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Li X, Gluth A, Feng S, Qian WJ, Yang B. Harnessing redox proteomics to study metabolic regulation and stress response in lignin-fed Rhodococci. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2023; 16:180. [PMID: 37986172 PMCID: PMC10662689 DOI: 10.1186/s13068-023-02424-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2023] [Accepted: 11/02/2023] [Indexed: 11/22/2023]
Abstract
BACKGROUND Rhodococci are studied for their bacterial ligninolytic capabilities and proclivity to accumulate lipids. Lignin utilization is a resource intensive process requiring a variety of redox active enzymes and cofactors for degradation as well as defense against the resulting toxic byproducts and oxidative conditions. Studying enzyme expression and regulation between carbon sources will help decode the metabolic rewiring that stymies lignin to lipid conversion in these bacteria. Herein, a redox proteomics approach was applied to investigate a fundamental driver of carbon catabolism and lipid anabolism: redox balance. RESULTS A consortium of Rhodococcus strains was employed in this study given its higher capacity for lignin degradation compared to monocultures. This consortium was grown on glucose vs. lignin under nitrogen limitation to study the importance of redox balance as it relates to nutrient availability. A modified bottom-up proteomics workflow was harnessed to acquire a general relationship between protein abundance and protein redox states. Global proteomics results affirm differential expression of enzymes involved in sugar metabolism vs. those involved in lignin degradation and aromatics metabolism. As reported previously, several enzymes in the lipid biosynthetic pathways were downregulated, whereas many involved in β-oxidation were upregulated. Interestingly, proteins involved in oxidative stress response were also upregulated perhaps in response to lignin degradation and aromatics catabolism, which require oxygen and reactive oxygen species and generate toxic byproducts. Enzymes displaying little-to-no change in abundance but differences in redox state were observed in various pathways for carbon utilization (e.g., β‑ketoadipate pathway), lipid metabolism, as well as nitrogen metabolism (e.g., purine scavenging/synthesis), suggesting potential mechanisms of redox-dependent regulation of metabolism. CONCLUSIONS Efficient lipid production requires a steady carbon and energy flux while balancing fundamental requirements for enzyme production and cell maintenance. For lignin, we theorize that this balance is difficult to establish due to resource expenditure for enzyme production and stress response. This is supported by significant changes to protein abundances and protein cysteine oxidation in various metabolic pathways and redox processes.
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Affiliation(s)
- Xiaolu Li
- Bioproducts, Sciences, and Engineering Laboratory, Department of Biological Systems Engineering, Washington State University, Richland, WA, 99354, USA
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - Austin Gluth
- Bioproducts, Sciences, and Engineering Laboratory, Department of Biological Systems Engineering, Washington State University, Richland, WA, 99354, USA
| | - Song Feng
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - Wei-Jun Qian
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - Bin Yang
- Bioproducts, Sciences, and Engineering Laboratory, Department of Biological Systems Engineering, Washington State University, Richland, WA, 99354, USA.
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, 99352, USA.
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2
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Cajnko MM, Oblak J, Grilc M, Likozar B. Enzymatic bioconversion process of lignin: mechanisms, reactions and kinetics. BIORESOURCE TECHNOLOGY 2021; 340:125655. [PMID: 34388661 DOI: 10.1016/j.biortech.2021.125655] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 07/20/2021] [Accepted: 07/22/2021] [Indexed: 06/13/2023]
Abstract
Lignin is a wasted renewable source of biomass-derived value-added chemicals. However, due to its material resistance to degradation, it remains highly underutilized. In order to develop new, catalysed and more environment friendly reaction processes for lignin valorization, science has turned a selective concentrated attention to microbial enzymes. This present work looks at the enzymes involved with the main reference focus on the different elementary mechanisms of action/conversion rate kinetics. Pathways, like with laccases/peroxidases, employ radicals, which more readily result in polymerization than de-polymerization. The β-etherase system interaction of proteins targets β-O-4 ether covalent bond, which targets lower molecular weight product species. Enzymatic activity is influenced by a wide variety of different factors which need to be considered in order to obtain the best functionality and synthesis yields.
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Affiliation(s)
- Miša Mojca Cajnko
- Department of Catalysis and Chemical Reaction Engineering, National Institute of Chemistry, NIC, Hajdrihova, 19, SI-1001 Ljubljana, Slovenia
| | - Jošt Oblak
- Department of Catalysis and Chemical Reaction Engineering, National Institute of Chemistry, NIC, Hajdrihova, 19, SI-1001 Ljubljana, Slovenia
| | - Miha Grilc
- Department of Catalysis and Chemical Reaction Engineering, National Institute of Chemistry, NIC, Hajdrihova, 19, SI-1001 Ljubljana, Slovenia
| | - Blaž Likozar
- Department of Catalysis and Chemical Reaction Engineering, National Institute of Chemistry, NIC, Hajdrihova, 19, SI-1001 Ljubljana, Slovenia.
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3
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Jankowski N, Urlacher VB, Koschorreck K. Two adjacent C-terminal mutations enable expression of aryl-alcohol oxidase from Pleurotus eryngii in Pichia pastoris. Appl Microbiol Biotechnol 2021; 105:7743-7755. [PMID: 34545417 PMCID: PMC8502153 DOI: 10.1007/s00253-021-11585-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 08/23/2021] [Accepted: 08/26/2021] [Indexed: 10/30/2022]
Abstract
Fungal aryl-alcohol oxidases (AAOs) are attractive biocatalysts because they selectively oxidize a broad range of aromatic and aliphatic allylic primary alcohols while yielding hydrogen peroxide as the only by-product. However, their use is hampered by challenging and often unsuccessful heterologous expression. Production of PeAAO1 from Pleurotus eryngii ATCC 90787 in Pichia pastoris failed, while PeAAO2 from P. eryngii P34 with an amino acid identity of 99% was expressed at high yields. By successively introducing mutations in PeAAO1 to mimic the sequence of PeAAO2, the double mutant PeAAO1 ER with mutations K583E and Q584R was constructed, that was successfully expressed in P. pastoris. Functional expression was enhanced up to 155 U/l via further replacements D361N (variant NER) or V367A (variant AER). Fed-batch cultivation of recombinant P. pastoris yielded up to 116 mg/l of active variants. Glycosylated PeAAO1 variants demonstrated high stability and catalytic efficiencies similar to PeAAO2. Interestingly, P. pastoris expressing PeAAO1 variant ER contained roughly 13 gene copies but showed similar volumetric activity as NER and AER with one to two gene copies and four times lower mRNA levels. Additional H-bonds and salt bridges introduced by mutations K583E and Q584R might facilitate heterologous expression by enhanced protein folding.Key points• PeAAO1 not expressed in P. pastoris and PeAAO2 well-expressed in Pichia differ at 7 positions.• Expression of PeAAO1 in P. pastoris achieved through mutagenesis based on PeAAO2 sequence.• Combination of K583E and Q584R is essential for expression of PeAAO1 in P. pastoris.
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Affiliation(s)
- Nina Jankowski
- Institute of Biochemistry, Heinrich-Heine-University Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
| | - Vlada B Urlacher
- Institute of Biochemistry, Heinrich-Heine-University Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
| | - Katja Koschorreck
- Institute of Biochemistry, Heinrich-Heine-University Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany.
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4
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Saldarriaga-Hernández S, Velasco-Ayala C, Leal-Isla Flores P, de Jesús Rostro-Alanis M, Parra-Saldivar R, Iqbal HMN, Carrillo-Nieves D. Biotransformation of lignocellulosic biomass into industrially relevant products with the aid of fungi-derived lignocellulolytic enzymes. Int J Biol Macromol 2020; 161:1099-1116. [PMID: 32526298 DOI: 10.1016/j.ijbiomac.2020.06.047] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 06/03/2020] [Accepted: 06/05/2020] [Indexed: 02/08/2023]
Abstract
Lignocellulosic material has drawn significant attention among the scientific community due to its year-round availability as a renewable resource for industrial consumption. Being an economic substrate alternative, various industries are reevaluating processes to incorporate derived compounds from these materials. Varieties of fungi and bacteria have the ability to depolymerize lignocellulosic biomass by synthesizing degrading enzymes. Owing to catalytic activity stability and high yields of conversion, lignocellulolytic enzymes derived from fungi currently have a high spectrum of industrial applications. Moreover, these materials are cost effective, eco-friendly and nontoxic while having a low energy input. Techno-economic analysis for current enzyme production technologies indicates that synthetic production is not commercially viable. Instead, the economic projection of the use of naturally-produced ligninolytic enzymes is promising. This approach may improve the economic feasibility of the process by lowering substrate expenses and increasing lignocellulosic by-product's added value. The present review will discuss the classification and enzymatic degradation pathways of lignocellulolytic biomass as well as the potential and current industrial applications of the involved fungal enzymes.
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Affiliation(s)
- Sara Saldarriaga-Hernández
- Tecnologico de Monterrey, Escuela de Ingenieria y Ciencias, Campus Monterrey, Ave. Eugenio Garza Sada 2501, Monterrey, Nuevo Leon 64849, Mexico
| | - Carolina Velasco-Ayala
- Tecnologico de Monterrey, Escuela de Ingenieria y Ciencias, Campus Monterrey, Ave. Eugenio Garza Sada 2501, Monterrey, Nuevo Leon 64849, Mexico
| | - Paulina Leal-Isla Flores
- Tecnologico de Monterrey, Escuela de Ingenieria y Ciencias, Campus Monterrey, Ave. Eugenio Garza Sada 2501, Monterrey, Nuevo Leon 64849, Mexico
| | - Magdalena de Jesús Rostro-Alanis
- Tecnologico de Monterrey, Escuela de Ingenieria y Ciencias, Campus Monterrey, Ave. Eugenio Garza Sada 2501, Monterrey, Nuevo Leon 64849, Mexico
| | - Roberto Parra-Saldivar
- Tecnologico de Monterrey, Escuela de Ingenieria y Ciencias, Campus Monterrey, Ave. Eugenio Garza Sada 2501, Monterrey, Nuevo Leon 64849, Mexico
| | - Hafiz M N Iqbal
- Tecnologico de Monterrey, Escuela de Ingenieria y Ciencias, Campus Monterrey, Ave. Eugenio Garza Sada 2501, Monterrey, Nuevo Leon 64849, Mexico
| | - Danay Carrillo-Nieves
- Tecnologico de Monterrey, Escuela de Ingenieria y Ciencias, Av. General Ramón Corona 2514, Nuevo México, Zapopan C.P. 45138, Jalisco, Mexico.
