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Baderdin S, Janousek J, Brandstaetter H, Morley N, Weber L, Sobańtka A. Impact of formaldehyde, acetaldehyde, and N-(3-(Dimethylamino)propyl)methacrylamide on the efficacy of the human derived coagulation factor IX. Int J Pharm 2023; 634:122664. [PMID: 36738809 DOI: 10.1016/j.ijpharm.2023.122664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 01/26/2023] [Accepted: 01/27/2023] [Indexed: 02/05/2023]
Abstract
Polymer-borne leachables such as formaldehyde, acetaldehyde, and N-3-(Dimethylamino)propyl)methacrylamide (DMAPMA) may interact with therapeutic proteins. In this study, the leachables were spiked into human derived coagulation factor IX (FIX) at concentrations of 1, 10, 50, 100, and 500 µg/mL, corresponding to a leachable - FIX ratio of 0.5, 5, 25, 50 and 250 %, respectively. The spiked samples were visually inspected, and pH was measured. No visual effects were observed, and pH was within the drug product's specified range. Recovery experiments were performed and no loss of leachables was identified. Protein structure analysis revealed that formaldehyde reacted with lysine contained in two different positions of FIX, in a concentration-dependent manner starting at 10 µg/mL (5 %). The clotting activity of FIX was measured. The activity of the samples spiked with 500 µg/mL (250 %) of formaldehyde dropped by more than half. The activity of the samples spiked with acetaldehyde began to drop at 50 µg/mL (25 %) and continued to decline in concentration-dependent manner. DMAPMA did not impair the activity of FIX. The findings conclude that depending on the concentration, some leachables may react with or modify therapeutic proteins, potentially causing an undesired pharmacological effect however, this is specific to each protein.
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Affiliation(s)
- Sally Baderdin
- Octapharma Pharmazeutika Produktionsges.m.b.H, Department of Manufacturing Science and Technology, Vienna, Austria
| | - Janine Janousek
- Octapharma Pharmazeutika Produktionsges.m.b.H, Department of Manufacturing Science and Technology, Vienna, Austria
| | | | | | - Lisa Weber
- A&M Stabtest Labor für Analytik und Stabilitätsprüfung GmbH, Bergheim, Germany
| | - Alicja Sobańtka
- Octapharma Pharmazeutika Produktionsges.m.b.H, Department of Manufacturing Science and Technology, Vienna, Austria.
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2
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Identification of Formaldehyde-Induced Modifications in Diphtheria Toxin. J Pharm Sci 2019; 109:543-557. [PMID: 31678246 DOI: 10.1016/j.xphs.2019.10.047] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 10/17/2019] [Accepted: 10/28/2019] [Indexed: 01/08/2023]
Abstract
Diphtheria toxoid is produced by detoxification of diphtheria toxin with formaldehyde. This study was performed to elucidate the chemical nature and location of formaldehyde-induced modifications in diphtheria toxoid. Diphtheria toxin was chemically modified using 4 different reactions with the following reagents: (1) formaldehyde and NaCNBH3, (2) formaldehyde, (3) formaldehyde and NaCNBH3 followed by formaldehyde and glycine, and (4) formaldehyde and glycine. The modifications were studied by SDS-PAGE, primary amino group determination, and liquid chromatography-electrospray mass spectrometry of chymotryptic digests. Reaction 1 resulted in quantitative dimethylation of all lysine residues. Reaction 2 caused intramolecular cross-links, including the NAD+-binding cavity and the receptor-binding site. Moreover, A fragments and B fragments were cross-linked by formaldehyde on part of the diphtheria toxoid molecules. Reaction 3 resulted in formaldehyde-glycine attachments, including in shielded areas of the protein. The detoxification reaction typically used for vaccine preparation (reaction 4) resulted in a combination of intramolecular cross-links and formaldehyde-glycine attachments. Both the NAD+-binding cavity and the receptor-binding site of diphtheria toxin were chemically modified. Although CD4+ T-cell epitopes were affected to some extent, one universal CD4+ T-cell epitope remained almost completely unaltered by the treatment with formaldehyde and glycine.
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Kalgutkar AS. Liabilities Associated with the Formation of “Hard” Electrophiles in Reactive Metabolite Trapping Screens. Chem Res Toxicol 2016; 30:220-238. [DOI: 10.1021/acs.chemrestox.6b00332] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Amit S. Kalgutkar
- Pharmacokinetics, Dynamics, and Metabolism − New Chemical
Entities, Pfizer Worldwide Research and Development, 610 Main
Street, Cambridge, Massachusetts 02139, United States
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Mortera SL, Dioni I, Greco V, Neri C, Rovero P, Urbani A. pH-regulated formation of side products in the reductive amination approach for differential labeling of peptides in relative quantitative experiments. Electrophoresis 2014; 35:1259-67. [DOI: 10.1002/elps.201300484] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Stefano Levi Mortera
- Department of System Medicine; University of Rome Tor Vergata; Rome Italy
- Proteomic and Metabonomic Laboratory; Santa Lucia Foundation; Rome Italy
| | - Ilaria Dioni
- Section of Pharmaceutical Sciences and Nutraceutics; Department NeuroFarBa; Laboratory of Peptide and Protein Chemistry and Biology; University of Florence; Florence Italy
| | - Viviana Greco
- Proteomic and Metabonomic Laboratory; Santa Lucia Foundation; Rome Italy
| | - Cristina Neri
- Proteomic and Metabonomic Laboratory; Santa Lucia Foundation; Rome Italy
| | - Paolo Rovero
- Section of Pharmaceutical Sciences and Nutraceutics; Department NeuroFarBa; Laboratory of Peptide and Protein Chemistry and Biology; University of Florence; Florence Italy
| | - Andrea Urbani
- Department of System Medicine; University of Rome Tor Vergata; Rome Italy
