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Magner ET, Freund Saxhaug K, Zambre A, Bruns K, Carroll P, Snell-Rood EC, Hegeman AD, Carter CJ. A multifunctional role for riboflavin in the yellow nectar of Capsicum baccatum and Capsicum pubescens. THE NEW PHYTOLOGIST 2024. [PMID: 38874372 DOI: 10.1111/nph.19886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2023] [Accepted: 05/14/2024] [Indexed: 06/15/2024]
Abstract
A few Capsicum (pepper) species produce yellow-colored floral nectar, but the chemical identity and biological function of the yellow pigment are unknown. A combination of analytical biochemistry techniques was used to identify the pigment that gives Capsicum baccatum and Capsicum pubescens nectars their yellow color. Microbial growth assays, visual modeling, and honey bee preference tests for artificial nectars containing riboflavin were used to assess potential biological roles for the nectar pigment. High concentrations of riboflavin (vitamin B2) give the nectars their intense yellow color. Nectars containing riboflavin generate reactive oxygen species when exposed to light and reduce microbial growth. Visual modeling also indicates that the yellow color is highly conspicuous to bees within the context of the flower. Lastly, field experiments demonstrate that honey bees prefer artificial nectars containing riboflavin. Some Capsicum nectars contain a yellow-colored vitamin that appears to play roles in (1) limiting microbial growth, (2) the visual attraction of bees, and (3) as a reward to nectar-feeding flower visitors (potential pollinators), which is especially interesting since riboflavin is an essential nutrient for brood rearing in insects. These results cumulatively suggest that the riboflavin found in some Capsicum nectars has several functions.
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Affiliation(s)
- Evin T Magner
- Department of Plant & Microbial Biology, University of Minnesota, 1479 Gortner Avenue, St. Paul, MN, 55108, USA
| | | | - Amod Zambre
- Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, MN, 55108, USA
| | - Kaitlyn Bruns
- Department of Plant & Microbial Biology, University of Minnesota, 1479 Gortner Avenue, St. Paul, MN, 55108, USA
| | - Patrick Carroll
- Department of Plant & Microbial Biology, University of Minnesota, 1479 Gortner Avenue, St. Paul, MN, 55108, USA
| | - Emilie C Snell-Rood
- Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, MN, 55108, USA
| | - Adrian D Hegeman
- Department of Plant & Microbial Biology, University of Minnesota, 1479 Gortner Avenue, St. Paul, MN, 55108, USA
- Department of Horticultural Science, University of Minnesota, St. Paul, MN, 55108, USA
| | - Clay J Carter
- Department of Plant & Microbial Biology, University of Minnesota, 1479 Gortner Avenue, St. Paul, MN, 55108, USA
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2
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Tamizhselvan P, Madhavan S, Constan-Aguilar C, Elrefaay ER, Liu J, Pěnčík A, Novák O, Cairó A, Hrtyan M, Geisler M, Tognetti VB. Chloroplast Auxin Efflux Mediated by ABCB28 and ABCB29 Fine-Tunes Salt and Drought Stress Responses in Arabidopsis. PLANTS (BASEL, SWITZERLAND) 2023; 13:7. [PMID: 38202315 PMCID: PMC10780339 DOI: 10.3390/plants13010007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Revised: 11/26/2023] [Accepted: 12/13/2023] [Indexed: 01/12/2024]
Abstract
Photosynthesis is among the first processes negatively affected by environmental cues and its performance directly determines plant cell fitness and ultimately crop yield. Primarily sites of photosynthesis, chloroplasts are unique sites also for the biosynthesis of precursors of the growth regulator auxin and for sensing environmental stress, but their role in intracellular auxin homeostasis, vital for plant growth and survival in changing environments, remains poorly understood. Here, we identified two ATP-binding cassette (ABC) subfamily B transporters, ABCB28 and ABCB29, which export auxin across the chloroplast envelope to the cytosol in a concerted action in vivo. Moreover, we provide evidence for an auxin biosynthesis pathway in Arabidopsis thaliana chloroplasts. The overexpression of ABCB28 and ABCB29 influenced stomatal regulation and resulted in significantly improved water use efficiency and survival rates during salt and drought stresses. Our results suggest that chloroplast auxin production and transport contribute to stomata regulation for conserving water upon salt stress. ABCB28 and ABCB29 integrate photosynthesis and auxin signals and as such hold great potential to improve the adaptation potential of crops to environmental cues.
