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Milagros Medina - One of the best experts on this subject based on the ideXlab platform.
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Human Riboflavin Kinase: Species-specific traits in the biosynthesis of the FMN cofactor.
The FASEB Journal, 2020Co-Authors: Ernesto Anoz-carbonell, Adrián Velázquez-campoy, Maribel Rivero, Victor Polo, Milagros MedinaAbstract:Human Riboflavin Kinase (HsRFK) catalyzes vitamin B2 (Riboflavin) phosphorylation to flavin mononucleotide (FMN), obligatory step in flavin cofactor synthesis. HsRFK expression is related to protection from oxidative stress, amyloid-β toxicity, and some malignant cancers progression. Its downregulation alters expression profiles of clock-controlled metabolic-genes and destroys flavins protection on stroke treatments, while its activity reduction links to protein-energy malnutrition and thyroid hormones decrease. We explored specific features of the mechanisms underlying the regulation of HsRFK activity, showing that both reaction products regulate it through competitive inhibition. Fast-kinetic studies show that despite HsRFK binds faster and preferably the reaction substrates, the complex holding both products is kinetically most stable. An intricate ligand binding landscape with all combinations of substrates/products competing with the catalytic complex and exhibiting moderate cooperativity is also presented. These data might contribute to better understanding the molecular bases of pathologies coursing with aberrant HsRFK availability, and envisage that interaction with its client-apoproteins might favor FMN release. Finally, HsRFK parameters differ from those of the so far evaluated bacterial counterparts, reinforcing the idea of species-specific mechanisms in RFK catalysis. These observations support HsRFK as potential therapeutic target because of its key functions, while also envisage bacterial RFK modules as potential antimicrobial targets.
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Specific Features for the Competent Binding of Substrates at the FMN Adenylyltransferase Site of FAD Synthase from Corynebacterium ammoniagenes.
International Journal of Molecular Sciences, 2019Co-Authors: Sonia Arilla-luna, Ana Serrano, Milagros MedinaAbstract:Bifunctional FAD synthases (FADSs) catalyze FMN (flavin mononucleotide) and FAD (flavinadenine dinucleotide) biosynthesis at their C-Riboflavin Kinase (RFK) and N-FMN:adenylyltransferase (FMNAT) modules, respectively. Biophysical properties and requirements for their FMNAT activity differ among species. Here, we evaluate the relevance of the integrity of the binding site of the isoalloxazine of flavinic substrates for FMNAT catalysis in Corynebacterium ammoniagenes FADS (CaFADS). We have substituted P56 and P58, belonging to a conserved motif, as well as L98. These residues shape the isoalloxazine FMNAT site, although they are not expected to directly contact it. All substitutions override enzyme ability to transform substrates at the FMNAT site, although most variants are able to bind them. Spectroscopic properties and thermodynamic parameters for the binding of ligands indicate that mutations alter their interaction modes. Substitutions also modulate binding and kinetic properties at the RFK site, evidencing the crosstalk of different protomers within CaFADS assemblies during catalysis. In conclusion, despite the FMNAT site for the binding of substrates in CaFADS appearing as a wide open cavity, it is finely tuned to provide the competent binding conformation of substrates. In particular, P56, P58 and L98 shape the isoalloxazine site to place the FMN- and FAD-reacting phosphates in optimal geometry for catalysis.
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The Biosynthesis of Flavin Cofactors in Listeria monocytogenes.
Journal of Molecular Biology, 2019Co-Authors: María Sebastián, Sonia Arilla-luna, Jacques Bellalou, Inmaculada Yruela, Milagros MedinaAbstract:Listeria monocytogenes is Riboflavin auxotrophic, but it has two genes envisaged to transform Riboflavin into FMN and FAD after its uptaked by specialized transporters. One encodes a bifunctional type I FAD synthase (FADS, herein LmFADS-1), while the other produces a protein similar to type I at the FMN:ATP adenylyltransferase (FMNAT) site but with a shorter C-terminal that lacks any Riboflavin Kinase (RFK) motif. This second protein is rare among bacteria and has been named FADS type II (LmFADS-2). Here we present a biochemical and biophysical study of LmFADS-1 and LmFADS-2 by integrating kinetic and thermodynamic data together with sequence and structural prediction methods to evaluate their occurrence in Listeria, as well as their function and molecular properties. Despite LmFADS-1 similarities to other type I FADSs, (i) its RFK activity has not Riboflavin substrate inhibition and occurs under reducing and oxidizing conditions, (ii) its FMNAT activity requires strong reducing environment, and (iii) binding of reaction products, but not substrates, favors binding of the second ligand. LmFADS-2 produces FAD under oxidizing and reducing environments, but its C-terminus module function remains unknown. Listeria species conserve both FADSs, being sequence identity high within L. monocytogenes strains. Our data exemplify alternative strategies for FMN and FAD biosynthesis and homeostasis, envisaging that in Listeria two FADSs might be required to fulfill the supply of flavin cofactors under niches that can go from saprophytism to virulence. As FADSs are attractive antimicrobial targets, understanding of FADSs traits in different species is essential to help in the discovery of specific antimicrobials.
