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Zhou H, Cai Y, Long M, Zheng N, Zhang Z, You C, Hussain A, Xia X. Computer-Aided Reconstruction and Application of Bacillus halodurans S7 Xylanase with Heat and Alkali Resistance. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:1213-1227. [PMID: 38183306 DOI: 10.1021/acs.jafc.3c08221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2024]
Abstract
β-1,4-Endoxylanase is the most critical hydrolase for xylan degradation during lignocellulosic biomass utilization. However, its poor stability and activity in hot and alkaline environments hinder its widespread application. In this study, BhS7Xyl from Bacillus halodurans S7 was improved using a computer-aided design through isothermal compressibility (βT) perturbation engineering and by combining three thermostability prediction algorithms (ICPE-TPA). The best variant with remarkable improvement in specific activity, heat resistance (70 °C), and alkaline resistance (both pH 9.0 and 70 °C), R69F/E137M/E145L, exhibited a 4.9-fold increase by wild-type in specific activity (1368.6 U/mg), a 39.4-fold increase in temperature half-life (458.1 min), and a 57.6-fold increase in pH half-life (383.1 min). Furthermore, R69F/E137M/E145L was applied to the hydrolysis of agricultural waste (corncob and hardwood pulp) to efficiently obtain a higher yield of high-value xylooligosaccharides. Overall, the ICPE-TPA strategy has the potential to improve the functional performance of enzymes under extreme conditions for the high-value utilization of lignocellulosic biomass.
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Affiliation(s)
- Huimin Zhou
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Yongchao Cai
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Mengfei Long
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Nan Zheng
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Zehua Zhang
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Cuiping You
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Asif Hussain
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Xiaole Xia
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
- College of Food Science and Engineering, Tianjin University of Science & Technology, Tianjin 300000, China
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2
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García-Cebollada H, López A, Sancho J. Protposer: the web server that readily proposes protein stabilizing mutations with high PPV. Comput Struct Biotechnol J 2022; 20:2415-2433. [PMID: 35664235 PMCID: PMC9133766 DOI: 10.1016/j.csbj.2022.05.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 05/05/2022] [Accepted: 05/05/2022] [Indexed: 01/23/2023] Open
Abstract
Protein stability is a requisite for most biotechnological and medical applications of proteins. As natural proteins tend to suffer from a low conformational stability ex vivo, great efforts have been devoted toward increasing their stability through rational design and engineering of appropriate mutations. Unfortunately, even the best currently used predictors fail to compute the stability of protein variants with sufficient accuracy and their usefulness as tools to guide the rational stabilisation of proteins is limited. We present here Protposer, a protein stabilising tool based on a different approach. Instead of quantifying changes in stability, Protposer uses structure- and sequence-based screening modules to nominate candidate mutations for subsequent evaluation by a logistic regression model, carefully trained to avoid overfitting. Thus, Protposer analyses PDB files in search for stabilization opportunities and provides a ranked list of promising mutations with their estimated success rates (eSR), their probabilities of being stabilising by at least 0.5 kcal/mol. The agreement between eSRs and actual positive predictive values (PPV) on external datasets of mutations is excellent. When Protposer is used with its Optimal kappa selection threshold, its PPV is above 0.7. Even with less stringent thresholds, Protposer largely outperforms FoldX, Rosetta and PoPMusiC. Indicating the PDB file of the protein suffices to obtain a ranked list of mutations, their eSRs and hints on the likely source of the stabilization expected. Protposer is a distinct, straightforward and highly successful tool to design protein stabilising mutations, and it is freely available for academic use at http://webapps.bifi.es/the-protposer.