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Affiliation(s)
- Prashanth Tamizhselvan
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology (CEITEC), Masaryk University, Kamenice 5, CZ-625 00 Brno, Czech Republic; (P.T.); (S.M.); (C.C.-A.); (E.R.E.); (A.C.); (M.H.)
| | - Sharmila Madhavan
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology (CEITEC), Masaryk University, Kamenice 5, CZ-625 00 Brno, Czech Republic; (P.T.); (S.M.); (C.C.-A.); (E.R.E.); (A.C.); (M.H.)
| | - Christian Constan-Aguilar
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology (CEITEC), Masaryk University, Kamenice 5, CZ-625 00 Brno, Czech Republic; (P.T.); (S.M.); (C.C.-A.); (E.R.E.); (A.C.); (M.H.)
| | - Eman Ryad Elrefaay
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology (CEITEC), Masaryk University, Kamenice 5, CZ-625 00 Brno, Czech Republic; (P.T.); (S.M.); (C.C.-A.); (E.R.E.); (A.C.); (M.H.)
| | - Jie Liu
- Department of Biology, University of Fribourg, CH-1700 Fribourg, Switzerland; (J.L.); (M.G.)
| | - Aleš Pěnčík
- Laboratory of Growth Regulators, Institute of Experimental Botany, The Czech Academy of Sciences, & Faculty of Science, Palacký University, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic; (A.P.); (O.N.)
| | - Ondřej Novák
- Laboratory of Growth Regulators, Institute of Experimental Botany, The Czech Academy of Sciences, & Faculty of Science, Palacký University, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic; (A.P.); (O.N.)
| | - Albert Cairó
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology (CEITEC), Masaryk University, Kamenice 5, CZ-625 00 Brno, Czech Republic; (P.T.); (S.M.); (C.C.-A.); (E.R.E.); (A.C.); (M.H.)
| | - Mónika Hrtyan
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology (CEITEC), Masaryk University, Kamenice 5, CZ-625 00 Brno, Czech Republic; (P.T.); (S.M.); (C.C.-A.); (E.R.E.); (A.C.); (M.H.)
| | - Markus Geisler
- Department of Biology, University of Fribourg, CH-1700 Fribourg, Switzerland; (J.L.); (M.G.)
| | - Vanesa Beatriz Tognetti
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology (CEITEC), Masaryk University, Kamenice 5, CZ-625 00 Brno, Czech Republic; (P.T.); (S.M.); (C.C.-A.); (E.R.E.); (A.C.); (M.H.)
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3
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Straube H, Straube J, Rinne J, Fischer L, Niehaus M, Witte CP, Herde M. An inosine triphosphate pyrophosphatase safeguards plant nucleic acids from aberrant purine nucleotides. THE NEW PHYTOLOGIST 2023; 237:1759-1775. [PMID: 36464781 DOI: 10.1111/nph.18656] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 11/22/2022] [Indexed: 06/17/2023]
Abstract
In plants, inosine is enzymatically introduced in some tRNAs, but not in other RNAs or DNA. Nonetheless, our data show that RNA and DNA from Arabidopsis thaliana contain (deoxy)inosine, probably derived from nonenzymatic adenosine deamination in nucleic acids and usage of (deoxy)inosine triphosphate (dITP and ITP) during nucleic acid synthesis. We combined biochemical approaches, LC-MS, as well as RNA-Seq to characterize a plant INOSINE TRIPHOSPHATE PYROPHOSPHATASE (ITPA) from A. thaliana, which is conserved in many organisms, and investigated the sources of deaminated purine nucleotides in plants. Inosine triphosphate pyrophosphatase dephosphorylates deaminated nucleoside di- and triphosphates to the respective monophosphates. ITPA loss-of-function causes inosine di- and triphosphate accumulation in vivo and an elevated inosine and deoxyinosine content in RNA and DNA, respectively, as well as salicylic acid (SA) accumulation, early senescence, and upregulation of transcripts associated with immunity and senescence. Cadmium-induced oxidative stress and biochemical inhibition of the INOSINE MONOPHOSPHATE DEHYDROGENASE leads to more IDP and ITP in the wild-type (WT), and this effect is enhanced in itpa mutants, suggesting that ITP originates from ATP deamination and IMP phosphorylation. Inosine triphosphate pyrophosphatase is part of a molecular protection system in plants, preventing the accumulation of (d)ITP and its usage for nucleic acid synthesis.