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The RFK catalytic cycle of the pathogen Streptococcus pneumoniae shows species-specific features in prokaryotic FMN synthesis.
Journal of Enzyme Inhibition and Medicinal Chemistry, 2018Co-Authors: María Sebastián, Adrián Velázquez-campoy, Milagros MedinaAbstract:AbstractEmergence of multidrug-resistant bacteria forces us to explore new therapeutic strategies, and proteins involved in key metabolic pathways are promising anti-bacterial targets. Bifunctional flavin-adenine dinucleotide (FAD) synthetases (FADS) are prokaryotic enzymes that synthesise the flavin mononucleotide (FMN) and FAD cofactors. The FADS from the human pathogen Streptococcus pneumoniae (SpnFADS)–causative agent of pneumonia in humans − shows relevant catalytic dissimilarities compared to other FADSs. Here, by integrating thermodynamic and kinetic data, we present a global description of the Riboflavin Kinase activity of SpnFADS, as well as of the inhibition mechanisms regulating this activity. Our data shed light on biophysical determinants that modulate species-specific conformational changes leading to catalytically competent conformations, as well as binding rates and affinities of substrates versus products. This knowledge paves the way for the development of tools − that taking advantage o...
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The Dimer-of-Trimers Assembly Prevents Catalysis at the Transferase Site of Prokaryotic FAD Synthase.
Biophysical Journal, 2018Co-Authors: Isaias Lans, Ana Serrano, Juan Seco, Ricardo Burbano, Pilar Cossio, Martha C. Daza, Milagros MedinaAbstract:Abstract Flavin mononucleotide (FMN) and flavin-adenine dinucleotide (FAD) are essential flavoprotein cofactors. A Riboflavin Kinase (RFK) activity catalyzes Riboflavin phosphorylation to FMN, which can then be transformed into FAD by an FMN:adenylyltransferase (FMNAT) activity. Two enzymes are responsible for each one of these activities in eukaryotes, whereas prokaryotes have a single bifunctional enzyme, FAD synthase (FADS). FADS folds in two independent modules: the C-terminal with RFK activity and the N-terminal with FMNAT activity. Differences in structure and chemistry for the FMNAT catalysis among prokaryotic and eukaryotic enzymes pointed to the FMNAT activity of prokaryotic FADS as a potential antimicrobial target, making the structural model of the bacterial FMNAT module in complex with substrates relevant to understand the FADS catalytic mechanism and to the discovery of antimicrobial drugs. However, such a crystallographic complex remains elusive. Here, we have used molecular docking and molecular dynamics simulations to generate energetically stable interactions of the FMNAT module of FADS from Corynebacterium ammoniagenes with ATP/Mg2+ and FMN in both the monomeric and dimer-of-trimers assemblies reported for this protein. For the monomer, we have identified the residues that accommodate the reactive phosphates in a conformation compatible with catalysis. Interestingly, for the dimer-of-trimers conformation, we have found that the RFK module negatively influences FMN binding at the interacting FMNAT module. These results agree with calorimetric data of purified samples containing nearly 100% monomer or nearly 100% dimer-of-trimers, indicating that FMN binds to the monomer but not to the dimer-of-trimers. Such observations support regulation of flavin homeostasis by quaternary C. ammoniagenes FADS assemblies.
Andriy A Sibirny - One of the best experts on this subject based on the ideXlab platform.
