and hypersensitive response (HR)-associated cell death. Recently HR, a form of programmed cell death (PCD), has been proposed to be induced by changes in mitochondrial P5C synthesis or the increase in P5C levels per se in plants inoculated with either a host pathogen carrying suitable avirulent (Avr) gene or a non-host pathogen. Consistently, A. thaliana mutant plants deficient in P5C catabolism showed HR like cell death when grown in external P5C or proline supplemented medium. Similarly, yeast and plant cells under oxidative stress were shown to increase ROS production and PCD due to increase in P5C levels. Similar mechanism has also been reported as one of the triggers for apoptosis in mammalian cells. This review critically analyzes results from various studies and enumerates the pathways for regulation of P5C levels in the plant cell, especially in mitochondria, during pathogen infection. Further, mechanisms regulating P5C- mediated defense responses, namely HR are outlined. This review also provides new insights into the differential role of proline-P5C metabolism in plants exposed to pathogen infection.
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Affiliation(s)
- Aarzoo Qamar
- National Institute of Plant Genome ResearchNew Delhi, India
| | | | - Muthappa Senthil-Kumar
- National Institute of Plant Genome ResearchNew Delhi, India
- *Correspondence: Muthappa Senthil-Kumar, National Institute of Plant Genome Research, Aruna Asaf Ali Marg, P. O. Box 10531, New Delhi 110067, India,
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19
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Winter G, Todd CD, Trovato M, Forlani G, Funck D. Physiological implications of arginine metabolism in plants. FRONTIERS IN PLANT SCIENCE 2015; 6:534. [PMID: 26284079 PMCID: PMC4520006 DOI: 10.3389/fpls.2015.00534] [Citation(s) in RCA: 273] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 06/29/2015] [Indexed: 05/18/2023]
Abstract
Nitrogen is a limiting resource for plant growth in most terrestrial habitats since large amounts of nitrogen are needed to synthesize nucleic acids and proteins. Among the 21 proteinogenic amino acids, arginine has the highest nitrogen to carbon ratio, which makes it especially suitable as a storage form of organic nitrogen. Synthesis in chloroplasts via ornithine is apparently the only operational pathway to provide arginine in plants, and the rate of arginine synthesis is tightly regulated by various feedback mechanisms in accordance with the overall nutritional status. While several steps of arginine biosynthesis still remain poorly characterized in plants, much wider attention has been paid to inter- and intracellular arginine transport as well as arginine-derived metabolites. A role of arginine as alternative source besides glutamate for proline biosynthesis is still discussed controversially and may be prevented by differential subcellular localization of enzymes. Apparently, arginine is a precursor for nitric oxide (NO), although the molecular mechanism of NO production from arginine remains unclear in higher plants. In contrast, conversion of arginine to polyamines is well documented, and in several plant species also ornithine can serve as a precursor for polyamines. Both NO and polyamines play crucial roles in regulating developmental processes as well as responses to biotic and abiotic stress. It is thus conceivable that arginine catabolism serves on the one hand to mobilize nitrogen storages, while on the other hand it may be used to fine-tune development and defense mechanisms against stress. This review summarizes the recent advances in our knowledge about arginine metabolism, with a special focus on the model plant Arabidopsis thaliana, and pinpoints still unresolved critical questions.