- Proteomic and Metabonomic Laboratory; Santa Lucia Foundation; Rome Italy
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5
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Limami AM. Adaptations of Nitrogen Metabolism to Oxygen Deprivation in Plants. LOW-OXYGEN STRESS IN PLANTS 2014. [DOI: 10.1007/978-3-7091-1254-0_11] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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6
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Feng X, Chen L, Zhuang S, Li C, Yan Z, Xu X, Zhou G. Effect of duck meat consumption on thyroid hormone concentrations and energy metabolism of Sprague–Dawley rats. Appetite 2013; 69:94-101. [DOI: 10.1016/j.appet.2013.04.027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Revised: 04/21/2013] [Accepted: 04/29/2013] [Indexed: 02/02/2023]
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Szachowicz-Petelska B, Skrzydlewska E, Figaszewski Z. Protective effect of black tea on integral membrane proteins in rat liver. ACTA ACUST UNITED AC 2013; 65:173-9. [DOI: 10.1016/j.etp.2011.08.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2010] [Revised: 06/14/2011] [Accepted: 08/18/2011] [Indexed: 01/14/2023]
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8
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A comparative DFT study of the Schiff base formation from acetaldehyde and butylamine, glycine and phosphatidylethanolamine. Theor Chem Acc 2012. [DOI: 10.1007/s00214-012-1263-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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9
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Tan H, Rubin JP, Marra KG. Injectable in situ forming biodegradable chitosan-hyaluronic acid based hydrogels for adipose tissue regeneration. Organogenesis 2011; 6:173-80. [PMID: 21197220 DOI: 10.4161/org.6.3.12037] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2010] [Accepted: 04/12/2010] [Indexed: 12/22/2022] Open
Abstract
An injectable, biodegradable and glucose-responsive hydrogel derived from natural polysaccharide derivatives was synthesized to deliver adipogenic factor of insulin in vitro for adipose tissue engineering. The biodegradable hydrogel based N-succinyl-chitosan (SCS) and aldehyde hyaluronic acid (AHA) with covalently conjugated glucose oxidase and catalase. The gelation is attributed to the Schiff-base reaction between amino and aldehyde groups of SCS and AHA, respectively. The morphologies and compressive modulus of the freeze-dried hydrogels demonstrated that the incorporated insulin and enzymes results in the formation of a tighter network structure in composite hydrogels. The immobilized enzymes triggered conversion of glucose reduces the pH value of the microenvironment, and results in hydrolysis and increasing swelling of the network basing on Schiff-base cross-linking. The pH inside the hydrogel, kept in PBS solution at pH 7.4 and 37°C, linearly dropped from 7.40 to 7.17 during 4 h of initial period, then slowly increased to 7.36 after 24 h. Correspondingly, the swelling ratio increased from 20.8 to 28.6 at 37°C in PBS with 500 mg/dL glucose. In PBS buffer with 500 mg/dL glucose, about 10.8% of insulin was released from the hydrogel after 8 h of incubation while upon observation. The results demonstrated that the adipogenic factor of insulin would be released from this biodegradable hydrogel device into the local microenvironment in a controlled fashion by the swelling of hydrogel network. These preliminary studies indicate that the biodegradable and glucose-responsive hydrogel may have potential uses in adipose tissue engineering applications.
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Affiliation(s)
- Huaping Tan
- Division of Plastic Surgery, Department of Surgery, University of Pittsburgh, Pittsburgh, PA, USA
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Toennes SW, Wagner MG, Kauert GF. Application of LC–TOF MS to analysis of hemoglobin acetaldehyde adducts in alcohol detoxification patients. Anal Bioanal Chem 2010; 398:769-77. [DOI: 10.1007/s00216-010-3931-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2010] [Revised: 06/14/2010] [Accepted: 06/15/2010] [Indexed: 11/28/2022]
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Szachowicz-Petelska B, Skrzydlewska E, Figaszewski Z. Changes in Protein Composition in Erythrocyte Membrane of Ethanol—Poisoned Rats After Administration of Teas. ANAL LETT 2010. [DOI: 10.1080/00032710903406979] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Kern KA, Pergo EM, Kagami FL, Arraes LS, Sert MA, Ishii-Iwamoto EL. The phytotoxic effect of exogenous ethanol on Euphorbia heterophylla L. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2009; 47:1095-1101. [PMID: 19640725 DOI: 10.1016/j.plaphy.2009.07.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2008] [Revised: 06/18/2009] [Accepted: 07/05/2009] [Indexed: 05/28/2023]
Abstract
This study investigated the effects of exogenously applied ethanol on Euphorbia heterophylla L., a troublesome weed in field and plantation crops. Ethanol at concentrations ranging from 0.25 to 1.5% caused a dose-dependent inhibition of germination and growth of E. heterophylla. Measurements of respiratory activity and alcohol dehydrogenase (E.C. 1.1.1.1) activity during seed imbibition and initial seedling growth revealed that ethanol induces a prolongation of hypoxic conditions in the growing tissues. In isolated mitochondria, ethanol inhibited the respiration coupled to ADP phosphorylation, an action that probably contributed to modifications observed in the respiratory activity of embryos. A comparison of the effects of methanol, ethanol, propanol and acetaldehyde on germination and growth of E. heterophylla indicates that alcohol dehydrogenase activity is required for the observed effects, with the conversion of ethanol to acetaldehyde playing a role in the ethanol-induced injuries.