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Affiliation(s)
- Henryk Straube
- Department of Molecular Nutrition and Biochemistry of Plants, Leibniz Universität Hannover, Hannover, 30419, Germany
| | - Jannis Straube
- Department of Molecular Plant Breeding, Leibniz Universität Hannover, Hannover, 30419, Germany
| | - Jannis Rinne
- Department of Molecular Nutrition and Biochemistry of Plants, Leibniz Universität Hannover, Hannover, 30419, Germany
| | - Lisa Fischer
- Department of Molecular Nutrition and Biochemistry of Plants, Leibniz Universität Hannover, Hannover, 30419, Germany
| | - Markus Niehaus
- Department of Molecular Nutrition and Biochemistry of Plants, Leibniz Universität Hannover, Hannover, 30419, Germany
| | - Claus-Peter Witte
- Department of Molecular Nutrition and Biochemistry of Plants, Leibniz Universität Hannover, Hannover, 30419, Germany
| | - Marco Herde
- Department of Molecular Nutrition and Biochemistry of Plants, Leibniz Universität Hannover, Hannover, 30419, Germany
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4
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Zmuda AJ, Niehaus TD. Systems and strategies for plant protein expression. Methods Enzymol 2023; 680:3-34. [PMID: 36710015 DOI: 10.1016/bs.mie.2022.08.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
At least a quarter of the protein-encoding genes in plant genomes are predicted to encode enzymes for which no physiological function is known. Determining functions for these uncharacterized enzymes is key to understanding plant metabolism. Functional characterization typically requires expression and purification of recombinant enzymes to be used in enzyme assays and/or for protein structure elucidation studies. Here, we describe several practical considerations used to improve the heterologous expression and purification of Arabidopsis thaliana and Zea mays NAD(P)HX dehydratase (NAXD) and NAD(P)HX epimerase (NAXE), two enzymes that are involved in repair of chemically damaged NAD(P)H cofactors. We provide protocols for transit peptide prediction and construct design, expression in Escherichia coli, and purification of NAXD and NAXE. Many of these strategies are generally applicable to the purification of any plant protein.
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Affiliation(s)
- Anthony J Zmuda
- Department of Plant and Microbial Biology, University of Minnesota, St. Paul, MN, United States
| | - Thomas D Niehaus
- Department of Plant and Microbial Biology, University of Minnesota, St. Paul, MN, United States.
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5
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Luklová M, Novák J, Kopecká R, Kameniarová M, Gibasová V, Brzobohatý B, Černý M. Phytochromes and Their Role in Diurnal Variations of ROS Metabolism and Plant Proteome. Int J Mol Sci 2022; 23:ijms232214134. [PMID: 36430613 PMCID: PMC9695588 DOI: 10.3390/ijms232214134] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 11/12/2022] [Accepted: 11/13/2022] [Indexed: 11/18/2022] Open
Abstract
Plants are sessile organisms forced to adapt to environmental variations recurring in a day-night cycle. Extensive research has uncovered the transcriptional control of plants' inner clock and has revealed at least some part of the intricate and elaborate regulatory mechanisms that govern plant diel responses and provide adaptation to the ever-changing environment. Here, we analyzed the proteome of the Arabidopsis thaliana mutant genotypes collected in the middle of the day and the middle of the night, including four mutants in the phytochrome (phyA, phyB, phyC, and phyD) and the circadian clock protein LHY. Our approach provided a novel insight into the diel regulations, identifying 640 significant changes in the night-day protein abundance. The comparison with previous studies confirmed that a large portion of identified proteins was a known target of diurnal regulation. However, more than 300 were novel oscillations hidden under standard growth chamber conditions or not manifested in the wild type. Our results indicated a prominent role for ROS metabolism and phytohormone cytokinin in the observed regulations, and the consecutive analyses confirmed that. The cytokinin signaling significantly increased at night, and in the mutants, the hydrogen peroxide content was lower, and the night-day variation seemed to be lost in the phyD genotype. Furthermore, regulations in the lhy and phyB mutants were partially similar to those found in the catalase mutant cat2, indicating shared ROS-mediated signaling pathways. Our data also shed light on the role of the relatively poorly characterized Phytochrome D, pointing to its connection to glutathione metabolism and the regulation of glutathione S-transferases.
