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Chin T, Okuda Y, Ikeuchi M. Sorbitol production and optimization of photosynthetic supply in the cyanobacterium Synechocystis PCC 6803. J Biotechnol 2018; 276-277:25-33. [PMID: 29684388 DOI: 10.1016/j.jbiotec.2018.04.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 03/20/2018] [Accepted: 04/10/2018] [Indexed: 11/15/2022]
Abstract
Biochemicals production is a major theme in the application of photosynthesis to address global warming and organic-resource problems. Among biochemicals, sugar alcohols have attracted research attention because they are directly derived from two photosynthetic products, sugars and reductants. Here, we produced sorbitol photosynthetically by using cyanobacteria and modified the supply of its substrates through genetic engineering. Expression of an NADPH-dependent enzyme that generates sorbitol-6-phosphate, S6PDH, was highly toxic to cyanobacteria likely due to the sorbitol production, whereas expression of an NADH-dependent enzyme, SrlD2, yielded no sorbitol. The toxicity was partly overcome by introducing a theophylline-inducible riboswitch for S6PDH expression and optimizing induction, but sorbitol production was still low and severely inhibited growth. Co-expression of fructose-1,6-bisphosphatase drastically alleviated the growth inhibition, but did not increase short-term sorbitol production. The NADPH/NADP+ ratio decreased during sorbitol production. Overexpression of a membrane-bound transhydrogenase for NADPH generation from NADH elevated the short-term sorbitol production, but only partly alleviated the growth inhibition. Notably, a strain overexpressing all three enzymes exhibited sustainable sorbitol production at 312 mg/L, which was nearly 27-fold higher than the yield of the initial S6PDH-overexpressing strain. We discuss these results in relation to the optimization of photosynthetic supply for sorbitol production in cyanobacteria.
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Affiliation(s)
- Taejun Chin
- Department of Life Sciences (Biolgy), Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan
| | - Yukiko Okuda
- Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan
| | - Masahiko Ikeuchi
- Department of Life Sciences (Biolgy), Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan; Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan.
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2
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Ghaffari MR, Shahinnia F, Usadel B, Junker B, Schreiber F, Sreenivasulu N, Hajirezaei MR. The Metabolic Signature of Biomass Formation in Barley. PLANT & CELL PHYSIOLOGY 2016; 57:1943-60. [PMID: 27388338 DOI: 10.1093/pcp/pcw117] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2016] [Accepted: 06/16/2016] [Indexed: 05/18/2023]
Abstract
The network analysis of genome-wide transcriptome responses, metabolic signatures and enzymes' relationship to biomass formation has been studied in a diverse panel of 12 barley accessions during vegetative and reproductive stages. The primary metabolites and enzymes involved in central metabolism that determine the accumulation of shoot biomass at the vegetative stage of barley development are primarily being linked to sucrose accumulation and sucrose synthase activity. Interestingly, the metabolic and enzyme links which are strongly associated with biomass accumulation during reproductive stages are related to starch accumulation and tricarboxylic acid (TCA) cycle intermediates citrate, malate, trans-aconitate and isocitrate. Additional significant associations were also found for UDP glucose, ATP and the amino acids isoleucine, valine, glutamate and histidine during the reproductive stage. A network analysis resulted in a combined identification of metabolite and enzyme signatures indicative for grain weight accumulation that was correlated with the activity of ADP-glucose pyrophosphorylase (AGPase), a rate-limiting enzyme involved in starch biosynthesis, and with that of alanine amino transferase involved in the synthesis of storage proteins. We propose that the mechanism related to vegetative and reproductive biomass formation vs. seed biomass formation is being linked to distinct fluxes regulating sucrose, starch, sugars and amino acids as central resources. These distinct biomarkers can be used to engineer biomass production and grain weight in barley.