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Affiliation(s)
- Kátia Aparecida Kern
- Laboratory of Biological Oxidations, Department of Biochemistry, University of Maringá, 87020900 Maringá, Brazil
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De Benedetto GE, Fanigliulo M. A new CE-ESI-MS method for the detection of stable hemoglobin acetaldehyde adducts, potential biomarkers of alcohol abuse. Electrophoresis 2009; 30:1798-807. [PMID: 19441035 DOI: 10.1002/elps.200800379] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A new CE-ESI-MS method was developed to provide a simple way to study changes to hemoglobin (HbA) induced by acetaldehyde (Ach) in vitro. Instrumental parameters were univariately optimized in order to maximize the sensitivity of the CE-ESI-MS method. The electrophoretic separations were carried out in poly-E323-coated capillaries using 60 mM formic acid raised to pH 3.0 with ammonia and containing 5% 2-propanol while the sheath liquid, 2-propanol/water (30:70) with 0.1% formic acid, was delivered at 1.0 microL/min through a coaxial sheath flow electrospray interface. The HbA was incubated with Ach for intervals up to 24 h at concentration varying in the window 0.2-20 mM. Four stable Ach-hemoglobin adducts in the hemoglobin tryptic digest were observed at the submillimolar Ach concentration and characterized by MS/MS experiments: although the alpha and beta N-amino terminal modifications were expected, the two internal ones arising, respectively, from the condensation of Ach molecules on the histidine residue in position 4 in alpha4 (i.e. the fourth peptide after tryptic digestion of alpha chain starting from amino terminal) and on the asparagine residue in position 2 in beta3, were identified for the first time. During the in vitro experiments higher concentrations of Ach were also used; however, it was not possible to identify any other stable modification of hemoglobin. Interestingly, those stable modifications are the only ones in vivo identified in the hemoglobin of moderate alcohol drinkers.
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Affiliation(s)
- Giuseppe E De Benedetto
- Laboratorio di Analisi Chimiche per l'Ambiente e i Beni Culturali, Dipartimento dei Beni delle Arti e della Storia, Università del Salento, Lecce, Italy.
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Fisher SJ, Swaan PW, Eddington ND. The ethanol metabolite acetaldehyde increases paracellular drug permeability in vitro and oral bioavailability in vivo. J Pharmacol Exp Ther 2009; 332:326-33. [PMID: 19820208 DOI: 10.1124/jpet.109.158642] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Alcohol consumption leads to the production of the highly reactive ethanol metabolite, acetaldehyde, which may affect intestinal tight junctions and increase paracellular permeability. We examined the effects of elevated acetaldehyde within the gastrointestinal tract on the permeability and bioavailability of hydrophilic markers and drug molecules of variable molecular weight and geometry. In vitro permeability was measured unidirectionally in Caco-2 and MDCKII cell models in the presence of acetaldehyde, ethanol, or disulfiram, an aldehyde dehydrogenase inhibitor, which causes acetaldehyde formation when coadministered with ethanol in vivo. Acetaldehyde significantly lowered transepithelial resistance in cell monolayers and increased permeability of the low-molecular-weight markers, mannitol and sucrose; however, permeability of high-molecular-weight markers, polyethylene glycol and inulin, was not affected. In vivo permeability was assessed in male Sprague-Dawley rats treated for 6 days with ethanol, disulfiram, or saline alone or in combination. Bioavailability of naproxen was not affected by any treatment, whereas that of paclitaxel was increased upon acetaldehyde exposure. Although disulfiram has been shown to inhibit multidrug resistance-1 P-glycoprotein (P-gp) in vitro, our data demonstrate that the known P-gp substrate paclitaxel is not affected by coadministration of disulfiram. In conclusion, we demonstrate that acetaldehyde significantly modulates tight junctions and paracellular permeability in vitro as well as the oral bioavailability of low-molecular-weight hydrophilic probes and therapeutic molecules in vivo even when these molecules are substrates for efflux transporters. These studies emphasize the significance of ethanol metabolism and drug interactions outside of the liver.
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Affiliation(s)
- Scott J Fisher
- Department of Pharmaceutical Sciences, University of Maryland, MD 21201, USA
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Millington KR, Ishii H, Maurdev G. Chemiluminescence from thermal oxidation of amino acids and proteins. Amino Acids 2009; 38:1395-405. [DOI: 10.1007/s00726-009-0352-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2009] [Accepted: 09/09/2009] [Indexed: 11/24/2022]
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16
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Bootorabi F, Jänis J, Valjakka J, Isoniemi S, Vainiotalo P, Vullo D, Supuran CT, Waheed A, Sly WS, Niemelä O, Parkkila S. Modification of carbonic anhydrase II with acetaldehyde, the first metabolite of ethanol, leads to decreased enzyme activity. BMC BIOCHEMISTRY 2008; 9:32. [PMID: 19036170 PMCID: PMC2605449 DOI: 10.1186/1471-2091-9-32] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/03/2008] [Accepted: 11/27/2008] [Indexed: 02/08/2023]
Abstract
BACKGROUND Acetaldehyde, the first metabolite of ethanol, can generate covalent modifications of proteins and cellular constituents. However, functional consequences of such modification remain poorly defined. In the present study, we examined acetaldehyde reaction with human carbonic anhydrase (CA) isozyme II, which has several features that make it a suitable target protein: It is widely expressed, its enzymatic activity can be monitored, its structural and catalytic properties are known, and it contains 24 lysine residues, which are accessible sites for aldehyde reaction. RESULTS Acetaldehyde treatment in the absence and presence of a reducing agent (NaBH3(CN)) caused shifts in the pI values of CA II. SDS-PAGE indicated a shift toward a slightly higher molecular mass. High-resolution mass spectra of CA II, measured with and without NaBH3(CN), indicated the presence of an unmodified protein, as expected. Mass spectra of CA II treated with acetaldehyde revealed a modified protein form (+26 Da), consistent with a "Schiff base" formation between acetaldehyde and one of the primary NH2 groups (e.g., in lysine side chain) in the protein structure. This reaction was highly specific, given the relative abundance of over 90% of the modified protein. In reducing conditions, each CA II molecule had reacted with 9-19 (14 on average) acetaldehyde molecules (+28 Da), consistent with further reduction of the "Schiff bases" to substituted amines (N-ethyllysine residues). The acetaldehyde-modified protein showed decreased CA enzymatic activity. CONCLUSION The acetaldehyde-derived modifications in CA II molecule may have physiological consequences in alcoholic patients.
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Affiliation(s)
- Fatemeh Bootorabi
- Institute of Medical Technology, Tampere University Hospital, 33520 Tampere, Finland.