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5
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Kadowaki MAS, Higasi PMR, de Godoy MO, de Araújo EA, Godoy AS, Prade RA, Polikarpov I. Enzymatic versatility and thermostability of a new aryl-alcohol oxidase from Thermothelomyces thermophilus M77. Biochim Biophys Acta Gen Subj 2020; 1864:129681. [PMID: 32653619 DOI: 10.1016/j.bbagen.2020.129681] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 06/14/2020] [Accepted: 06/30/2020] [Indexed: 01/23/2023]
Abstract
Background Fungal aryl-alcohol oxidases (AAOx) are extracellular flavoenzymes that belong to glucose-methanol-choline oxidoreductase family and are responsible for the selective conversion of primary aromatic alcohols into aldehydes and aromatic aldehydes to their corresponding acids, with concomitant production of hydrogen peroxide (H2O2) as by-product. The H2O2 can be provided to lignin degradation pathway, a biotechnological property explored in biofuel production. In the thermophilic fungus Thermothelomyces thermophilus (formerly Myceliophthora thermophila), just one AAOx was identified in the exo-proteome. Methods The glycosylated and non-refolded crystal structure of an AAOx from T. thermophilus at 2.6 Å resolution was elucidated by X-ray crystallography combined with small-angle X-ray scattering (SAXS) studies. Moreover, biochemical analyses were carried out to shed light on enzyme substrate specificity and thermostability. Results This flavoenzyme harbors a flavin adenine dinucleotide as a cofactor and is able to oxidize aromatic substrates and 5-HMF. Our results also show that the enzyme has similar oxidation rates for bulky or simple aromatic substrates such as cinnamyl and veratryl alcohols. Moreover, the crystal structure of MtAAOx reveals an open active site, which might explain observed specificity of the enzyme. Conclusions MtAAOx shows previously undescribed structural differences such as a fully accessible catalytic tunnel, heavy glycosylation and Ca2+ binding site providing evidences for thermostability and activity of the enzymes from AA3_2 subfamily. General significance Structural and biochemical analyses of MtAAOx could be important for comprehension of aryl-alcohol oxidases structure-function relationships and provide additional molecular tools to be used in future biotechnological applications.
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Affiliation(s)
- Marco Antonio Seiki Kadowaki
- São Carlos Institute of Physics, University of São Paulo, Av. Trabalhador São-carlense, 400, São Carlos, SP 13566-590, Brazil.
| | - Paula Miwa Rabelo Higasi
- São Carlos Institute of Physics, University of São Paulo, Av. Trabalhador São-carlense, 400, São Carlos, SP 13566-590, Brazil
| | - Mariana Ortiz de Godoy
- São Carlos Institute of Physics, University of São Paulo, Av. Trabalhador São-carlense, 400, São Carlos, SP 13566-590, Brazil
| | - Evandro Ares de Araújo
- São Carlos Institute of Physics, University of São Paulo, Av. Trabalhador São-carlense, 400, São Carlos, SP 13566-590, Brazil
| | - Andre Schutzer Godoy
- São Carlos Institute of Physics, University of São Paulo, Av. Trabalhador São-carlense, 400, São Carlos, SP 13566-590, Brazil
| | - Rolf Alexander Prade
- Departments of Microbiology & Molecular Genetics and Biochemistry & Molecular Biology, Oklahoma State University, OK, USA
| | - Igor Polikarpov
- São Carlos Institute of Physics, University of São Paulo, Av. Trabalhador São-carlense, 400, São Carlos, SP 13566-590, Brazil.
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6
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Viña-Gonzalez J, Alcalde M. Directed evolution of the aryl-alcohol oxidase: Beyond the lab bench. Comput Struct Biotechnol J 2020; 18:1800-1810. [PMID: 32695272 PMCID: PMC7358221 DOI: 10.1016/j.csbj.2020.06.037] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 06/19/2020] [Accepted: 06/20/2020] [Indexed: 11/22/2022] Open
Abstract
Aryl-alcohol oxidase (AAO) is a fungal GMC flavoprotein secreted by white-rot fungi that supplies H2O2 to the ligninolytic consortium. This enzyme can oxidize a wide array of aromatic alcohols in a highly enantioselective manner, an important trait in organic synthesis. The best strategy to adapt AAO to industrial needs is to engineer its properties by directed evolution, aided by computational analysis. The aim of this review is to describe the strategies and challenges we faced when undertaking laboratory evolution of AAO. After a comprehensive introduction into the structure of AAO, its function and potential applications, the different directed evolution enterprises designed to express the enzyme in an active and soluble form in yeast are described, as well as those to unlock new activities involving the oxidation of secondary aromatic alcohols and the synthesis of furandicarboxylic acids.
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Affiliation(s)
- Javier Viña-Gonzalez
- Department of Biocatalysis, Institute of Catalysis, CSIC, Cantoblanco, 28049 Madrid, Spain
| | - Miguel Alcalde
- Department of Biocatalysis, Institute of Catalysis, CSIC, Cantoblanco, 28049 Madrid, Spain
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7
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Liu E, Li M, Abdella A, Wilkins MR. Development of a cost-effective medium for submerged production of fungal aryl alcohol oxidase using a genetically modified Aspergillus nidulans strain. BIORESOURCE TECHNOLOGY 2020; 305:123038. [PMID: 32120232 DOI: 10.1016/j.biortech.2020.123038] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 02/13/2020] [Accepted: 02/15/2020] [Indexed: 06/10/2023]
Abstract
Aryl alcohol oxidase (AAO), an extracellular H2O2-providing enzyme, plays a central role in lignin depolymerization. Cost-effective production of AAO has not been achieved, due to the low yield of enzyme-producing microorganisms and the high cost of fermentation media. This study aims to develop a cost-effective medium for high-yield production of AAO in submerged culture using a recombinant Aspergillus nidulans strain. Results demonstrate that corn steep liquor (CSL) was a rich but inexpensive nitrogen source for AAO production, and CSL can provide enough trace metals and vitamins (i.e. pyridoxine) for A. nidulans. A 2-level Plackett-Burman design was utilized to determine the main affecting factors in AAO production. The medium was further optimized by a 3-level Box-Behnken design to obtain the optimum medium component concentrations (61.0 g/L maltose, 26.4 g/L CSL, and 13.8 g/L NaNO3). The greatest AAO activity achieved was 1021 U/L with a protein concentration of 0.75 g/L.
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Affiliation(s)
- Enshi Liu
- Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln, NE 68583, USA
| | - Mengxing Li
- Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln, NE 68583, USA; Department of Statistics, University of Nebraska-Lincoln, Lincoln, NE 68583, USA
| | - Asmaa Abdella
- Department of Industrial Biotechnology, Genetic Engineering and Biotechnology Research Institute, University of Sadat City, Sadat City 22857, Egypt; Industrial Agricultural Products Center, University of Nebraska-Lincoln, Lincoln, NE 68583, USA
| | - Mark R Wilkins
- Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln, NE 68583, USA; Industrial Agricultural Products Center, University of Nebraska-Lincoln, Lincoln, NE 68583, USA; Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE 68588, USA.
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8
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Chan JC, Paice M, Zhang X. Enzymatic Oxidation of Lignin: Challenges and Barriers Toward Practical Applications. ChemCatChem 2019. [DOI: 10.1002/cctc.201901480] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Jou C. Chan
- Voiland School of Chemical Engineering and Bioengineering Washington State University 2710 Crimson Way Richland WA-99354 USA
| | - Michael Paice
- FPInnovations Pulp Paper & Bioproducts 2665 East Mall Vancouver BC V6T 1Z4 Canada
| | - Xiao Zhang
- Voiland School of Chemical Engineering and Bioengineering Washington State University 2710 Crimson Way Richland WA-99354 USA
- Pacific Northwest National Laboratory 520 Battelle Boulevard P.O. Box 999, MSIN P8-60 Richland WA-99352 USA
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9
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Viña‐Gonzalez J, Jimenez‐Lalana D, Sancho F, Serrano A, Martinez AT, Guallar V, Alcalde M. Structure‐Guided Evolution of Aryl Alcohol Oxidase from
Pleurotus eryngii
for the Selective Oxidation of Secondary Benzyl Alcohols. Adv Synth Catal 2019. [DOI: 10.1002/adsc.201900134] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Javier Viña‐Gonzalez
- Department of Biocatalysis, Institute of CatalysisCSIC, Cantoblanco 28049 Madrid Spain Fax: (+31)-91 5854760; phone: (+34)-91 5854806
| | - Diego Jimenez‐Lalana
- Department of Biocatalysis, Institute of CatalysisCSIC, Cantoblanco 28049 Madrid Spain Fax: (+31)-91 5854760; phone: (+34)-91 5854806
| | - Ferran Sancho
- Barcelona Supercomputing Center Jordi Girona 31 08034 Barcelona Spain
| | - Ana Serrano
- Biological Research CenterCSIC Ramiro de Maeztu 9 28040 Madrid Spain
| | - Angel T. Martinez
- Biological Research CenterCSIC Ramiro de Maeztu 9 28040 Madrid Spain
| | - Victor Guallar
- Barcelona Supercomputing Center Jordi Girona 31 08034 Barcelona Spain
- ICREA Passeig Lluís Companys 23 08010 Barcelona Spain
| | - Miguel Alcalde
- Department of Biocatalysis, Institute of CatalysisCSIC, Cantoblanco 28049 Madrid Spain Fax: (+31)-91 5854760; phone: (+34)-91 5854806
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Wongnate T, Surawatanawong P, Chuaboon L, Lawan N, Chaiyen P. The Mechanism of Sugar C−H Bond Oxidation by a Flavoprotein Oxidase Occurs by a Hydride Transfer Before Proton Abstraction. Chemistry 2019; 25:4460-4471. [DOI: 10.1002/chem.201806078] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 01/16/2019] [Indexed: 11/06/2022]
Affiliation(s)
- Thanyaporn Wongnate
- School of Biomolecular Science & EngineeringVidyasirimedhi Institute of Science and Technology (VISTEC), Wangchan Valley Rayong 21210 Thailand
| | - Panida Surawatanawong
- Department of Chemistry and Center of Excellence, for Innovation in ChemistryMahidol University Bangkok 10400 Thailand
| | - Litavadee Chuaboon
- Department of Biochemistry and Center for Excellence, in Protein and Enzyme Technology, Faculty of ScienceMahidol University Bangkok 10400 Thailand
| | - Narin Lawan
- Department of Chemistry, Faculty of ScienceChiang Mai University Chiang Mai 50200 Thailand
| | - Pimchai Chaiyen
- School of Biomolecular Science & EngineeringVidyasirimedhi Institute of Science and Technology (VISTEC), Wangchan Valley Rayong 21210 Thailand
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11
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Serrano A, Sancho F, Viña-González J, Carro J, Alcalde M, Guallar V, Martínez AT. Switching the substrate preference of fungal aryl-alcohol oxidase: towards stereoselective oxidation of secondary benzyl alcohols. Catal Sci Technol 2019. [DOI: 10.1039/c8cy02447b] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Using PELE computational simulations the ability to deracemize secondary benzylic alcohols was introduced (by I500M/F501W double mutation) in stereoselective AAO.