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Affiliation(s)
- Mohammad R Ghaffari
- Agricultural Biotechnology Research Institute of Iran (ABRII), Agricultural Research, Education and Extension Organization (AREO), Tehran, Iran Leibniz Institute of Plant Genetics and Crop Plant Research, Corrensstraße 3, D-06466 Gatersleben, Germany
| | - Fahimeh Shahinnia
- Leibniz Institute of Plant Genetics and Crop Plant Research, Corrensstraße 3, D-06466 Gatersleben, Germany
| | - Björn Usadel
- Institute of Botany, RWTH Aachen University, BioSC Germany and IBG-2 Plant Sciences, Forschungszentrum Jülich, D-52428 Jülich, Germany
| | - Björn Junker
- Institute of Pharmacy/Biosynthesis of Active Substances, Hoher Weg 8, Halle (Saale), Germany
| | - Falk Schreiber
- Monash University, Clayton Campus, Wellington Road, Clayton, VIC 3800, Australia
| | - Nese Sreenivasulu
- International Rice Research Institute, DAPO Box 7777, Metro Manila, Philippines
| | - Mohammad R Hajirezaei
- Leibniz Institute of Plant Genetics and Crop Plant Research, Corrensstraße 3, D-06466 Gatersleben, Germany
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Feng L, Sun Y, Deng H, Li D, Wan J, Wang X, Wang W, Liao X, Ren Y, Hu X. Structural and biochemical characterization of fructose-1,6/sedoheptulose-1,7-bisphosphatase from the cyanobacterium Synechocystis strain 6803. FEBS J 2013; 281:916-26. [PMID: 24286336 DOI: 10.1111/febs.12657] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 11/22/2013] [Accepted: 11/25/2013] [Indexed: 12/01/2022]
Abstract
Cyanobacterial fructose-1,6/sedoheptulose-1,7-bisphosphatase (cy-FBP/SBPase) plays a vital role in gluconeogenesis and in the photosynthetic carbon reduction pathway, and is thus a potential enzymatic target for inhibition of harmful cyanobacterial blooms. Here, we describe the crystal structure of cy-FBP/SBPase in complex with AMP and fructose-1,6-bisphosphate (FBP). The allosteric inhibitor AMP and the substrate FBP exhibit an unusual binding mode when in complex with cy-FBP/SBPase. Binding mode analysis suggested that AMP bound to the allosteric sites near the interface across the up/down subunit pairs C1C4 and C2C3 in the center of the tetramer, while FBP binds opposite to the interface between the horizontal subunit pairs C1C2 or C3C4. We identified a series of residues important for FBP and AMP binding, and suggest formation of a disulfide linkage between Cys75 and Cys99. Further analysis indicates that cy-FBP/SBPase may be regulated through ligand binding and alteration of the structure of the enzyme complex. The interactions between ligands and cy-FBP/SBPase are different from those of ligand-bound structures of other FBPase family members, and thus provide new insight into the molecular mechanisms of structure and catalysis of cy-FBP/SBPase. Our studies provide insight into the evolution of this enzyme family, and may help in the design of inhibitors aimed at preventing toxic cyanobacterial blooms.