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Staritzbichler R, Ristic N, Goede A, Preissner R, Hildebrand PW. Voronoia 4-ever. Nucleic Acids Res 2021; 49:W685-W690. [PMID: 34107038 PMCID: PMC8265189 DOI: 10.1093/nar/gkab466] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 05/07/2021] [Accepted: 06/07/2021] [Indexed: 11/12/2022] Open
Abstract
We present an updated version of the Voronoia service that enables fully automated analysis of the atomic packing density of macromolecules. Voronoia combines previous efforts to analyse 3D protein and RNA structures into a single service, combined with state-of-the-art online visualization. Voronoia uses the Voronoi cell method to calculate the free space between neighbouring atoms to estimate van der Waals interactions. Compared to other methods that derive van der Waals interactions by calculating solvent-free surfaces, it explicitly considers volume or packing defects. Large internal voids refer either to water molecules or ions unresolved by X-ray crystallography or cryo-EM, cryptic ligand binding pockets, or parts of a structural model that require further refinement. Voronoia is, therefore mainly used for functional analyses of 3D structures and quality assessments of structural models. Voronoia 4-ever updates the database of precomputed packing densities of PDB entries, allows uploading multiple structures, adds new filter options and facilitates direct access to the results through intuitive display with the NGL viewer. Voronoia is available at: htttp://proteinformatics.org/voronoia.
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Affiliation(s)
- Rene Staritzbichler
- University of Leipzig, Institute of Medical Physics and Biophysics, Leipzig, Germany
| | - Nikola Ristic
- University of Leipzig, Institute of Medical Physics and Biophysics, Leipzig, Germany
| | - Andrean Goede
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Physiology, Structural Bioinformatics Group, Berlin 10117, Germany
| | - Robert Preissner
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Physiology, Structural Bioinformatics Group, Berlin 10117, Germany.,Charité -Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Information Technology, Science IT, Charitéplatz 1, 10117 Berlin, Germany
| | - Peter W Hildebrand
- University of Leipzig, Institute of Medical Physics and Biophysics, Leipzig, Germany.,Charité -Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Medical Physics and Biophysics, Charitéplatz 1, 10117 Berlin, Germany.,Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
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Chae H, Cho S, Jeong M, Kwon K, Choi D, Lee J, Nam W, Hong J, Lee J, Yoon S, Hong H. Improvement of Biophysical Properties and Affinity of a Human Anti-L1CAM Therapeutic Antibody through Antibody Engineering Based on Computational Methods. Int J Mol Sci 2021; 22:ijms22136696. [PMID: 34206616 PMCID: PMC8268072 DOI: 10.3390/ijms22136696] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 06/18/2021] [Accepted: 06/19/2021] [Indexed: 01/14/2023] Open
Abstract
The biophysical properties of therapeutic antibodies influence their manufacturability, efficacy, and safety. To develop an anti-cancer antibody, we previously generated a human monoclonal antibody (Ab417) that specifically binds to L1 cell adhesion molecule with a high affinity, and we validated its anti-tumor activity and mechanism of action in human cholangiocarcinoma xenograft models. In the present study, we aimed to improve the biophysical properties of Ab417. We designed 20 variants of Ab417 with reduced aggregation propensity, less potential post-translational modification (PTM) motifs, and the lowest predicted immunogenicity using computational methods. Next, we constructed these variants to analyze their expression levels and antigen-binding activities. One variant (Ab612)—which contains six substitutions for reduced surface hydrophobicity, removal of PTM, and change to the germline residue—exhibited an increased expression level and antigen-binding activity compared to Ab417. In further studies, compared to Ab417, Ab612 showed improved biophysical properties, including reduced aggregation propensity, increased stability, higher purification yield, lower pI, higher affinity, and greater in vivo anti-tumor efficacy. Additionally, we generated a highly productive and stable research cell bank (RCB) and scaled up the production process to 50 L, yielding 6.6 g/L of Ab612. The RCB will be used for preclinical development of Ab612.
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Affiliation(s)
- Heesu Chae
- Department of Systems Immunology, Kangwon National University, Chuncheon 24341, Korea; (H.C.); (M.J.); (K.K.); (J.H.); (J.L.)