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Chalkley RJ, Baker PR, Medzihradszky KF, Lynn AJ, Burlingame AL. In-depth analysis of tandem mass spectrometry data from disparate instrument types. Mol Cell Proteomics 2008; 7:2386-98. [PMID: 18653769 DOI: 10.1074/mcp.m800021-mcp200] [Citation(s) in RCA: 153] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mass spectrometric analyses of protein digests produce large numbers of fragmentation spectra that are not identified by routine database searching strategies. Some of these spectra could be identified by development of improved search engines. However, many of these spectra represent fragmentation of peptide components bearing modifications that are not routinely considered in database searches. Here we present new software within Protein Prospector that allows comprehensive analysis of data sets by analyzing the data at increasing levels of depth. Analysis of published data sets is presented to illustrate that the software is not biased to any instrument types. The results show that these data sets contain many modified peptides. As well as searching for known modification types, Protein Prospector permits the detection and identification of unexpected or novel modifications by searching for any mass shift within a user-specified mass range to any chosen amino acid(s). Several modifications never previously reported in proteomics data were identified in these standard data sets using this mass modification searching approach.
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Affiliation(s)
- Robert J Chalkley
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California 94158-2517, USA.
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18
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A comparative study of the chemical reactivity of pyridoxamine, Ac-Phe-Lys and Ac-Cys with various glycating carbonyl compounds. Amino Acids 2008; 36:437-48. [DOI: 10.1007/s00726-008-0098-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2008] [Accepted: 04/26/2008] [Indexed: 11/26/2022]
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Limami AM, Glévarec G, Ricoult C, Cliquet JB, Planchet E. Concerted modulation of alanine and glutamate metabolism in young Medicago truncatula seedlings under hypoxic stress. JOURNAL OF EXPERIMENTAL BOTANY 2008; 59:2325-35. [PMID: 18508812 PMCID: PMC2423662 DOI: 10.1093/jxb/ern102] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2008] [Revised: 03/11/2008] [Accepted: 03/11/2008] [Indexed: 05/18/2023]
Abstract
The modulation of primary nitrogen metabolism by hypoxic stress was studied in young Medicago truncatula seedlings. Hypoxic seedlings were characterized by the up-regulation of glutamate dehydrogenase 1 (GDH1) and mitochondrial alanine aminotransferase (mAlaAT), and down-regulation of glutamine synthetase 1b (GS1b), NADH-glutamate synthase (NADH-GOGAT), glutamate dehydrogenase 3 (GDH3), and isocitrate dehydrogenase (ICDH) gene expression. Hypoxic stress severely inhibited GS activity and stimulated NADH-GOGAT activity. GDH activity was lower in hypoxic seedlings than in the control, however, under either normoxia or hypoxia, the in vivo activity was directed towards glutamate deamination. (15)NH(4) labelling showed for the first time that the adaptive reaction of the plant to hypoxia consisted of a concerted modulation of nitrogen flux through the pathways of both alanine and glutamate synthesis. In hypoxic seedlings, newly synthesized (15)N-alanine increased and accumulated as the major amino acid, asparagine synthesis was inhibited, while (15)N-glutamate was synthesized at a similar rate to that in the control. A discrepancy between the up-regulation of GDH1 expression and the down-regulation of GDH activity by hypoxic stress highlighted for the first time the complex regulation of this enzyme by hypoxia. Higher rates of glycolysis and ethanol fermentation are known to cause the fast depletion of sugar stores and carbon stress. It is proposed that the expression of GDH1 was stimulated by hypoxia-induced carbon stress, while the enzyme protein might be involved during post-hypoxic stress contributing to the regeneration of 2-oxoglutarate via the GDH shunt.
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Affiliation(s)
- Anis M Limami
- University of Angers, UMR 1191, Physiologie Moléculaire des Semences, 2 Bd Lavoisier, F-49045, Angers, France.
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Wang C, Zhang HB, Wang LH, Zhang LH. Succinic semialdehyde couples stress response to quorum-sensing signal decay in Agrobacterium tumefaciens. Mol Microbiol 2006; 62:45-56. [PMID: 16942602 DOI: 10.1111/j.1365-2958.2006.05351.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Quorum sensing (QS) signal decay in Agrobacterium tumefaciens occurs in response to starvation or host signals. We have demonstrated that the gamma-aminobutyric acid (GABA) shunt metabolite links stress response to QS signal decay. Mutation of the aldH gene encoding a succinic semialdehyde dehydrogenase (SSADH) that converts succinic semialdehyde (SSA) to succinic acid results in early expression of the signal degrading enzyme, AttM. Exogenous addition of SSA or its precursor GABA induces AttM expression and abolishes Ti plasmid conjugative transfer. SSA acts by binding to the repressor AttJ that regulates the attKLM operon. attK encodes another SSADH. The stress alarmone ppGpp and SSA modulates separately the expression of the two SSADH enzymes, which might control the intracellular SSA level and hence to switch on/off the QS signal decay system in response to environmental changes. These findings document for the first time a sophisticated signalling mechanism of the widely conserved GABA degradation pathway in prokaryotes.
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Affiliation(s)
- Chao Wang
- Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore 138673
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Zhang D, Krishna R, Wang L, Zeng J, Mitroka J, Dai R, Narasimhan N, Reeves RA, Srinivas NR, Klunk LJ. Metabolism, pharmacokinetics, and protein covalent binding of radiolabeled MaxiPost (BMS-204352) in humans. Drug Metab Dispos 2004; 33:83-93. [PMID: 15502007 DOI: 10.1124/dmd.104.001412] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
MaxiPost [(3S)-(+)-(5-chloro-2-methoxyphenyl)-1,3-dihydro-3-fluoro-6-(trifluoromethyl)-2H-indole-2-one); BMS-204352] is an investigational maxi-K channel opener to treat ischemic stroke. This study reports the disposition, metabolism, pharmacokinetics, and protein covalent binding of (14)C-labeled MaxiPost in healthy male volunteers as well as in dogs and rats. After each human subject received a single dose of 10 mg (14)C-labeled BMS-204352 (50 microCi) as a 5-ml intravenous infusion lasting 5 min, the plasma radioactivity concentrations showed a unique profile, wherein the concentration appeared to increase initially, followed by a terminal decline. The mean terminal t(1/2) of plasma radioactivity (259 h) was prolonged compared with that of unchanged parent (37 h). Furthermore, the extractability of radioactivity in plasma decreased over time, reaching approximately 20% at 4 h after dosing. The unextractable radioactivity was covalently bound to plasma proteins through a des-fluoro-des-methyl BMS-204352 lysine adduct. Unchanged BMS-204352 and minor metabolites were identified in plasma extract following protein precipitation. The recovery of the radioactive dose in urine and feces was nearly complete in 14-day collections (approximately 37% in urine and 60% in feces). The N-glucuronide of the parent was the prominent metabolite in urine (16.5% of dose), whereas the parent was a major drug-related component in feces (11% of dose). Similar disposition, metabolism, pharmacokinetic, and protein covalent binding properties of (14)C-labeled BMS-204352 were observed in humans, dogs, and rats.
