A5010176095- Enzyme-mediated dye degradation
- Photosynthetic Processes and Mechanisms
- Carbohydrate Chemistry and Synthesis
- Amino Acid Enzymes and Metabolism
- Metal-Catalyzed Oxygenation Mechanisms
- Redox biology and oxidative stress
- Microbial bioremediation and biosurfactants
- Microbial Metabolic Engineering and Bioproduction
- Polyamine Metabolism and Applications
- Electrochemical Analysis and Applications
- Microbial metabolism and enzyme function
- Nitric Oxide and Endothelin Effects
- Electrochemical sensors and biosensors
- Biotin and Related Studies
- Biochemical and biochemical processes
- Biofuel production and bioconversion
- Studies on Chitinases and Chitosanases
- Enzyme Production and Characterization
- Catalysis for Biomass Conversion
- Photochemistry and Electron Transfer Studies
Chulalongkorn University
2008-2023
King Mongkut's University of Technology North Bangkok
2019
Mahidol University
2006-2013
p-Hydroxyphenylacetate hydroxylase from Acinetobacter baumannii is a two-component system consisting of NADH-dependent FMN reductase and monooxygenase (C2) that uses reduced as substrate. The crystal structures C2 in the ligand-free substrate-bound forms reveal preorganized pocket binds without large conformational changes. Phe-266 side chain swings out to provide space for binding p-hydroxyphenylacetate oriented orthogonal flavin ring. geometry substrate-binding site significantly different...
This work describes for the first time identification of a reaction intermediate, C4a-hydroperoxyflavin, during oxidative half-reaction flavoprotein oxidase, pyranose 2-oxidase (P2O) from Trametes multicolor, by using rapid kinetics. The reduced P2O reacted with oxygen forward rate constant 5.8 × 104 M−1 s−1 and reverse 2 s−1, resulting in formation C4a-hydroperoxyflavin intermediate which decayed 18 s−1. absorption spectrum resembled spectra flavin-dependent monooxygenases. A hydrophobic...
Pyranose 2-oxidase (P2Ox) participates in fungal lignin degradation by producing the H2O2 needed for lignin-degrading peroxidases. The enzyme oxidizes cellulose- and hemicellulose-derived aldopyranoses at C2 preferentially, but also on C3, to corresponding ketoaldoses. To investigate structural determinants of catalysis, covalent flavinylation, substrate binding, regioselectivity, wild-type mutant P2Ox enzymes were produced characterized biochemically structurally. Removal histidyl-FAD...
Pyranose 2-oxidase (P2O) 5The abbreviations used are: P2Opyranose 2-oxidaseABTS2,2′-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) diammonium saltλwavelengthWTwild typeMes4-morpholineethanesulfonic acid. catalyzes the oxidation by O2 of d-glucose and several aldopyranoses to yield 2-ketoaldoses H2O2. Based on crystal structures, in one rotamer conformation, threonine hydroxyl Thr169 forms H-bonds flavin-N5/O4 locus, whereas, a different rotamer, it may interact with either sugar or other...
Pyranose 2-oxidase (P2O) from Trametes multicolor is a flavoprotein oxidase that catalyzes the oxidation of aldopyranoses by molecular oxygen to yield corresponding 2-keto-aldoses and hydrogen peroxide. P2O first enzyme in class oxidases, for which C4a-hydroperoxy-flavin adenine dinucleotide (FAD) intermediate has been detected during oxidative half-reaction. In this study, reduction kinetics d-glucose 2-d-d-glucose at pH 7.0 was investigated using stopped-flow techniques. The results...
The flavin-based electron bifurcation (FBEB) system from Acidaminococcus fermentans is composed of the transfer flavoprotein (EtfAB) and butyryl-CoA dehydrogenase (Bcd). α-FAD binds to domain II A-subunit EtfAB, β-FAD B-subunit EtfAB δ-FAD Bcd. NADH reduces β-FADH- , which bifurcates one high potential α-FAD•- semiquinone followed by other low ferredoxin (Fd). As deduced crystal structures, upon interaction with Bcd, formed α-FADH- approaches rotation II, yielding δ-FAD•- . Repetition this...
Vibrio spp. play a crucial role in the global recycling of highly abundant recalcitrant biopolymer chitin marine ecosystems through their ability to secrete chitin-degrading enzymes efficiently hydrolyse chitinous materials and use them as major carbon source. In this study, first crystal structures complete four-domain chitin-active AA10 lytic polysaccharide monooxygenase from chitinolytic bacterium campbellii type strain ATCC BAA-1116 are reported. The apo copper-bound Vh LPMO10A were...
Pyranose 2-oxidase (P2O) from Trametes multicolor is a flavoenzyme that catalyzes the oxidation of d-glucose and other aldopyranose sugars at C2 position by using O2 as an electron acceptor to form corresponding 2-keto-sugars H2O2. In this study, effects pH on oxidative half-reaction P2O were investigated stopped-flow spectrophotometry. The results showed flavin occurred via different pathways depending environment. At values lower than 8.0, reduced reacts with C4a-hydroperoxyflavin...
Ionic liquid (IL) pretreatment is an efficient method to improve the enzymatic hydrolysis. The limitation of using IL its high cost, thus there a need for improvement make it feasible industrial applications. In this research, IL, 1-ethyl-3-methyl-acetate (Emim-AC), rice straw was conducted by mixing with inorganic salts reduce load in reaction, i.e. cost process. aqueous mixtures Emim-AC and 6 types salts, including NaCl, KCl, MgCl2, NaNO3, KNO3 Mg(NO3)2 were individually prepared tested at...