- APIT BIO Inc., B910, Munjeongdong Tera Tower, 167 Songpa-daero, Songpa-gu, Seoul 05855, Korea; (J.L.); (W.N.)
| | - Seulki Cho
- Institute of Bioscience and Biotechnology, Kangwon National University, Chuncheon 24341, Korea;
| | - Munsik Jeong
- Department of Systems Immunology, Kangwon National University, Chuncheon 24341, Korea; (H.C.); (M.J.); (K.K.); (J.H.); (J.L.)
| | - Kiyoung Kwon
- Department of Systems Immunology, Kangwon National University, Chuncheon 24341, Korea; (H.C.); (M.J.); (K.K.); (J.H.); (J.L.)
| | - Dongwook Choi
- Division of Drug Process Development, New Drug Development Center, Osong Medical Innovation Foundation, Chungcheongbuk-do, Cheongju-si 28160, Korea;
| | - Jaeyoung Lee
- APIT BIO Inc., B910, Munjeongdong Tera Tower, 167 Songpa-daero, Songpa-gu, Seoul 05855, Korea; (J.L.); (W.N.)
| | - Woosuk Nam
- APIT BIO Inc., B910, Munjeongdong Tera Tower, 167 Songpa-daero, Songpa-gu, Seoul 05855, Korea; (J.L.); (W.N.)
| | - Jisu Hong
- Department of Systems Immunology, Kangwon National University, Chuncheon 24341, Korea; (H.C.); (M.J.); (K.K.); (J.H.); (J.L.)
| | - Jiwoo Lee
- Department of Systems Immunology, Kangwon National University, Chuncheon 24341, Korea; (H.C.); (M.J.); (K.K.); (J.H.); (J.L.)
| | - Seonjoo Yoon
- APIT BIO Inc., B910, Munjeongdong Tera Tower, 167 Songpa-daero, Songpa-gu, Seoul 05855, Korea; (J.L.); (W.N.)
- Correspondence: (S.Y.); (H.H.); Tel.: +82-10-2305-9704 (S.Y.); +82-10-5430-0480 (H.H.)
| | - Hyojeong Hong
- Department of Systems Immunology, Kangwon National University, Chuncheon 24341, Korea; (H.C.); (M.J.); (K.K.); (J.H.); (J.L.)
- Institute of Bioscience and Biotechnology, Kangwon National University, Chuncheon 24341, Korea;
- Correspondence: (S.Y.); (H.H.); Tel.: +82-10-2305-9704 (S.Y.); +82-10-5430-0480 (H.H.)
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The state-of-play and future of antibody therapeutics. Adv Drug Deliv Rev 2017; 122:2-19. [PMID: 27916504 DOI: 10.1016/j.addr.2016.11.004] [Citation(s) in RCA: 185] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 11/26/2016] [Accepted: 11/28/2016] [Indexed: 12/22/2022]
Abstract
It has been over four decades since the development of monoclonal antibodies (mAbs) using a hybridoma cell line was first reported. Since then more than thirty therapeutic antibodies have been marketed, mostly as oncology, autoimmune and inflammatory therapeutics. While antibodies are very efficient, their cost-effectiveness has always been discussed owing to their high costs, accumulating to more than one billion dollars from preclinical development through to market approval. Because of this, therapeutic antibodies are inaccessible to some patients in both developed and developing countries. The growing interest in biosimilar antibodies as affordable versions of therapeutic antibodies may provide alternative treatment options as well potentially decreasing costs. As certain markets begin to capitalize on this opportunity, regulatory authorities continue to refine the requirements for demonstrating quality, efficacy and safety of biosimilar compared to originator products. In addition to biosimilars, innovations in antibody engineering are providing the opportunity to design biobetter antibodies with improved properties to maximize efficacy. Enhancing effector function, antibody drug conjugates (ADC) or targeting multiple disease pathways via multi-specific antibodies are being explored. The manufacturing process of antibodies is also moving forward with advancements relating to host cell production and purification processes. Studies into the physical and chemical degradation pathways of antibodies are contributing to the design of more stable proteins guided by computational tools. Moreover, the delivery and pharmacokinetics of antibody-based therapeutics are improving as optimized formulations are pursued through the implementation of recent innovations in the field.