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Affiliation(s)
- Donglu Zhang
- Pharmaceutical Candidate Optimization, Bristol-Myers Squibb, Route 206 and Province Line Road, Princeton, NJ 08543-4000, USA.
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Abstract
Although alcohol abuse is known to cause a wide array of adverse effects on blood cell formation, the molecular mechanisms by which alcohol exerts its toxic actions have remained poorly defined. Elevated mean corpuscular volume (MCV), macrocytosis, is the most typical morphological abnormality induced by excessive ethanol consumption. This paper reviews recent data indicating that acetaldehyde, the first metabolite of ethanol, may play a role in the haematological derangements in peripheral blood cells and in bone marrow of alcoholic patients. Studies in experimental animals and in human alcoholics have shown that acetaldehyde can bind to proteins and cellular constituents forming stable adducts. Elevated adduct levels have been found from the erythrocytes of alcohol abusers, which may also be associated with ethanol-induced effects in haematopoiesis and adverse consequences in cellular functions.
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Affiliation(s)
- Onni Niemelä
- EP Central Hospital, Laboratory and the Department of Clinical Chemistry, and Institute of Medical Technology, University of Tampere, Finland.
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Metz B, Kersten GFA, Hoogerhout P, Brugghe HF, Timmermans HAM, de Jong A, Meiring H, ten Hove J, Hennink WE, Crommelin DJA, Jiskoot W. Identification of formaldehyde-induced modifications in proteins: reactions with model peptides. J Biol Chem 2003; 279:6235-43. [PMID: 14638685 DOI: 10.1074/jbc.m310752200] [Citation(s) in RCA: 411] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Formaldehyde is a well known cross-linking agent that can inactivate, stabilize, or immobilize proteins. The purpose of this study was to map the chemical modifications occurring on each natural amino acid residue caused by formaldehyde. Therefore, model peptides were treated with excess formaldehyde, and the reaction products were analyzed by liquid chromatography-mass spectrometry. Formaldehyde was shown to react with the amino group of the N-terminal amino acid residue and the side-chains of arginine, cysteine, histidine, and lysine residues. Depending on the peptide sequence, methylol groups, Schiff-bases, and methylene bridges were formed. To study intermolecular cross-linking in more detail, cyanoborohydride or glycine was added to the reaction solution. The use of cyanoborohydride could easily distinguish between peptides containing a Schiff-base or a methylene bridge. Formaldehyde and glycine formed a Schiff-base adduct, which was rapidly attached to primary N-terminal amino groups, arginine and tyrosine residues, and, to a lesser degree, asparagine, glutamine, histidine, and tryptophan residues. Unexpected modifications were found in peptides containing a free N-terminal amino group or an arginine residue. Formaldehyde-glycine adducts reacted with the N terminus by means of two steps: the N terminus formed an imidazolidinone, and then the glycine was attached via a methylene bridge. Two covalent modifications occurred on an arginine-containing peptide: (i) the attachment of one glycine molecule to the arginine residue via two methylene bridges, and (ii) the coupling of two glycine molecules via four methylene bridges. Remarkably, formaldehyde did not generate intermolecular cross-links between two primary amino groups. In conclusion, the use of model peptides enabled us to determine the reactivity of each particular cross-link reaction as a function of the reaction conditions and to identify new reaction products after incubation with formaldehyde.
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Affiliation(s)
- Bernard Metz
- Unit Research and Development, The Netherlands Vaccine Institute, 3720 AL Bilthoven, The Netherlands
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Anni H, Pristatsky P, Israel Y. Binding of Acetaldehyde to a Glutathione Metabolite: Mass Spectrometric Characterization of an Acetaldehyde-Cysteinylglycine Conjugate. Alcohol Clin Exp Res 2003; 27:1613-21. [PMID: 14574232 DOI: 10.1097/01.alc.0000089958.65095.84] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Ethanol administration decreases hepatic glutathione levels and increases urinary sulfhydryl excretion. Ethanol-induced liver injury is blunted by the administration of glutathione precursors. Acetaldehyde generated in the metabolism of ethanol binds to a number of amino acid residues in proteins and peptides, but it does not react readily with glutathione. Due to the possible role of acetaldehyde in cysteine and glutathione homeostasis, we investigated the reaction of acetaldehyde to cysteinylglycine, the dipeptide generated in vivo in the hydrolysis of glutathione by gamma-glutamyltransferase. METHODS A conjugate between acetaldehyde and cysteinylglycine was generated under physiologically relevant conditions, both in vitro and in vivo. It was separated by a new reverse-phase high-performance liquid chromatography method and identified by electrospray ionization/ion trap tandem mass spectrometric analysis. RESULTS The conjugate with a stoichiometry of 1:1 between cysteinylglycine and acetaldehyde is most rapidly generated in vitro and was identified by mass spectroscopy as 2-methyl-thiazolidine-4-carbonyl-glycine. This thiazolidine derivative is stable in vitro and in biological fluids of rats. The conjugate was present in high concentrations in the bile of rats pretreated with ethanol and an inhibitor of aldehyde dehydrogenase. CONCLUSIONS The sequestering of cysteinylglycine by acetaldehyde occurs rapidly under physiologic conditions. Long-lived sulfur-containing biomolecules that incorporate acetaldehyde might affect cysteine and glutathione homeostasis and may also play a protective role by reducing circulating acetaldehyde levels. The acetaldehyde conjugate or its metabolic products could potentially serve as markers of ethanol consumption.