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Affiliation(s)
- Lingling Feng
- Key Laboratory of Pesticide & Chemical Biology (CCNU), Ministry of Education, and College of Chemistry, Central China Normal University, Wuhan, 430079, China
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4
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Lepistö A, Kangasjärvi S, Luomala EM, Brader G, Sipari N, Keränen M, Keinänen M, Rintamäki E. Chloroplast NADPH-thioredoxin reductase interacts with photoperiodic development in Arabidopsis. PLANT PHYSIOLOGY 2009; 149:1261-76. [PMID: 19151130 PMCID: PMC2649390 DOI: 10.1104/pp.108.133777] [Citation(s) in RCA: 122] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2008] [Accepted: 01/13/2009] [Indexed: 05/18/2023]
Abstract
Chloroplast NADPH-thioredoxin reductase (NTRC) belongs to the thioredoxin systems that control crucial metabolic and regulatory pathways in plants. Here, by characterization of T-DNA insertion lines of NTRC gene, we uncover a novel connection between chloroplast thiol redox regulation and the control of photoperiodic growth in Arabidopsis (Arabidopsis thaliana). Transcript and metabolite profiling revealed severe developmental and metabolic defects in ntrc plants grown under a short 8-h light period. Besides reduced chlorophyll and anthocyanin contents, ntrc plants showed alterations in the levels of amino acids and auxin. Furthermore, a low carbon assimilation rate of ntrc leaves was associated with enhanced transpiration and photorespiration. All of these characteristics of ntrc were less severe when plants were grown under a long 16-h photoperiod. Transcript profiling revealed that the mutant phenotypes of ntrc were accompanied by differential expression of genes involved in stomatal development, chlorophyll biosynthesis, chloroplast biogenesis, and circadian clock-linked light perception systems in ntrc plants. We propose that NTRC regulates several key processes, including chlorophyll biosynthesis and the shikimate pathway, in chloroplasts. In the absence of NTRC, imbalanced metabolic activities presumably modulate the chloroplast retrograde signals, leading to altered expression of nuclear genes and, ultimately, to the formation of the pleiotrophic phenotypes in ntrc mutant plants.
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Affiliation(s)
- Anna Lepistö
- Department of Biology, University of Turku, FI-20014 Turku, Finland
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Ahkami AH, Lischewski S, Haensch KT, Porfirova S, Hofmann J, Rolletschek H, Melzer M, Franken P, Hause B, Druege U, Hajirezaei MR. Molecular physiology of adventitious root formation in Petunia hybrida cuttings: involvement of wound response and primary metabolism. THE NEW PHYTOLOGIST 2009; 181:613-25. [PMID: 19076299 DOI: 10.1111/j.1469-8137.2008.02704.x] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Adventitious root formation (ARF) in the model plant Petunia hybrida cv. Mitchell has been analysed in terms of anatomy, gene expression, enzymatic activities and levels of metabolites. This study focuses on the involvement of wound response and primary metabolism. Microscopic techniques were complemented with targeted transcript, enzyme and metabolite profiling using real time polymerase chain reaction (PCR), Northern blot, enzymatic assays, chromatography and mass spectrometry. Three days after severance from the stock plants, first meristematic cells appeared which further developed into root primordia and finally adventitious roots. Excision of cuttings led to a fast and transient increase in the wound-hormone jasmonic acid, followed by the expression of jasmonate-regulated genes such as cell wall invertase. Analysis of soluble and insoluble carbohydrates showed a continuous accumulation during ARF. A broad metabolite profiling revealed a strong increase in organic acids and resynthesis of essential amino acids. Substantial changes in enzyme activities and metabolite levels indicate that specific enzymes and metabolites might play a crucial role during ARF. Three metabolic phases could be defined: (i) sink establishment phase characterized by apoplastic unloading of sucrose and being probably mediated by jasmonates; (ii) recovery phase; and (iii) maintenance phase, in which a symplastic unloading occurs.
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Affiliation(s)
- Amir H Ahkami
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, Germany
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Jang HK, Lee SW, Lee YH, Hahn TR. Purification and characterization of a recombinant pea cytoplasmic fructose-1,6-bisphosphatase. Protein Expr Purif 2003; 28:42-8. [PMID: 12651105 DOI: 10.1016/s1046-5928(02)00654-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Full-length cDNA encoding pea cytoplasmic fructose-1,6-bisphosphatase (cyFBPase) was cloned from a pea cDNA library. The cloned cDNA was introduced into the Escherichia coli expression vector pET-15b. The recombinant cyFBPase was expressed in E. coli BL21 (DE3) cells in a soluble form and purified to homogeneity by Ni(+)-NTA affinity chromatography. The identity of the recombinant cyFBPase was confirmed by SDS-PAGE and immunoblot analysis using a polyclonal anti-His tag antibody. The recombinant cyFBPase was active at neutral pH ranges (6.6-9.0) and thermostable as other cyFBPases. The activation energy (E(a)) and Arrhenius frequency factor were 17.4 kcal/mol and 2.6 x 10(12)/s, respectively. The K(M) and V(max) values of the recombinant enzyme were calculated as 10.47 microM and 109 micromol/min, respectively. In case of removal of histidine tag, the K(M) value was calculated as 5.03 microM. The recombinant enzyme was non-competitively and competitively inhibited by AMP and fructose-2,6-bisphosphate, respectively.