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Affiliation(s)
- Gudrun Winter
- Laboratory of Plant Physiology and Biochemistry, Department of Biology, University of Konstanz, Konstanz, Germany
| | | | - Maurizio Trovato
- Department of Biology and Biotechnology, Sapienza University of Rome, Rome, Italy
| | - Giuseppe Forlani
- Laboratory of Plant Physiology and Biochemistry, Department of Life Science and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Dietmar Funck
- Laboratory of Plant Physiology and Biochemistry, Department of Biology, University of Konstanz, Konstanz, Germany
- *Correspondence: Dietmar Funck, Laboratory of Plant Physiology and Biochemistry, Department of Biology, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany,
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Fichman Y, Gerdes SY, Kovács H, Szabados L, Zilberstein A, Csonka LN. Evolution of proline biosynthesis: enzymology, bioinformatics, genetics, and transcriptional regulation. Biol Rev Camb Philos Soc 2014; 90:1065-99. [PMID: 25367752 DOI: 10.1111/brv.12146] [Citation(s) in RCA: 106] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Revised: 08/27/2014] [Accepted: 09/02/2014] [Indexed: 12/17/2022]
Abstract
Proline is not only an essential component of proteins but it also has important roles in adaptation to osmotic and dehydration stresses, redox control, and apoptosis. Here, we review pathways of proline biosynthesis in the three domains of life. Pathway reconstruction from genome data for hundreds of eubacterial and dozens of archaeal and eukaryotic organisms revealed evolutionary conservation and variations of this pathway across different taxa. In the most prevalent pathway of proline synthesis, glutamate is phosphorylated to γ-glutamyl phosphate by γ-glutamyl kinase, reduced to γ-glutamyl semialdehyde by γ-glutamyl phosphate reductase, cyclized spontaneously to Δ(1)-pyrroline-5-carboxylate and reduced to proline by Δ(1)-pyrroline-5-carboxylate reductase. In higher plants and animals the first two steps are catalysed by a bi-functional Δ(1) -pyrroline-5-carboxylate synthase. Alternative pathways of proline formation use the initial steps of the arginine biosynthetic pathway to ornithine, which can be converted to Δ(1)-pyrroline-5-carboxylate by ornithine aminotransferase and then reduced to proline or converted directly to proline by ornithine cyclodeaminase. In some organisms, the latter pathways contribute to or could be fully responsible for the synthesis of proline. The conservation of proline biosynthetic enzymes and significance of specific residues for catalytic activity and allosteric regulation are analysed on the basis of protein structural data, multiple sequence alignments, and mutant studies, providing novel insights into proline biosynthesis in organisms. We also discuss the transcriptional control of the proline biosynthetic genes in bacteria and plants.
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Affiliation(s)
- Yosef Fichman
- Department of Molecular Biology and Ecology of Plants, Tel-Aviv University, Tel-Aviv 6997803, Israel
| | - Svetlana Y Gerdes
- Mathematics and Computer Science Division, Argonne National Laboratory, Argonne, IL, 60439, U.S.A
| | - Hajnalka Kovács
- Institute of Plant Biology, Biological Research Centre, 6726 Szeged, Hungary
| | - László Szabados
- Institute of Plant Biology, Biological Research Centre, 6726 Szeged, Hungary
| | - Aviah Zilberstein
- Department of Molecular Biology and Ecology of Plants, Tel-Aviv University, Tel-Aviv 6997803, Israel
| | - Laszlo N Csonka
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, U.S.A
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Quitterer F, Beck P, Bacher A, Groll M. Pyrrolysin-Synthase (PylD) katalysiert die Bildung von Pyrrolin- und Tetrahydropyridinringen in Aminosäuren. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201402595] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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22
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Quitterer F, Beck P, Bacher A, Groll M. The formation of pyrroline and tetrahydropyridine rings in amino acids catalyzed by pyrrolysine synthase (PylD). Angew Chem Int Ed Engl 2014; 53:8150-3. [PMID: 24916332 DOI: 10.1002/anie.201402595] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Indexed: 11/11/2022]
Abstract
The dehydrogenase PylD catalyzes the ultimate step of the pyrrolysine pathway by converting the isopeptide L-lysine-Nε-3R-methyl-D-ornithine to the 22nd proteinogenic amino acid. In this study, we demonstrate how PylD can be harnessed to oxidize various isopeptides to novel amino acids by combining chemical synthesis with enzyme kinetics and X-ray crystallography. The data enable a detailed description of the PylD reaction trajectory for the biosynthesis of pyrroline and tetrahydropyridine rings as constituents of pyrrolysine analogues.