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Affiliation(s)
- Ana Serrano
- Centro de Investigaciones Biológicas
- CSIC
- E-28040 Madrid
- Spain
| | - Ferran Sancho
- Barcelona Supercomputing Center
- E-08034 Barcelona
- Spain
| | | | - Juan Carro
- Centro de Investigaciones Biológicas
- CSIC
- E-28040 Madrid
- Spain
| | - Miguel Alcalde
- Department of Biocatalysis
- Institute of Catalysis
- CSIC
- Madrid
- Spain
| | - Victor Guallar
- Barcelona Supercomputing Center
- E-08034 Barcelona
- Spain
- ICREA
- Barcelona
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12
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Gygli G, de Vries RP, van Berkel WJ. On the origin of vanillyl alcohol oxidases. Fungal Genet Biol 2018; 116:24-32. [DOI: 10.1016/j.fgb.2018.04.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 03/24/2018] [Accepted: 04/03/2018] [Indexed: 11/16/2022]
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13
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Carro J, Amengual-Rigo P, Sancho F, Medina M, Guallar V, Ferreira P, Martínez AT. Multiple implications of an active site phenylalanine in the catalysis of aryl-alcohol oxidase. Sci Rep 2018; 8:8121. [PMID: 29802285 PMCID: PMC5970180 DOI: 10.1038/s41598-018-26445-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 05/11/2018] [Indexed: 01/15/2023] Open
Abstract
Aryl-alcohol oxidase (AAO) has demonstrated to be an enzyme with a bright future ahead due to its biotechnological potential in deracemisation of chiral compounds, production of bioplastic precursors and other reactions of interest. Expanding our understanding on the AAO reaction mechanisms, through the investigation of its structure-function relationships, is crucial for its exploitation as an industrial biocatalyst. In this regard, previous computational studies suggested an active role for AAO Phe397 at the active-site entrance. This residue is located in a loop that partially covers the access to the cofactor forming a bottleneck together with two other aromatic residues. Kinetic and affinity spectroscopic studies, complemented with computational simulations using the recently developed adaptive-PELE technology, reveal that the Phe397 residue is important for product release and to help the substrates attain a catalytically relevant position within the active-site cavity. Moreover, removal of aromaticity at the 397 position impairs the oxygen-reduction activity of the enzyme. Experimental and computational findings agree very well in the timing of product release from AAO, and the simulations help to understand the experimental results. This highlights the potential of adaptive-PELE to provide answers to the questions raised by the empirical results in the study of enzyme mechanisms.
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Affiliation(s)
- Juan Carro
- Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, E-28040, Madrid, Spain
| | - Pep Amengual-Rigo
- Barcelona Supercomputing Center, Jordi Girona 31, E-08034, Barcelona, Spain
| | - Ferran Sancho
- Barcelona Supercomputing Center, Jordi Girona 31, E-08034, Barcelona, Spain
| | - Milagros Medina
- Department of Biochemistry and Cellular and Molecular Biology, and BIFI, University of Zaragoza, E-50009, Zaragoza, Spain
| | - Victor Guallar
- Barcelona Supercomputing Center, Jordi Girona 31, E-08034, Barcelona, Spain. .,ICREA, Passeig Lluís Companys 23, E-08010, Barcelona, Spain.
| | - Patricia Ferreira
- Department of Biochemistry and Cellular and Molecular Biology, and BIFI, University of Zaragoza, E-50009, Zaragoza, Spain.
| | - Angel T Martínez
- Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, E-28040, Madrid, Spain.
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14
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Characterization of an aryl-alcohol oxidase from the plant saprophytic basidiomycete Coprinopsis cinerea with broad substrate specificity against aromatic alcohols. Biotechnol Lett 2018; 40:1077-1086. [PMID: 29785669 DOI: 10.1007/s10529-018-2534-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 02/28/2018] [Indexed: 11/27/2022]
Abstract
OBJECTIVES The aim of the study was to obtain information about the enzymatic properties of aryl-alcohol oxidase from the plant saprophytic basidiomycete Coprinopsis cinerea (rCcAAO), which is classified into the auxiliary activities family 3 subfamily 2 (AA3_2). RESULTS The gene encoding AAO from the plant saprophytic basidiomycete Coprinopsis cinerea (CcAAO) was cloned, and the recombinant CcAAO (rCcAAO) was heterologously expressed in the methylotrophic yeast Pichia pastoris. The purified rCcAAO showed significant activity not only against trans,trans-2,4-hexadien-1-ol but also against a broad range of aromatic alcohols including aromatic compounds that were reported to be poor substrates for known AAOs. Moreover, site-directed mutagenesis analysis demonstrated that mutants with substitutions from leucine to phenylalanine and tryptophan at position 416 exhibited decreases of activity for aromatic alcohols but still maintained the activity for trans,trans-2,4-hexadien-1-ol. CONCLUSIONS Leucine 416 in CcAAO contributes to the broad substrate specificity against various aromatic alcohols, which is useful for the production of hydrogen peroxide using this enzyme.
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Carro J, Ferreira P, Martínez AT, Gadda G. Stepwise Hydrogen Atom and Proton Transfers in Dioxygen Reduction by Aryl-Alcohol Oxidase. Biochemistry 2018; 57:1790-1797. [DOI: 10.1021/acs.biochem.8b00106] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Juan Carro
- Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, E-28040 Madrid, Spain
| | - Patricia Ferreira
- Departament of Biochemistry and Cellular and Molecular Biology and Institute for Biocomputation and Physics of Complex Systems (BIFI), University of Zaragoza, E-50009 Zaragoza, Spain
| | - Angel T. Martínez
- Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, E-28040 Madrid, Spain
| | - Giovanni Gadda
- Department of Chemistry, Department of Biology, Center for Biotechnology and Drug Design, and Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, Georgia 30302-3965, United States
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Lamazares E, Vega S, Ferreira P, Medina M, Galano-Frutos JJ, Martínez-Júlvez M, Velázquez-Campoy A, Sancho J. Direct examination of the relevance for folding, binding and electron transfer of a conserved protein folding intermediate. Phys Chem Chem Phys 2018; 19:19021-19031. [PMID: 28702545 DOI: 10.1039/c7cp02606d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Near the minimum free energy basin of proteins where the native ensemble resides, partly unfolded conformations of slightly higher energy can be significantly populated under native conditions. It has been speculated that they play roles in molecular recognition and catalysis, but they might represent contemporary features of the evolutionary process without functional relevance. Obtaining conclusive evidence on these alternatives is difficult because it requires comparing the performance of a given protein when populating and when not populating one such intermediate, in otherwise identical conditions. Wild type apoflavodoxin populates under native conditions a partly unfolded conformation (10% of molecules) whose unstructured region includes the binding sites for the FMN cofactor and for redox partner proteins. We recently engineered a thermostable variant where the intermediate is no longer detectable. Using the wild type and variant, we assess the relevance of the intermediate comparing folding kinetics, cofactor binding kinetics, cofactor affinity, X-ray structure, intrinsic dynamics, redox potential of the apoflavodoxin-cofactor complex (Fld), its affinity for partner protein FNR, and electron transfer rate within the Fld/FNR physiological complex. Our data strongly suggest the intermediate state, conserved in long-chain apoflavodoxins, is not required for the correct assembly of flavodoxin nor does it contribute to shape its electron transfer properties. This analysis can be applied to evaluate other native basin intermediates.
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Affiliation(s)
- Emilio Lamazares
- Biocomputation and Complex Systems Physics Institute (BIFI)-Joint Units: BIFI-IQFR (CSIC) and GBsC-CSIC, Universidad de Zaragoza, Zaragoza, Spain and Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain
| | - Sonia Vega
- Biocomputation and Complex Systems Physics Institute (BIFI)-Joint Units: BIFI-IQFR (CSIC) and GBsC-CSIC, Universidad de Zaragoza, Zaragoza, Spain
| | - Patricia Ferreira
- Biocomputation and Complex Systems Physics Institute (BIFI)-Joint Units: BIFI-IQFR (CSIC) and GBsC-CSIC, Universidad de Zaragoza, Zaragoza, Spain and Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain
| | - Milagros Medina
- Biocomputation and Complex Systems Physics Institute (BIFI)-Joint Units: BIFI-IQFR (CSIC) and GBsC-CSIC, Universidad de Zaragoza, Zaragoza, Spain and Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain
| | - Juan J Galano-Frutos
- Biocomputation and Complex Systems Physics Institute (BIFI)-Joint Units: BIFI-IQFR (CSIC) and GBsC-CSIC, Universidad de Zaragoza, Zaragoza, Spain and Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain
| | - Marta Martínez-Júlvez
- Biocomputation and Complex Systems Physics Institute (BIFI)-Joint Units: BIFI-IQFR (CSIC) and GBsC-CSIC, Universidad de Zaragoza, Zaragoza, Spain and Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain
| | - Adrián Velázquez-Campoy
- Biocomputation and Complex Systems Physics Institute (BIFI)-Joint Units: BIFI-IQFR (CSIC) and GBsC-CSIC, Universidad de Zaragoza, Zaragoza, Spain and Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain and Fundación ARAID, Gobierno de Aragón, Spain and Aragon Health Research Institute (IIS Aragón), Universidad de Zaragoza, Zaragoza, Spain.
| | - Javier Sancho
- Biocomputation and Complex Systems Physics Institute (BIFI)-Joint Units: BIFI-IQFR (CSIC) and GBsC-CSIC, Universidad de Zaragoza, Zaragoza, Spain and Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain and Aragon Health Research Institute (IIS Aragón), Universidad de Zaragoza, Zaragoza, Spain.