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medium optimization for production of flavin mononucleotide by the recombinant strain of the yeast candida famata using statistical designs
Biochemical Engineering Journal, 2010Co-Authors: Valentyna Y Yatsyshyn, Daria V Fedorovych, Andriy A SibirnyAbstract:Abstract The recombinant strain of the yeast Candida famata 13-76 that overexpresses FMN1 gene coding for Riboflavin Kinase, accumulates significant amounts of flavin mononucleotide (FMN) in the cultural liquid. The effectiveness of FMN production by this strain under different conditions was evaluated. First, the medium composition was optimized in shake flask cultures. After preliminary experiments for nitrogen source selection, the two-level Plackett–Burman (PB) design was performed to screen medium components that significantly influence the FMN production. Among the 15 variables tested, KH2PO4, CaCl2, (NH4)6Mo7O24, CuSO4 and yeast extract, were identified as the most significant factors for FMN production (confidence levels above 95%). In order to investigate the quantitative effects for five variables selected from PB design on FMN production, a central composite design (CCD) was subsequently employed for further optimization. The optimization strategies used led to a 4.77-fold increase in the FMN production. A batch culture profile in a 1 L fermenter was consequently designed according to the optimal medium observed in shake flasks. A final FMN concentration of 231 ± 4.11 mg/L was obtained in 40 h, which further verified the practicability of the used strategy.
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production of flavin mononucleotide by metabolically engineered yeast candida famata
Metabolic Engineering, 2009Co-Authors: Valentyna Y Yatsyshyn, Olena P Ishchuk, Daria V Fedorovych, Andriy Y Voronovsky, Andriy A SibirnyAbstract:Abstract Recombinant strains of the flavinogenic yeast Candida famata able to overproduce flavin mononucleotide (FMN) that contain FMN1 gene encoding Riboflavin (RF) Kinase driven by the strong constitutive promoter TEF1 (translation elongation factor 1α) were constructed. Transformation of these strains with the additional plasmid containing the FMN1 gene under the TEF1 promoter resulted in the 200-fold increase in the Riboflavin Kinase activity and 100-fold increase in FMN production as compared to the wild-type strain (last feature was found only in iron-deficient medium). Overexpression of the FMN1 gene in the mutant that has deregulated Riboflavin biosynthesis pathway and high level of Riboflavin production in iron-sufficient medium led to the 30-fold increase in the Riboflavin Kinase activity and 400-fold increase in FMN production of the resulted transformants. The obtained C. famata recombinant strains can be used for the further construction of improved FMN overproducers.
Ana Serrano - One of the best experts on this subject based on the ideXlab platform.
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Insights into the FMNAT Active Site of FAD Synthase: Aromaticity is Essential for Flavin Binding and Catalysis.
International Journal of Molecular Sciences, 2020Co-Authors: Ana Serrano, Sonia Arilla-luna, M. MedinaAbstract:The last step in the biosynthesis of flavin adenine dinucleotide (FAD) is considered a target for the design of antimicrobial drugs because it is carried out by two non-homologous proteins in eukaryotic and prokaryotic organisms. Monofunctional FMN: adenylyltransferases (FMNAT) in Eukarya and FMNAT modules of bifunctional FAD synthases (FADS) in Prokarya belong to different structural families with dissimilar chemistry and binding modes for the substrates. In this study, we analyzed the relevance of the hydrophobic environment of the flavin isoalloxazine in the FMNAT active site of Corynebacterium ammoniagenes FADS (CaFADS) through the mutational analysis of its F62, Y106, and F128 residues. They form the isoalloxazine binding cavity and are highly conserved in the prokaryotic FADS family. The spectroscopic, steady-state kinetics and thermodynamic data presented indicate that distortion of aromaticity at the FMNAT isoalloxazine binding cavity prevents FMN and FAD from correct accommodation in their binding cavity and, as a consequence, decreases the efficiency of the FMNAT activity. Therefore, the side-chains of F62, Y106 and F128 are relevant in the formation of the catalytic competent complex during FMNAT catalysis in CaFADS. The introduced mutations also modulate the activity occurring at the Riboflavin Kinase (RFK) module of CaFADS, further evidencing the formation of quaternary assemblies during catalysis.
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Specific Features for the Competent Binding of Substrates at the FMN Adenylyltransferase Site of FAD Synthase from Corynebacterium ammoniagenes.