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Affiliation(s)
- Felix Quitterer
- Center for Integrated Protein Science Munich (CIPSM), Lehrstuhl für Biochemie, Technische Universität München, Lichtenbergstrasse 4, 85748 Garching (Germany)
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Zeier J. New insights into the regulation of plant immunity by amino acid metabolic pathways. PLANT, CELL & ENVIRONMENT 2013; 36:2085-103. [PMID: 23611692 DOI: 10.1111/pce.12122] [Citation(s) in RCA: 212] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Revised: 04/09/2013] [Accepted: 04/14/2013] [Indexed: 05/20/2023]
Abstract
Besides defence pathways regulated by classical stress hormones, distinct amino acid metabolic pathways constitute integral parts of the plant immune system. Mutations in several genes involved in Asp-derived amino acid biosynthetic pathways can have profound impact on plant resistance to specific pathogen types. For instance, amino acid imbalances associated with homoserine or threonine accumulation elevate plant immunity to oomycete pathogens but not to pathogenic fungi or bacteria. The catabolism of Lys produces the immune signal pipecolic acid (Pip), a cyclic, non-protein amino acid. Pip amplifies plant defence responses and acts as a critical regulator of plant systemic acquired resistance, defence priming and local resistance to bacterial pathogens. Asp-derived pyridine nucleotides influence both pre- and post-invasion immunity, and the catabolism of branched chain amino acids appears to affect plant resistance to distinct pathogen classes by modulating crosstalk of salicylic acid- and jasmonic acid-regulated defence pathways. It also emerges that, besides polyamine oxidation and NADPH oxidase, Pro metabolism is involved in the oxidative burst and the hypersensitive response associated with avirulent pathogen recognition. Moreover, the acylation of amino acids can control plant resistance to pathogens and pests by the formation of protective plant metabolites or by the modulation of plant hormone activity.
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Affiliation(s)
- Jürgen Zeier
- Department of Biology, Heinrich Heine University Düsseldorf, 40225, Düsseldorf, Germany
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Polacco JC, Mazzafera P, Tezotto T. Opinion: nickel and urease in plants: still many knowledge gaps. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2013; 199-200:79-90. [PMID: 23265321 DOI: 10.1016/j.plantsci.2012.10.010] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Revised: 10/19/2012] [Accepted: 10/20/2012] [Indexed: 05/22/2023]
Abstract
We propose experimental strategies to expand our understanding of the role of Ni in plants, beyond the Ni-metallocenter of urease, still the only identified Ni-containing plant enzyme. While Ni has been considered an essential mineral for plants there is a clear lack of knowledge of its involvement in metabolic steps except the urease-catalyzed conversion of urea to ammonia and bicarbonate. We argue that urease (and hence, Ni) plays an important role in optimal N-use efficiency under various N regimes by recycling urea-N, which is generated endogenously exclusively from arginase action on arginine. We further suggest that urease and arginase may connect different metabolic compartments under stress situations, and therefore may be involved in stress tolerance. To determine possible non-urease roles of Ni we call for experimental manipulation of both Ni and N availability in urease-negative mutants. Plant ureases have been shown to have defense roles, distinct from their ureolytic activity, and we call for investigation of whether Ni helps maintain a urease conformation or stability for these non-ureolytic defense roles. The beneficial effects of Ni at upper concentration limits have not been fully examined. We posit a "Ni strategy" of plants whose growth/performance is stimulated by unusual amounts of soil Ni, for defense and/or for maximal N-use efficiency. While we know little about Ni and urease roles in N metabolism and defense, virtually nothing is known about Ni roles in plant-microbial 'consortia.' And, much of what we know of Ni and urease is limited to only a few plants, e.g. soybean, potato and Arabidopsis, and we suggest studies vigorously extended to other plants.
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Affiliation(s)
- Joe C Polacco
- University of Missouri, Department of Biochemistry, Interdisciplinary Plant Group, Columbia, MO 65211, United States.
