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Nechaev AA, Gonzalez G, Verma P, Peshkov VA, Bannykh A, Hashemi A, Hannonen J, Hamza A, Papai I, Laasonen K, Peljo P, Pihko PM. Exploration of Vitamin B6-Based Redox-Active Pyridinium Salts towards the Application in Aqueous Organic Flow Batteries. Chemistry 2024:e202400828. [PMID: 38640462 DOI: 10.1002/chem.202400828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 04/15/2024] [Accepted: 04/16/2024] [Indexed: 04/21/2024]
Abstract
Pyridoxal hydrochloride, a vitamin B6 vitamer, was synthetically converted to a series of diverse redox-active benzoyl pyridinium salts. Cyclic voltammetry studies demonstrated redox reversibility under basic conditions, and two of the most promising salts were subjected to laboratory-scale redox flow battery tests involving galvanostatic cycling at 10 mM in 0.1 M NaOH. In these tests, the battery was charged completely, corresponding to the transfer of two electrons to the electrolyte, but no discharge was observed. Both CV analysis and electrochemical simulations confirmed that the redox wave observed in the experimental voltammograms corresponds to a two-electron process. To explain the irreversibility in the battery tests, we conducted bulk electrolysis with the benzoyl pyridinium salts, affording the corresponding benzylic secondary alcohols. Computational studies suggest that the reduction proceeds in three consecutive steps: first electron transfer (ET), then proton-coupled electron transfer (PCET) and finally proton transfer (PT) to give the secondary alcohol. 1H NMR deuterium exchange studies indicated that the last PT step is not reversible in 0.1 M NaOH, rendering the entire redox process irreversible. The apparent reversibility observed in CV at the basic media likely arises from the slow rate of the PT step at the timescale of the measurement.
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Affiliation(s)
- Anton A Nechaev
- University of Jyväskylä, Department of Chemistry, 40014, Jyväskylä, FINLAND
| | - Gabriel Gonzalez
- University of Turku, Department of Mechanical and Materials Engineering, 20014, Turku, FINLAND
| | - Prachi Verma
- University of Jyväskylä, Department of Chemistry, 40014, Jyväskylä, FINLAND
| | - Vsevolod A Peshkov
- University of Jyväskylä, Department of Chemistry, 40014, Jyväskylä, FINLAND
| | - Anton Bannykh
- University of Jyväskylä, Department of Chemistry, 40014, Jyväskylä, FINLAND
| | - Arsalan Hashemi
- Aalto University, Department of Chemistry and Material Science, 02150, Espoo, FINLAND
| | - Jenna Hannonen
- University of Turku, Department of Mechanical and Materials Engineering, 20014, Turku, FINLAND
| | - Andrea Hamza
- MTA Research Centre for Natural Sciences, Institute of Organic Chemistry, 1117, Budapest, HUNGARY
| | - Imre Papai
- MTA Research Centre for Natural Sciences, Institute of Organic Chemistry, 1117, Budapest, HUNGARY
| | - Kari Laasonen
- Aalto University, Department of Chemistry and Material Science, 02150, Espoo, FINLAND
| | - Pekka Peljo
- University of Turku, Department of Mechanical and Materials Engineering, 20014, Turku, FINLAND
| | - Petri M Pihko
- University of Jyvaskyla, Department of Chemistry, Survontie 9, P.O.B. 35, FIN-40014 JYU, Jyväskylä, FINLAND
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Gatto CC, Dias LM, Paiva CA, da Silva ICR, Freire DO, Tormena RPI, Nascimento ÉCM, Martins JBL. Effects of changing ions on the crystal design, non-covalent interactions, antimicrobial activity, and molecular docking of Cu(II) complexes with a pyridoxal-hydrazone ligand. Front Chem 2024; 12:1347370. [PMID: 38361747 PMCID: PMC10867249 DOI: 10.3389/fchem.2024.1347370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 01/05/2024] [Indexed: 02/17/2024] Open
Abstract
The present work reports the influence of the presence of different ions (Cl-, Br-, NO3 -, or SO4 2-) on the formation and proprieties of Cu(II) complexes with pyridoxal-benzoylhydrazone (PLBHZ). Four new complexes were successfully synthesized, [CuCl2(PLBHZ)] (1), [CuBr2(PLBHZ)] (2), [CuCl(PLBHZ)H2O]⋅NO3⋅H2O (3), and [CuSO4(PLBHZ)H2O]⋅3H2O (4), and characterized by spectroscopic and physicochemical methods. A single-crystal X-ray study reveals the Schiff base coordinated to the metal center tridentate by the ONS-donor system, resulting in distorted square pyramidal coordination geometries. Noncovalent interactions were investigated by 3D Hirshfeld surface analysis by the d norm function, 2D fingerprint plots, and full interaction maps. The ion exchange is important in forming three-dimensional networks with π⋅⋅⋅π stacking interactions and intermolecular hydrogen bonds. The in vitro biological activity of the free ligand and metal complexes was evaluated against Gram-positive and Gram-negative bacterial strains and the free pyridoxal-hydrazone ligand showed higher activity than their Cu(II) complexes. Molecular docking was used to predict the inhibitory activity of the ligand and complexes against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli bacteria.
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Affiliation(s)
- Claudia C. Gatto
- Laboratory of Inorganic Synthesis and Crystallography, Institute of Chemistry, University of Brasilia, Brasília-DF, Brazil
| | - Lucas M. Dias
- Laboratory of Inorganic Synthesis and Crystallography, Institute of Chemistry, University of Brasilia, Brasília-DF, Brazil
| | - Clarisse A. Paiva
- Laboratory of Inorganic Synthesis and Crystallography, Institute of Chemistry, University of Brasilia, Brasília-DF, Brazil
| | - Izabel C. R. da Silva
- Graduate Program in Health Sciences and Technologies, Faculty UnB Ceilândia, University of Brasilia, Brasília-DF, Brazil
| | - Daniel O. Freire
- Graduate Program in Health Sciences and Technologies, Faculty UnB Ceilândia, University of Brasilia, Brasília-DF, Brazil
| | - Renata P. I. Tormena
- Graduate Program in Health Sciences and Technologies, Faculty UnB Ceilândia, University of Brasilia, Brasília-DF, Brazil
| | - Érica C. M. Nascimento
- Laboratory of Computational Chemistry, Institute of Chemistry, University of Brasilia, Brasília-DF, Brazil
| | - João B. L. Martins
- Laboratory of Computational Chemistry, Institute of Chemistry, University of Brasilia, Brasília-DF, Brazil
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Harrison SA, Webb WL, Rammu H, Lane N. Prebiotic Synthesis of Aspartate Using Life's Metabolism as a Guide. Life (Basel) 2023; 13:life13051177. [PMID: 37240822 DOI: 10.3390/life13051177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 04/29/2023] [Accepted: 05/10/2023] [Indexed: 05/28/2023] Open
Abstract
A protometabolic approach to the origins of life assumes that the conserved biochemistry of metabolism has direct continuity with prebiotic chemistry. One of the most important amino acids in modern biology is aspartic acid, serving as a nodal metabolite for the synthesis of many other essential biomolecules. Aspartate's prebiotic synthesis is complicated by the instability of its precursor, oxaloacetate. In this paper, we show that the use of the biologically relevant cofactor pyridoxamine, supported by metal ion catalysis, is sufficiently fast to offset oxaloacetate's degradation. Cu2+-catalysed transamination of oxaloacetate by pyridoxamine achieves around a 5% yield within 1 h, and can operate across a broad range of pH, temperature, and pressure. In addition, the synthesis of the downstream product β-alanine may also take place in the same reaction system at very low yields, directly mimicking an archaeal synthesis route. Amino group transfer supported by pyridoxal is shown to take place from aspartate to alanine, but the reverse reaction (alanine to aspartate) shows a poor yield. Overall, our results show that the nodal metabolite aspartate and related amino acids can indeed be synthesised via protometabolic pathways that foreshadow modern metabolism in the presence of the simple cofactor pyridoxamine and metal ions.