International Journal of Molecular Sciences, 2019Co-Authors: Sonia Arilla-luna, Ana Serrano, Milagros MedinaAbstract:Bifunctional FAD synthases (FADSs) catalyze FMN (flavin mononucleotide) and FAD (flavinadenine dinucleotide) biosynthesis at their C-Riboflavin Kinase (RFK) and N-FMN:adenylyltransferase (FMNAT) modules, respectively. Biophysical properties and requirements for their FMNAT activity differ among species. Here, we evaluate the relevance of the integrity of the binding site of the isoalloxazine of flavinic substrates for FMNAT catalysis in Corynebacterium ammoniagenes FADS (CaFADS). We have substituted P56 and P58, belonging to a conserved motif, as well as L98. These residues shape the isoalloxazine FMNAT site, although they are not expected to directly contact it. All substitutions override enzyme ability to transform substrates at the FMNAT site, although most variants are able to bind them. Spectroscopic properties and thermodynamic parameters for the binding of ligands indicate that mutations alter their interaction modes. Substitutions also modulate binding and kinetic properties at the RFK site, evidencing the crosstalk of different protomers within CaFADS assemblies during catalysis. In conclusion, despite the FMNAT site for the binding of substrates in CaFADS appearing as a wide open cavity, it is finely tuned to provide the competent binding conformation of substrates. In particular, P56, P58 and L98 shape the isoalloxazine site to place the FMN- and FAD-reacting phosphates in optimal geometry for catalysis.
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The Dimer-of-Trimers Assembly Prevents Catalysis at the Transferase Site of Prokaryotic FAD Synthase.
Biophysical Journal, 2018Co-Authors: Isaias Lans, Ana Serrano, Juan Seco, Ricardo Burbano, Pilar Cossio, Martha C. Daza, Milagros MedinaAbstract:Abstract Flavin mononucleotide (FMN) and flavin-adenine dinucleotide (FAD) are essential flavoprotein cofactors. A Riboflavin Kinase (RFK) activity catalyzes Riboflavin phosphorylation to FMN, which can then be transformed into FAD by an FMN:adenylyltransferase (FMNAT) activity. Two enzymes are responsible for each one of these activities in eukaryotes, whereas prokaryotes have a single bifunctional enzyme, FAD synthase (FADS). FADS folds in two independent modules: the C-terminal with RFK activity and the N-terminal with FMNAT activity. Differences in structure and chemistry for the FMNAT catalysis among prokaryotic and eukaryotic enzymes pointed to the FMNAT activity of prokaryotic FADS as a potential antimicrobial target, making the structural model of the bacterial FMNAT module in complex with substrates relevant to understand the FADS catalytic mechanism and to the discovery of antimicrobial drugs. However, such a crystallographic complex remains elusive. Here, we have used molecular docking and molecular dynamics simulations to generate energetically stable interactions of the FMNAT module of FADS from Corynebacterium ammoniagenes with ATP/Mg2+ and FMN in both the monomeric and dimer-of-trimers assemblies reported for this protein. For the monomer, we have identified the residues that accommodate the reactive phosphates in a conformation compatible with catalysis. Interestingly, for the dimer-of-trimers conformation, we have found that the RFK module negatively influences FMN binding at the interacting FMNAT module. These results agree with calorimetric data of purified samples containing nearly 100% monomer or nearly 100% dimer-of-trimers, indicating that FMN binds to the monomer but not to the dimer-of-trimers. Such observations support regulation of flavin homeostasis by quaternary C. ammoniagenes FADS assemblies.
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Kinetics and thermodynamics of the protein-ligand interactions in the Riboflavin Kinase activity of the FAD synthetase from Corynebacterium ammoniagenes
Scientific Reports, 2017Co-Authors: María Sebastián, Ana Serrano, Adrián Velázquez-campoy, Milagros MedinaAbstract:Enzymes known as bifunctional and bimodular prokaryotic type-I FAD synthetase (FADS) exhibit ATP:Riboflavin Kinase (RFK) and FMN:ATP adenylyltransferase (FMNAT) activities in their C-terminal and N-terminal modules, respectively, and produce flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD). These act as cofactors of a plethora of flavoproteins in all organisms. Therefore, regulation of their production maintains the cellular flavoproteome homeostasis. Here, we focus on regulation of the FMN synthesis in Corynebacterium ammoniagenes (Ca) by the inhibition of its RFK activity by substrates and products of the reaction. We use a truncated CaFADS variant consisting in the isolated C-terminal RFK module, whose RFK activity is similar to that of the full-length enzyme. Inhibition of the RFK activity by the RF substrate is independent of the FMNAT module, and FMN production, in addition to being inhibited by an excess of RF, is also inhibited by both of the reaction products. Pre-steady-state kinetic and thermodynamic studies reveal key aspects to the substrates induced fit to produce the catalytically competent complex. Among them, the role of Mg2+ in the concerted allocation of substrates for catalysis and the ensemble of non-competent complexes that contribute to the regulated inhibition of the RFK activity are particularly relevant.