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You J, Hu H, Xiong L. An ornithine δ-aminotransferase gene OsOAT confers drought and oxidative stress tolerance in rice. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2012; 197:59-69. [PMID: 23116672 DOI: 10.1016/j.plantsci.2012.09.002] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Revised: 09/01/2012] [Accepted: 09/10/2012] [Indexed: 05/19/2023]
Abstract
Ornithine δ-aminotransferase (δ-OAT) is a pyridoxal-5'-phosphate-dependent enzyme that has been proposed to be involved in proline (Pro) and arginine (Arg) metabolism. However, the actual role of δ-OAT in abiotic responses in plants remains to be clarified. Here we characterized an ornithine δ-aminotransferase gene OsOAT that confers multi-stress tolerance in rice (Oryza sativa). We confirmed that OsOAT is a direct target of the stress-responsive NAC transcription factor SNAC2. OsOAT is responsive to multiple stresses and phytohormone treatments. Both ABA-dependent and ABA-independent pathways contributed to the drought-induced expression of OsOAT. Overexpression of the OsOAT gene in rice resulted in significantly enhanced drought and osmotic stress tolerance. Overexpression of OsOAT caused significantly increased δ-OAT activity and Pro accumulation under normal growth conditions. In addition, OsOAT-overexpressing plants showed significantly increased tolerance to oxidative stress. The glutathione (GSH) content and activity of reactive oxygen species (ROS)-scavenging enzymes, such as glutathione peroxidase, were also increased in OsOAT-overexpressing plants. We conclude that OsOAT is a target gene of SNAC2 and confers stress tolerance mainly through enhancing ROS-scavenging capacity and Pro pre-accumulation.
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Affiliation(s)
- Jun You
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China
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Ludin P, Woodcroft B, Ralph SA, Mäser P. In silico prediction of antimalarial drug target candidates. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2012; 2:191-9. [PMID: 24533280 DOI: 10.1016/j.ijpddr.2012.07.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2012] [Revised: 06/28/2012] [Accepted: 07/03/2012] [Indexed: 10/28/2022]
Abstract
The need for new antimalarials is persistent due to the emergence of drug resistant parasites. Here we aim to identify new drug targets in Plasmodium falciparum by phylogenomics among the Plasmodium spp. and comparative genomics to Homo sapiens. The proposed target discovery pipeline is largely independent of experimental data and based on the assumption that P. falciparum proteins are likely to be essential if (i) there are no similar proteins in the same proteome and (ii) they are highly conserved across the malaria parasites of mammals. This hypothesis was tested using sequenced Saccharomycetaceae species as a touchstone. Consecutive filters narrowed down the potential target space of P. falciparum to proteins that are likely to be essential, matchless in the human proteome, expressed in the blood stages of the parasite, and amenable to small molecule inhibition. The final set of 40 candidate drug targets was significantly enriched in essential proteins and comprised proven targets (e.g. dihydropteroate synthetase or enzymes of the non-mevalonate pathway), targets currently under investigation (e.g. calcium-dependent protein kinases), and new candidates of potential interest such as phosphomannose isomerase, phosphoenolpyruvate carboxylase, signaling components, and transporters. The targets were prioritized based on druggability indices and on the availability of in vitro assays. Potential inhibitors were inferred from similarity to known targets of other disease systems. The identified candidates from P. falciparum provide insight into biochemical peculiarities and vulnerable points of the malaria parasite and might serve as starting points for rational drug discovery.
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Affiliation(s)
- Philipp Ludin
- Swiss Tropical and Public Health Institute, 4002 Basel, Switzerland ; University of Basel, 4000 Basel, Switzerland
| | - Ben Woodcroft
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria 3010, Australia
| | - Stuart A Ralph
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria 3010, Australia
| | - Pascal Mäser
- Swiss Tropical and Public Health Institute, 4002 Basel, Switzerland ; University of Basel, 4000 Basel, Switzerland
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Senthil-Kumar M, Mysore KS. Ornithine-delta-aminotransferase and proline dehydrogenase genes play a role in non-host disease resistance by regulating pyrroline-5-carboxylate metabolism-induced hypersensitive response. PLANT, CELL & ENVIRONMENT 2012; 35:1329-43. [PMID: 22321246 DOI: 10.1111/j.1365-3040.2012.02492.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Non-host disease resistance involves the production of hypersensitive response (HR), a programmed cell death (PCD) that occurs at the site of pathogen infection. Plant mitochondrial reactive oxygen species (ROS) production and red-ox changes play a major role in regulating such cell death. Proline catabolism reactions, especially pyrroline-5-carboxylate (P5C) accumulation, are known to produce ROS and contribute to cell death. Here we studied important genes related to proline synthesis and catabolism in the defence against host and non-host strains of Pseudomonas syringae in Nicotiana benthamiana and Arabidopsis. Our results show that ornithine delta-aminotransferase (δOAT) and proline dehydrogenases (ProDH1 and ProDH2) are involved in the defence against non-host pathogens. Silencing of these genes in N. benthamiana delayed occurrence of HR and favoured non-host pathogen growth. Arabidopsis mutants for these genes compromised non-host resistance and showed a decrease in non-host pathogen-induced ROS. Some of the genes involved in proline metabolism were also induced by a pathogen-carrying avirulence gene, indicating that proline metabolism is influenced during effector-triggered immunity (ETI). Our results demonstrate that δOAT and ProDH enzyme-mediated steps produce ROS in mitochondria and regulate non-host HR, thus contributing to non-host resistance in plants.