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Affiliation(s)
- Stuart A Harrison
- Centre for Life's Origins and Evolution (CLOE), Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, UK
| | - William L Webb
- Centre for Life's Origins and Evolution (CLOE), Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, UK
| | - Hanadi Rammu
- Centre for Life's Origins and Evolution (CLOE), Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, UK
| | - Nick Lane
- Centre for Life's Origins and Evolution (CLOE), Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, UK
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Turck D, Bohn T, Castenmiller J, de Henauw S, Hirsch‐Ernst K, Knutsen HK, Maciuk A, Mangelsdorf I, McArdle HJ, Pelaez C, Pentieva K, Siani A, Thies F, Tsabouri S, Vinceti M, Fairweather‐Tait S, Vrolijk M, Fabiani L, Titz A, Naska A. Scientific opinion on the tolerable upper intake level for vitamin B6. EFSA J 2023; 21:e08006. [PMID: 37207271 PMCID: PMC10189633 DOI: 10.2903/j.efsa.2023.8006] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/21/2023] Open
Abstract
Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver a scientific opinion on the tolerable upper intake level (UL) for vitamin B6. Systematic reviews of the literature were conducted by a contractor. The relationship between excess vitamin B6 intakes and the development of peripheral neuropathy is well established and is the critical effect on which the UL is based. A lowest-observed-effect-level (LOAEL) could not be established based on human data. A reference point (RP) of 50 mg/day is identified by the Panel from a case-control study, supported by data from case reports and vigilance data. An uncertainty factor (UF) of 4 is applied to the RP to account for the inverse relationship between dose and time to onset of symptoms and the limited data available. The latter covers uncertainties as to the level of intake that would represent a LOAEL. This leads to a UL of 12.5 mg/day. From a subchronic study in Beagle dogs, a LOAEL of 50 mg/kg body weight (bw) per day can be identified. Using an UF of 300, and a default bw of 70 kg, a UL of 11.7 mg/day can be calculated. From the midpoint of the range of these two ULs and rounding down, a UL of 12 mg/day is established by the Panel for vitamin B6 for adults (including pregnant and lactating women). ULs for infants and children are derived from the UL for adults using allometric scaling: 2.2-2.5 mg/day (4-11 months), 3.2-4.5 mg/day (1-6 years), 6.1-10.7 mg/day (7-17 years). Based on available intake data, EU populations are unlikely to exceed ULs, except for regular users of food supplements containing high doses of vitamin B6.
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Yang RJ, Wang N, Ma X, Gong MD, Wang YR, Meng SY, Liu ZY, Tang Q. A Novel Two-Dimensional Liquid Chromatography Combined with Ultraviolet Detection Method for Quantitative Determination of Pyridoxal 5'-Phosphate, 4-Pyridoxine Acid and Pyridoxal in Animal Plasma. Animals (Basel) 2023; 13:ani13081333. [PMID: 37106896 PMCID: PMC10135266 DOI: 10.3390/ani13081333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 03/17/2023] [Accepted: 04/11/2023] [Indexed: 04/29/2023] Open
Abstract
Vitamin B6 is an indispensable micronutrient in organisms and is widely distributed in blood, tissues, and organs. Changes in the content and ratio of vitamin B6 can affect the entire physiological condition of the body, so it becomes particularly important to reveal the relationship between changes in its content and disease by monitoring vitamin B6 levels in the organism. In this study, a two-dimensional liquid chromatography-UV detector (2D-LC-UV) was used to establish a method for the simultaneous detection of PLP, PA, and PL for the first time. First, PLP, PA, and PL were extracted with plasma: 0.6 M TCA: ultrapure water = 1:2:3 (v/v/v) and then derivatized. Enrichment and preliminary separation were performed on a one-dimensional column and automatically entered into a two-dimensional column for further separation. This method exhibited good selectivity, and the correlation coefficients for the analyte calibration curves were >0.99. The detection limits for PLP, PA, and PL were 0.1, 0.2, and 4 nmol/L, respectively. The results showed that the system has high loading capacity, excellent resolution, and a good peak shape. This method is expected to provide applicability for the determination of PLP, PA, and PL in pharmacological, pharmaceutical, and clinical research.
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Affiliation(s)
- Rong-Ju Yang
- College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China
- Hunan Engineering Technology Research Center of Veterinary Drugs, Hunan Agricultural University, Changsha 410128, China
| | - Na Wang
- College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China
- Hunan Engineering Technology Research Center of Veterinary Drugs, Hunan Agricultural University, Changsha 410128, China
| | - Xiao Ma
- College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China
- Hunan Engineering Technology Research Center of Veterinary Drugs, Hunan Agricultural University, Changsha 410128, China
| | - Meng-Die Gong
- College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China
- Hunan Engineering Technology Research Center of Veterinary Drugs, Hunan Agricultural University, Changsha 410128, China
| | - Yi-Rong Wang
- College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China
- Hunan Engineering Technology Research Center of Veterinary Drugs, Hunan Agricultural University, Changsha 410128, China
| | - Si-Yu Meng
- College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China
- Hunan Engineering Technology Research Center of Veterinary Drugs, Hunan Agricultural University, Changsha 410128, China
| | - Zhao-Ying Liu
- College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China
- Hunan Engineering Technology Research Center of Veterinary Drugs, Hunan Agricultural University, Changsha 410128, China
| | - Qi Tang
- College of Horticulture, Hunan Agricultural University, Changsha 410128, China
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Debele TA, Chen CK, Yu LY, Lo CL. Lipopolyplex-Mediated Co-Delivery of Doxorubicin and FAK siRNA to Enhance Therapeutic Efficiency of Treating Colorectal Cancer. Pharmaceutics 2023; 15:pharmaceutics15020596. [PMID: 36839918 PMCID: PMC9968081 DOI: 10.3390/pharmaceutics15020596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 02/03/2023] [Accepted: 02/08/2023] [Indexed: 02/12/2023] Open
Abstract
Tumor metastasis is a major concern in cancer therapy. In this context, focal adhesion kinase (FAK) gene overexpression, which mediates cancer cell migration and invasion, has been reported in several human tumors and is considered a potential therapeutic target. However, gene-based treatment has certain limitations, including a lack of stability and low transfection ability. In this study, a biocompatible lipopolyplex was synthesized to overcome the aforementioned limitations. First, polyplexes were prepared using poly(2-Hydroxypropyl methacrylamide-co-methylacrylate-hydrazone-pyridoxal) (P(HPMA-co-MA-hyd-VB6)) copolymers, which bore positive charges at low pH value owing to protonation of pyridoxal groups and facilitated electrostatic interactions with negatively charged FAK siRNA. These polyplexes were then encapsulated into methoxy polyethylene glycol (mPEG)-modified liposomes to form lipopolyplexes. Doxorubicin (DOX) was also loaded into lipopolyplexes for combination therapy with siRNA. Experimental results revealed that lipopolyplexes successfully released DOX at low pH to kill cancer cells and induced siRNA out of endosomes to inhibit the translation of FAK proteins. Furthermore, the efficient accumulation of lipopolyplexes in the tumors led to excellent cancer therapeutic efficacy. Overall, the synthesized lipopolyplex is a suitable nanocarrier for the co-delivery of chemotherapeutic agents and genes to treat cancers.
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Affiliation(s)
- Tilahun Ayane Debele
- Department of Biomedical Engineering, National Yang Ming Chiao Tung University, Taipei 112, Taiwan
- Department of Chemical & Environmental Engineering, College of Engineering and Applied Science (CEAS), University of Cincinnati, Cincinnati, OH 452, USA
| | - Chi-Kang Chen
- Department of Biomedical Engineering, National Yang Ming Chiao Tung University, Taipei 112, Taiwan
| | - Lu-Yi Yu
- Department of Biomedical Engineering, National Yang Ming Chiao Tung University, Taipei 112, Taiwan
- Correspondence: (L.-Y.Y.); (C.-L.L.); Tel.: +886-2-28267000 (ext. 67914) (C.-L.L.)
| | - Chun-Liang Lo
- Department of Biomedical Engineering, National Yang Ming Chiao Tung University, Taipei 112, Taiwan
- Medical Device Innovation and Translation Center, National Yang Ming Chiao Tung University, Taipei 112, Taiwan
- Correspondence: (L.-Y.Y.); (C.-L.L.); Tel.: +886-2-28267000 (ext. 67914) (C.-L.L.)