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Affiliation(s)
- Hye-Kyung Jang
- Plant Metabolism Research Center (PMRC) and Graduate School of Biotechnology, Kyung Hee University, Suwon 449-701, Republic of Korea
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Tang GL, Wang YF, Bao JS, Chen HB. Overexpression in Escherichia coli and characterization of the chloroplast fructose-1,6-bisphosphatase from wheat. Protein Expr Purif 2000; 19:411-8. [PMID: 10910732 DOI: 10.1006/prep.2000.1267] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
An important Calvin cycle enzyme, chloroplast fructose-1, 6-bisphosphatase (FBPase) from wheat, has been cloned and expressed up to 15% of the total cell protein using a pPLc expression vector in Escherichia coli by replacing the codons in the 5'-terminal encoding sequence with optimal and A/T-rich ones. The overexpressed wheat FBPase is soluble, fully active, and heat stable. It can be purified by chromatography in turn on DEAE-Sepharose and Sephacryl S-200, and around 15 mg of purified enzymes (>95%) is obtained from 1 liter of cultured bacteria. Its special activity is 8.8 u/mg, K(cat) is 22.9/S, K(m) is 121 microM, and V(max) is 128 micromol/min. mg. The recombinant FBPase can be activated by DTT, Na(+), or low concentrations of Li(+), Ca(2+), Zn(2+), GuHCl, and urea, while it can be inhibited by K(+) or NH(+)(4).
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Affiliation(s)
- G L Tang
- State Key Laboratory of Bio-organic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Feng Lin Lu, Shanghai, 200032, People's Republic of China
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Tamoi M, Murakami A, Takeda T, Shigeoka S. Acquisition of a new type of fructose-1,6-bisphosphatase with resistance to hydrogen peroxide in cyanobacteria: molecular characterization of the enzyme from Synechocystis PCC 6803. BIOCHIMICA ET BIOPHYSICA ACTA 1998; 1383:232-44. [PMID: 9602137 DOI: 10.1016/s0167-4838(97)00208-2] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
We have previously described that Synechococcus PCC 7942 cells contain two fructose-1,6-bisphosphatase isozymes, designated F-I and F-II the former belongs to a new type of fructose-1,6-bisphosphatase, while the latter is a typical enzyme similar to the cytosolic and chloroplastic forms from eukaryotic cells [Tamoi et al., Arch. Biochem. Biophys., 334, 1996, 27-36]. The genes of F-I and F-II were found in three species of cyanobacteria, Synechocystis PCC 6803, Anabaena 7120, and Plectonema boryanum according to the results of Southern hybridization with a probe from the S. 7942 F-I and F-II genes. In Western blotting, antibody raised against the S. 7942 F-I cross-reacted with a protein band corresponding to the F-I in each crude extract from cyanobacterial cells, whereas the antibody against F-II failed to cross-react with any protein band corresponding to the F-II. In cyanobacterial cells, only one form of F-I has been resolved by ion-exchange chromatography at same concentration of NaCl as shown in the F-I of S. 7942. The F-I from Synechocystis 6803 has been purified to electrophoretic homogeneity. The enzyme hydrolyzed both fructose 1,6-bisphosphate and sedoheptulose 1,7-bisphosphate. The apparent K(m) values of the enzyme for fructose 1,6-bisphosphate and sedoheptulose 1,7-bisphosphate were 57 +/- 2.4 and 180 +/- 6.3 microM, respectively. The enzyme activity was inhibited by AMP with a Ki value of 0.57 +/- 0.03 mM for fructose 1,6-bisphosphate and 0.35 +/- 0.02 mM for sedoheptulose 1,7-bisphosphate. The enzyme showed a molecular mass of 168 kDa which was composed of four identical subunits. The activities of FBPase and SBPase from the F-I were resistant to hydrogen peroxide up to 1 mM. The nucleotide sequence of the S. 6803 F-I gene showed an open reading frame of 1164 bp that encoded a protein of 388 amino acid residues (approx. molecular mass of 41.6 kDa). The deduced amino acid sequences had homologous sequences with the S. 7942 F-I.