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Affiliation(s)
- Helen Anni
- Department of Pathology-Anatomy and Cell Biology and the Alcohol Research Center, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.
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25
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Zhang D, Ogan M, Gedamke R, Roongta V, Dai R, Zhu M, Rinehart JK, Klunk L, Mitroka J. Protein covalent binding of maxipost through a cytochrome P450-mediated ortho-quinone methide intermediate in rats. Drug Metab Dispos 2003; 31:837-45. [PMID: 12814959 DOI: 10.1124/dmd.31.7.837] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
(3S)-(+)-(5-Chloro-2-methoxyphenyl)-1,3-dihydro-3-fluoro-6-(trifluoromethyl)-2H-indole-2-one) (MaxiPost, BMS-204352) is a potent and specific opener for maxi-K channels and has potential to prevent and treat ischemic stroke. Following single intravenous doses of [14C]BMS-204352 to rats, only 10 to 12% of radioactivity was extractable from plasma with organic solvents. The unextractable radioactivity remained associated with the proteins (mostly albumin) after SDS-polyacrylamide gel electrophoresis or dialysis. Following acid hydrolysis in 6 M HCl for 24 h at 110 degrees C from plasma proteins collected from nine rats dosed with [14C]BMS-204352, one major radioactive product was isolated and identified as a lysine-adduct of des-fluoro des-O-methyl BMS-204352 by liquid chromatography/mass spectrometry and NMR analyses as well as by comparison with the synthetic analog, lysine-adduct of des-fluoro BMS-204352 (BMS-349821). The covalent binding of BMS-204352 results from the displacement of the ring-fluorine atom of des-O-methyl BMS-204352 with the epsilon-amino group of a lysine residue. Microsomal incubations of [14C]BMS-204352 resulted in low levels of covalent binding of radioactivity to proteins. This in vitro covalent binding required cytochrome P450-reductase cofactor NADPH and was attenuated by glutathione. P4503A inhibitors ketoconazole and troleadomycin selectively prevented the covalent binding in vitro. Based on these observations, a two-step bioactivation process for the protein covalent binding of BMS-204352 was postulated: 1) P4503A-mediated O-demethylation leading to spontaneous release of HF and the formation of an ortho-quinone methide reactive metabolite and 2) nucleophilic addition of the epsilon-amino group of protein lysine residue(s) in protein to form des-fluoro des-O-methyl BMS-204352 lysine adduct.
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Affiliation(s)
- Donglu Zhang
- Department of Preclinical Candidate Optimization, P.O. BOX 4000, Bristol-Myers Squibb, Princeton, NJ 08543, USA.
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26
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Ismond KP, Dolferus R, de Pauw M, Dennis ES, Good AG. Enhanced low oxygen survival in Arabidopsis through increased metabolic flux in the fermentative pathway. PLANT PHYSIOLOGY 2003; 132:1292-302. [PMID: 12857811 PMCID: PMC167069 DOI: 10.1104/pp.103.022244] [Citation(s) in RCA: 153] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2003] [Revised: 03/06/2003] [Accepted: 03/21/2003] [Indexed: 05/17/2023]
Abstract
We manipulated the enzyme activity levels of the alcohol fermentation pathway, pyruvate decarboxylase (PDC), and alcohol dehydrogenase (ADH) in Arabidopsis using sense and antisense overexpression of the corresponding genes (PDC1, PDC2, and ADH1). Transgenic plants were analyzed for levels of fermentation and evaluated for changes in hypoxic survival. Overexpression of either Arabidopsis PDC1 or PDC2 resulted in improved plant survival. In contrast, overexpression of Arabidopsis ADH1 had no effect on flooding survival. These results support the role of PDC as the control step in ethanol fermentation. Although ADH1 null mutants had decreased hypoxic survival, attempts to reduce the level of PDC activity enough to see an effect on plant survival met with limited success. The combination of flooding survival data and metabolite analysis allows identification of critical metabolic flux points. This information can be used to design transgenic strategies to improve hypoxic tolerance in plants.
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Affiliation(s)
- Kathleen P Ismond
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada T6G 2E9
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27
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Reichardt P, Schreiber A, Wichmann G, Metzner G, Efer J, Raabe F. Identification and quantification of in vitro adduct formation between protein reactive xenobiotics and a lysine-containing model peptide. ENVIRONMENTAL TOXICOLOGY 2003; 18:29-36. [PMID: 12539141 DOI: 10.1002/tox.10097] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Formation of in vitro adducts between different classes of xenobiotics and the lysine-containing peptide Lys-Tyr was monitored by high-performance liquid chromatography and electrospray ionization mass spectrometry. The molecular structures of the main resulting products could be sensitively analyzed by mass spectrometry (flow injection analysis), enabling the detection of characteristic binding formations. Aldehydes such as formaldehyde, acetaldehyde, and benzaldehyde were shown to form stable linkages to lysine amino groups via Schiff bases. Other electrophilic substances (e.g., toluene-2,4-diisocyanate, 2,4-dinitro-1-fluorobenzene, 2,4,6-trinitrobenzene sulfonic acid, dansyl chloride, and phthalic acid anhydride) also formed covalent adducts with lysine residues. The reactivity of the compounds was quantified by measuring the amount of peptide that remained unchanged after incubation for a certain period with the xenobiotic. Although reactivity levels within this group of aldehydes varied only to a small extent, as would be expected, extreme differences were seen among the structurally heterogeneous group of nonaldehyde xenobiotics. These results support the hypothesis that simple chemical reactions may lead to the adduction of nucleophilic macromolecules such as peptides or proteins. Such reactions, in particular, Schiff base formation of aldehydes, have previously been shown to be capable of specifically interfering with costimulatory signaling on T cells. Our results suggest that electrophilic xenobiotics of other classes may also inherit the capacity to exert similar effects. Forming covalent linkage to peptides may represent a possible molecular mechanism of electrophilic xenobiotics in vivo, yielding immunotoxic effects. The model utilized in this study is appropriate for monitoring the adduction of xenobiotics to basic peptides and for analyzing the resulting molecular structures.