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Membrane proteins structures: A review on computational modeling tools. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1859:2021-2039. [DOI: 10.1016/j.bbamem.2017.07.008] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 07/04/2017] [Accepted: 07/13/2017] [Indexed: 01/02/2023]
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Chakroun N, Hilton D, Ahmad SS, Platt GW, Dalby PA. Mapping the Aggregation Kinetics of a Therapeutic Antibody Fragment. Mol Pharm 2016; 13:307-19. [PMID: 26692229 DOI: 10.1021/acs.molpharmaceut.5b00387] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The analytical characterization of biopharmaceuticals is a fundamental step in the early stages of development and prediction of their behavior in bioprocesses. Protein aggregation in particular is a common issue as it affects all stages of product development. In the present work, we investigate the stability and the aggregation kinetics of A33Fab, a therapeutically relevant humanized antibody fragment at a wide range of pH, ionic strength, and temperature. We show that the propensity of A33Fab to aggregate under thermally accelerated conditions is pH and ionic-strength dependent with a stronger destabilizing effect of ionic strength at low pH. In the absence of added salts, A33Fab molecules appear to be protected from aggregation due to electrostatic colloidal repulsion at low pH. Analysis by transmission electron microscopy identified significantly different aggregate species formed at low and high pH. The correlations between apparent midpoints of thermal transitions (Tm,app values), or unfolded mole fractions, and aggregation rates are reported here to be significant only at the elevated incubation temperature of 65 °C, where aggregation from the unfolded state predominates. At all other conditions, particularly at 4-45 °C, aggregation of A33 Fab was predominantly from a native-like state, and the kinetics obeyed Arrhenius behavior. Despite this, the rank order of aggregation rates observed at 45 °C, 23 and 4 °C still did not correlate well to each other, indicating that forced degradation at elevated temperatures was not a good screen for predicting behavior at low temperature.
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Affiliation(s)
- Nesrine Chakroun
- EPSRC Centre for Innovative Manufacturing in Emergent Macromolecular Therapies, Department of Biochemical Engineering, University College London , London WC1H 0AH, U.K.,Department of Biochemical Engineering, University College London , London WC1H 0AH, U.K
| | - David Hilton
- EPSRC Centre for Innovative Manufacturing in Emergent Macromolecular Therapies, Department of Biochemical Engineering, University College London , London WC1H 0AH, U.K.,Department of Biochemical Engineering, University College London , London WC1H 0AH, U.K
| | - Shahina S Ahmad
- Department of Biochemical Engineering, University College London , London WC1H 0AH, U.K
| | - Geoffrey W Platt
- Unchained Laboratories, Unit 706, Avenue E West, Thorp Arch Estate, Wetherby LS23 7EG, U.K
| | - Paul A Dalby
- EPSRC Centre for Innovative Manufacturing in Emergent Macromolecular Therapies, Department of Biochemical Engineering, University College London , London WC1H 0AH, U.K.,Department of Biochemical Engineering, University College London , London WC1H 0AH, U.K
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Lamazares E, Clemente I, Bueno M, Velázquez-Campoy A, Sancho J. Rational stabilization of complex proteins: a divide and combine approach. Sci Rep 2015; 5:9129. [PMID: 25774740 PMCID: PMC4360737 DOI: 10.1038/srep09129] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 02/19/2015] [Indexed: 11/09/2022] Open
Abstract
Increasing the thermostability of proteins is often crucial for their successful use as analytic, synthetic or therapeutic tools. Most rational thermostabilization strategies were developed on small two-state proteins and, unsurprisingly, they tend to fail when applied to the much more abundant, larger, non-fully cooperative proteins. We show that the key to stabilize the latter is to know the regions of lower stability. To prove it, we have engineered apoflavodoxin, a non-fully cooperative protein on which previous thermostabilizing attempts had failed. We use a step-wise combination of structure-based, rationally-designed, stabilizing mutations confined to the less stable structural region, and obtain variants that, according to their van't Hoff to calorimetric enthalpy ratios, exhibit fully-cooperative thermal unfolding with a melting temperature of 75°C, 32 degrees above the lower melting temperature of the non-cooperative wild type protein. The ideas introduced here may also be useful for the thermostabilization of complex proteins through formulation or using specific stabilizing ligands (e.g. pharmacological chaperones).