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Affiliation(s)
- Muthappa Senthil-Kumar
- Plant Biology Division, The Samuel Roberts Noble Foundation, 2510 Sam Noble Pkwy., Ardmore, Oklahoma 73402, USA
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da Rocha IMA, Vitorello VA, Silva JS, Ferreira-Silva SL, Viégas RA, Silva EN, Silveira JAG. Exogenous ornithine is an effective precursor and the δ-ornithine amino transferase pathway contributes to proline accumulation under high N recycling in salt-stressed cashew leaves. JOURNAL OF PLANT PHYSIOLOGY 2012; 169:41-9. [PMID: 21903295 DOI: 10.1016/j.jplph.2011.08.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2011] [Revised: 08/02/2011] [Accepted: 08/14/2011] [Indexed: 05/21/2023]
Abstract
The role of the δ-ornithine amino transferase (OAT) pathway in proline synthesis is still controversial and was assessed in leaves of cashew plants subjected to salinity. The activities of enzymes and the concentrations of metabolites involved in proline synthesis were examined in parallel with the capacity of exogenous ornithine and glutamate to induce proline accumulation. Proline accumulation was best correlated with OAT activity, which increased 4-fold and was paralleled by NADH oxidation coupled to the activities of OAT and Δ(1)-pyrroline-5-carboxylate reductase (P5CR), demonstrating the potential of proline synthesis via OAT/P5C. Overall, the activities of GS, GOGAT and aminating GDH remained practically unchanged under salinity. The activity of P5CR did not respond to NaCl whereas Δ(1)-pyrroline-5-carboxylate dehydrogenase was sharply repressed by salinity. We suggest that if the export of P5C from the mitochondria to the cytosol is possible, its subsequent conversion to proline by P5CR may be important. In a time-course experiment, proline accumulation was associated with disturbances in amino acid metabolism as indicated by large increases in the concentrations of ammonia, free amino acids, glutamine, arginine and ornithine. Conversely, glutamate concentrations increased moderately and only within the first 24h. Exogenous feeding of ornithine as a precursor was very effective in inducing proline accumulation in intact plants and leaf discs, in which proline concentrations were several times higher than glutamate-fed or salt-treated plants. Our data suggest that proline accumulation might be a consequence of salt-induced increase in N recycling, resulting in increased levels of ornithine and other metabolites involved with proline synthesis and OAT activity. Under these metabolic circumstances the OAT pathway might contribute significantly to proline accumulation in salt-stressed cashew leaves.