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Affiliation(s)
- Peter Reichardt
- Children's Hospital of the University of Leipzig, Oststrasse 21-25, 04317 Leipzig, Germany
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28
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Flipphi M, Kocialkowska J, Felenbok B. Characteristics of physiological inducers of the ethanol utilization (alc) pathway in Aspergillus nidulans. Biochem J 2002; 364:25-31. [PMID: 11988072 PMCID: PMC1222541 DOI: 10.1042/bj3640025] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The ethanol utilization (alc) pathway in Aspergillus nidulans is one of the strongest expressed gene systems in filamentous fungi. The pathway-specific activator AlcR requires the presence of an inducing compound to activate transcription of genes under its control. We have demonstrated recently that acetaldehyde is the sole physiological inducer of ethanol catabolism. In the present study we show that compounds with catabolism related to that of ethanol, i.e. primary alcohols, primary monoamines and l-threonine, act as inducers because their breakdown results in the production of inducing aliphatic aldehydes. Such aldehydes were shown to induce the alc genes efficiently at low external concentrations. When ethanol is mixed with representatives of another class of strong direct inducers, ketones, the physiological inducer, acetaldehyde, prevails as effector. Although direct inducers essentially carry a carbonyl function, not all aldehydes and ketones act as inducers. Structural features discriminating non-inducing from inducing compounds concern: (i) the length of the aliphatic side group(s); (ii) the presence and nature of any non-aliphatic substituent. These characteristics enable us to predict whether or not a given carbonyl compound will induce the alc genes.
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Affiliation(s)
- Michel Flipphi
- Institut de Génétique et Microbiologie, CNRS UMR 8621, Université Paris-Sud XI, Centre Universitaire d'Orsay, Bâtiment 409, F-91405 Orsay Cedex, France
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29
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Latvala J, Melkko J, Parkkila S, Jarvi K, Makkonen K, Niemela O. Assays for Acetaldehyde-Derived Adducts in Blood Proteins Based on Antibodies Against Acetaldehyde/Lipoprotein Condensates. Alcohol Clin Exp Res 2001. [DOI: 10.1111/j.1530-0277.2001.tb02171.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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30
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Treitz G, Maria G, Giffhorn F, Heinzle E. Kinetic model discrimination via step-by-step experimental and computational procedure in the enzymatic oxidation of D-glucose. J Biotechnol 2001; 85:271-87. [PMID: 11173094 DOI: 10.1016/s0168-1656(00)00371-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The enzymatic oxidation of D-glucose to 2-keto-D-glucose (D-arabino-hexos-2-ulose, D-glucosone) is of prospective industrial interest. Pyranose oxidase (POx) from Peniphora gigantea is deactivated during the reaction. To develop a kinetic model including the main reaction and the enzyme inactivation, possible side-reactions of the non-stabilised enzyme with D-glucosone, hydrogen peroxide, and peroxide radicals were considered. A developed step-by-step combined experimental and computational procedure allowed to discriminate among alternative inactivation mechanisms and provides an increased model reliability. The most probable scheme is the enzyme inactivation by hydroxyl radicals formed from produced H2O2 in the presence of Fe2+ ions. This .OH reaction is supported by matrix assisted laser desorption ionisation-mass spectrometry (MALDI-MS) measurement. The estimated kinetic parameter values for the main reaction are of the same order of magnitude as those reported in the literature. The identified model allows a satisfactory process simulation and highlights measures to prevent the enzyme activity loss.
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Affiliation(s)
- G Treitz
- Technische Biochemie, Universität des Saarlandes, Postfach 151150, Geb. 2, D-66041 Saarbrücken, Germany
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31
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Metzler DE, Metzler CM, Sauke DJ. Chemical Communication Between Cells. Biochemistry 2001. [DOI: 10.1016/b978-012492543-4/50033-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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32
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Jeong KS, Soh Y, Jeng J, Felder MR, Hardwick JP, Song BJ. Cytochrome P450 2E1 (CYP2E1)-dependent production of a 37-kDa acetaldehyde-protein adduct in the rat liver. Arch Biochem Biophys 2000; 384:81-7. [PMID: 11147839 DOI: 10.1006/abbi.2000.2119] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Ethanol-inducible cytochrome P450 2E1 (CYP2E1) has been shown to be involved in the metabolism of both ethanol and acetaldehyde. Acetaldehyde, produced from ethanol metabolism, is highly reactive and can form various protein adducts. In this study, we investigated the role of CYP2E1 in the production of a 37-kDa acetaldehyde-protein adduct. Rats were pairfed an isocaloric control or an alcohol liquid diet with and without cotreatment of YH439, an inhibitor of CYP2E1 gene transcription, for 4 weeks. The soluble proteins from rat livers of each group were separated on SDS-polyacrylamide gels followed by immunoblot analysis using specific antibodies against the 37-kDa protein acetaldehyde adduct. In addition, catalytic activities of the enzymes involved in alcohol and acetaldehyde metabolism were measured and compared with the adduct level. Immunoblot analysis revealed that the 37-kDa adduct, absent in the pair-fed control, was evident in alcohol-fed rats but markedly reduced by YH439 treatment. Immunohistochemical analysis also showed that the 37-kDa adduct is predominantly localized in the pericentral region of the liver where CYP2E1 protein is mainly expressed. This staining disappeared in the pericentral region after YH439 treatment. The levels of alcohol dehydrogenase (ADH) and aldehyde dehydrogenase isozymes were unchanged after YH439 treatment. However, the level of the 37-kDa protein adduct positively correlated with the hepatic content of P4502E1. These data indicate that the 37-kDa adduct could be produced by CYP2E1-mediated ethanol metabolism in addition to the ADH-dependent formation.