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Carro J, Martínez-Júlvez M, Medina M, Martínez AT, Ferreira P. Protein dynamics promote hydride tunnelling in substrate oxidation by aryl-alcohol oxidase. Phys Chem Chem Phys 2018; 19:28666-28675. [PMID: 29043303 DOI: 10.1039/c7cp05904c] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The temperature dependence of hydride transfer from the substrate to the N5 of the FAD cofactor during the reductive half-reaction of Pleurotus eryngii aryl-alcohol oxidase (AAO) is assessed here. Kinetic isotope effects on both the pre-steady state reduction of the enzyme and its steady-state kinetics, with differently deuterated substrates, suggest an environmentally-coupled quantum-mechanical tunnelling process. Moreover, those kinetic data, along with the crystallographic structure of the enzyme in complex with a substrate analogue, indicate that AAO shows a pre-organized active site that would only require the approaching of the hydride donor and acceptor for the tunnelled transfer to take place. Modification of the enzyme's active-site architecture by replacement of Tyr92, a residue establishing hydrophobic interactions with the substrate analogue in the crystal structure, in the Y92F, Y92L and Y92W variants resulted in different temperature dependence patterns that indicated a role of this residue in modulating the transfer reaction.
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Affiliation(s)
- Juan Carro
- Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, E-28040, Madrid, Spain.
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Orellana R, Chaput G, Markillie LM, Mitchell H, Gaffrey M, Orr G, DeAngelis KM. Multi-time series RNA-seq analysis of Enterobacter lignolyticus SCF1 during growth in lignin-amended medium. PLoS One 2017; 12:e0186440. [PMID: 29049419 PMCID: PMC5648182 DOI: 10.1371/journal.pone.0186440] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 10/02/2017] [Indexed: 12/11/2022] Open
Abstract
The production of lignocellulosic-derived biofuels is a highly promising source of alternative energy, but it has been constrained by the lack of a microbial platform capable to efficiently degrade this recalcitrant material and cope with by-products that can be toxic to cells. Species that naturally grow in environments where carbon is mainly available as lignin are promising for finding new ways of removing the lignin that protects cellulose for improved conversion of lignin to fuel precursors. Enterobacter lignolyticus SCF1 is a facultative anaerobic Gammaproteobacteria isolated from tropical rain forest soil collected in El Yunque forest, Puerto Rico under anoxic growth conditions with lignin as sole carbon source. Whole transcriptome analysis of SCF1 during E.lignolyticus SCF1 lignin degradation was conducted on cells grown in the presence (0.1%, w/w) and the absence of lignin, where samples were taken at three different times during growth, beginning of exponential phase, mid-exponential phase and beginning of stationary phase. Lignin-amended cultures achieved twice the cell biomass as unamended cultures over three days, and in this time degraded 60% of lignin. Transcripts in early exponential phase reflected this accelerated growth. A complement of laccases, aryl-alcohol dehydrogenases, and peroxidases were most up-regulated in lignin amended conditions in mid-exponential and early stationary phases compared to unamended growth. The association of hydrogen production by way of the formate hydrogenlyase complex with lignin degradation suggests a possible value added to lignin degradation in the future.
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Affiliation(s)
- Roberto Orellana
- Centro de Biotecnología Daniel Alkalay Lowitt, Universidad Técnica Federico Santa María, Valparaíso, Chile
| | - Gina Chaput
- Microbiology Department, University of Massachusetts Amherst, Amherst, United States of America
| | - Lye Meng Markillie
- Pacific Northwest National Laboratory, Richland, Washington, United States of America
| | - Hugh Mitchell
- Pacific Northwest National Laboratory, Richland, Washington, United States of America
| | - Matt Gaffrey
- Pacific Northwest National Laboratory, Richland, Washington, United States of America
| | - Galya Orr
- Pacific Northwest National Laboratory, Richland, Washington, United States of America
| | - Kristen M. DeAngelis
- Microbiology Department, University of Massachusetts Amherst, Amherst, United States of America
- * E-mail:
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Basotra N, Kaur B, Di Falco M, Tsang A, Chadha BS. Mycothermus thermophilus (Syn. Scytalidium thermophilum): Repertoire of a diverse array of efficient cellulases and hemicellulases in the secretome revealed. BIORESOURCE TECHNOLOGY 2016; 222:413-421. [PMID: 27744242 DOI: 10.1016/j.biortech.2016.10.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 10/04/2016] [Accepted: 10/05/2016] [Indexed: 05/25/2023]
Abstract
Mycothermus thermophilus (Syn. Scytalidium thermophilum/Humicola insolens), a thermophilic fungus, is being reported to produce appreciable titers of cellulases and hemicellulases during shake flask culturing on cellulose/wheat-bran/rice straw based production medium. The sequential and differential expression profile of endoglucanases, β-glucosidases, cellobiohydrolases and xylanases using zymography was studied. Mass spectrometry analysis of secretome (Q-TOF LC/MS) revealed a total of 240 proteins with 92 CAZymes of which 62 glycosyl hydrolases belonging to 30 different families were present. Cellobiohydrolase I (17.42%), β glucosidase (8.69%), endoglucanase (6.2%), xylanase (4.16%) and AA9 (3.95%) were the major proteins in the secretome. In addition, carbohydrate esterases, polysaccharide lyases, auxiliary activity and a variety of carbohydrate binding modules (CBM) were identified using genomic database of the culture indicating to an elaborate genetic potential of this strain for hydrolysis of lignocellulosics. The cellulases from the strain hydrolyzed alkali treated rice straw and bagasse into fermentable sugars efficiently.
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Affiliation(s)
- Neha Basotra
- Department of Microbiology, Guru Nanak Dev University, Amritsar 143005, Punjab, India.
| | - Baljit Kaur
- Department of Microbiology, Guru Nanak Dev University, Amritsar 143005, Punjab, India.
| | - Marcos Di Falco
- Center for Structural and Functional Genomics, Concordia University, 7141 Sherbrooke Street West, Montreal, Quebec H4B 1R6, Canada.
| | - Adrian Tsang
- Center for Structural and Functional Genomics, Concordia University, 7141 Sherbrooke Street West, Montreal, Quebec H4B 1R6, Canada.
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Structures of almond hydroxynitrile lyase isoenzyme 5 provide a rationale for the lack of oxidoreductase activity in flavin dependent HNLs. J Biotechnol 2016; 235:24-31. [DOI: 10.1016/j.jbiotec.2016.04.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Revised: 04/06/2016] [Accepted: 04/07/2016] [Indexed: 11/21/2022]
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21
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Barad S, Sela N, Kumar D, Kumar-Dubey A, Glam-Matana N, Sherman A, Prusky D. Fungal and host transcriptome analysis of pH-regulated genes during colonization of apple fruits by Penicillium expansum. BMC Genomics 2016; 17:330. [PMID: 27146851 PMCID: PMC4855365 DOI: 10.1186/s12864-016-2665-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 04/26/2016] [Indexed: 11/26/2022] Open
Abstract
Background Penicillium expansum is a destructive phytopathogen that causes decay in deciduous fruits during postharvest handling and storage. During colonization the fungus secretes D-gluconic acid (GLA), which modulates environmental pH and regulates mycotoxin accumulation in colonized tissue. Till now no transcriptomic analysis has addressed the specific contribution of the pathogen's pH regulation to the P. expansum colonization process. For this purpose total RNA from the leading edge of P. expansum-colonized apple tissue of cv. 'Golden Delicious' and from fungal cultures grown under pH 4 or 7 were sequenced and their gene expression patterns were compared. Results We present a large-scale analysis of the transcriptome data of P. expansum and apple response to fungal colonization. The fungal analysis revealed nine different clusters of gene expression patterns that were divided among three major groups in which the colonized tissue showed, respectively: (i) differing transcript expression patterns between mycelial growth at pH 4 and pH 7; (ii) similar transcript expression patterns of mycelial growth at pH 4; and (iii) similar transcript expression patterns of mycelial growth at pH 7. Each group was functionally characterized in order to decipher genes that are important for pH regulation and also for colonization of apple fruits by Penicillium. Furthermore, comparison of gene expression of healthy apple tissue with that of colonized tissue showed that differentially expressed genes revealed up-regulation of the jasmonic acid and mevalonate pathways, and also down-regulation of the glycogen and starch biosynthesis pathways. Conclusions Overall, we identified important genes and functionalities of P. expansum that were controlled by the environmental pH. Differential expression patterns of genes belonging to the same gene family suggest that genes were selectively activated according to their optimal environmental conditions (pH, in vitro or in vivo) to enable the fungus to cope with varying conditions and to make optimal use of available enzymes. Comparison between the activation of the colonized host's gene responses by alkalizing Colletotrichum gloeosporioides and acidifying P. expansum pathogens indicated similar gene response patterns, but stronger responses to P. expansum, suggesting the importance of acidification by P. expansum as a factor in its increased aggressiveness. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-2665-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Shiri Barad
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization, the Volcani Center, Bet Dagan, 50250, Israel.,Department of Plant Pathology and Microbiology, Robert H. Smith Faculty of Agriculture, Food and Environment, Hebrew University of Jerusalem, Rehovot, 76100, Israel
| | - Noa Sela
- Department of Plant Pathology and Weed Research, ARO, the Volcani Center, Bet Dagan, 50250, Israel
| | - Dilip Kumar
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization, the Volcani Center, Bet Dagan, 50250, Israel
| | - Amit Kumar-Dubey
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization, the Volcani Center, Bet Dagan, 50250, Israel
| | - Nofar Glam-Matana
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization, the Volcani Center, Bet Dagan, 50250, Israel.,Department of Plant Pathology and Microbiology, Robert H. Smith Faculty of Agriculture, Food and Environment, Hebrew University of Jerusalem, Rehovot, 76100, Israel
| | - Amir Sherman
- Genomics Unit, ARO, the Volcani Center, Bet Dagan, 50250, Israel
| | - Dov Prusky
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization, the Volcani Center, Bet Dagan, 50250, Israel.