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Affiliation(s)
- Iza Marineves Almeida da Rocha
- Departamento de Bioquímica e Biologia Molecular/Instituto Nacional de Ciência e Tecnologia em Salinidade (INCTsal/CNPq), Universidade Federal do Ceará, CP 6033, CEP 60451-970, Fortaleza, Ceará, Brazil
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Gerasimova SV, Gorelova VV, Dorogina OV, Zhmud EV, Koval VS, Romanova AV, Kochetova AV, Shumny VK. Analysis of transcriptional activity of the Arabidopsis thaliana ornithine-delta-aminotransferase gene promoter. RUSS J GENET+ 2011. [DOI: 10.1134/s1022795411050073] [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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Zhang X, Shen L, Li F, Zhang Y, Meng D, Sheng J. Up-regulating arginase contributes to amelioration of chilling stress and the antioxidant system in cherry tomato fruits. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2010; 90:2195-202. [PMID: 20628998 DOI: 10.1002/jsfa.4070] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
BACKGROUND Arginase, which plays an important role in regulating the metabolism of L-arginine (Arg) in mammalian cells, has been reported to be involved in stress responses in higher plants. In view of the well-established roles of polyamines, nitric oxide and proline in plant tolerance to chilling stress, arginase may play an important role in fruit chilling tolerance by regulating the metabolism of Arg. However, the current information available on this is very limited. RESULTS Cherry tomatoes (Lycopersicon esculentum cv.Messina) at the mature green stage were treated with Arg or N(ω)--hydroxy-nor-L-arginine (nor-NOHA) and analysed for chilling injury, electrolyte leakage, malondialdehyde and proline contents and arginase and antioxidant enzyme (superoxide dismutase, catalase, peroxidaseand ascorbate peroxidase) activities during cold storage. The effects of low temperature on the transcriptional levels of two arginase genes (LeARG1 and LeARG2) were also evaluated. LeARG1 and LeARG2 expression and arginase activity were significantly induced by low temperature. Compared with the control, Arg treatment alleviated fruit chilling injury, reduced electrolyte leakage, malondialdehyde content and peroxidaseactivity and increased other parameters. Treatment with nor-NOHA caused the opposite effects. CONCLUSION Up-regulation of arginase activity and gene expression may be a chilling tolerance strategy in cherry tomato fruit. Inhibition of chilling-induced arginase activity could aggravate chilling injury and oxidation damage. Arginase appears to play an important role in the chilling resistance process of cherry tomato fruit induced by Arg.
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Affiliation(s)
- Xinhua Zhang
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
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Stránská J, Tylichová M, Kopecný D, Snégaroff J, Sebela M. Biochemical characterization of pea ornithine-delta-aminotransferase: substrate specificity and inhibition by di- and polyamines. Biochimie 2010; 92:940-8. [PMID: 20381578 DOI: 10.1016/j.biochi.2010.03.026] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2010] [Accepted: 03/30/2010] [Indexed: 11/20/2022]
Abstract
Ornithine-delta-aminotransferase (OAT, EC 2.6.1.13) catalyzes the transamination of L-ornithine to L-glutamate-gamma-semialdehyde. The physiological role of OAT in plants is not yet well understood. It is probably related to arginine catabolism resulting in glutamate but the enzyme has also been associated with stress-induced proline biosynthesis. We investigated the enzyme from pea (PsOAT) to assess whether diamines and polyamines may serve as substrates or they show inhibitory properties. First, a cDNA coding for PsOAT was cloned and expressed in Escherichia coli to obtain a recombinant protein with a C-terminal 6xHis tag. Recombinant PsOAT was purified under native conditions by immobilized metal affinity chromatography and its molecular and kinetic properties were characterized. Protein identity was confirmed by peptide mass fingerprinting after proteolytic digestion. The purified PsOAT existed as a monomer of 50 kDa and showed typical spectral properties of enzymes containing pyridoxal-5'-phosphate as a prosthetic group. The cofactor content of PsOAT was estimated to be 0.9 mol per mol of the monomer by a spectrophotometric analysis with phenylhydrazine. L-Ornithine was the best substrate (K(m)=15 mM) but PsOAT also slowly converted N(alpha)-acetyl-L-ornithine. In these reactions, 2-oxoglutarate was the exclusive amino group acceptor (K(m)=2mM). The enzyme had a basic optimal pH of 8.8 and displayed relatively high temperature optimum. Diamines and polyamines were not accepted as substrates. On the other hand, putrescine, spermidine and others represented weak non-competitive inhibitors. A model of the molecular structure of PsOAT was obtained using the crystal structure of human OAT as a template.
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Affiliation(s)
- Jana Stránská
- Department of Biochemistry, Faculty of Science, Palacký University, Olomouc, Czech Republic
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Lehmann S, Funck D, Szabados L, Rentsch D. Proline metabolism and transport in plant development. Amino Acids 2010; 39:949-62. [DOI: 10.1007/s00726-010-0525-3] [Citation(s) in RCA: 225] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Accepted: 02/10/2010] [Indexed: 01/21/2023]
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