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Zhang Y, Li Z, Zhang Y, Sun K, Ren N, Li M. Acute toxic effects of diclofenac exposure on freshwater crayfish (Procambarus clarkii): Insights from hepatopancreatic pathology, molecular regulation and intestinal microbiota. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 244:114068. [PMID: 36108435 DOI: 10.1016/j.ecoenv.2022.114068] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 08/27/2022] [Accepted: 09/06/2022] [Indexed: 06/15/2023]
Abstract
In this study, we exposed adult male crayfish (Procambarus clarkii) to different concentrations of diclofenac (DCF) for 96 h. In the meantime, we investigated the alternations of hepatopancreatic pathology, molecular regulation and intestinal microbiota of P. clarkii exposed to DCF. The results demonstrated DCF led to histological changes including epithelium vacuolization and tubule lumen dilatation in the hepatopancreas. Transcriptome sequencing analysis showed that 642 and 586 genes were differentially expressed in the hepatopancreas of P. clarkii exposed to 1 and 10 mg/L DCF, respectively. DCF could affect the functions of antioxidation, immunity and metabolism of hepatopancreas by inducing the abnormal expressions of immune- and redox-related genes. GO enrichment results demonstrated that 10 mg/L DCF exposure could modulate the processes of molting, amino sugar metabolism, protein hydrolysis and intracellular protein translocation of P. clarkii. Additionally, the abundances of bacterial families including Shewanellaceae, Bacteroidaceae, Vibrionaceae, Erysipelotrichaceae, Aeromonadaceae, Moraxellaceae, etc. in the intestine were significantly changed after DCF exposure, and the disruption of intestinal flora might further cause abnormal intestinal metabolism in P. clarkii. This study provides novel mechanistic insights into the toxic effects of anti-inflammatory drugs on aquatic crustaceans.
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Affiliation(s)
- Yu Zhang
- Key Laboratory of Soil Resource Sustainable Utilization for Jilin Province Commodity Grain Bases, College of Resources and Environment, Jilin Agricultural University, Changchun 130118, China
| | - Zheyu Li
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Yanxiang Zhang
- School of Environmental and Material Engineering, Yantai University, Yantai 264005, China
| | - Kai Sun
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China.
| | - Nanqi Ren
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Mingtang Li
- Key Laboratory of Soil Resource Sustainable Utilization for Jilin Province Commodity Grain Bases, College of Resources and Environment, Jilin Agricultural University, Changchun 130118, China
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2
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Lahham M, Jha S, Goj D, Macheroux P, Wallner S. The family of sarcosine oxidases: Same reaction, different products. Arch Biochem Biophys 2021; 704:108868. [PMID: 33812916 DOI: 10.1016/j.abb.2021.108868] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 03/26/2021] [Accepted: 03/27/2021] [Indexed: 12/11/2022]
Abstract
The subfamily of sarcosine oxidase is a set of enzymes within the larger family of amine oxidases. It is ubiquitously distributed among different kingdoms of life. The member enzymes catalyze the oxidization of an N-methyl amine bond of amino acids to yield unstable imine species that undergo subsequent spontaneous non-enzymatic reactions, forming an array of different products. These products range from demethylated simple species to complex alkaloids. The enzymes belonging to the sarcosine oxidase family, namely, monomeric and heterotetrameric sarcosine oxidase, l-pipecolate oxidase, N-methyltryptophan oxidase, NikD, l-proline dehydrogenase, FsqB, fructosamine oxidase and saccharopine oxidase have unique features differentiating them from other amine oxidases. This review highlights the key attributes of the sarcosine oxidase family enzymes, in terms of their substrate binding motif, type of oxidation reaction mediated and FAD regeneration, to define the boundaries of this group and demarcate these enzymes from other amine oxidase families.
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Affiliation(s)
- Majd Lahham
- Institute of Biochemistry, Graz University of Technology, NAWI Graz, Graz, Austria; Department of Biochemistry and Microbiology, Aljazeera Private University, Ghabagheb, Syria
| | - Shalinee Jha
- Institute of Biochemistry, Graz University of Technology, NAWI Graz, Graz, Austria
| | - Dominic Goj
- Institute of Biochemistry, Graz University of Technology, NAWI Graz, Graz, Austria
| | - Peter Macheroux
- Institute of Biochemistry, Graz University of Technology, NAWI Graz, Graz, Austria
| | - Silvia Wallner
- Institute of Biochemistry, Graz University of Technology, NAWI Graz, Graz, Austria.