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Affiliation(s)
- K S Jeong
- Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, Rockville, Maryland 20852, USA
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33
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34
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Peterson KP, Pavlovich JG, Goldstein D, Little R, England J, Peterson CM. What is hemoglobin A1c? An analysis of glycated hemoglobins by electrospray ionization mass spectrometry. Clin Chem 1998. [DOI: 10.1093/clinchem/44.9.1951] [Citation(s) in RCA: 135] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AbstractHemoglobin A1c (HbA1c) is a stable minor Hb variant formed in vivo by posttranslational modification by glucose, originally identified by using cation exchange chromatography, and containing primarily glycated N-terminal β-chains. However, the structure(s) of the quantified species has not been elucidated, and the available methods lack a reference standard. We used electrospray ionization mass spectrometry to determine the extent of glycation of samples separated by boronate affinity and/or cation exchange chromatography. Analyses of clinical samples were consistent with the curvilinear relationship of patient glucose and HbA1c. As glycation increased, the ratio of β-chain to α-chain glycation increased, and the number of glycation sites on the β-chain increased, although these were relatively minor components. We found several glycated species that cochromatographed with HbA1c on cation exchange, including species with both glycated α- and β-chains, nonglycated α- and glycated β-chains, and multiply glycated β-chains. The combined use of affinity and cation exchange chromatography with structural confirmation by electrospray ionization mass spectrometry was found to be useful in producing samples of sufficient purity for the standardization of glycohemoglobin clinical assays.
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Affiliation(s)
| | - James G Pavlovich
- Chemistry Department, University of California, Santa Barbara, CA 93106
| | - David Goldstein
- School of Medicine, University of Missouri, Columbia, MO 65212
| | - Randie Little
- School of Medicine, University of Missouri, Columbia, MO 65212
| | - Jack England
- School of Medicine, University of Missouri, Columbia, MO 65212
| | - Charles M Peterson
- Sansum Medical Research Foundation, Santa Barbara, CA 93111
- National Heart, Lung, and Blood Institute/National Institutes of Health, Division of Blood Diseases and Resources, 6701 Rockledge Dr., 10th floor, Room 10158, Bethesda, MD 20817
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35
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Braun KP, Pavlovich JG, Jones DR, Peterson CM. Stable acetaldehyde adducts: structural characterization of acetaldehyde adducts of human hemoglobin N-terminal beta-globin chain peptides. Alcohol Clin Exp Res 1997; 21:40-3. [PMID: 9046371 DOI: 10.1111/j.1530-0277.1997.tb03726.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Acetaldehyde is the first oxidation product of ethanol in vivo. Our earlier work showed that with sufficient acetaldehyde, five of the six possible sites of the peptide pentalysine were modified as a Schiff base (Braun KP, et al: J Biol Chem 270:11263-11266, 1995). However, we were unable to deduce unequivocally which site was unmodified. Lysine residues, as well as the amine terminal valine residues, in hemoglobin have been implicated as target structures for acetaldehyde adducts resulting from ethanol consumption. Hemoglobin adducts of acetaldehyde have been used clinically as a marker of ethanol consumption, but the chemical nature of these adducts remains undefined. As part of our continuing structural characterization of acetaldehyde-protein adduct formation, we studied the peptides Val-His-Leu-Thr-Pro and Val-His-Leu-Thr-Pro-Val-Glu-Lys, from the amine terminus of the beta-globin chain of hemoglobin, in vitro. Both peptides have at least one potential site for adduct formation. In the octapeptide, the N-terminal amine group of Val as well as the epsilon-amine group of the lysine sidechain can potentially be modified by acetaldehyde. We used mass spectrometry, carbon-13 nuclear magnetic resonance, and Raman spectroscopy and characterized stable Schiff base acetaldehyde adducts of these two peptides at both reactive sites. The identification of stable Schiff base adducts with the N-terminal peptides of the beta-chain of hemoglobin as well as with epsilon-amino groups of lysine provides another possible means of monitoring ethanol consumption. The functional implications of these stable Schiff bases remains undefined.
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Affiliation(s)
- K P Braun
- Sansum Medical Research Foundation, Santa Barbara, CA 93105, USA
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36
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Bailey AL, Wortley G, Southon S. Measurement of aldehydes in low density lipoprotein by high performance liquid chromatography. Free Radic Biol Med 1997; 23:1078-85. [PMID: 9358252 DOI: 10.1016/s0891-5849(97)00162-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A modified procedure is presented for the HPLC determination of nanomolar concentrations of n-alkanals, hydroxyalkenals, malondialdehyde and furfural in biological fluid. The modifications allow aldehyde profile analysis of small samples of fresh, human, low density lipoprotein (LDL), enabling more detailed studies of LDL fatty acid peroxidation. Aldehydes are reacted with 1,3-cyclohexanedione to produce fluorescent derivatives which are separated by gradient, reversed phase, high performance liquid chromatography (HPLC). Analysis time has been reduced by shortening the sample preparation. Sensitivity has been increased by miniaturization of the derivatisation procedure, reducing required sample size. Recoveries of added aldehydes have been improved. In addition, the method presented allows determination of three further aldehydes, not measured previously by CHD methods: malondialdehyde, formaldehyde and furfural. Recovery and variability data and concentrations of aldehydes found in human LDL are given. The capacity of the method for further development, to enable determination of other aldehydes such as the trans, 2-alkenals, is also demonstrated.
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Affiliation(s)
- A L Bailey
- Nutrition, Diet and Health Department, Institute of Food Research, UK
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37
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Song BJ. Ethanol-inducible cytochrome P450 (CYP2E1): biochemistry, molecular biology and clinical relevance: 1996 update. Alcohol Clin Exp Res 1996; 20:138A-146A. [PMID: 8947253 DOI: 10.1111/j.1530-0277.1996.tb01764.x] [Citation(s) in RCA: 119] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- B J Song
- Laboratory of Neurogenetics, National Institute on Alcohol Abuse and Alcoholism, Rockville, MD, USA
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