A5048016830- Enzyme-mediated dye degradation
- Biochemical and biochemical processes
- Biofuel production and bioconversion
- Lignin and Wood Chemistry
- Microbial Fuel Cells and Bioremediation
- Electrochemical sensors and biosensors
- Advanced Cellulose Research Studies
- Microbial Metabolism and Applications
- Electrochemical Analysis and Applications
- Chromium effects and bioremediation
- Polysaccharides and Plant Cell Walls
- Fungal Biology and Applications
- Analytical chemistry methods development
- Metal Extraction and Bioleaching
- Metal-Catalyzed Oxygenation Mechanisms
- Radioactive element chemistry and processing
- Forest Insect Ecology and Management
- Microbial bioremediation and biosurfactants
- Pesticide and Herbicide Environmental Studies
- Photosynthetic Processes and Mechanisms
- Environmental Toxicology and Ecotoxicology
- Insect symbiosis and bacterial influences
- Enzyme Production and Characterization
- Geochemistry and Elemental Analysis
- Microbial Community Ecology and Physiology
Pennsylvania State University
2015-2024
Intel (Taiwan)
2022
Institute of Cytochemistry and Molecular Pharmacology
2009
National Institutes of Health
1999-2004
National Heart Lung and Blood Institute
1999-2004
University of Florence
1991-1999
Utah State University
1997
University of Wisconsin–Madison
1985-1996
United States Department of Agriculture
1984-1993
Luye Pharma (China)
1991
An extracellular lignin-degrading enzyme from the basidiomycete Phanerochaete chrysosporium Burdsall was purified to homogeneity by ion-exchange chromatography. The 42,000-dalton ligninase contains one protoheme IX per molecule. It catalyzes, nonstereospecifically, several oxidations in alkyl side chains of lignin-related compounds: C α —C β cleavage compounds type aryl—C HOH—C HR—C γ H 2 OH (R = -aryl or - O -aryl), oxidation benzyl alcohols aldehydes ketones, intradiol phenylglycol...
The extracellular fluid of ligninolytic cultures the wood-decomposing basidiomycete Phanerochaete chrysosporium Burds. contains an enzyme that degrades lignin substructure model compounds as well spruce and birch lignins. It has a molecular size 42,000 daltons requires hydrogen peroxide for activity.
The white rot fungus Phanerochaete chrysosporium degraded DDT [1,1,-bis(4-chlorophenyl)-2,2,2-trichloroethane], 3,4,3',4'-tetrachlorobiphenyl, 2,4,5,2',-4',5'-hexachlorobiphenyl, 2,3,7,8-tetrachlorodibenzo-p-dioxin, lindane (1,2,3,4,5,6-hexachlorocylohexane), and benzo[a]pyrene to carbon dioxide. Model studies, based on the use of DDT, suggest that ability metabolize these compounds is dependent extracellular lignin-degrading enzyme system this fungus.
A number of species Gram-negative bacteria can use insoluble minerals Fe(III) and Mn(IV) as extracellular respiratory electron acceptors. In some Shewanella, deca-heme transfer proteins lie at the face outer membrane (OM), where they interact with substrates. To reduce substrates, these redox must be charged by inner membrane/periplasmic system. Here, we present a spectro-potentiometric characterization trans-OM icosa-heme complex, MtrCAB, demonstrate its capacity to move electrons across...
The aromatic polymer lignin protects plants from most forms of microbial attack. Despite the fact that a significant fraction all lignocellulose degraded passes through arthropod guts, fate in these systems is not known. Using tetramethylammonium hydroxide thermochemolysis, we show degradation by two insect species, Asian longhorned beetle ( Anoplophora glabripennis ) and Pacific dampwood termite Zootermopsis angusticollis ). In both termite, levels propyl side-chain oxidation...
The hemoprotein ligninase of Phanerochaete chrysosporium catalyzes, in the presence H2O2, a variety seemingly different oxidations lignin and model compounds. Here we show that enzyme also catalyzes oxidation various methoxybenzenes. ESR spectroscopy shows compounds are oxidized to aryl cation radicals. These decompose, evidently by H2O addition. Thus, 1,4-dimethoxybenzene is converted p-benzoquinone methanol. We propose unified mechanism, based on formation radicals, explain reactions...
The lignin peroxidases (LiPs) of white-rot basidiomycetes are generally thought to catalyze the oxidative cleavage polymeric in vivo. However, direct evidence for such a role has been lacking. In this investigation, 14C- and 13C-labeled synthetic lignins were oxidized with purified isozyme Phanerochaete chrysosporium LiP. Gel permeation chromatography radiolabeled polymers showed that LiP catalyzed their give soluble lower-M(r) products. To lesser extent, enzyme also polymerized higher-M(r)...