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3
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Doubayashi D, Oki M, Mikami B, Uchida H. The microenvironment surrounding FAD mediates its conversion to 8-formyl-FAD in Aspergillus oryzae RIB40 formate oxidase. J Biochem 2019; 166:67-75. [PMID: 30715389 DOI: 10.1093/jb/mvz009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 01/29/2019] [Indexed: 11/15/2022] Open
Abstract
Aspergillus oryzae RIB40 formate oxidase has Arg87 and Arg554 near the formyl group and O(4) atom of 8-formyl-flavin adenine dinucleotide (FAD), respectively, with Asp396 neighbouring Arg554. Herein, we probed the roles of these three residues in modification of FAD to 8-formyl-FAD. Replacement of Arg87 or Arg554 with Lys or Ala decreased and abolished the modification, respectively. Replacement of Asp396 with Ala or Asn lowered the modification rate. The observation of unusual effects of maintaining pH 7.0 on the modification in R87K, R554K and D396 variants indicates initial and subsequent processes with different pH dependencies. Comparison of the initial process at pH 4.5 and 7.0 suggests that the microenvironment around Arg87 and the protonation state of Asp396 affect the initial process in the native enzyme. Comparison of the crystal structures of native and R554 variants showed that the replacements had minimal effect on catalytic site structure. The positively charged Arg87 might contribute to the formation of an anionic quinone-methide tautomer intermediate, while the positively charged Arg554, in collaboration with the negatively charged Asp396, might stabilize this intermediate and form a hydrogen bonding network with the N(5)/O(4) region, thereby facilitating efficient FAD modification.
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Affiliation(s)
- Daiju Doubayashi
- Department of Applied Chemistry and Biotechnology, Graduate School of Engineering, University of Fukui, Fukuishi, Japan
| | - Masaya Oki
- Department of Applied Chemistry and Biotechnology, Graduate School of Engineering, University of Fukui, Fukuishi, Japan
| | - Bunzo Mikami
- Division of Agronomy and Horticultural Science, Graduate School of Agriculture, Kyoto University, Ujishi, Japan
| | - Hiroyuki Uchida
- Department of Applied Chemistry and Biotechnology, Graduate School of Engineering, University of Fukui, Fukuishi, Japan
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Sharma P, Maklashina E, Cecchini G, Iverson TM. Maturation of the respiratory complex II flavoprotein. Curr Opin Struct Biol 2019; 59:38-46. [PMID: 30851631 DOI: 10.1016/j.sbi.2019.01.027] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 01/31/2019] [Indexed: 12/13/2022]
Abstract
Respiratory complexes are complicated multi-subunit cofactor-containing machines that allow cells to harvest energy from the environment. Maturation of these complexes requires protein folding, cofactor insertion, and assembly of multiple subunits into a final, functional complex. Because the intermediate states in complex maturation are transitory, these processes are poorly understood. This review gives an overview of the process of maturation in respiratory complex II with a focus on recent structural studies on intermediates formed during covalent flavinylation of the catalytic subunit, SDHA. Covalent flavinylation has an evolutionary significance because variants of complex II enzymes with the covalent ligand removed by mutagenesis cannot oxidize succinate, but can still perform the reverse reaction and reduce fumarate. Since succinate oxidation is a key step of aerobic respiration, the covalent bond of complex II appears to be important for aerobic life.
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Affiliation(s)
- Pankaj Sharma
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, United States
| | - Elena Maklashina
- Molecular Biology Division, San Francisco VA Health Care System, San Francisco, CA 94121, United States; Department of Biochemistry & Biophysics, University of California, San Francisco, CA 94158, United States
| | - Gary Cecchini
- Molecular Biology Division, San Francisco VA Health Care System, San Francisco, CA 94121, United States; Department of Biochemistry & Biophysics, University of California, San Francisco, CA 94158, United States.
| | - T M Iverson
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, United States; Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, United States; Center for Structural Biology, Vanderbilt University, Nashville, TN 37232, United States; Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN 37232, United States.