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Schneider WDH, Gonçalves TA, Uchima CA, Couger MB, Prade R, Squina FM, Dillon AJP, Camassola M. Penicillium echinulatum secretome analysis reveals the fungi potential for degradation of lignocellulosic biomass. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:66. [PMID: 26989443 PMCID: PMC4794826 DOI: 10.1186/s13068-016-0476-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Accepted: 03/02/2016] [Indexed: 05/25/2023]
Abstract
BACKGROUND The enzymatic degradation of lignocellulosic materials by fungal enzyme systems has been extensively studied due to its effectiveness in the liberation of fermentable sugars for bioethanol production. Recently, variants of the fungus Penicillium echinulatum have been described as a great producer of cellulases and considered a promising strain for the bioethanol industry. RESULTS Penicillium echinulatum, wild-type 2HH and its mutant strain S1M29, were grown on four different carbon sources: cellulose, sugar cane bagasse pretreated by steam explosion (SCB), glucose, and glycerol for 120 h. Samples collected at 24, 96, and 120 h were used for enzymatic measurement, and the 96-h one was also used for secretome analysis by 1D-PAGE LC-MS/MS. A total of 165 proteins were identified, and more than one-third of these proteins belong to CAZy families. Glycosyl hydrolases (GH) are the most abundant group, being represented in larger quantities by GH3, 5, 17, 43, and 72. Cellobiohydrolases, endoglucanases, β-glycosidases, xylanases, β-xylosidases, and mannanases were found, and in minor quantities, pectinases, ligninases, and amylases were also found. Swollenin and esterases were also identified. CONCLUSIONS Our study revealed differences in the two strains of P. echinulatum in several aspects in which the mutation improved the production of enzymes related to lignocellulosic biomass deconstruction. Considering the spectral counting analysis, the mutant strain S1M29 was more efficient in the production of enzymes involved in cellulose and hemicellulose degradation, despite having a nearly identical CAZy enzymatic repertoire. Moreover, S1M29 secretes more quantities of protein on SCB than on cellulose, relevant information when considering the production of cellulases using raw materials at low cost. Glucose, and especially glycerol, were used mainly for the production of amylases and ligninases.
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Affiliation(s)
- Willian Daniel Hahn Schneider
- />Enzymes and Biomass Laboratory, Institute of Biotechnology, University of Caxias do Sul, Francisco Getúlio Vargas Street 1130, Caxias Do Sul, RS 95070-560 Brazil
| | - Thiago Augusto Gonçalves
- />Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Giuseppe Maximo Scolfaro 10.000, Campinas, São Paulo 13083-970 Brazil
- />Department of Biochemistry, Institute of Biology, State University of Campinas (UNICAMP), Campinas, São Paulo Brazil
| | - Cristiane Akemi Uchima
- />Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Giuseppe Maximo Scolfaro 10.000, Campinas, São Paulo 13083-970 Brazil
| | - Matthew Brian Couger
- />Department of Microbiology and Molecular Genetics, Oklahoma State University, 1110 South Innovation Way, Stillwater, OK 74078 USA
| | - Rolf Prade
- />Department of Microbiology and Molecular Genetics, Oklahoma State University, 1110 South Innovation Way, Stillwater, OK 74078 USA
| | - Fabio Marcio Squina
- />Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Giuseppe Maximo Scolfaro 10.000, Campinas, São Paulo 13083-970 Brazil
| | - Aldo José Pinheiro Dillon
- />Enzymes and Biomass Laboratory, Institute of Biotechnology, University of Caxias do Sul, Francisco Getúlio Vargas Street 1130, Caxias Do Sul, RS 95070-560 Brazil
| | - Marli Camassola
- />Enzymes and Biomass Laboratory, Institute of Biotechnology, University of Caxias do Sul, Francisco Getúlio Vargas Street 1130, Caxias Do Sul, RS 95070-560 Brazil
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Couturier M, Mathieu Y, Li A, Navarro D, Drula E, Haon M, Grisel S, Ludwig R, Berrin JG. Characterization of a new aryl-alcohol oxidase secreted by the phytopathogenic fungus Ustilago maydis. Appl Microbiol Biotechnol 2015; 100:697-706. [DOI: 10.1007/s00253-015-7021-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 08/12/2015] [Accepted: 09/06/2015] [Indexed: 10/22/2022]
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Focused Directed Evolution of Aryl-Alcohol Oxidase in Saccharomyces cerevisiae by Using Chimeric Signal Peptides. Appl Environ Microbiol 2015; 81:6451-62. [PMID: 26162870 DOI: 10.1128/aem.01966-15] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Accepted: 07/03/2015] [Indexed: 01/16/2023] Open
Abstract
Aryl-alcohol oxidase (AAO) is an extracellular flavoprotein that supplies ligninolytic peroxidases with H2O2 during natural wood decay. With a broad substrate specificity and highly stereoselective reaction mechanism, AAO is an attractive candidate for studies into organic synthesis and synthetic biology, and yet the lack of suitable heterologous expression systems has precluded its engineering by directed evolution. In this study, the native signal sequence of AAO from Pleurotus eryngii was replaced by those of the mating α-factor and the K1 killer toxin, as well as different chimeras of both prepro-leaders in order to drive secretion in Saccharomyces cerevisiae. The secretion of these AAO constructs increased in the following order: preproα-AAO > preαproK-AAO > preKproα-AAO > preproK-AAO. The chimeric preαproK-AAO was subjected to focused-directed evolution with the aid of a dual screening assay based on the Fenton reaction. Random mutagenesis and DNA recombination was concentrated on two protein segments (Met[α1]-Val109 and Phe392-Gln566), and an array of improved variants was identified, among which the FX7 mutant (harboring the H91N mutation) showed a dramatic 96-fold improvement in total activity with secretion levels of 2 mg/liter. Analysis of the N-terminal sequence of the FX7 variant confirmed the correct processing of the preαproK hybrid peptide by the KEX2 protease. FX7 showed higher stability in terms of pH and temperature, whereas the pH activity profiles and the kinetic parameters were maintained. The Asn91 lies in the flavin attachment loop motif, and it is a highly conserved residue in all members of the GMC superfamily, except for P. eryngii and P. pulmonarius AAO. The in vitro involution of the enzyme by restoring the consensus ancestor Asn91 promoted AAO expression and stability.
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Zheng ZL, Qiu XH, Han RC. Identification of the Genes Involved in the Fruiting Body Production and Cordycepin Formation of Cordyceps militaris Fungus. MYCOBIOLOGY 2015; 43:37-42. [PMID: 25892913 PMCID: PMC4397378 DOI: 10.5941/myco.2015.43.1.37] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Revised: 12/10/2014] [Accepted: 02/09/2015] [Indexed: 05/11/2023]
Abstract
A mutant library of Cordyceps militaris was constructed by improved Agrobacterium tumefaciens-mediated transformation and screened for degradation features. Six mutants with altered characters in in vitro and in vivo fruiting body production, and cordycepin formation were found to contain a single copy T-DNA. T-DNA flanking sequences of these mutants were identified by thermal asymmetric interlaced-PCR approach. ATP-dependent helicase, cytochrome oxidase subunit I and ubiquitin-like activating enzyme were involved in in vitro fruiting body production, serine/threonine phosphatase involved in in vivo fruiting body production, while glucose-methanol-choline oxidoreductase and telomerase reverse transcriptase involved in cordycepin formation. These genes were analyzed by bioinformatics methods, and their molecular function and biology process were speculated by Gene Ontology (GO) analysis. The results provided useful information for the control of culture degeneration in commercial production of C. militaris.
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Affiliation(s)
- Zhuang-Li Zheng
- Guangdong Key Laboratory of Integrated Pest Management in Agriculture, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangdong Entomological Institute, Guangzhou 510260, China
| | - Xue-Hong Qiu
- Guangdong Key Laboratory of Integrated Pest Management in Agriculture, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangdong Entomological Institute, Guangzhou 510260, China
| | - Ri-Chou Han
- Guangdong Key Laboratory of Integrated Pest Management in Agriculture, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangdong Entomological Institute, Guangzhou 510260, China
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Akpinar M, Urek RO. Extracellular ligninolytic enzymes production by Pleurotus eryngii on agroindustrial wastes. Prep Biochem Biotechnol 2015; 44:772-81. [PMID: 24279903 DOI: 10.1080/10826068.2013.867870] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Pleurotus eryngii (DC.) Gillet (MCC58) was investigated for its ligninolytic ability to produce laccase (Lac), manganese peroxidase (MnP), aryl alcohol oxidase (AAO), and lignin peroxidase (LiP) enzymes through solid-state fermentation using apricot and pomegranate agroindustrial wastes. The reducing sugar, protein, lignin, and cellulose levels in these were studied. Also, the production of these ligninolytic enzymes was researched over the growth of the microorganism throughout 20 days, and the reducing sugar, protein, and nitrogen levels were recorded during the stationary cultivation at 28 ± 0.5°C. The highest Lac activity was obtained as 1618.5 ± 25 U/L on day 12 of cultivation using apricot. The highest MnP activity was attained as 570.82 ± 15 U/L on day 17 in pomegranate culture and about the same as apricot culture. There were low LiP activities in both cultures. The maximum LiP value detected was 16.13 ± 0.8 U/L in apricot cultures. In addition, AAO activities in both cultures showed similar trends up to day 17 of cultivation, with the highest AAO activity determined as 105.99 ± 6.3 U/L on day 10 in apricot cultures. Decolorization of the azo dye methyl orange was also achieved with produced ligninolytic enzymes by P. eryngii using apricot and pomegranate wastes.
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Affiliation(s)
- Merve Akpinar
- a Graduate School of Natural and Applied Sciences, Chemistry Department , Dokuz Eylül University , Buca-Izmir , Turkey
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Ferreira P, Hernández-Ortega A, Lucas F, Carro J, Herguedas B, Borrelli KW, Guallar V, Martínez AT, Medina M. Aromatic stacking interactions govern catalysis in aryl-alcohol oxidase. FEBS J 2015; 282:3091-106. [PMID: 25639975 DOI: 10.1111/febs.13221] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 01/10/2015] [Accepted: 01/28/2015] [Indexed: 01/05/2023]
Abstract
Aryl-alcohol oxidase (AAO, EC 1.1.3.7) generates H2 O2 for lignin degradation at the expense of benzylic and other π system-containing primary alcohols, which are oxidized to the corresponding aldehydes. Ligand diffusion studies on Pleurotus eryngii AAO showed a T-shaped stacking interaction between the Tyr92 side chain and the alcohol substrate at the catalytically competent position for concerted hydride and proton transfers. Bi-substrate kinetics analysis revealed that reactions with 3-chloro- or 3-fluorobenzyl alcohols (halogen substituents) proceed via a ping-pong mechanism. However, mono- and dimethoxylated substituents (in 4-methoxybenzyl and 3,4-dimethoxybenzyl alcohols) altered the mechanism and a ternary complex was formed. Electron-withdrawing substituents resulted in lower quantum mechanics stacking energies between aldehyde and the tyrosine side chain, contributing to product release, in agreement with the ping-pong mechanism observed in 3-chloro- and 3-fluorobenzyl alcohol kinetics analysis. In contrast, the higher stacking energies when electron donor substituents are present result in reaction of O2 with the flavin through a ternary complex, in agreement with the kinetics of methoxylated alcohols. The contribution of Tyr92 to the AAO reaction mechanism was investigated by calculation of stacking interaction energies and site-directed mutagenesis. Replacement of Tyr92 by phenylalanine does not alter the AAO kinetic constants (on 4-methoxybenzyl alcohol), most probably because the stacking interaction is still possible. However, introduction of a tryptophan residue at this position strongly reduced the affinity for the substrate (i.e. the pre-steady state Kd and steady-state Km increase by 150-fold and 75-fold, respectively), and therefore the steady-state catalytic efficiency, suggesting that proper stacking is impossible with this bulky residue. The above results confirm the role of Tyr92 in substrate binding, thus governing the kinetic mechanism in AAO.