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6
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Vaishnav A, Kumar R, Singh HB, Sarma BK. Extending the benefits of PGPR to bioremediation of nitrile pollution in crop lands for enhancing crop productivity. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 826:154170. [PMID: 35227717 DOI: 10.1016/j.scitotenv.2022.154170] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 02/06/2022] [Accepted: 02/23/2022] [Indexed: 06/14/2023]
Abstract
Incessant release of nitrile group of compounds such as cyanides into agricultural land through industrial effluents and excessive use of nitrile pesticides has resulted in increased nitrile pollution. Release of nitrile compounds (NCs) as plant root exudates is also contributing to the problem. The released NCs interact with soil elements and persists for a long time. Persistent higher concentration of NCs in soil cause toxicity to beneficial microflora and affect crop productivity. The NCs can cause more problems to human health if they reach groundwater and enter the food chain. Nitrile degradation by soil bacteria can be a solution to the problem if thoroughly exploited. However, the impact of such bacteria in plant and soil environments is still not properly explored. Plant growth-promoting rhizobacteria (PGPR) with nitrilase activity has recently gained attention as potential solution to address the problem. This paper reviews the core issue of nitrile pollution in soil and the prospects of application of nitrile degrading bacteria for soil remediation, soil health improvement and plant growth promotion in nitrile-polluted soils. The possible mechanisms of PGPR that can be exploited to degrade NCs, converting them into plant useful compounds and synthesis of the phytohormone IAA from degraded NCs are also discussed at length.
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Affiliation(s)
- Anukool Vaishnav
- Department of Biotechnology, GLA University, Mathura 281406, India; Agroecology and Environment, Agroscope (Reckenholz), Zürich 8046, Switzerland
| | - Roshan Kumar
- National Centre for Biological Sciences (TIFR-NCBS), Bengaluru 560065, India
| | | | - Birinchi Kumar Sarma
- Department of Mycology and Plant Pathology, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi 221110, India.
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7
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Casanova-Sáez R, Mateo-Bonmatí E, Ljung K. Auxin Metabolism in Plants. Cold Spring Harb Perspect Biol 2021; 13:cshperspect.a039867. [PMID: 33431579 PMCID: PMC7919392 DOI: 10.1101/cshperspect.a039867] [Citation(s) in RCA: 78] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The major natural auxin in plants, indole-3-acetic acid (IAA), orchestrates a plethora of developmental responses that largely depend on the formation of auxin concentration gradients within plant tissues. Together with inter- and intracellular transport, IAA metabolism-which comprises biosynthesis, conjugation, and degradation-modulates auxin gradients and is therefore critical for plant growth. It is now very well established that IAA is mainly produced from Trp and that the IPyA pathway is a major and universally conserved biosynthetic route in plants, while other redundant pathways operate in parallel. Recent findings have shown that metabolic inactivation of IAA is also redundantly performed by oxidation and conjugation processes. An exquisite spatiotemporal expression of the genes for auxin synthesis and inactivation have been shown to drive several plant developmental processes. Moreover, a group of transcription factors and epigenetic regulators controlling the expression of auxin metabolic genes have been identified in past years, which are illuminating the road to understanding the molecular mechanisms behind the coordinated responses of local auxin metabolism to specific cues. Besides transcriptional regulation, subcellular compartmentalization of the IAA metabolism and posttranslational modifications of the metabolic enzymes are emerging as important contributors to IAA homeostasis. In this review, we summarize the current knowledge on (1) the pathways for IAA biosynthesis and inactivation in plants, (2) the influence of spatiotemporally regulated IAA metabolism on auxin-mediated responses, and (3) the regulatory mechanisms that modulate IAA levels in response to external and internal cues during plant development.