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Denise R, Babor J, Gerlt JA, de Crécy-Lagard V. Pyridoxal 5'-phosphate synthesis and salvage in Bacteria and Archaea: predicting pathway variant distributions and holes. Microb Genom 2023; 9:mgen000926. [PMID: 36729913 PMCID: PMC9997740 DOI: 10.1099/mgen.0.000926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Pyridoxal 5’-phosphate or PLP is a cofactor derived from B6 vitamers and essential for growth in all known organisms. PLP synthesis and salvage pathways are well characterized in a few model species even though key components, such as the vitamin B6 transporters, are still to be identified in many organisms including the model bacteria Escherichia coli or Bacillus subtilis. Using a comparative genomic approach, PLP synthesis and salvage pathways were predicted in 5840 bacterial and archaeal species with complete genomes. The distribution of the two known de novo biosynthesis pathways and previously identified cases of non-orthologous displacements were surveyed in the process. This analysis revealed that several PLP de novo pathway genes remain to be identified in many organisms, either because sequence similarity alone cannot be used to discriminate among several homologous candidates or due to non-orthologous displacements. Candidates for some of these pathway holes were identified using published TnSeq data, but many remain. We find that ~10 % of the analysed organisms rely on salvage but further analyses will be required to identify potential transporters. This work is a starting point to model the exchanges of B6 vitamers in communities, predict the sensitivity of a given organism to drugs targeting PLP synthesis enzymes, and identify numerous gaps in knowledge that will need to be tackled in the years to come.
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Affiliation(s)
- Rémi Denise
- Department of Microbiology and Cell Sciences, Gainesville, USA.,Present address: APC Microbiome Ireland, University College Cork, Cork, Ireland
| | - Jill Babor
- Department of Microbiology and Cell Sciences, Gainesville, USA
| | | | - Valérie de Crécy-Lagard
- Department of Microbiology and Cell Sciences, Gainesville, USA.,Genetics Institute, University of Florida, Gainesville, FL 32611, USA
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8
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Scaccaglia M, Rega M, Vescovi M, Pinelli S, Tegoni M, Bacci C, Pelosi G, Bisceglie F. Gallium(III)- Pyridoxal Thiosemicarbazone Derivatives as Nontoxic Agents against Gram Negative Bacteria. Metallomics 2022; 14:6694003. [PMID: 36073748 DOI: 10.1093/mtomcs/mfac070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 08/18/2022] [Indexed: 11/14/2022]
Abstract
Many bacterial strains are developing mechanism of resistance to antibiotics, rendering last-resort antibiotics inactive. Therefore, new drugs are needed and in particular metal-based compounds represent a valid starting point to explore new antibiotic classes. In this study we have chosen to investigate gallium(III) complexes for their potential antimicrobial activity against different strains of Klebsiella pneumoniae, Escherichia coli and Pseudomonas aeruginosa which have developed different type of resistance mechanism, including the expression of β-lactamases (NDM-1, ESβL or AmpC) or the production of biofilm. We studied a series of thiosemicarbabazones derived from pyridoxal, their related Ga(III) complexes, and the speciation in solution of the Ga(III)/ligand systems as a function of the pH. Proton dissociation constants and conditional stability constants of Ga(III) complexes were evaluated by UV/Vis spectroscopy, and the most relevant species at physiological pH were identified. The compounds are active against resistant Gram negative strain with minimal inhibitory concentration in the μM range, while no cytotoxicity was detected in eukaryotic cells.
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Affiliation(s)
- Mirco Scaccaglia
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124 Parma, Italy
| | - Martina Rega
- Department of Veterinary Science, University of Parma, Strada del Taglio 10, 43126 Parma, Italy
| | - Marianna Vescovi
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124 Parma, Italy
| | - Silvana Pinelli
- Department of Medicine and Surgery, University of Parma, Via Gramsci 14, 43126 Parma, Italy
| | - Matteo Tegoni
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124 Parma, Italy
| | - Cristina Bacci
- Department of Veterinary Science, University of Parma, Strada del Taglio 10, 43126 Parma, Italy
| | - Giorgio Pelosi
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124 Parma, Italy.,CERT, Center of Excellence for Toxicological Research, University of Parma, 43124 Parma, Italy
| | - Franco Bisceglie
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124 Parma, Italy.,CERT, Center of Excellence for Toxicological Research, University of Parma, 43124 Parma, Italy
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9
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Kavitha R, Reddy CVR, Sireesha B. Synthesis, spectroscopic and biological activity evaluation of Ni(II), Cu(II) and Zn(II) complexes of schiff base derived from pyridoxal and 4-fluorobenzohydrazide. Nucleosides Nucleotides Nucleic Acids 2021; 40:845-866. [PMID: 34379029 DOI: 10.1080/15257770.2021.1961271] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
A novel Schiff base ligand, 4-fluoro-N-((3-hydroxy-5-(hydroxymethyl)-2-methylpyridin-4-yl)methylene)benzohydrazide (PLFBH) was synthesized by condensationof pyridoxal and 4-fluorobenzohydrazide. Its complexes with Ni(II), Cu(II), and Zn(II) metal ionswere prepared and characterized by spectroscopic IR, 1H-NMR, UV, LC-MS, ESR, and powder XRD studies and by elemental analysis and thermal analysis, molar conductance, and magnetic susceptibility measurements. The results indicate the geometry of the complexes to be hexa coordinate distorted octahedral. Based on the electronic absorption and fluorescence emission spectra and viscosity studies, an intercalative mode of binding of the complexes with CT-DNA was suggested, which was also supported by DNA docking studies. The docking studies of metal complexes with DNA were carried out using Autodock 4.2. The in vitro anticancer assay for the Cu(II)-PLFBH complex was performed to assess the ability of the complex to inhibit human cell proliferation on HeLa human cervical carcinoma cells, MCF-7 human breast carcinoma cells, and A549 human lung carcinoma cells. The Cu(II)-PLFBH complex exhibited moderate to good inhibitory effect on the cancer cell lines studied. The complexes showed good cleavageability toward plasmid pBR322 DNA. The metal complexes were found to show good antibacterial activity against gram positive bacteria, Staphylococcus aureus and Bacillus cereus and gram negative bacteria Escherichia coli and Pseudomonas aeruginosa cultures,while the ligand showed marginal activity.Supplemental data for this article is available online at https://doi.org/10.1080/15257770.2021.1961271 .
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Affiliation(s)
- R Kavitha
- Department of Chemistry, Nizam College, Osmania University, Hyderabad, Telangana, India
| | - Ch Venkata Ramana Reddy
- Department of Chemistry, Jawaharlal Nehru Technological University Hyderabad, Hyderabad, Telangana, India
| | - B Sireesha
- Department of Chemistry, Nizam College, Osmania University, Hyderabad, Telangana, India
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10
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Johnston EA, Lloyd SB, Granger DL. Properties of a fungicidal product formed from a reaction between L-cystine and pyridoxal. Med Mycol 2021; 58:919-927. [PMID: 31915818 DOI: 10.1093/mmy/myz130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 12/06/2019] [Accepted: 12/12/2019] [Indexed: 11/14/2022] Open
Abstract
Previously we found that three components of a commonly used mammalian cell culture medium incorporated into agar killed cryptococci (Granger and Call 2019). The components were L-cystine, iron [Fe(III)], and pyridoxal (CIP). We now report on a buffered solution at neutral pH of the three components, which was highly fungicidal without agar. We showed that CIP fungicidal activity, identical to the findings with cell culture medium, was inactivated by visible light and was unstable with storage in the dark. Congeners replacing either pyridoxal or L-cystine in CIP revealed structural requirements for fungicidal activity. Replacing pyridoxal in CIP with 2-hydroxy-5-nitrobenzaldehyde produced a solution that was equally fungicidal and maintained fungicidal activity upon storage in the dark for up to 50 days. We employed methods for excluding iron from CIP and found that fungicidal activity was not affected. Upon mixing L-cystine and pyridoxal in buffer at pH 7.0, diode array spectroscopy revealed a red-shift of absorbance maximum from 391 nm to 398 nm. Our findings point to Schiff base reaction between the pyridoxal aldehyde group of C1 with the alpha amino group(s) of cystine to yield a fungicidal compound. Light at wave length approximately 400 nm inactivates this complex accompanied by bleaching of the pyridine ring of pyridoxal. Our findings may be useful for design of a class of fungicidal compounds formed through Schiff base reaction of disulfide compounds with aromatic ring-bearing aldehydes.