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Affiliation(s)
- Emilio Lamazares
- 1] Biocomputation and Complex Systems Physics Institute (BIFI)-Joint Unit BIFI-IQFR (CSIC), Universidad de Zaragoza, Zaragoza, Spain [2] Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain
| | - Isabel Clemente
- 1] Biocomputation and Complex Systems Physics Institute (BIFI)-Joint Unit BIFI-IQFR (CSIC), Universidad de Zaragoza, Zaragoza, Spain [2] Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain
| | - Marta Bueno
- 1] Biocomputation and Complex Systems Physics Institute (BIFI)-Joint Unit BIFI-IQFR (CSIC), Universidad de Zaragoza, Zaragoza, Spain [2] Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain
| | - Adrián Velázquez-Campoy
- 1] Biocomputation and Complex Systems Physics Institute (BIFI)-Joint Unit BIFI-IQFR (CSIC), Universidad de Zaragoza, Zaragoza, Spain [2] Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain [3] Fundación ARAID, Gobierno de Aragón, Spain
| | - Javier Sancho
- 1] Biocomputation and Complex Systems Physics Institute (BIFI)-Joint Unit BIFI-IQFR (CSIC), Universidad de Zaragoza, Zaragoza, Spain [2] Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain
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Russo D, Ortore MG, Spinozzi F, Mariani P, Loupiac C, Annighofer B, Paciaroni A. The impact of high hydrostatic pressure on structure and dynamics of β-lactoglobulin. Biochim Biophys Acta Gen Subj 2013; 1830:4974-80. [DOI: 10.1016/j.bbagen.2013.06.040] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Revised: 06/06/2013] [Accepted: 06/29/2013] [Indexed: 01/12/2023]
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10
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The stability of 2-state, 3-state and more-state proteins from simple spectroscopic techniques... plus the structure of the equilibrium intermediates at the same time. Arch Biochem Biophys 2013; 531:4-13. [DOI: 10.1016/j.abb.2012.10.014] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Revised: 10/22/2012] [Accepted: 10/28/2012] [Indexed: 11/20/2022]
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Martínez-Júlvez M, Rojas AL, Olekhnovich I, Espinosa Angarica V, Hoffman PS, Sancho J. Structure of RdxA--an oxygen-insensitive nitroreductase essential for metronidazole activation in Helicobacter pylori. FEBS J 2012; 279:4306-17. [PMID: 23039228 DOI: 10.1111/febs.12020] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Revised: 09/26/2012] [Accepted: 10/03/2012] [Indexed: 11/27/2022]
Abstract
UNLABELLED The RdxA oxygen-insensitive nitroreductase of the human gastric pathogen Helicobacter pylori is responsible for the susceptibility of this organism to the redox active prodrug metronidazole [2-(2-methyl-5-nitro-1H-imidazol-1-yl)ethanol]. Loss-of-function mutations in rdxA are primarily responsible for resistance to this therapeutic. RdxA exhibits potent NADPH oxidase activity under aerobic conditions and metronidazole reductase activity under strictly anaerobic conditions. In the present study, we report the crystal structure of RdxA, which is a homodimer exhibiting domain swapping and containing two molecules of FMN bound at the dimer interface. We have found a gap between the side chain of Tyr47 and the isoalloxazine ring of FMN that appears to be appropriate for substrate binding. The structure does not include residues 97-128, which correspond to a locally unstable part of the NTR from Escherichia coli, and might be involved in cofactor binding. Comparison of H. pylori RdxA with other oxidoreductases of known structure suggests that RdxA may belong to a new subgroup of oxidoreductases in which a cysteine side chain close to the FMN cofactor could be involved in the reductive activity. In this respect, the mutation of C159 to A or S (C159A/S) has resulted in a loss of metronidazole reductase activity but not NADPH oxidase activity. The RdxA structure enables the interpretation of the many loss-of-function mutations described previously, including those affecting C159, a residue whose interaction with FMN is required for the nitroreduction of metronidazole. The present studies provide unique insights into the redox behaviour of the flavin in this key enzyme for metronidazole activation, including a potential use in gene therapy. DATABASE Structural data have been deposited in the Protein Data Bank under accession number 3QDL.
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Affiliation(s)
- Marta Martínez-Júlvez
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain
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