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Affiliation(s)
- Patricia Ferreira
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, and Instituto de Biocomputación y Física de Sistemas Complejos, Zaragoza, Spain
| | - Aitor Hernández-Ortega
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Fátima Lucas
- Joint Barcelona Supercomputing Center-Centre for Genomic Regulation-Institute for Research in Biomedicine Research Program in Computational Biology, Barcelona Supercomputing Center, Barcelona, Spain
| | - Juan Carro
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Beatriz Herguedas
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, and Instituto de Biocomputación y Física de Sistemas Complejos, Zaragoza, Spain
| | - Kenneth W Borrelli
- Joint Barcelona Supercomputing Center-Centre for Genomic Regulation-Institute for Research in Biomedicine Research Program in Computational Biology, Barcelona Supercomputing Center, Barcelona, Spain
| | - Victor Guallar
- Joint Barcelona Supercomputing Center-Centre for Genomic Regulation-Institute for Research in Biomedicine Research Program in Computational Biology, Barcelona Supercomputing Center, Barcelona, Spain.,Institució Catalana de Recerca i Estudis Avançats, Barcelona, Spain
| | - Angel T Martínez
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Milagros Medina
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, and Instituto de Biocomputación y Física de Sistemas Complejos, Zaragoza, Spain
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28
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Carro J, Ferreira P, Rodríguez L, Prieto A, Serrano A, Balcells B, Ardá A, Jiménez‐Barbero J, Gutiérrez A, Ullrich R, Hofrichter M, Martínez AT. 5‐hydroxymethylfurfural conversion by fungal aryl‐alcohol oxidase and unspecific peroxygenase. FEBS J 2015; 282:3218-29. [DOI: 10.1111/febs.13177] [Citation(s) in RCA: 112] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 12/05/2014] [Accepted: 12/10/2014] [Indexed: 01/11/2023]
Affiliation(s)
- Juan Carro
- Centro de Investigaciones Biológicas Consejo Superior de Investigaciones Científicas Madrid Spain
| | - Patricia Ferreira
- Facultad de Ciencias and Instituto de Biocomputación y Física de Sistemas Complejos Zaragoza Spain
| | - Leonor Rodríguez
- Centro de Investigaciones Biológicas Consejo Superior de Investigaciones Científicas Madrid Spain
| | - Alicia Prieto
- Centro de Investigaciones Biológicas Consejo Superior de Investigaciones Científicas Madrid Spain
| | - Ana Serrano
- Centro de Investigaciones Biológicas Consejo Superior de Investigaciones Científicas Madrid Spain
| | - Beatriz Balcells
- Centro de Investigaciones Biológicas Consejo Superior de Investigaciones Científicas Madrid Spain
| | - Ana Ardá
- Centro de Investigaciones Biológicas Consejo Superior de Investigaciones Científicas Madrid Spain
| | - Jesús Jiménez‐Barbero
- Centro de Investigaciones Biológicas Consejo Superior de Investigaciones Científicas Madrid Spain
| | - Ana Gutiérrez
- Instituto de Recursos Naturales y Agrobiología de Sevilla Consejo Superior de Investigaciones Científicas Seville Spain
| | - René Ullrich
- Department of Bio‐ and Environmental Sciences International Institute of Zittau Germany
| | - Martin Hofrichter
- Department of Bio‐ and Environmental Sciences International Institute of Zittau Germany
| | - Angel T. Martínez
- Centro de Investigaciones Biológicas Consejo Superior de Investigaciones Científicas Madrid Spain
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29
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Fitzpatrick PF. Combining solvent isotope effects with substrate isotope effects in mechanistic studies of alcohol and amine oxidation by enzymes. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2014; 1854:1746-55. [PMID: 25448013 DOI: 10.1016/j.bbapap.2014.10.020] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 10/17/2014] [Accepted: 10/20/2014] [Indexed: 10/24/2022]
Abstract
Oxidation of alcohols and amines is catalyzed by multiple families of flavin- and pyridine nucleotide-dependent enzymes. Measurement of solvent isotope effects provides a unique mechanistic probe of the timing of the cleavage of the OH and NH bonds, necessary information for a complete description of the catalytic mechanism. The inherent ambiguities in interpretation of solvent isotope effects can be significantly decreased if isotope effects arising from isotopically labeled substrates are measured in combination with solvent isotope effects. The application of combined solvent and substrate (mainly deuterium) isotope effects to multiple enzymes is described here to illustrate the range of mechanistic insights that such an approach can provide. This article is part of a Special Issue entitled: Enzyme Transition States from Theory and Experiment.
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Affiliation(s)
- Paul F Fitzpatrick
- Department of Biochemistry, University of Texas Health Science Center, San Antonio, TX 78212, USA.
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Ferreira P, Villanueva R, Martínez-Júlvez M, Herguedas B, Marcuello C, Fernandez-Silva P, Cabon L, Hermoso JA, Lostao A, Susin SA, Medina M. Structural insights into the coenzyme mediated monomer-dimer transition of the pro-apoptotic apoptosis inducing factor. Biochemistry 2014; 53:4204-15. [PMID: 24914854 DOI: 10.1021/bi500343r] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The apoptosis-inducing factor (AIF) is a mitochondrial-flavoprotein that, after cell death induction, is distributed to the nucleus to mediate chromatinolysis. In mitochondria, AIF is present in a monomer-dimer equilibrium that after reduction by NADH gets displaced toward the dimer. The crystal structure of the human AIF (hAIF):NAD(H)-bound dimer revealed one FAD and, unexpectedly, two NAD(H) molecules per protomer. A 1:2 hAIF:NAD(H) binding stoichiometry was additionally confirmed in solution by using surface plasmon resonance. The here newly discovered NAD(H)-binding site includes residues mutated in human disorders, and accommodation of the coenzyme in it requires restructuring of a hAIF portion within the 509-560 apoptogenic segment. Disruption of interactions at the dimerization surface by production of the hAIF E413A/R422A/R430A mutant resulted in a nondimerizable variant considerably less efficiently stabilizing charge-transfer complexes upon coenzyme reduction than WT hAIF. These data reveal that the coenzyme-mediated monomer-dimer transition of hAIF modulates the conformation of its C-terminal proapoptotic domain, as well as its mechanism as reductase. These observations suggest that both the mitochondrial and apoptotic functions of hAIF are interconnected and coenzyme controlled: a key information in the understanding of the physiological role of AIF in the cellular life and death cycle.
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Affiliation(s)
- Patricia Ferreira
- Departamento de Bioquímica y Biología Molecular y Celular, ‡Instituto de Biocomputación y Física de Sistemas Complejos (BIFI)-Joint Unit BIFI-IQFR (CSIC), and §Laboratorio de Microscopias Avanzadas, Instituto de Nanociencia de Aragón (INA), Universidad de Zaragoza , Zaragoza, Spain
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31
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Chakraborty M, Goel M, Chinnadayyala SR, Dahiya UR, Ghosh SS, Goswami P. Molecular characterization and expression of a novel alcohol oxidase from Aspergillus terreus MTCC6324. PLoS One 2014; 9:e95368. [PMID: 24752075 PMCID: PMC3994049 DOI: 10.1371/journal.pone.0095368] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 03/26/2014] [Indexed: 11/28/2022] Open
Abstract
The alcohol oxidase (AOx) cDNA from Aspergillus terreus MTCC6324 with an open reading frame (ORF) of 2001 bp was constructed from n-hexadecane induced cells and expressed in Escherichia coli with a yield of ∼4.2 mg protein g−1 wet cell. The deduced amino acid sequences of recombinant rAOx showed maximum structural homology with the chain B of aryl AOx from Pleurotus eryngii. A functionally active AOx was achieved by incubating the apo-AOx with flavin adenine dinucleotide (FAD) for ∼80 h at 16°C and pH 9.0. The isoelectric point and mass of the apo-AOx were found to be 6.5±0.1 and ∼74 kDa, respectively. Circular dichroism data of the rAOx confirmed its ordered structure. Docking studies with an ab-initio protein model demonstrated the presence of a conserved FAD binding domain with an active substrate binding site. The rAOx was specific for aryl alcohols and the order of its substrate preference was 4-methoxybenzyl alcohol >3-methoxybenzyl alcohol>3, 4-dimethoxybenzyl alcohol > benzyl alcohol. A significantly high aggregation to ∼1000 nm (diameter) and catalytic efficiency (kcat/Km) of 7829.5 min−1 mM−1 for 4-methoxybenzyl alcohol was also demonstrated for rAOx. The results infer the novelty of the AOx and its potential biocatalytic application.