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5
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An electrochemical sarcosine sensor based on biomimetic recognition. Mikrochim Acta 2019; 186:136. [PMID: 30707309 DOI: 10.1007/s00604-019-3240-0] [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: 10/20/2018] [Accepted: 01/05/2019] [Indexed: 01/13/2023]
Abstract
A nonenzymatic electrochemical sensor is described for the prostate cancer biomarker sarcosine (Sar). Riboflavin was employed to mimic the active center of the enzyme sarcosine oxidase for constructing the biomimetic sensor. The use of riboflavon (Rf) avoids the disadvantages of an enzymatic sensor, such as high cost and poor stability. A glassy carbon electrode (GCE) was modified with a graphene-chitosan (GR) composite and further modified with gold-platinum bimetallic nanoparticles in a polypyrrole (PPy) matrix in order to enhance the catalytic activity of the enzyme mimic. Finally, Rf was electrodeposited on the surface of the AuPt-PPy/GR-modified GCE. Under optimized conditions, the GCE provided high sensitivity and selectivity for Sar at around 0.61 V. Response covers the 2.5-600 μM concentration range, and the detection limit is 0.68 μM. The method was successfully applied to the determination of Sar in spiked urine with 98.0%-103.2% recovery. Graphical abstract Schematic presentation of the fabrication of the Rf/AuPt-PPy/GR/GCE surface and the measurement principle by differential pulse voltammetry (DPV).
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Soluble expression of Thermomicrobium roseum sarcosine oxidase and characterization of N-demethylation activity. MOLECULAR CATALYSIS 2019. [DOI: 10.1016/j.mcat.2018.12.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Preparation, reconstruction, and characterization of a predicted Thermomicrobium roseum sarcosine oxidase. MOLECULAR CATALYSIS 2018. [DOI: 10.1016/j.mcat.2018.06.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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X-ray structures of fructosyl peptide oxidases revealing residues responsible for gating oxygen access in the oxidative half reaction. Sci Rep 2017; 7:2790. [PMID: 28584265 PMCID: PMC5459902 DOI: 10.1038/s41598-017-02657-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 04/18/2017] [Indexed: 01/07/2023] Open
Abstract
Current enzymatic systems for quantifying glycated hemoglobin are based on the FAD-containing enzyme fructosyl peptide oxidase (FPOX). FPOX has substrate specificity for fructosyl-α N-valyl-histidine derived from proteolytic digestion of the N-terminus of the HbA1c β-chain. This study reports the X-ray structures of the wild-type and Asn56Ala (N56A) mutant of Phaeosphaeria nodorum fructosyl peptide oxidase (PnFPOX) to elucidate the residues responsible for the oxidative half-reaction. N56A showed decreased oxidase activity compared to the wild -type, while its dye-mediated dehydrogenase activity was higher than that of wild type. In wild-type PnFPOX, Asn56 forms a hydrogen bond with Lys274, thereby preventing it from forming a salt bridge with Asp54. By contrast, Lys274 of PnFPOX N56A moves toward Asp54, and they approach each other to form a salt bridge at a distance of 2.92-3.35 Å. Site-directed mutagenesis studies and protein channel analysis suggest that Asp54 assists in accepting oxygen properly at the position of the bound water molecule in the main oxygen channel. These results reveal that Asn56 in PnFPOX is essential for maintaining an effective oxygen accession path, and support the role of Asp54 as a gate keeper that cooperates with Lys274 to enable oxygen to reach the active site properly.
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Jhulki I, Chanani PK, Abdelwahed SH, Begley TP. A Remarkable Oxidative Cascade That Replaces the Riboflavin C8 Methyl with an Amino Group during Roseoflavin Biosynthesis. J Am Chem Soc 2016; 138:8324-7. [PMID: 27331868 PMCID: PMC5610575 DOI: 10.1021/jacs.6b02469] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Roseoflavin is a naturally occurring riboflavin analogue with antibiotic properties. It is biosynthesized from riboflavin in a reaction involving replacement of the C8 methyl with a dimethylamino group. Herein we report the identification of a flavin-dependent enzyme that converts flavin mononucleotide (FMN) and glutamate to 8-amino-FMN via the intermediacy of 8-formyl-FMN. A mechanistic proposal for this remarkable transformation is proposed.