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Affiliation(s)
- M Tamoi
- Department of Food and Nutrition, Faculty of Agriculture, Kinki University, Nara, Japan
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Rodriguez-Suarez RJ, Wolosiuk RA. High level expression in Escherichia coli, purification and properties of chloroplast fructose-1,6-bisphosphatase from rapeseed (Brassica napus) leaves. PHOTOSYNTHESIS RESEARCH 1995; 46:313-322. [PMID: 24301598 DOI: 10.1007/bf00020446] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/1995] [Accepted: 06/13/1995] [Indexed: 06/02/2023]
Abstract
In chloroplasts, the light-modulated fructose-1,6-bisphosphatase catalyzes the formation of fructose 6-bisphosphate for the photosynthetic assimilation of CO2 and the biosynthesis of starch. We report here the construction of a plasmid for the production of chloroplast fructose-1,6-bisphosphatase in a bacterial system and the subsequent purification to homogeneity of the genetically engineered enzyme. To this end, a DNA sequence that coded for chloroplast fructose-1,6-bisphosphatase of rapeseed (Brassica napus) leaves was successively amplified by PCR, ligated into the Ndel/EcoRI restriction site of the expression vector pET22b, and introduced into Escherichia coli cells. When gene expression was induced by isopropyl-β-D-thiogalactopyranoside, supernatants of cell lysates were extremely active in the hydrolysis of fructose 1,6-bisphosphate. Partitioning bacterial soluble proteins by ammonium sulfate followed by anion exchange chromatography yielded 10 mg of homogeneous enzyme per 1 of culture. Congruent with a preparation devoid of contaminating proteins, the Edman degradation evinced an unique N-terminal amino acid sequence [A-V-A-A-D-A-T-A-E-T-K-P-]. Gel filtration experiments and sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicated that the (recombinant) rapeseed chloroplast fructose-1,6-bisphosphatases was a tetramer [160 kDa] comprised of four identical subunits. Like other chloroplast fructose-1,6-bisphosphatases, the recombinant enzyme was inactive at 1 mM fructose 1,6-bisphosphate and 1 mM Mg(2+) but became fully active after an incubation in the presence of either 10 mM dithiothreitol or 1 mM dithiothreitol and chloroplast thioredoxin. However, at variance with counterparts isolated from higher plant leaves, the low activity observed in absence of reductants was not greatly enhanced by high concentrations of fructose 1,6-bisphosphate (3 mM) and Mg(2+) (10 mM). In the catalytic process, all chloroplast fructose-1,6-bisphosphatases had identical features; viz., the requirement of Mg(2+) as cofactor and the inhibition by Ca(2+). Thus, the procedure described here should prove useful for the structural and kinetic analysis of rapeseed chloroplast fructose-1,6-bisphosphatase in view that this enzyme was not isolated from leaves.