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Affiliation(s)
- Elizabeth A Johnston
- Division of Infectious Diseases, Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - Spencer B Lloyd
- Division of Infectious Diseases, Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - Donald L Granger
- Division of Infectious Diseases, Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, Utah, USA
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11
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Mayengbam S, Chleilat F, Reimer RA. Dietary Vitamin B6 Deficiency Impairs Gut Microbiota and Host and Microbial Metabolites in Rats. Biomedicines 2020; 8:biomedicines8110469. [PMID: 33147768 PMCID: PMC7693528 DOI: 10.3390/biomedicines8110469] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 10/28/2020] [Accepted: 10/30/2020] [Indexed: 12/15/2022] Open
Abstract
Vitamin B6 plays a crucial role as a cofactor in various enzymatic reactions but bacteria-produced vitamin B6 is not sufficient to meet host requirements. Our objective was to assess the impact of diet-derived vitamin B6 on gut microbiota and host serum metabolomics. Sprague–Dawley rats (n = 47) were fed a control, low B6 (LB6) or high B6 (HB6) diet for six weeks. Serum and cecal samples were collected for biochemical, metabolomics and gut microbiota profiling. There was a significant sex effect for gut microbiota and several metabolic markers. Bodyweight and percent body fat were significantly reduced in LB6 compared to control and HB6 rats. Microbial beta-diversity differed significantly between LB6 and the control and HB6 rats in both sexes. Lachnospiraceae_NK4A136_group and Bacteroides were the primary taxa driving the difference between LB6 and control. There was a significant separation of cecal and serum metabolites of LB6 compared to control and HB6 rats. In the cecum, arginine biosynthesis was impaired, while vitamin B6 metabolism, lysine degradation and nicotinate and nicotinamide metabolism were impaired in serum metabolite profiles. Cecal propionate and butyrate were significantly reduced in LB6 rats irrespective of sex. Host vitamin B6 deficiency but not excess significantly alters gut microbial composition and its metabolites.
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Affiliation(s)
- Shyamchand Mayengbam
- Department of Biochemistry, Memorial University of Newfoundland, St. John’s, NL A1C 5S7, Canada;
| | - Faye Chleilat
- Faculty of Kinesiology, University of Calgary, Calgary, AB T2N 1N4, Canada;
| | - Raylene A. Reimer
- Faculty of Kinesiology, University of Calgary, Calgary, AB T2N 1N4, Canada;
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada
- Correspondence:
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Tomioka Y, Kinoshita M, Umehara H, Nakayama T, Watanabe SY, Nakataki M, Numata S, Ohmori T. Association between serum folate levels and schizophrenia based on sex. Psychiatry Clin Neurosci 2020; 74:466-471. [PMID: 32445495 DOI: 10.1111/pcn.13074] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 04/17/2020] [Accepted: 05/10/2020] [Indexed: 02/06/2023]
Abstract
AIM Sex differences in serum folate concentrations are well known, but no studies have investigated the association between serum folate levels and schizophrenia based on sex. With this study in a Japanese population, we examined the difference in serum folate levels between patients with schizophrenia and non-psychiatric controls stratified by sex. The relations among serum folate levels, plasma total homocysteine (tHcy), and serum vitamin B6 (pyridoxal) levels were also examined using data from our previous studies. METHODS The serum folate concentrations of 482 patients diagnosed with schizophrenia and 1350 non-psychiatric control subjects were measured. We conducted an analysis of covariance to examine the differences in serum folate levels between the two groups based on sex. Spearman's rank correlation was used to evaluate the relations among folate, tHcy, and vitamin B6 levels. RESULTS In the control group, serum folate concentrations were higher in women than in men. Lower levels of serum folate were observed in both male and female patients with schizophrenia. An inverse correlation between serum folate and plasma tHcy and a weak positive correlation between serum folate and vitamin B6 were observed in the combined cohort. CONCLUSION Our findings suggest that: (i) a low serum folate level may be associated with schizophrenia regardless of sex; and (ii) folate administration may be beneficial for the treatment of schizophrenia. In schizophrenic patients with low serum folate levels, folate administration might result in improvements in high tHcy and an increase in low vitamin B6 levels.
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Affiliation(s)
- Yukiko Tomioka
- Department of Psychiatry, Institute of Biomedical Science, Tokushima University Graduate School, Tokushima, Japan
| | - Makoto Kinoshita
- Department of Psychiatry, Institute of Biomedical Science, Tokushima University Graduate School, Tokushima, Japan
| | - Hidehiro Umehara
- Department of Psychiatry, Institute of Biomedical Science, Tokushima University Graduate School, Tokushima, Japan
| | - Tomohiko Nakayama
- Department of Psychiatry, Institute of Biomedical Science, Tokushima University Graduate School, Tokushima, Japan
| | - Shin-Ya Watanabe
- Department of Psychiatry, Institute of Biomedical Science, Tokushima University Graduate School, Tokushima, Japan
| | - Masahito Nakataki
- Department of Psychiatry, Institute of Biomedical Science, Tokushima University Graduate School, Tokushima, Japan
| | - Shusuke Numata
- Department of Psychiatry, Institute of Biomedical Science, Tokushima University Graduate School, Tokushima, Japan
| | - Tetsuro Ohmori
- Department of Psychiatry, Institute of Biomedical Science, Tokushima University Graduate School, Tokushima, Japan
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Shikano H, Miyama Y, Ikeda R, Takeshi H, Suda J, Yoshinaga K, Taira S. Localization Analysis of Multiple Vitamins in Dried Persimmon (Diospyros kaki) Using Matrix-assisted Laser Desorption/ionization Mass Spectrometry Imaging. J Oleo Sci 2020; 69:959-964. [PMID: 32641617 DOI: 10.5650/jos.ess20143] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The drying process used for persimmon fruit (Diospyros kaki) can alter the composition of nutrients, and especially vitamins. We visually determined whether the amounts of vitamin A1, vitamin B6 and vitamin C vary after drying persimmon fruit, using matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) imaging. Drying altered the amount of moisture between the fruit interior and surface. Vitamin A1 is lipophilic and localized at the desiccated outer regions (pericarp) and not in the inner region (mesocarp and endocarp), and its concentration was increased 3.4 times in dried fruit compared with raw persimmon. Vitamin B1 and B6 are water-soluble and concentrated in the moist mesocarp. The vitamin C content of dried persimmon is decreased by drying in the sun. The drying process affected the localizations and amounts of all the vitamins. The observed opposite localization of vitamin A1 compared to B1 and B6 was due to vitamin A1 being lipophilic and B1 and B6 being water soluble. Multiplevitamin imaging using MALDI-MSI has great potential for enhancing commodity value and for visually investigating the effects of manufacturing processes.