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Affiliation(s)
| | | | - Karin Ljung
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, SE-901 83 Umeå, Sweden
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8
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Jones LB, Wang X, Gullapalli JS, Kunz DA. Characterization of the Nit6803 nitrilase homolog from the cyanotroph Pseudomonas fluorescens NCIMB 11764. Biochem Biophys Rep 2021; 25:100893. [PMID: 33506113 PMCID: PMC7815647 DOI: 10.1016/j.bbrep.2020.100893] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 12/21/2020] [Accepted: 12/21/2020] [Indexed: 11/01/2022] Open
Abstract
We report the purification and characterization of a nitrilase (E.C. 3.5.5.1) (Nit11764) essential for the assimilation of cyanide as the sole nitrogen source by the cyanotroph, Pseudomonas fluorescens NCIMB 11764. Nit11764, is a member of a family of homologous proteins (nitrile_sll0784) for which the genes typically reside in a conserved seven-gene cluster known as Nit1C. The physical properties and substrate specificity of Nit11764 resemble those of Nit6803, the current reference protein for the family, and the only true nitrilase that has been crystallized. The substrate binding pocket of the two enzymes places the substrate in direct proximity to the active site nucleophile (C160) and conserved catalytic triad (Glu44, Lys126). The two enzymes exhibit a similar substrate profile, however, for Nit11764, cinnamonitrile, was found to be an even better substrate than fumaronitrile the best substrate previously identified for Nit6803. A higher affinity for cinnamonitrile (Km 1.27 mM) compared to fumaronitrile (Km 8.57 mM) is consistent with docking studies predicting a more favorable interaction with hydrophobic residues lining the binding pocket. By comparison, 3,4-dimethoxycinnamonitrile was a poorer substrate the substituted methoxyl groups apparently hindering entry into the binding pocket. in situ 1H NMR studies revealed that only one of the two nitrile substituents in the dinitrile, fumaronitrile, was attacked yielding trans-3-cyanoacrylate (plus ammonia) as a product. The essentiality of Nit11764 for cyanotrophy remains uncertain given that cyanide itself is a poor substrate and the catalytic efficiencies for even the best of nitrile substrates (~5 × 103 M-1 s-1) is less than stellar.
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Affiliation(s)
- Lauren B Jones
- Division of Biochemistry and Molecular Biology, Department of Biological Sciences, University of North Texas, Denton, TX, 76203, USA
| | - Xiaoqiang Wang
- Division of Biochemistry and Molecular Biology, Department of Biological Sciences, University of North Texas, Denton, TX, 76203, USA.,BioDiscovery Institute, Department of Biological Sciences, University of North Texas, Denton, TX, 76203, USA
| | - Jaya S Gullapalli
- Division of Biochemistry and Molecular Biology, Department of Biological Sciences, University of North Texas, Denton, TX, 76203, USA
| | - Daniel A Kunz
- Division of Biochemistry and Molecular Biology, Department of Biological Sciences, University of North Texas, Denton, TX, 76203, USA
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9
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Niehaus TD, Hillmann KB. Enzyme promiscuity, metabolite damage, and metabolite damage control systems of the tricarboxylic acid cycle. FEBS J 2020; 287:1343-1358. [DOI: 10.1111/febs.15284] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 02/26/2020] [Accepted: 03/05/2020] [Indexed: 12/11/2022]
Affiliation(s)
- Thomas D. Niehaus
- Department of Plant and Microbial Biology University of Minnesota Twin Cities Saint Paul MN USA
| | - Katie B. Hillmann
- Department of Plant and Microbial Biology University of Minnesota Twin Cities Saint Paul MN USA
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10
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Veiga‐da‐Cunha M, Van Schaftingen E, Bommer GT. Inborn errors of metabolite repair. J Inherit Metab Dis 2020; 43:14-24. [PMID: 31691304 PMCID: PMC7041631 DOI: 10.1002/jimd.12187] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 10/18/2019] [Accepted: 11/04/2019] [Indexed: 12/11/2022]
Abstract