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Affiliation(s)
- Mitun Chakraborty
- Department of Biotechnology, Indian Institute of Technology Guwahati, Assam, India
| | - Manish Goel
- Department of Biotechnology, Indian Institute of Technology Guwahati, Assam, India
| | | | - Ujjwal Ranjan Dahiya
- Department of Biotechnology, Indian Institute of Technology Guwahati, Assam, India
| | - Siddhartha Sankar Ghosh
- Department of Biotechnology, Indian Institute of Technology Guwahati, Assam, India
- * E-mail: (SSG); (PG)
| | - Pranab Goswami
- Department of Biotechnology, Indian Institute of Technology Guwahati, Assam, India
- * E-mail: (SSG); (PG)
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Meinhardt LW, Costa GGL, Thomazella DPT, Teixeira PJPL, Carazzolle MF, Schuster SC, Carlson JE, Guiltinan MJ, Mieczkowski P, Farmer A, Ramaraj T, Crozier J, Davis RE, Shao J, Melnick RL, Pereira GAG, Bailey BA. Genome and secretome analysis of the hemibiotrophic fungal pathogen, Moniliophthora roreri, which causes frosty pod rot disease of cacao: mechanisms of the biotrophic and necrotrophic phases. BMC Genomics 2014; 15:164. [PMID: 24571091 PMCID: PMC3948071 DOI: 10.1186/1471-2164-15-164] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2013] [Accepted: 02/14/2014] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND The basidiomycete Moniliophthora roreri is the causal agent of Frosty pod rot (FPR) disease of cacao (Theobroma cacao), the source of chocolate, and FPR is one of the most destructive diseases of this important perennial crop in the Americas. This hemibiotroph infects only cacao pods and has an extended biotrophic phase lasting up to sixty days, culminating in plant necrosis and sporulation of the fungus without the formation of a basidiocarp. RESULTS We sequenced and assembled 52.3 Mb into 3,298 contigs that represent the M. roreri genome. Of the 17,920 predicted open reading frames (OFRs), 13,760 were validated by RNA-Seq. Using read count data from RNA sequencing of cacao pods at 30 and 60 days post infection, differential gene expression was estimated for the biotrophic and necrotrophic phases of this plant-pathogen interaction. The sequencing data were used to develop a genome based secretome for the infected pods. Of the 1,535 genes encoding putative secreted proteins, 1,355 were expressed in the biotrophic and necrotrophic phases. Analysis of the data revealed secretome gene expression that correlated with infection and intercellular growth in the biotrophic phase and invasive growth and plant cellular death in the necrotrophic phase. CONCLUSIONS Genome sequencing and RNA-Seq was used to determine and validate the Moniliophthora roreri genome and secretome. High sequence identity between Moniliophthora roreri genes and Moniliophthora perniciosa genes supports the taxonomic relationship with Moniliophthora perniciosa and the relatedness of this fungus to other basidiomycetes. Analysis of RNA-Seq data from infected plant tissues revealed differentially expressed genes in the biotrophic and necrotrophic phases. The secreted protein genes that were upregulated in the biotrophic phase are primarily associated with breakdown of the intercellular matrix and modification of the fungal mycelia, possibly to mask the fungus from plant defenses. Based on the transcriptome data, the upregulated secreted proteins in the necrotrophic phase are hypothesized to be actively attacking the plant cell walls and plant cellular components resulting in necrosis. These genes are being used to develop a new understanding of how this disease interaction progresses and to identify potential targets to reduce the impact of this devastating disease.
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Affiliation(s)
- Lyndel W Meinhardt
- Sustainable Perennial Crops Lab, USDA/ARS, Bldg 001 Rm 223 Beltsville Agricultural Research Center-West, Beltsville, MD 20705, USA
| | - Gustavo Gilson Lacerda Costa
- Centro Nacional de Processamento de Alto Desempenho em São Paulo, Universidade Estadual de Campinas, CP 6141, Campinas 13083-970, SP, Brazil
| | - Daniela PT Thomazella
- Laboratório de Genômica e Expressão, Departamento de Genética, Evolução e Bioagentes, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), CP 6109, Campinas 13083-970, SP, Brazil
| | - Paulo José PL Teixeira
- Laboratório de Genômica e Expressão, Departamento de Genética, Evolução e Bioagentes, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), CP 6109, Campinas 13083-970, SP, Brazil
| | - Marcelo Falsarella Carazzolle
- Centro Nacional de Processamento de Alto Desempenho em São Paulo, Universidade Estadual de Campinas, CP 6141, Campinas 13083-970, SP, Brazil
| | - Stephan C Schuster
- Center for Infectious Disease Dynamics, Pennsylvania State University, University Park, PA 16802, USA
| | - John E Carlson
- Department of Ecosystem Science and Management, Pennsylvania State University, University Park, PA 16802, USA
| | - Mark J Guiltinan
- Department of Horticulture, Pennsylvania State University, University Park, PA 16802, USA
| | - Piotr Mieczkowski
- Department of Genetics, School of Medicine, University of North Carolina at Chapel Hill, Mary Ellen Jones, Room 921, 27599-3280 Chapel Hill, NC, USA
| | - Andrew Farmer
- National Center of Genomic Research, 2935 Rodeo Park Drive East Santa Fe, NM 87505 Santa Fe, USA
| | - Thiruvarangan Ramaraj
- National Center of Genomic Research, 2935 Rodeo Park Drive East Santa Fe, NM 87505 Santa Fe, USA
| | | | - Robert E Davis
- Molecular Plant Pathology Lab, USDA/ARS, Bldg 004 Rm 119 Beltsville Agricultural Research Center West, Beltsville, MD 20705, USA
| | - Jonathan Shao
- Molecular Plant Pathology Lab, USDA/ARS, Bldg 004 Rm 119 Beltsville Agricultural Research Center West, Beltsville, MD 20705, USA
| | - Rachel L Melnick
- Sustainable Perennial Crops Lab, USDA/ARS, Bldg 001 Rm 223 Beltsville Agricultural Research Center-West, Beltsville, MD 20705, USA
| | - Gonçalo AG Pereira
- Laboratório de Genômica e Expressão, Departamento de Genética, Evolução e Bioagentes, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), CP 6109, Campinas 13083-970, SP, Brazil
| | - Bryan A Bailey
- Sustainable Perennial Crops Lab, USDA/ARS, Bldg 001 Rm 223 Beltsville Agricultural Research Center-West, Beltsville, MD 20705, USA
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Wongnate T, Chaiyen P. The substrate oxidation mechanism of pyranose 2-oxidase and other related enzymes in the glucose-methanol-choline superfamily. FEBS J 2013; 280:3009-27. [DOI: 10.1111/febs.12280] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2013] [Revised: 04/01/2013] [Accepted: 04/04/2013] [Indexed: 01/13/2023]
Affiliation(s)
- Thanyaporn Wongnate
- Department of Biochemistry and Center of Excellence in Protein Structure and Function, Faculty of Science; Mahidol University; Bangkok; Thailand
| | - Pimchai Chaiyen
- Department of Biochemistry and Center of Excellence in Protein Structure and Function, Faculty of Science; Mahidol University; Bangkok; Thailand
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Yakovlev IA, Hietala AM, Courty PE, Lundell T, Solheim H, Fossdal CG. Genes associated with lignin degradation in the polyphagous white-rot pathogen Heterobasidion irregulare show substrate-specific regulation. Fungal Genet Biol 2013; 56:17-24. [PMID: 23665189 DOI: 10.1016/j.fgb.2013.04.011] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Revised: 04/26/2013] [Accepted: 04/29/2013] [Indexed: 11/15/2022]
Abstract
The pathogenic white-rot basidiomycete Heterobasidion irregulare is able to remove lignin and hemicellulose prior to cellulose during the colonization of root and stem xylem of conifer and broadleaf trees. We identified and followed the regulation of expression of genes belonging to families encoding ligninolytic enzymes. In comparison with typical white-rot fungi, the H. irregulare genome has exclusively the short-manganese peroxidase type encoding genes (6 short-MnPs) and thereby a slight contraction in the pool of class II heme-containing peroxidases, but an expansion of the MCO laccases with 17 gene models. Furthermore, the genome shows a versatile set of other oxidoreductase genes putatively involved in lignin oxidation and conversion, including 5 glyoxal oxidases, 19 quinone-oxidoreductases and 12 aryl-alcohol oxidases. Their genetic multiplicity and gene-specific regulation patterns on cultures based on defined lignin, cellulose or Norway spruce lignocellulose substrates suggest divergent specificities and physiological roles for these enzymes. While the short-MnP encoding genes showed similar transcript levels upon fungal growth on heartwood and reaction zone (RZ), a xylem defense tissue rich in phenolic compounds unique to trees, a subset of laccases showed higher gene expression in the RZ cultures. In contrast, other oxidoreductases depending on initial MnP activity showed generally lower transcript levels on RZ than on heartwood. These data suggest that the rate of fungal oxidative conversion of xylem lignin differs between spruce RZ and heartwood. It is conceivable that in RZ part of the oxidoreductase activities of laccases are related to the detoxification of phenolic compounds involved in host-defense. Expression of the several short-MnP enzymes indicated an important role for these enzymes in effective delignification of wood by H. irregulare.
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Affiliation(s)
- Igor A Yakovlev
- Norwegian Forest and Landscape Institute, PO Box 115, N-1431 Ås, Norway
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35
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An overview on alcohol oxidases and their potential applications. Appl Microbiol Biotechnol 2013; 97:4259-75. [DOI: 10.1007/s00253-013-4842-9] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Revised: 03/06/2013] [Accepted: 03/07/2013] [Indexed: 10/27/2022]
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Akpinar M, Urek RO. Production of ligninolytic enzymes by solid-state fermentation using Pleurotus eryngii. Prep Biochem Biotechnol 2013; 42:582-97. [PMID: 23030469 DOI: 10.1080/10826068.2012.673528] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Pleurotus eryngii (DC.) Gillet (MCC58) was investigated for its ability to produce various ligninolytic enzymes such as laccase (Lac), manganese peroxidase (MnP), aryl alcohol oxidase (AAO), and lignin peroxidase (LiP) by solid-state fermentation (SSF), which was carried out using a support substrate from the fruit juice industry. The chemical content of grape waste from this industry was studied. Also, the production patterns of these extracellular enzymes were researched during the growth of the organism for a period of 20 days and the protein, reducing sugar, and nitrogen levels were monitored during the stationary cultivation. The highest Lac activity was obtained as 2247.62 ± 75 U/L on day 10 in the presence of 750 µM Mn²⁺, while the highest MnP activity was attained as 2198.44 ± 65 U/L on day 15 in the presence of 500 µM Mn²⁺. Decolorization of methyl orange and reactive red 2 azo dyes was also achieved with ligninolytic enzymes, produced in SSF of P. eryngii.