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Affiliation(s)
- Hitomi Shikano
- Faculty of Food and Agricultural Sciences, Fukushima University
| | - Yoko Miyama
- Faculty of Food and Agricultural Sciences, Fukushima University
| | - Ryuzoh Ikeda
- Faculty of Food and Agricultural Sciences, Fukushima University
| | | | | | | | - Shu Taira
- Faculty of Food and Agricultural Sciences, Fukushima University
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Sasaki Y, Tsuchido Y, Yoshimura T, Akiyoshi K. Nanogelation and Thermal Stabilization of Enzyme by Vitamin B 6-Bearing Polysaccharide as Biocrosslinker. ACS Biomater Sci Eng 2019; 5:5752-5758. [PMID: 33405708 DOI: 10.1021/acsbiomaterials.9b00026] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Nanogels containing a protein (carbonic anhydrase, CA) were prepared by cross-linking CA and pyridoxal (vitamin B6)-bearing pullulan (PLPP) as a biocrosslinker via Schiff base formation. UV titration and high-performance liquid chromatography confirmed that CA was quantitatively complexed with PLPP in the presence of zinc ions. Dynamic light scattering and transmission electron microscopy showed that the nanogel diameter was about 20 nm. CA retained 90% of its native activity after complexation with PLPP. Moreover, the residual enzymatic activity of CA after heating and its long-term storage stability at room temperature were improved by complexation with PLPP. Enzyme nanogelation with PLPP is an efficient method for enzyme stabilization.
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Affiliation(s)
- Yoshihiro Sasaki
- Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 606-8501, Japan
| | - Yuji Tsuchido
- Department of Materials and Life Sciences, Faculty of Science and Technology, Sophia University, 7-1 Kioicho, Chiyoda, Tokyo 102-8554, Japan
| | - Takahiro Yoshimura
- Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 606-8501, Japan
| | - Kazunari Akiyoshi
- Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 606-8501, Japan.,The Exploratory Research for Advanced Technology (ERATO), Japan Science and Technology Agency (JST), K's Goban-cho bldg., 7 Goban-cho, chiyoda-ku, Tokyo 102-0076, Japan
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Tabatabayi ZS, Homayouni-Tabrizi M, Neamati A, Beyramabadi SA. Mn(II) complex of a vitamin B6 Schiff base as an exclusive apoptosis inducer in human MCF7 and HepG2 cancer cells: Synthesis, characterization, and biological studies. J Cell Biochem 2019; 121:2677-2689. [PMID: 31680295 DOI: 10.1002/jcb.29488] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 10/08/2019] [Indexed: 12/31/2022]
Abstract
Herein, a Mn(II) complex of the N,N'-dipyridoxyl(1,4-butanediamine) (═H2 L) Schiff base has been newly synthesized. The synthesized complex was characterized by several experimental methods. In addition, the density functional theory approaches were used for theoretical identification of the complex. A good agreement between the computed and experimental infrared frequencies demonstrates validity of the optimized geometry for the synthesized complex. In a N2 O2 manner, two azomethine nitrogens and two phenolate oxygens of the L2- ligand are coordinated to the Mn2+ metal ion. The biological studies indicate an efficient apoptotic and antioxidant activities of the synthesized [MnL(CH3 OH)2 ] complex on both of the HepG2 and MCF7 cancer cells. Since it has been suggested that the complex is an exclusive potent antitumor for treatment of the human breast and liver cancers.
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Affiliation(s)
- Zohreh S Tabatabayi
- Department of Biology, Mashhad Branch, Islamic Azad University, Mashhad, Iran
| | | | - Ali Neamati
- Department of Biology, Mashhad Branch, Islamic Azad University, Mashhad, Iran
| | - S Ali Beyramabadi
- Department of Chemistry, Mashhad Branch, Islamic Azad University, Mashhad, Iran
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Matsuo T, Sadzuka Y. In Vitro Anticancer Activities of B 6 Vitamers: A Mini-review. Anticancer Res 2019; 39:3429-3432. [PMID: 31262866 DOI: 10.21873/anticanres.13488] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 04/08/2019] [Accepted: 04/09/2019] [Indexed: 11/10/2022]
Abstract
Vitamin B6 compounds, including pyridoxine, pyridoxal, pyridoxamine, and their phosphorylated forms, have been investigated with regard to their cancer preventive and therapeutic effects through epidemiological, in vivo, and in vitro studies. In particular, in vitro studies in cancer cells have evaluated the effects of several B6 vitamers such as pyridoxine, pyridoxal, pyridoxamine, and pyridoxal-5'-phosphate, which is a bioactive form of vitamin B6 However, the anticancer activity and concentration required to influence cancer cells vary among B6 vitamers. In this review, the various in vitro effects of vitamin B6 compounds on cancer cells are presented and discussed.
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Affiliation(s)
- Taisuke Matsuo
- Division of Advanced Pharmaceutics, Department of Clinical Pharmaceutical Sciences, School of Pharmacy, Iwate Medical University, Iwate, Japan
| | - Yasuyuki Sadzuka
- Division of Advanced Pharmaceutics, Department of Clinical Pharmaceutical Sciences, School of Pharmacy, Iwate Medical University, Iwate, Japan
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Deka G, Kalyani JN, Jahangir FB, Sabharwal P, Savithri HS, Murthy MRN. Structural and functional studies on Salmonella typhimurium pyridoxal kinase: the first structural evidence for the formation of Schiff base with the substrate. FEBS J 2019; 286:3684-3700. [PMID: 31116912 DOI: 10.1111/febs.14933] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 02/07/2019] [Accepted: 05/20/2019] [Indexed: 11/29/2022]
Abstract
A large number of enzymes depend on the ubiquitous cofactor pyridoxal 5' phosphate (PLP) for their activity. Pyridoxal kinase (PLK) is the key enzyme involved in the synthesis of PLP from the three forms of vitamin B6 via the salvage pathway. In the present work, we determined the unliganded structure of StPLK in a monoclinic form and its ternary complex with bound pyridoxal (PL), ADP and Mg2+ in two different tetragonal crystal forms (Form I and Form II). We found that, in the ternary complex structure of StPLK, the active site Lys233 forms a Schiff base linkage with the substrate (PL). Although formation of a Schiff base with the active site Lys229 was demonstrated in the Escherichia coli enzyme based on biochemical studies, the ternary complex of StPLK represents the first crystal structure where the Schiff bond formation has been observed. We also identified an additional site for PLP binding away from the active site in one of the ternary complexes (crystal Form I), suggesting a probable route for the product release. This is the first ternary complex structure where the modeled γ-phosphate of ATP is close enough to PL for the phosphorylation of the substrate. StPLK prefers PL over pyridoxamine as its substrate and follows a sequential mechanism of catalysis. Surface plasmon resonance studies suggest that StPLK interacts with apo-PLP-dependent enzymes with μm affinity supporting the earlier proposed direct transfer mechanism of PLP from PLK to PLP-dependent enzymes.
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Affiliation(s)
- Geeta Deka
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
| | - Josyula N Kalyani
- Biochemistry Department, Indian Institute of Science, Bangalore, India
| | | | - Pallavi Sabharwal
- Biochemistry Department, Indian Institute of Science, Bangalore, India
| | | | - Mathur R N Murthy
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
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Odai T, Terauchi M, Hirose A, Kato K, Akiyoshi M, Miyasaka N. Severity of hot flushes is inversely associated with dietary intake of vitamin B 6 and oily fish. Climacteric 2019; 22:617-621. [PMID: 31104511 DOI: 10.1080/13697137.2019.1609440] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Objectives: This study investigated the links between the severity of vasomotor symptoms (VMS) and the dietary consumption of a variety of nutrients. Method: A cross-sectional analysis of the first-visit records of 262 women aged 40-65 years was conducted. The severity of their hot flushes (HF) and night sweats (NS) and their dietary consumption of nutrients were evaluated using the Menopausal Health-Related Quality of Life Questionnaire and the brief-type self-administered Diet History Questionnaire, respectively. The relationships between severity of HF/NS and dietary intake were analyzed separately for 43 major nutrients. We then evaluated different food items as sources of the nutrients. Results: After adjustment for age, body mass index, menopausal status, and background factors significantly related to VMS, only vitamin B6 (VB6) was significantly related to severity of HF (adjusted odds ratio per 10 μg/MJ in VB6 intake, 0.92; 95% confidence interval, 0.86-0.97). Moreover, a significant inverse relationship was found between the consumption of oily fish as a source of VB6 and the severity of HF. Conclusions: VB6 and oily fish intake is inversely associated with the severity of HF in middle-aged women. Therefore, increased intake of VB6 could help attenuate HF.