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Affiliation(s)
- Isita Jhulki
- Department of Chemistry, Texas A&M University, 3255 TAMU, College Station, Texas 77843, United States
| | - Prem K. Chanani
- Department of Chemistry, Texas A&M University, 3255 TAMU, College Station, Texas 77843, United States
| | - Sameh H. Abdelwahed
- Department of Chemistry, Texas A&M University, 3255 TAMU, College Station, Texas 77843, United States
| | - Tadhg P. Begley
- Department of Chemistry, Texas A&M University, 3255 TAMU, College Station, Texas 77843, United States
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Enhancement of soluble expression of codon-optimized Thermomicrobium roseum sarcosine oxidase in Escherichia coli via chaperone co-expression. J Biotechnol 2015; 218:75-84. [PMID: 26626227 DOI: 10.1016/j.jbiotec.2015.11.018] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Revised: 11/18/2015] [Accepted: 11/23/2015] [Indexed: 12/30/2022]
Abstract
The codon-optimized sarcosine oxidase from Thermomicrobium roseum (TrSOX) was successfully expressed in Escherichia coli and its soluble expression was significantly enhanced via the co-expression of chaperones. With the assistance of whole-genome analysis of T. roseum DSM 5159, the sox gene was predicated and its sequence was optimized based on the codon bias of E. coli. The TrSOX gene was successfully constructed in the pET28a plasmid. After induction with IPTG for 8h, SDS-PAGE analysis of crude enzyme solutions showed a significant 43 kDa protein band, indicating SOX was successfully expressed in E. coli. However, the dark band corresponding to the intracellular insoluble fraction indicated that most of TrSOX enzyme existed in the inactive form in "inclusion bodies" owing to the "hot spots" of TrSOX. Furthermore, the co-expression of five different combinations of chaperones indicated that the soluble expression of TrSOX was greatly improved by the co-expression of molecular chaperones GroES-GroEL and DnaK-DnaJ-GrpE-GroES-GroEL. Additionally, the analysis of intramolecular forces indicated that the hydrophobic amino acids, hydrogen bonds, and ionic bonds were favorable for enhancing the interaction and stability of TrSOX secondary structure. This study provides a novel strategy for enhancing the soluble expression of TrSOX in E. coli.
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11
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Bucci A, Abrams CF. Oxygen Pathways and Allostery in Monomeric Sarcosine Oxidase via Single-Sweep Free-Energy Reconstruction. J Chem Theory Comput 2014; 10:2668-2676. [PMID: 25061440 PMCID: PMC4095932 DOI: 10.1021/ct500088z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Indexed: 01/12/2023]
Abstract
Monomeric sarcosine oxidase (MSOX) is a flavoprotein D-amino acid oxidase with reported sarcosine and oxygen activation sites on the re and si faces of the flavin ring, respectively. O2 transport routes to the catalytic interior are not well understood and are difficult to ascertain solely from MSOX crystal structures. A composite free-energy method known as single-sweep is used to map and thermodynamically characterize oxygen sites and routes leading to the catalytically active Lys265 from the protein surface. The result is a network of pathways and free energies within MSOX illustrating that oxygen can access two free-energy minima on the re face of the reduced flavin from four separate solvent portals. No such minimum is observed on the si face. The pathways are geometrically similar for three major states of the enzyme: (1) apo with a closed flavin cleft, (2) apo with an open flavin cleft, and (3) inhibitor-bound with a closed flavin cleft. Interestingly, free energies along these transport pathways display significantly deeper minima when the substrate-mimicking inhibitor 2-furoic acid is bound at the sarcosine site, even at locations far from this site. This suggests a substrate-dependent allosteric modulation of the kinetics of O2 transport from the solvent to the active site.