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Affiliation(s)
- R J Rodriguez-Suarez
- Instituto de Investigaciones Bioquímicas (Fundación Campomar, IIBBA-CONICET, FCEN-UBA), Antonio Machado 151, 1405, Buenos Aires, Argentina
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Daie J. Cytosolic fructose-1,6-bisphosphatase: A key enzyme in the sucrose biosynthetic pathway. PHOTOSYNTHESIS RESEARCH 1993; 38:5-14. [PMID: 24317825 DOI: 10.1007/bf00015056] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/1993] [Accepted: 06/29/1993] [Indexed: 05/05/2023]
Abstract
Fructose-1,6 bisphosphatase (FBPase) is a ubiquitous enzyme controlling a key reaction. In non-photosynthetic tissues, it regulates the rate of gluconeogenesis. In photosynthetic tissues, two FBPase isozymes (chloroplastic and cytosolic) play key roles in carbon assimilation and metabolism. The cytosolic FBPase is one of the regulatory enzymes in the sucrose biosynthetic pathway - its activity is regulated by both fine and coarse control mechanisms. Kinetic and allosteric properties of the plant cytosolic FBPase are remarkably similar to the mammalian and yeast FBPase, but differ greatly from those of the chloroplastic FBPase. Cytosolic FBPase is relatively conserved among various organisms both at amino acid and nucleotide sequence levels. There is slightly higher similarity between mammalian FBPase and plant cytosolic FBPase than there is between the two plant FBPases. Expression of plant cytosolic FBPase gene is developmentally regulated and appears to be coordinated with the expression of Rubisco and other carbon metabolism enzymes. Similar to the gluconeogenic FBPase, relatively rapid end product repression of FBPase gene occurs in plant. However, unlike the gluconeogenic FBPase, a concurrent decline in plant FBPase activity does not occur in response to increased end product levels. The physiological significance of FBPase gene repression, therefore, remains unclear in plants. Both expression and activity of the cytosolic FBPase are regulated by environmental factors such as light and drought conditions. Light-dependent modulation of FBPase activity in plants appears to involve some type of posttranslational modification. In addition to elucidating the exact nature of the presumed posttranslational modification, cloning of genomic and upstream sequences is needed before we fully understand the molecular regulation of the cytosolic FBPase in plants. Use of transgenic plants with altered rates of FBPase activity offers potential for enhanced crop productivity.
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Affiliation(s)
- J Daie
- Department of Botany, University of Wisconsin, Birge Hall, 53706, Madison, WI, USA
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Abstract
The activity of crude and pure enzyme preparations as well as the molecular weight of these enzymes were obtained from the literature for several organisms. From these data enzyme concentrations were calculated and compared to the concentration(s) of their substrates in the same organism. The data are expressed as molar ratios of metabolite concentration to enzyme site concentration. Of the 140 ratios calculated, 88% were one or greater, indicating that in general substrates exceed their cognate enzyme concentrations. Of the 17 cases where enzyme exceeds metabolite concentration, 16 were in glycolysis. The data in general justify the use of enzyme kinetic mechanisms determined in vitro in the construction of dynamic models which simulate in vivo metabolism.
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Affiliation(s)
- K R Albe
- Microbiology Department, University of Montana, Missoula 59812
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Raines CA, Lloyd JC, Longstaff M, Bradley D, Dyer T. Chloroplast fructose-1,6-bisphosphatase: the product of a mosaic gene. Nucleic Acids Res 1988; 16:7931-42. [PMID: 2843806 PMCID: PMC338501 DOI: 10.1093/nar/16.16.7931] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
We show here that light stimulates the expression of nuclear genes in wheat leaves for chloroplast fructose-1,6-bisphosphatase (FBPase) and describe a sequence of amino acids in this enzyme which may be responsible, via thioredoxin, for the light regulation of its activity. This data results from (a) our isolation and characterization of a cDNA of this enzyme which contains its entire coding sequence, and (b) our use of this cDNA as a probe to detect mRNA levels in wheat plants subjected to different light regimes. The similarity in amino acid sequence of the encoded enzyme from diverse sources suggests that the FBPase genes all had a common origin. However, their control sequences have been adjusted so that they are appropriately expressed and their coding sequences modified so that the enzymic activity of their products are suitably regulated in the particular cellular environment in which they must function. The light-activated regulatory sequences in the gene for the chloroplast protein have probably come together by a shuffling of DNA segments.