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Affiliation(s)
- T Odai
- Department of Obstetrics and Gynecology, Tokyo Medical and Dental University , Tokyo , Japan
| | - M Terauchi
- Department of Women's Health, Tokyo Medical and Dental University , Tokyo , Japan
| | - A Hirose
- Department of Obstetrics and Gynecology, Tokyo Medical and Dental University , Tokyo , Japan.,Department of Women's Health, Tokyo Medical and Dental University , Tokyo , Japan
| | - K Kato
- Department of Women's Health, Tokyo Medical and Dental University , Tokyo , Japan
| | - M Akiyoshi
- Department of Obstetrics and Gynecology, Tokyo Medical and Dental University , Tokyo , Japan
| | - N Miyasaka
- Department of Obstetrics and Gynecology, Tokyo Medical and Dental University , Tokyo , Japan
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Bachmann T, Rychlik M. Synthesis of [ 13C₃]-B6 Vitamers Labelled at Three Consecutive Positions Starting from [ 13C₃]-Propionic Acid. Molecules 2018; 23:E2117. [PMID: 30142892 DOI: 10.3390/molecules23092117] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 08/16/2018] [Accepted: 08/18/2018] [Indexed: 12/31/2022]
Abstract
[13C3]-labelled vitamers (PN, PL and PM) of the B6 group were prepared starting from [13C3]-propionic acid. [13C3]-PN was synthesized in ten linear steps with an overall yield of 17%. Hereby, higher alkyl homologues of involved esters showed a positive impact on the reaction outcome of the intermediates in the chosen synthetic route. Oxidation of [13C3]-PN to [13C3]-PL was undertaken using potassium permanganate and methylamine followed by acid hydrolysis of the imine derivative. [13C3]-PM could be prepared from the oxime derivative of [13C3]-PN by hydrogenation with palladium.
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Matsuo T, Fujiwara A, Nakamura K, Sadzuka Y. The effects of vitamin B 6 compounds on cell proliferation and melanogenesis in B16F10 melanoma cells. Oncol Lett 2018; 15:5181-5184. [PMID: 29552155 DOI: 10.3892/ol.2018.7947] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 01/23/2018] [Indexed: 11/05/2022] Open
Abstract
B16F10 murine melanoma cells are frequently used for the study of cancer and melanogenesis. The cells are usually cultured in Dulbecco's Modified Eagle Medium, with the addition of 20 µM pyridoxal (PL) or pyridoxine (PN) for vitamin B6. The difference between these vitamin B6 compounds is thought not to affect cell proliferation, whereas their influence on other physiological effects is poorly understood. In the present study, the effects of PL and PN on cell proliferation and melanogenesis in B16F10 cells were compared. At 500 µM PL significantly suppressed cell growth but the growth inhibitory effect of PN was weak. Although neither of the vitamin B6 compounds affected cell growth at 20 µM, melanogenesis was suppressed by 20 µM PL compared with the effect of PN. In addition, the expression levels of tyrosinase, which is the rate-limiting enzyme, correlated with the melanin content. The results of the present study indicate that PL may be more useful for melanoma therapy and suppression of skin pigmentation than PN. The results also signify the importance of medium selection for cell culture.
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Affiliation(s)
- Taisuke Matsuo
- Department of Advanced Pharmaceutics, School of Pharmacy, Iwate Medical University, Shiwa-gun, Iwate 028-3694, Japan
| | - Aki Fujiwara
- Department of Advanced Pharmaceutics, School of Pharmacy, Iwate Medical University, Shiwa-gun, Iwate 028-3694, Japan
| | - Kazuhiro Nakamura
- Department of Advanced Pharmaceutics, School of Pharmacy, Iwate Medical University, Shiwa-gun, Iwate 028-3694, Japan
| | - Yasuyuki Sadzuka
- Department of Advanced Pharmaceutics, School of Pharmacy, Iwate Medical University, Shiwa-gun, Iwate 028-3694, Japan
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Sobczyk L, Chudoba D, Tolstoy PM, Filarowski A. Some Brief Notes on Theoretical and Experimental Investigations of Intramolecular Hydrogen Bonding. Molecules 2016; 21:E1657. [PMID: 27918442 PMCID: PMC6273268 DOI: 10.3390/molecules21121657] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2016] [Revised: 11/18/2016] [Accepted: 11/28/2016] [Indexed: 11/16/2022] Open
Abstract
A review of selected literature data related to intramolecular hydrogen bonding in ortho-hydroxyaryl Schiff bases, ortho-hydroxyaryl ketones, ortho-hydroxyaryl amides, proton sponges and ortho-hydroxyaryl Mannich bases is presented. The paper reports on the application of experimental spectroscopic measurements (IR and NMR) and quantum-mechanical calculations for investigations of the proton transfer processes, the potential energy curves, tautomeric equilibrium, aromaticity etc. Finally, the equilibrium between the intra- and inter-molecular hydrogen bonds in amides is discussed.
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Affiliation(s)
- Lucjan Sobczyk
- Faculty of Chemistry, University of Wrocław, 14 F. Joliot-Curie Str., 50-383 Wrocław, Poland.
| | - Dorota Chudoba
- Faculty of Physics, A. Mickiewicz University, Umultowska 85, 61-614 Poznan, Poland.
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, 141980 Dubna, Russia.
| | - Peter M Tolstoy
- Center for Magnetic Resonance, St. Petersburg State University, St. Petersburg 198504, Russia.
| | - Aleksander Filarowski
- Faculty of Chemistry, University of Wrocław, 14 F. Joliot-Curie Str., 50-383 Wrocław, Poland.
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, 141980 Dubna, Russia.
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Carter TC, Pangilinan F, Molloy AM, Fan R, Wang Y, Shane B, Gibney ER, Midttun Ø, Ueland PM, Cropp CD, Kim Y, Wilson AF, Bailey-Wilson JE, Brody LC, Mills JL. Common Variants at Putative Regulatory Sites of the Tissue Nonspecific Alkaline Phosphatase Gene Influence Circulating Pyridoxal 5'-Phosphate Concentration in Healthy Adults. J Nutr 2015; 145:1386-93. [PMID: 25972531 PMCID: PMC4478949 DOI: 10.3945/jn.114.208769] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Accepted: 04/13/2015] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Vitamin B-6 interconversion enzymes are important for supplying pyridoxal 5'-phosphate (PLP), the co-enzyme form, to tissues. Variants in the genes for these enzymes [tissue nonspecific alkaline phosphatase (ALPL), pyridoxamine 5'-phosphate oxidase, pyridoxal kinase, and pyridoxal phosphatase] could affect enzyme function and vitamin B-6 status. OBJECTIVES We tested whether single-nucleotide polymorphisms (SNPs) in these genes influence vitamin B-6 status markers [plasma PLP, pyridoxal (PL), and 4-pyridoxic acid (PA)], and explored potential functional effects of the SNPs. METHODS Study subjects were young, healthy adults from Ireland (n = 2345). We measured plasma PLP, PL, and PA with liquid chromatography-tandem mass spectrometry and genotyped 66 tag SNPs in the 4 genes. We tested for associations with single SNPs in candidate genes and also performed genome-wide association study (GWAS) and gene-based analyses. RESULTS Seventeen SNPs in ALPL were associated with altered plasma PLP in candidate gene analyses (P < 1.89 × 10(-4)). In the GWAS, 5 additional ALPL SNPs were associated with altered plasma PLP (P < 5.0 × 10(-8)). Gene-based analyses that used the functional linear model β-spline (P = 4.04 × 10(-15)) and Fourier spline (P = 5.87 × 10(-15)) methods also showed associations between ALPL and altered plasma PLP. No SNPs in other genes were associated with plasma PLP. The association of the minor CC genotype of 1 ALPL SNP, rs1256341, with reduced ALPL expression in the HapMap Northern European ancestry population is consistent with the positive association between the CC genotype and plasma PLP in our study (P = 0.008). No SNP was associated with altered plasma PL or PA. CONCLUSIONS In healthy adults, common variants in ALPL influence plasma PLP concentration, the most frequently used biomarker for vitamin B-6 status. Whether these associations are indicative of functional changes in vitamin B-6 status requires more investigation.