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Affiliation(s)
- Anthony Bucci
- Dept. Chemical and Biological
Engineering, Drexel University, Philadelphia, Pennsylvania 19104, United States
| | - Cameron F. Abrams
- Dept. Chemical and Biological
Engineering, Drexel University, Philadelphia, Pennsylvania 19104, United States
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12
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Zhou Y, Yin H, Meng X, Xu Z, Fu Y, Ai S. Direct electrochemistry of sarcosine oxidase on graphene, chitosan and silver nanoparticles modified glassy carbon electrode and its biosensing for hydrogen peroxide. Electrochim Acta 2012. [DOI: 10.1016/j.electacta.2012.04.014] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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13
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Collard F, Fagan RL, Zhang J, Palfey BA, Monnier VM. The cation-π interaction between Lys53 and the flavin of fructosamine oxidase (FAOX-II) is critical for activity. Biochemistry 2011; 50:7977-86. [PMID: 21755947 PMCID: PMC3557951 DOI: 10.1021/bi1020666] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Fructosamine oxidases (FAOXs) are flavin-containing enzymes that catalyze the oxidative deglycation of low molecular weight fructosamines or Amadori products. The fructosamine substrate is oxidized by the flavin in the reductive half-reaction, and the reduced flavin is then oxidized by molecular oxygen in the oxidative half-reaction. The crystal structure of FAOX-II from Aspergillus fumigatus reveals a unique interaction between Lys53 and the isoalloxazine. The ammonium nitrogen of the lysine is in contact with and nearly centered over the aromatic ring of the flavin on the si-face. Here, we investigate the importance of this unique interaction on the reactions catalyzed by FAOX by studying both half-reactions of the wild-type and Lys53 mutant enzymes. The positive charge of Lys53 is critical for flavin reduction but plays very little role in the reaction with molecular oxygen. The conservative mutation of Lys53 to arginine had minor effects on catalysis. However, removing the charge by replacing Lys53 with methionine caused more than a million-fold decrease in flavin reduction, while only slowing the oxygen reaction by ∼30-fold.
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Affiliation(s)
- François Collard
- Department of Pathology and Biochemistry, Case Western Reserve University, Cleveland, OH, 44106-7288
| | | | - Jianye Zhang
- Department of Pathology and Biochemistry, Case Western Reserve University, Cleveland, OH, 44106-7288
| | - Bruce A. Palfey
- Department of Biological Chemistry, University of Michigan Medical School, 1150 W. Medical Center Dr., Ann Arbor, MI 48109-0606
| | - Vincent M. Monnier
- Department of Pathology and Biochemistry, Case Western Reserve University, Cleveland, OH, 44106-7288
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Zhao G, Bruckner RC, Jorns MS. Identification of the oxygen activation site in monomeric sarcosine oxidase: role of Lys265 in catalysis. Biochemistry 2008; 47:9124-35. [PMID: 18693755 PMCID: PMC2764408 DOI: 10.1021/bi8008642] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Monomeric sarcosine oxidase (MSOX) catalyzes the oxidation of N-methylglycine and contains covalently bound FAD that is hydrogen bonded at position N(5) to Lys265 via a bridging water. Lys265 is absent in the homologous but oxygen-unreactive FAD site in heterotetrameric sarcosine oxidase. Isolated preparations of Lys265 mutants contain little or no flavin but can be covalently reconstituted with FAD. Mutation of Lys265 to a neutral residue (Ala, Gln, Met) causes a 6000- to 9000-fold decrease in apparent turnover rate whereas a 170-fold decrease is found with Lys265Arg. Substitution of Lys265 with Met or Arg causes only a modest decrease in the rate of sarcosine oxidation (9.0- or 3.8-fold, respectively), as judged by reductive half-reaction studies which show that the reactions proceed via an initial enzyme.sarcosine charge transfer complex and a novel spectral intermediate not detected with wild-type MSOX. Oxidation of reduced wild-type MSOX (k = 2.83 x 10(5) M(-1) s(-1)) is more than 1000-fold faster than observed for the reaction of oxygen with free reduced flavin. Mutation of Lys265 to a neutral residue causes a dramatic 8000-fold decrease in oxygen reactivity whereas a 250-fold decrease is observed with Lys265Arg. The results provide definitive evidence for Lys265 as the site of oxygen activation and show that a single positively charged amino acid residue is entirely responsible for the rate acceleration observed with wild-type enzyme. Significantly, the active sites for sarcosine oxidation and oxygen reduction are located on opposite faces of the flavin ring.
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Affiliation(s)
- Guohua Zhao
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, Pennsylvania 19102, USA
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