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The trimer interface in the quaternary structure of the bifunctional prokaryotic FAD synthetase from Corynebacterium ammoniagenes.
Scientific Reports, 2017Co-Authors: Ana Serrano, Beatriz Herguedas, Marta Martínez-júlvez, Adrián Velázquez-campoy, María Sebastián, Sonia Arilla-luna, Silvia Baquedano, Milagros MedinaAbstract:Bifunctional FAD synthetases (FADSs) fold in two independent modules; The C-terminal Riboflavin Kinase (RFK) catalyzes the RFK activity, while the N-terminal FMN-adenylyltransferase (FMNAT) exhibits the FMNAT activity. The search for macromolecular interfaces in the Corynebacterium ammoniagenes FADS (CaFADS) crystal structure predicts a dimer of trimers organization. Within each trimer, a head-to-tail arrangement causes the RFK and FMNAT catalytic sites of the two neighboring protomers to approach, in agreement with active site residues of one module influencing the activity at the other. We analyze the relevance of the CaFADS head-to-tail macromolecular interfaces to stabilization of assemblies, catalysis and ligand binding. With this aim, we evaluate the effect of point mutations in loop L1c-FlapI, loop L6c, and helix α1c of the RFK module (positions K202, E203, F206, D298, V300, E301 and L304), regions at the macromolecular interface between two protomers within the trimer. Although none of the studied residues is critical in the formation and dissociation of assemblies, residues at L1c-FlapI and helix α1c particularly modulate quaternary architecture, as well as ligand binding and kinetic parameters involved with RFK and FMNAT activities. These data support the influence of transient oligomeric structures on substrate accommodation and catalysis at both CaFADS active sites.
Daria V Fedorovych - One of the best experts on this subject based on the ideXlab platform.
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medium optimization for production of flavin mononucleotide by the recombinant strain of the yeast candida famata using statistical designs
Biochemical Engineering Journal, 2010Co-Authors: Valentyna Y Yatsyshyn, Daria V Fedorovych, Andriy A SibirnyAbstract:Abstract The recombinant strain of the yeast Candida famata 13-76 that overexpresses FMN1 gene coding for Riboflavin Kinase, accumulates significant amounts of flavin mononucleotide (FMN) in the cultural liquid. The effectiveness of FMN production by this strain under different conditions was evaluated. First, the medium composition was optimized in shake flask cultures. After preliminary experiments for nitrogen source selection, the two-level Plackett–Burman (PB) design was performed to screen medium components that significantly influence the FMN production. Among the 15 variables tested, KH2PO4, CaCl2, (NH4)6Mo7O24, CuSO4 and yeast extract, were identified as the most significant factors for FMN production (confidence levels above 95%). In order to investigate the quantitative effects for five variables selected from PB design on FMN production, a central composite design (CCD) was subsequently employed for further optimization. The optimization strategies used led to a 4.77-fold increase in the FMN production. A batch culture profile in a 1 L fermenter was consequently designed according to the optimal medium observed in shake flasks. A final FMN concentration of 231 ± 4.11 mg/L was obtained in 40 h, which further verified the practicability of the used strategy.