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Affiliation(s)
- Tonia C Carter
- Center for Human Genetics, Marshfield Clinic, Marshfield, WI
| | | | - Anne M Molloy
- Institute of Molecular Medicine, School of Medicine, Trinity College Dublin, Dublin, Ireland
| | - Ruzong Fan
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, MD
| | - Yifan Wang
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, MD
| | - Barry Shane
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, Berkeley, CA
| | - Eileen R Gibney
- UCD Institute of Food and Health, University College Dublin, Dublin, Ireland
| | | | - Per M Ueland
- Department of Clinical Science, University of Bergen, Bergen, Norway
| | | | | | | | | | | | - James L Mills
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, MD;
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Astegno A, Allegrini A, Piccoli S, Giorgetti A, Dominici P. Role of active-site residues Tyr55 and Tyr114 in catalysis and substrate specificity of Corynebacterium diphtheriae C-S lyase. Proteins 2014; 83:78-90. [PMID: 25354840 DOI: 10.1002/prot.24707] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 09/29/2014] [Accepted: 10/18/2014] [Indexed: 11/07/2022]
Abstract
In recent years, there has been increased interest in bacterial methionine biosynthesis enzymes as antimicrobial targets because of their pivotal role in cell metabolism. C-S lyase from Corynebacterium diphtheriae is a pyridoxal 5'-phosphate-dependent enzyme in the transsulfuration pathway that catalyzes the α,β-elimination of sulfur-containing amino acids, such as L-cystathionine, to generate ammonia, pyruvate, and homocysteine, the immediate precursor of L-methionine. In order to gain deeper insight into the functional and dynamic properties of the enzyme, mutants of two highly conserved active-site residues, Y55F and Y114F, were characterized by UV-visible absorbance, fluorescence, and CD spectroscopy in the absence and presence of substrates and substrate analogs, as well as by steady-state kinetic studies. Substitution of Tyr55 with Phe apparently causes a 130-fold decrease in K(d)(PLP) at pH 8.5 providing evidence that Tyr55 plays a role in cofactor binding. Moreover, spectral data show that the mutant accumulates the external aldimine intermediate suggesting that the absence of interaction between the hydroxyl moiety and PLP-binding residue Lys222 causes a decrease in the rate of substrate deprotonation. Mutation of Tyr114 with Phe slightly influences hydrolysis of L-cystathionine, and causes a change in substrate specificity towards L-serine and O-acetyl-L-serine compared to the wild type enzyme. These findings, together with computational data, provide useful insights in the substrate specificity of C-S lyase, which seems to be regulated by active-site architecture and by the specific conformation in which substrates are bound, and will aid in development of inhibitors.
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Affiliation(s)
- Alessandra Astegno
- Department of Biotechnology, University of Verona, Strada Le Grazie 15, Verona, Italy
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Katsuta N, Ohnuma T, Maeshima H, Takebayashi Y, Higa M, Takeda M, Nakamura T, Nishimon S, Sannohe T, Hotta Y, Hanzawa R, Higashiyama R, Shibata N, Arai H. Significance of measurements of peripheral carbonyl stress markers in a cross-sectional and longitudinal study in patients with acute-stage schizophrenia. Schizophr Bull 2014; 40:1366-73. [PMID: 24448481 PMCID: PMC4193703 DOI: 10.1093/schbul/sbt234] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Altered peripheral carbonyl stress markers, high levels of serum pentosidine, which accumulates following carbonyl stress, and low levels of pyridoxal (vitamin B6), which detoxifies reactive carbonyl compounds, have been reported in a cross-sectional study of chronic schizophrenia. However, changes in the levels of these compounds in patients with schizophrenia have not been investigated in a longitudinal study. To clarify whether these markers may be biological markers that reflect the clinical course of the disease, the serum levels of these compounds were investigated in a cross-sectional and a longitudinal study. One hundred and thirty-seven acute-stage Japanese patients were enrolled. Among these, 53 patients were followed from the acute stage to remission. A portion of patients in the acute stage (14 cases, 10.2%) showed extremely high pentosidine levels. These levels were not associated with the severity of symptoms but were associated with antipsychotic dose amounts. Pyridoxal levels were lower in schizophrenia and increased according to the clinical course of the illness. Furthermore, 18 patients with decreased pyridoxal levels according to the clinical course showed that the greater the decrease in pyridoxal levels, the lesser the improvement in symptoms. Thus, extremely high pentosidine levels in a portion of patients may be caused by higher daily antipsychotic doses, whereas pyridoxal levels were lower in schizophrenia and increased according to the clinical course. Patients with decreasing pyridoxal levels during the clinical course showed less improvement in symptoms. Carbonyl stress markers may also be therapeutic biological markers in some patients with schizophrenia.
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Affiliation(s)
| | - Tohru Ohnuma
- Department of Psychiatry, Juntendo University School of Medicine, Tokyo, Japan
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Abstract
Appropriate biological treatment and psychosocial support are essential to achieve and maintain recovery for patients with schizophrenia. Despite extensive efforts to clarify the underlying disease mechanisms, the main cause and pathophysiology of schizophrenia remain unclear. This is due in large part to disease heterogeneity, which results in biochemical differences within a single disease entity. Other factors include variability across clinical symptoms and disease course, along with varied risk factors and treatment responses. Although schizophrenia's positive symptoms are largely managed through treatment with atypical antipsychotics, new classes of drugs are needed to address the unmet medical need for improving cognitive dysfunction and promoting recovery of negative symptoms in these patients. Accumulation of toxic reactive dicarbonyls, such as methylglyoxal, are typical indicators of carbonyl stress, and result in the modification of proteins and the formation of advanced glycation end products, such as pentosidine. In June 2010, we reported on idiopathic carbonyl stress in a subpopulation of schizophrenia patients, leading to a failure of metabolic systems with plasma pentosidine accumulation and serum pyridoxal depletion. Our findings suggest two markers, pentosidine and pyridoxal, as beneficial for distinguishing a specific subgroup of schizophrenics. We believe that this information, derived from in vitro and in vivo studies, is beneficial in the search for personalized and hopefully more effective treatment regimens in schizophrenia. Here, we define a subtype of schizophrenia based on carbonyl stress and the potential for using carbonyl stress as a biomarker in the challenge of overcoming heterogeneity in schizophrenia treatment.
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Affiliation(s)
- Makoto Arai
- Department of Psychiatry and Behavioral Sciences, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
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26
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Uram Ł, Szuster M, Gargasz K, Filipowicz A, Wałajtys-Rode E, Wołowiec S. In vitro cytotoxicity of the ternary PAMAM G3- pyridoxal-biotin bioconjugate. Int J Nanomedicine 2013; 8:4707-20. [PMID: 24376351 PMCID: PMC3864882 DOI: 10.2147/ijn.s53254] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
A third-generation polyamidoamine dendrimer (PAMAM G3) was used as a macromolecular carrier for pyridoxal and biotin. The binary covalent bioconjugate of G3, with nine molecules of biotin per one molecule of G3 (G39B), and the ternary covalent bioconjugate of G3, with nine biotin and ten pyridoxal molecules (G39B10P), were synthesized. The biotin and pyridoxal residues of the bioconjugate were available for carboxylase and transaminase enzymes, as demonstrated in the conversion of pyruvate to oxaloacetate and alanine to pyruvate, respectively, by in vitro monitoring of the reactions, using 1H nuclear magnetic resonance spectroscopy. The toxicity of the ternary bioconjugate (BC-PAMAM) was studied in vitro on BJ human normal skin fibroblasts and human squamous cell carcinoma (SCC-15) cell cultures in comparison with PAMAM G3, using three cytotoxicity assays (XTT, neutral red, and crystal violet) and an estimation of apoptosis by confocal microscopy detection. The tests have shown that BC-PAMAM has significantly lower cytotoxicity compared with PAMAM. Nonconjugated PAMAM was not cytotoxic at concentrations up to 5 μM (NR) and 10 μM (XTT), and BC-PAMAM was not cytotoxic up to 50 μM (both assays) for both cell lines. It has been also found that normal fibroblasts were more sensitive than SCC to both PAMAM and BC-PAMAM. The effect of PAMAM and BC-PAMAM on the initiation of apoptosis (PAMAM in fibroblasts at 5 μM and BC-PAMAM at 10 μM in both cell lines) corresponded with cytotoxicity assays for both cell lines. We concluded that normal fibroblasts are more sensitive to the cytotoxic effects of the PAMAM G3 dendrimer and that modification of its surface cationic groups by substitution with biologically active molecules significantly decreases that effect, confirming that PAMAM G3 is a useful candidate as a carrier for active biocompound delivery.