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Affiliation(s)
- Merve Akpinar
- Chemistry Department, Graduate School of Natural and Applied Sciences, Dokuz Eylul University, Izmir, Turkey
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37
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Hernández-Ortega A, Lucas F, Ferreira P, Medina M, Guallar V, Martínez AT. Role of Active Site Histidines in the Two Half-Reactions of the Aryl-Alcohol Oxidase Catalytic Cycle. Biochemistry 2012; 51:6595-608. [DOI: 10.1021/bi300505z] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Fátima Lucas
- Joint BSC-IRB
Research Program
in Computational Biology, Barcelona Supercomputing Center, Jordi Girona 29, E-08034 Barcelona, Spain
| | - Patricia Ferreira
- Department of Biochemistry and
Molecular and Cellular Biology and Institute of Biocomputation and
Physics of Complex Systems, University of Zaragoza, E-50009 Zaragoza, Spain
| | - Milagros Medina
- Department of Biochemistry and
Molecular and Cellular Biology and Institute of Biocomputation and
Physics of Complex Systems, University of Zaragoza, E-50009 Zaragoza, Spain
| | - Victor Guallar
- Joint BSC-IRB
Research Program
in Computational Biology, Barcelona Supercomputing Center, Jordi Girona 29, E-08034 Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Passeig Lluís Companys 23, E-08010 Barcelona, Spain
| | - Angel T. Martínez
- Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, E-28040
Madrid, Spain
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Zorn H, Lauber C, Lorenz P, Schüttmann I, Rühl M. Entwicklung eines Zwei-Enzym-Systems aus einer Peroxidase und einer Arylalkoholoxidase zum Aufschluss von Lignocellulosen. CHEM-ING-TECH 2012. [DOI: 10.1002/cite.201250513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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39
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Etxebeste O, Herrero-García E, Cortese MS, Garzia A, Oiartzabal-Arano E, de los Ríos V, Ugalde U, Espeso EA. GmcA is a putative glucose-methanol-choline oxidoreductase required for the induction of asexual development in Aspergillus nidulans. PLoS One 2012; 7:e40292. [PMID: 22792266 PMCID: PMC3390393 DOI: 10.1371/journal.pone.0040292] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Accepted: 06/05/2012] [Indexed: 11/18/2022] Open
Abstract
Aspergillus nidulans asexual differentiation is induced by Upstream Developmental Activators (UDAs) that include the bZIP-type Transcription Factor (TF) FlbB. A 2D-PAGE/MS-MS-coupled screen for proteins differentially expressed in the presence and absence of FlbB identified 18 candidates. Most candidates belong to GO term classes involved in osmotic and/or oxidative stress response. Among these, we focused on GmcA, a putative glucose-methanol-choline oxidoreductase which is upregulated in a ΔflbB background. GmcA is not required for growth since no differences were detected in the radial extension upon deletion of gmcA. However, its activity is required to induce conidiation under specific culture conditions. A ΔgmcA strain conidiates profusely under acid conditions but displays a characteristic fluffy aconidial phenotype in alkaline medium. The absence of asexual development in a ΔgmcA strain can be suppressed, on one hand, using high concentrations of non-fermentable carbon sources like glycerol, and on the other hand, when the cMyb-type UDA TF flbD is overexpressed. Overall, the results obtained in this work support a role for GmcA at early stages of conidiophore initiation.
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Affiliation(s)
- Oier Etxebeste
- Department of Applied Chemistry, Faculty of Chemistry, University of The Basque Country, Manuel de Lardizabal, San Sebastian, Spain.
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40
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Hernández-Ortega A, Ferreira P, Merino P, Medina M, Guallar V, Martínez AT. Stereoselective Hydride Transfer by Aryl-Alcohol Oxidase, a Member of the GMC Superfamily. Chembiochem 2012; 13:427-35. [PMID: 22271643 DOI: 10.1002/cbic.201100709] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2011] [Indexed: 11/06/2022]
Affiliation(s)
- Aitor Hernández-Ortega
- Centro de Investigaciones Biológicas (CIB), Consejo Superior de Investigaciones Científicas (CSIC), Ramiro de Maeztu 9, 28040 Madrid, Spain
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Fungal aryl-alcohol oxidase: a peroxide-producing flavoenzyme involved in lignin degradation. Appl Microbiol Biotechnol 2012; 93:1395-410. [DOI: 10.1007/s00253-011-3836-8] [Citation(s) in RCA: 121] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2011] [Revised: 12/06/2011] [Accepted: 12/09/2011] [Indexed: 11/30/2022]
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Hernández-Ortega A, Lucas F, Ferreira P, Medina M, Guallar V, Martínez AT. Modulating O2 reactivity in a fungal flavoenzyme: involvement of aryl-alcohol oxidase Phe-501 contiguous to catalytic histidine. J Biol Chem 2011; 286:41105-14. [PMID: 21940622 DOI: 10.1074/jbc.m111.282467] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Aryl-alcohol oxidase (AAO) is a flavoenzyme responsible for activation of O(2) to H(2)O(2) in fungal degradation of lignin. The AAO crystal structure shows a buried active site connected to the solvent by a hydrophobic funnel-shaped channel, with Phe-501 and two other aromatic residues forming a narrow bottleneck that prevents the direct access of alcohol substrates. However, ligand diffusion simulations show O(2) access to the active site following this channel. Site-directed mutagenesis of Phe-501 yielded a F501A variant with strongly reduced O(2) reactivity. However, a variant with increased reactivity, as shown by kinetic constants and steady-state oxidation degree, was obtained by substitution of Phe-501 with tryptophan. The high oxygen catalytic efficiency of F501W, ∼2-fold that of native AAO and ∼120-fold that of F501A, seems related to a higher O(2) availability because the turnover number was slightly decreased with respect to the native enzyme. Free diffusion simulations of O(2) inside the active-site cavity of AAO (and several in silico Phe-501 variants) yielded >60% O(2) population at 3-4 Å from flavin C4a in F501W compared with 44% in AAO and only 14% in F501A. Paradoxically, the O(2) reactivity of AAO decreased when the access channel was enlarged and increased when it was constricted by introducing a tryptophan residue. This is because the side chain of Phe-501, contiguous to the catalytic histidine (His-502 in AAO), helps to position O(2) at an adequate distance from flavin C4a (and His-502 Nε). Phe-501 substitution with a bulkier tryptophan residue resulted in an increase in the O(2) reactivity of this flavoenzyme.
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Affiliation(s)
- Aitor Hernández-Ortega
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu 9, E-28040 Madrid, Spain
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Substrate diffusion and oxidation in GMC oxidoreductases: an experimental and computational study on fungal aryl-alcohol oxidase. Biochem J 2011; 436:341-50. [DOI: 10.1042/bj20102090] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
AAO (aryl-alcohol oxidase) provides H2O2 in fungal degradation of lignin, a process of high biotechnological interest. The crystal structure of AAO does not show open access to the active site, where different aromatic alcohols are oxidized. In the present study we investigated substrate diffusion and oxidation in AAO compared with the structurally related CHO (choline oxidase). Cavity finder and ligand diffusion simulations indicate the substrate-entrance channel, requiring side-chain displacements and involving a stacking interaction with Tyr92. Mixed QM (quantum mechanics)/MM (molecular mechanics) studies combined with site-directed mutagenesis showed two active-site catalytic histidine residues, whose substitution strongly decreased both catalytic and transient-state reduction constants for p-anisyl alcohol in the H502A (over 1800-fold) and H546A (over 35-fold) variants. Combination of QM/MM energy profiles, protonation predictors, molecular dynamics, mutagenesis and pH profiles provide a robust answer regarding the nature of the catalytic base. The histidine residue in front of the FAD ring, AAO His502 (and CHO His466), acts as a base. For the two substrates assayed, it was shown that proton transfer preceded hydride transfer, although both processes are highly coupled. No stable intermediate was observed in the energy profiles, in contrast with that observed for CHO. QM/MM, together with solvent KIE (kinetic isotope effect) results, suggest a non-synchronous concerted mechanism for alcohol oxidation by AAO.
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Lundell TK, Mäkelä MR, Hildén K. Lignin-modifying enzymes in filamentous basidiomycetes--ecological, functional and phylogenetic review. J Basic Microbiol 2010; 50:5-20. [PMID: 20175122 DOI: 10.1002/jobm.200900338] [Citation(s) in RCA: 216] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Filamentous fungi owe powerful abilities for decomposition of the extensive plant material, lignocellulose, and thereby are indispensable for the Earth's carbon cycle, generation of soil humic matter and formation of soil fine structure. The filamentous wood-decaying fungi belong to the phyla Basidiomycota and Ascomycota, and are unique organisms specified to degradation of the xylem cell wall components (cellulose, hemicelluloses, lignins and extractives). The basidiomycetous wood-decaying fungi form brackets, caps or resupinaceous (corticioid) fruiting bodies when growing on wood for dissemination of their sexual basidiospores. In particular, the ability to decompose the aromatic lignin polymers in wood is mostly restricted to the white rot basidiomycetes. The white-rot decay of wood is possible due to secretion of organic acids, secondary metabolites, and oxidoreductive metalloenzymes, heme peroxidases and laccases, encoded by divergent gene families in these fungi. The brown rot basidiomycetes obviously depend more on a non-enzymatic strategy for decomposition of wood cellulose and modification of lignin. This review gives a current ecological, genomic, and protein functional and phylogenetic perspective of the wood and lignocellulose-decaying basidiomycetous fungi.
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Affiliation(s)
- Taina K Lundell
- Fungal Biotechnology Group, Department of Applied Chemistry and Microbiology, Division of Microbiology, Viikki Biocenter, University of Helsinki, Finland.
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Kinetic and chemical characterization of aldehyde oxidation by fungal aryl-alcohol oxidase. Biochem J 2010; 425:585-93. [PMID: 19891608 DOI: 10.1042/bj20091499] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Fungal AAO (aryl-alcohol oxidase) provides H2O2 for lignin biodegradation. AAO is active on benzyl alcohols that are oxidized to aldehydes. However, during oxidation of some alcohols, AAO forms more than a stoichiometric number of H2O2 molecules with respect to the amount of aldehyde detected due to a double reaction that involves aryl-aldehyde oxidase activity. The latter reaction was investigated using different benzylic aldehydes, whose oxidation to acids was demonstrated by GC-MS. The steady- and presteady state kinetic constants, together with the chromatographic results, revealed that the presence of substrate electron-withdrawing or electron-donating substituents had a strong influence on activity; the highest activity was with p-nitrobenzaldehyde and halogenated aldehydes and the lowest with methoxylated aldehydes. Moreover, activity was correlated to the aldehyde hydration rates estimated by 1H-NMR. These findings, together with the absence in the AAO active site of a residue able to drive oxidation via an aldehyde thiohemiacetal, suggested that oxidation mainly proceeds via the gem-diol species. The reaction mechanism (with a solvent isotope effect, 2H2Okred, of approx. 1.5) would be analogous to that described for alcohols, the reductive half-reaction involving concerted hydride transfer from the alpha-carbon and proton abstraction from one of the gem-diol hydroxy groups by a base. The existence of two steps of opposite polar requirements (hydration and hydride transfer) explains some aspects of aldehyde oxidation by AAO. Site-directed mutagenesis identified two histidine residues strongly involved in gem-diol oxidation and, unexpectedly, suggested that an active-site tyrosine residue could facilitate the oxidation of some aldehydes that show no detectable hydration. Double alcohol and aldehyde oxidase activities of AAO would contribute to H2O2 supply by the enzyme.
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