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production of flavin mononucleotide by metabolically engineered yeast candida famata
Metabolic Engineering, 2009Co-Authors: Valentyna Y Yatsyshyn, Olena P Ishchuk, Daria V Fedorovych, Andriy Y Voronovsky, Andriy A SibirnyAbstract:Abstract Recombinant strains of the flavinogenic yeast Candida famata able to overproduce flavin mononucleotide (FMN) that contain FMN1 gene encoding Riboflavin (RF) Kinase driven by the strong constitutive promoter TEF1 (translation elongation factor 1α) were constructed. Transformation of these strains with the additional plasmid containing the FMN1 gene under the TEF1 promoter resulted in the 200-fold increase in the Riboflavin Kinase activity and 100-fold increase in FMN production as compared to the wild-type strain (last feature was found only in iron-deficient medium). Overexpression of the FMN1 gene in the mutant that has deregulated Riboflavin biosynthesis pathway and high level of Riboflavin production in iron-sufficient medium led to the 30-fold increase in the Riboflavin Kinase activity and 400-fold increase in FMN production of the resulted transformants. The obtained C. famata recombinant strains can be used for the further construction of improved FMN overproducers.
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Construction of the flavinogenic yeast Candida famata strains with high Riboflavin Kinase activity using gene engineering
Ukrains'kyi biokhimichnyi zhurnal (1999 ), 2006Co-Authors: Olena P Ishchuk, Iatsyshyn Viu, Kostyantyn V. Dmytruk, Voronovs'kyĭ Aia, Daria V FedorovychAbstract:Abstract The recombinant strains of the flavinogenic yeast Candida famata, which contain the DNA fragment consisting of the FMN1 gene (encoding the Riboflavin Kinase, enzyme that converts Riboflavin to flavinmononucleotide) driven by the strong promoters (the regulated RIB1 or constitutive TEF1 promoter) were isolated. Riboflavin Kinase activity in the isolated transformants was tested. The 6-8-fold increase of the Riboflavin Kinase activity was shown in the recombinant strains containing the integrated Debaryomyces hansenii FMN1 gene under the strong constitutive TEF1 promoter. The recombinant strains can be used for the following construction of flavinmononucleotide overproducers.
Valentyna Y Yatsyshyn - One of the best experts on this subject based on the ideXlab platform.
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medium optimization for production of flavin mononucleotide by the recombinant strain of the yeast candida famata using statistical designs
Biochemical Engineering Journal, 2010Co-Authors: Valentyna Y Yatsyshyn, Daria V Fedorovych, Andriy A SibirnyAbstract:Abstract The recombinant strain of the yeast Candida famata 13-76 that overexpresses FMN1 gene coding for Riboflavin Kinase, accumulates significant amounts of flavin mononucleotide (FMN) in the cultural liquid. The effectiveness of FMN production by this strain under different conditions was evaluated. First, the medium composition was optimized in shake flask cultures. After preliminary experiments for nitrogen source selection, the two-level Plackett–Burman (PB) design was performed to screen medium components that significantly influence the FMN production. Among the 15 variables tested, KH2PO4, CaCl2, (NH4)6Mo7O24, CuSO4 and yeast extract, were identified as the most significant factors for FMN production (confidence levels above 95%). In order to investigate the quantitative effects for five variables selected from PB design on FMN production, a central composite design (CCD) was subsequently employed for further optimization. The optimization strategies used led to a 4.77-fold increase in the FMN production. A batch culture profile in a 1 L fermenter was consequently designed according to the optimal medium observed in shake flasks. A final FMN concentration of 231 ± 4.11 mg/L was obtained in 40 h, which further verified the practicability of the used strategy.
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production of flavin mononucleotide by metabolically engineered yeast candida famata
Metabolic Engineering, 2009Co-Authors: Valentyna Y Yatsyshyn, Olena P Ishchuk, Daria V Fedorovych, Andriy Y Voronovsky, Andriy A SibirnyAbstract:Abstract Recombinant strains of the flavinogenic yeast Candida famata able to overproduce flavin mononucleotide (FMN) that contain FMN1 gene encoding Riboflavin (RF) Kinase driven by the strong constitutive promoter TEF1 (translation elongation factor 1α) were constructed. Transformation of these strains with the additional plasmid containing the FMN1 gene under the TEF1 promoter resulted in the 200-fold increase in the Riboflavin Kinase activity and 100-fold increase in FMN production as compared to the wild-type strain (last feature was found only in iron-deficient medium). Overexpression of the FMN1 gene in the mutant that has deregulated Riboflavin biosynthesis pathway and high level of Riboflavin production in iron-sufficient medium led to the 30-fold increase in the Riboflavin Kinase activity and 400-fold increase in FMN production of the resulted transformants. The obtained C. famata recombinant strains can be used for the further construction of improved FMN overproducers.