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Affiliation(s)
- C A Raines
- Institute of Plant Science Research, Cambridge Laboratory, UK
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Marcus F, Moberly L, Latshaw SP. Comparative amino acid sequence of fructose-1,6-bisphosphatases: identification of a region unique to the light-regulated chloroplast enzyme. Proc Natl Acad Sci U S A 1988; 85:5379-83. [PMID: 2840657 PMCID: PMC281760 DOI: 10.1073/pnas.85.15.5379] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Chloroplast fructose-1,6-bisphosphatase (Fru-P2-ase) is an essential enzyme in the photosynthetic pathway of carbon dioxide fixation into sugars. The properties of the chloroplast enzyme are clearly distinct from cytosolic gluconeogenic Fru-P2-ases. Light-dependent activation by way of a ferredoxin/thioredoxin system and insensitivity to AMP inhibition are distinctive characteristics of the chloroplast enzyme. However, the chloroplast enzyme shows a high degree of amino acid sequence similarity to gluconeogenic Fru-P2-ases. Sequence data reported for a total of 285 residues (approximately 75% of the structure) of the spinach chloroplast enzyme reveals a 46% amino acid sequence identity with pig kidney Fru-P2-ase. We now report the amino acid sequence of a region consisting of 46 additional residues. This region is located near the middle of the primary structure of the enzyme and it includes a 16-residue insert not present in other Fru-P2-ases. This sequence insert has two cysteines separated by only 4 amino acid residues (Cys-Val-Val-Asn-Val-Cys), a characteristic feature of at least three other enzymes containing redox-active cysteines. It appears likely that this region of chloroplast Fru-P2-ase is involved in light-dependent activation.
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Affiliation(s)
- F Marcus
- Department of Biological Chemistry and Structure, University of Health Sciences, Chicago Medical School, IL 60064
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14
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Kreimer G, Melkonian M, Holtum JA, Latzko E. Characterization of calcium fluxes across the envelope of intact spinach chloroplasts. PLANTA 1985; 166:515-523. [PMID: 24241617 DOI: 10.1007/bf00391276] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/1985] [Accepted: 06/17/1985] [Indexed: 06/02/2023]
Abstract
Calcium fluxes across the envelope of intact spinach chloroplasts (Spinacia oleracea L.) in the light and in the dark were investigated using the metallochromic indicator arsenazo III. Light induces Ca(2+) influx into chloroplasts. The action spectrum of light-induced Ca(2+) influx and the inhibitory effect of 3-(3',4'-dichlorophenyl)-1,1-dimethylurea (DCMU) indicate an involement of photosynthetic electron transport in this process. The driving force for light-induced Ca(2+) influx is most likely a change in the membrane potential component of the proton motive force. This was demonstrated by the use of agents modifying the membrane potential (lipophilic cations, ionophores, different KCl concentrations). The activation energy of the observed Ca(2+) influx is about 92 kJ mol(-1). Verapamil and nifedipine, two Ca(2+)-channel blockers, have no inhibitory effect on light-induced Ca(2+) influx, but enhance ferricyanide-dependent oxygen evolution. Inhibition of Ca(2+) influx by ruthenium red reduces the light-dependent decrease in stromal NAD(+) level.
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Affiliation(s)
- G Kreimer
- Botanisches Institut der Westfälischen Wilhelms-Universität, Schloßgarten 3, D-4400, Münster, Federal Republic of Germany
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15
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The Regulation of Cytoplasmic Fructose 1,6-bisphosphatase in Relation to the Control of Carbon Flow to Sucrose. ACTA ACUST UNITED AC 1982. [DOI: 10.1016/s0044-328x(82)80147-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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