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Affiliation(s)
- Łukasz Uram
- Cosmetology Department, University of Information Technology and Management in Rzeszów, Rzeszów, Poland
| | - Magdalena Szuster
- Cosmetology Department, University of Information Technology and Management in Rzeszów, Rzeszów, Poland
| | - Krzysztof Gargasz
- Cosmetology Department, University of Information Technology and Management in Rzeszów, Rzeszów, Poland
| | - Aleksandra Filipowicz
- Cosmetology Department, University of Information Technology and Management in Rzeszów, Rzeszów, Poland
| | - Elżbieta Wałajtys-Rode
- Cosmetology Department, University of Information Technology and Management in Rzeszów, Rzeszów, Poland
| | - Stanisław Wołowiec
- Cosmetology Department, University of Information Technology and Management in Rzeszów, Rzeszów, Poland
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27
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Abstract
Background Bioconjugates of a polyamidoamine (PAMAM) G3 dendrimer and an aldehyde were synthesized as carriers for vitamins A and B6, and the bioavailability of these vitamins for skin nutrition was investigated. Methods Nuclear magnetic resonance (NMR) and ultraviolet-visible methods were used to characterize the structure of the bioconjugates and for monitoring release of pyridoxal (Pyr) and pyridoxal phosphate (PLP) from these bioconjugates in vitro. A skin model permeation of bioconjugates was also studied in a Franz chamber. Results A transdermal G3 PAMAM dendrimer was used to synthesize bioconjugates with trans-retinal (Ret), pyridoxal (Pyr), or PLP. These nanomolecules, containing up to four covalently linked Ret, Pyr, or PLP (G34Ret, G34Pyr, and G34PLP), were able to permeate the skin, as demonstrated in vitro using a model skin membrane. PLP and Pyr bound to a macromolecular vehicle were active cofactors for glutamic pyruvic transaminase, as shown by 1H NMR spectral monitoring of the progress of the L-alanine + α-ketoglutarate → glutamic acid + pyruvic acid reaction. Conclusion PAMAM-PLP, PAMAM-Pyr, and PAMAM-Ret bioconjugates are able to permeate the skin. PLP and Pyr are available as cofactors for glutamic pyruvic transaminase.
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Affiliation(s)
- A Filipowicz
- Department of Cosmetology, University of Information Technology and Management in Rzeszów, Rzeszów, Poland
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28
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Abstract
Background There is a need for a reliable and accurate method for quantification of each of the seven individual vitamin B6 compounds including pyridoxine-β-glucoside in foods. Objective To determine pyridoxal (PL), pyridoxamine (PM), pyridoxine (PN), pyridoxal 5′-phosphate (PLP), pyridoxamine 5′-phosphate (PMP), pyridoxine 5′-phosphate (PNP), and pyridoxine-β-glucoside (PNG) in foods. Design By specific enzymatic treatment, each of the seven vitamin B6 compounds was all converted into 4-pyridoxolactone, which is a highly fluorescent compound. In total, seven separate, enzymatic steps were performed for each sample. Separation and quantification were performed with reversed-phase high performance liquid chromatography (HPLC) coupled with fluorescence detection. For each sample type the result was corrected for the recovery based on spiked samples. The method was applied for analyses of chicken liver, chicken white meat, egg yolk, egg white, dried anchovy, carrots, and garlic. Results The recovery varied from 14 to 114% in chicken liver, chicken white meat, egg yolk, egg white, dried anchovy, carrot, and garlic. Each food showed a characteristic distribution of the seven vitamin B6 compounds. The PNG was only found in low amounts; that is, 17–29nmol vitamin B6/g in the plant-derived foods, carrot and garlic. Only egg white showed a lower content, 3nmol/g. Overall the content in chicken liver, chicken white meat, and egg yolk had a total content of vitamin B6 between 42 and 51nmol/g. Both PM and PMP were high in the chicken liver. In contrast, PL and PLP were high in the chicken white meat. The main vitamin B6 in the egg yolk was PLP. The dried anchovy contained high amounts of PLP and PMP and a total content of 144nmol/g. Conclusions The enzymatic-based HPLC method was applied for the determination of seven vitamin B6 compounds in foods. Their distribution in the foods varied significantly.
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Affiliation(s)
- Huong Thi Viet Do
- Faculty of Agriculture and Agricultural Science Program, Graduate School of Integrated Arts and Sciences, Kochi University, Nankoku, Kochi, Japan
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Mugo AN, Kobayashi J, Mikami B, Ohnishi K, Yagi T. Crystallization and preliminary X-ray analysis of pyridoxine 4-oxidase, the first enzyme in pyridoxine degradation pathway I. Acta Crystallogr Sect F Struct Biol Cryst Commun 2012; 68:66-68. [PMID: 22232175 PMCID: PMC3253838 DOI: 10.1107/s1744309111048688] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Accepted: 11/16/2011] [Indexed: 05/31/2023]
Abstract
Vitamin B(6)-degradation pathway I has recently been identified in Mesorhizobium loti MAFF303099. Pyridoxine 4-oxidase, an FAD-dependent enzyme, is the first enzyme in this pathway and catalyzes the irreversible oxidation of pyridoxine to pyridoxal. The enzyme was overexpressed in Escherichia coli with a His(6) tag and purified. The recombinant enzyme was crystallized at 277 K by the sitting-drop vapour-diffusion method using PEG 4000 as the precipitant. The crystal, which belonged to space group P2(1)2(1)2(1) with unit-cell parameters a = 62.38, b = 79.44, c = 136.43 Å, diffracted to 2.2 Å resolution. The calculated V(M) value (3.19 Å(3) Da(-1)) suggested that the asymmetric unit contained one molecule.
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Affiliation(s)
- Andrew Njagi Mugo
- Faculty of Agriculture and Agricultural Science Program, Graduate School of Integral Arts and Science, Kochi University, Nankoku, Kochi 783-8502, Japan
| | - Jun Kobayashi
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Bunzo Mikami
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Kouhei Ohnishi
- Research Institute of Molecular Genetics, Kochi University, Nankoku, Kochi 783-8502, Japan
| | - Toshiharu Yagi
- Faculty of Agriculture and Agricultural Science Program, Graduate School of Integral Arts and Science, Kochi University, Nankoku, Kochi 783-8502, Japan
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30
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Abstract
A mutant of Salmonella typhimurium LT-2 that requires either vitamin B(6) or histidine for growth was found to synthesize vitamin B(5) in amounts comparable to the parent strain, but to be deficient in imidazoleacetol phosphate transaminase (L-histidinolphosphate: 2-oxoglutarate aminotransferase, EC 2.6.1.9), an enzyme required for histidine biosynthesis. The mutant apotransaminase required a 50-fold higher concentration of pyridoxal 5'-phosphate for half-maximum activation than the corresponding wild-type enzyme; the fully activated mutant enzyme also displays a much lower maximum rate of catalysis than the enzyme from the parent strain. Such mutational changes in bacteria resemble those in certain vitamin B(6)-responsive genetic diseases in man and provide useful experimental material for the study of factors involved in coenzyme binding and enzymatic catalysis.
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