Catalysis of the HzOz-dependent oxidation 3,4dimethoxybenzyl (veratryl) alcohol by hemoprotein ligninase isolated from wood-decaying fungus, Phanerochaete chrysosporium Burds, is characterized.The reaction yields veratraldehyde and exhibits a stoichiometry one Hz02 consumed per aldehyde formed.Ping-pong steady-state kinetics are observed for HzOz (KM = 29 PM) veratryl 72 at pH 3.5.The magnitude turnover number varies 2 to 3 s" this pH, depending on preparation enzyme.Each enzyme consists...
Phanerochaete chrysosporium is rapidly becoming a model system for the study of lignin biodegradation. Numerous studies on physiology, biochemistry, chemistry, and genetics this have been performed. However, P. not only fungus to lignin-degrading enzyme system. Many other ligninolytic species fungi, as well distantly related organisms which are known produce peroxidases, described in paper. In study, we demonstrated presence peroxidative enzymes nine previously investigated. The fungi...
Transposon insertions in Geobacter sulfurreducens GSU1501, part of an ATP-dependent exporter within operon polysaccharide biosynthesis genes, were previously shown to eliminate insoluble Fe(III) reduction and use electrode as electron acceptor. Replacement GSU1501 with a kanamycin resistance cassette produced similarly defective mutant, which could be partially complemented by expression GSU1500 GSU1505 trans. The Δ1501 mutant demonstrated limited cell-cell agglutination, enhanced attachment...
Research Article| March 01, 2004 Iron isotope fractionation during microbial reduction of iron: The importance adsorption G.A. Icopini; Icopini 1Department Geosciences, Pennsylvania State University, University Park, 16802, USA Search for other works by this author on: GSW Google Scholar A.D. Anbar; Anbar 2Department Earth and Environmental Science Department Chemistry, Rochester, New York 14627, S.S. Ruebush; Ruebush 3 Biochemistry Molecular Biology, M. Tien; Tien S.L. Brantley 4Department...
The possible involvement of hydrogen peroxide (H202)-derived hydroxyl radical ( OH) in lignin degradation (['"Cllignin + I4CO2) by Phanerochaete chrysosporium was investigated.When P. grown low nitrogen medium (2.4 m~ N), an increase the specific activity for HzOz production cell extracts observed to coincide with appearance ligninolytic and both activities appeared after culture entered stationary phase.The .OH cultures demonstrated a-keto-y-methiolbutyric acid-dependent formation...
This study examined the ligninase-catalysed degradation of lignin model compounds representing arylglycerol beta-aryl ether substructure, which is dominant one in polymer. Three dimeric were used, all methoxylated 3- and 4-positions ring (ring A) having various substituents beta-ether-linked aromatic B), so that competing reactions involving both rings could be compared. Studies products formed time courses their formation showed these are oxidized by ligninase (+ H2O2 + O2) A B. The major...
Oxalate is produced by numerous wood-degrading fungi. Our studies here show that the white-rot fungus Phanerochaete chrysosporium produces extracellular oxalate under conditions induce synthesis of ligninolytic system. Little or no was detected in cultures grown high nutrient nitrogen carbon. This identified and quantitated HPLC. Its identity further substantiated its decomposition enzyme oxidase. The content fluid (peaking at 60 microM) paralleled activity lignin-degrading enzyme, Mn...
Cellulose is the most abundant renewable polymer on Earth and a major component of plant cell wall. In vascular plants, cellulose synthesis catalyzed by large, plasma membrane-localized synthase complex (CSC), visualized as hexameric rosette structure. Three unique (CESA) isoforms are required for CSC assembly function. However, elucidation either number or stoichiometry CESAs within has remained elusive. this study, we show 1:1:1 between three Arabidopsis thaliana secondary wall isozymes:...
The hemoprotein ligninase of Phanerochaete chrysosporium Burds. catalyzes the oxidative cleavage lignin model dimers between C alpha and beta their propyl side chains. hitherto used give multiple products complex stoichiometries upon enzymatic oxidation. Here we present experiments with a new dimer, 1-(3,4-dimethoxyphenyl)-2-phenylethanediol (dimethoxyhydrobenzoin, DMHB) which is quantitatively cleaved by in air to benzaldehyde veratraldehyde according stoichiometry: 2DMHB + O2----2PhCHO...
The interaction of proteins implicated in dissimilatory metal reduction by Shewanella oneidensis MR-1 (outer membrane [OM] OmcA, MtrB, and MtrC; OM-associated protein MtrA; periplasmic CctA; cytoplasmic CymA) were characterized purification, analytical ultracentrifugation, cross-linking methods. Five these are heme proteins, OmcA (83 kDa), MtrC (75 MtrA (32 CctA (19 CymA (21 can be visualized after sodium dodecyl sulfate-polyacrylamide gel electrophoresis staining. We show for the first time...