It is traditionally assumed that enzymes of intermediary metabolism are extremely specific and that this is sufficient to prevent the production of useless and/or toxic side-products. Recent work indicates that this statement is not entirely correct. In reality, enzymes are not strictly specific, they often display weak side activities on intracellular metabolites (substrate promiscuity) that resemble their physiological substrate or slowly catalyse abnormal reactions on their physiological substrate (catalytic promiscuity). They thereby produce non-classical metabolites that are not efficiently metabolised by conventional enzymes. In an increasing number of cases, metabolite repair enzymes are being discovered that serve to eliminate these non-classical metabolites and prevent their accumulation. Metabolite repair enzymes also eliminate non-classical metabolites that are formed through spontaneous (ie, not enzyme-catalysed) reactions. Importantly, genetic deficiencies in several metabolite repair enzymes lead to 'inborn errors of metabolite repair', such as L-2-hydroxyglutaric aciduria, D-2-hydroxyglutaric aciduria, 'ubiquitous glucose-6-phosphatase' (G6PC3) deficiency, the neutropenia present in Glycogen Storage Disease type Ib or defects in the enzymes that repair the hydrated forms of NADH or NADPH. Metabolite repair defects may be difficult to identify as such, because the mutated enzymes are non-classical enzymes that act on non-classical metabolites, which in some cases accumulate only inside the cells, and at rather low, yet toxic, concentrations. It is therefore likely that many additional metabolite repair enzymes remain to be discovered and that many diseases of metabolite repair still await elucidation.
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Affiliation(s)
| | - Emile Van Schaftingen
- de Duve InstituteUniversité Catholique de Louvain (UCLouvain)BrusselsBelgium
- Walloon Excellence in Life Sciences and Biotechnology (WELBIO)UCLouvainBrusselsBelgium
| | - Guido T. Bommer
- de Duve InstituteUniversité Catholique de Louvain (UCLouvain)BrusselsBelgium
- Walloon Excellence in Life Sciences and Biotechnology (WELBIO)UCLouvainBrusselsBelgium
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11
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Rendu J, Van Noolen L, Garrel C, Brocard J, Marty I, Corne C, Fauré J, Besson G. Familial deep cavitating state with a glutathione metabolism defect. Ann Clin Transl Neurol 2019; 6:2573-2578. [PMID: 31705625 PMCID: PMC6917305 DOI: 10.1002/acn3.50933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 10/08/2019] [Accepted: 10/09/2019] [Indexed: 11/07/2022] Open
Abstract
Adult genetic disorders causing brain lesions have been mostly described as white matter vanishing diseases. We present here the investigations realized in patients referred for psychiatric disorder with magnetic resonance imaging showing atypical basal ganglia lesions. Genetic explorations of this family revealed a new hereditary disease linked to glutathione metabolism.
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Affiliation(s)
- John Rendu
- Univ. Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut Neurosciences, 38000, Grenoble, France
| | | | | | - Julie Brocard
- Univ. Grenoble Alpes, Inserm, U1216, Grenoble Institut des Neurosciences, 38000, Grenoble, France
| | - Isabelle Marty
- Univ. Grenoble Alpes, Inserm, U1216, Grenoble Institut des Neurosciences, 38000, Grenoble, France
| | | | - Julien Fauré
- Univ. Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut Neurosciences, 38000, Grenoble, France
| | - Gérard Besson
- Department of Neurology, CHU, Grenoble Alpes, 38000, Grenoble, France
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12
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Plant nitrilase: a new job for an old enzyme. Biochem J 2019; 476:1105-1107. [PMID: 30971459 DOI: 10.1042/bcj20190060] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 03/26/2019] [Accepted: 03/26/2019] [Indexed: 11/17/2022]
Abstract
Nitrilases are versatile enzymes that hydrolyze nitriles to carboxylic acids and ammonia, but many members of this family lack defined biological functions. In plants, nitrilases have been associated with detoxification of cyanide-containing compounds and auxin biosynthesis; however, recent work suggests that the chemical versatility of these proteins contributes to metabolite repair. In this issue of the Biochemical Journal, Niehaus et al. demonstrate that the Nit1 nitrilase from Arabidopsis thaliana functions as a metabolite repair enzyme that removes deaminated glutathione from the cytoplasm and plastids.
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