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Pan KY, Liu HH, Tseng MN, Chang HX. Ca 2+ affects the hyphal differentiation to sclerotia formation of Athelia rolfsii. Microbiol Spectr 2024; 12:e0020024. [PMID: 38687071 DOI: 10.1128/spectrum.00200-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 04/05/2024] [Indexed: 05/02/2024] Open
Abstract
RNA-Sequencing (RNA-Seq) and transcriptomic analyses have become powerful tools to study the developmental stages of fungal structures scuh as sclerotia. While RNA-Seq experiments have been set up for many important sclerotia- and microsclerotia-forming fungi, it has not been implemented to study Athelia rolfsii, which is one of the earliest fungi used in literature to uncover the roles of reactive oxygen species (ROS) in stimulating sclerotia formation. This study applied RNA-Seq to profile gene expression in four developmental stages of A. rolfsii sclerotia. Surprisingly, gene ontology and expression patterns suggested that most ROS-scavenging genes were not up-regulated in the stages from hyphal differentiation to the initial sclerotia stage. Using antioxidant and oxidant-amended culture assay, the results suggested none of the ascorbic acid, dithiothreitol (DTT), H2O2, or superoxide dismutase inhibitors [diethyldithiocarbamate (DETC), NaN3, and sodium dodecyl sulfate] affected the sclerotia number. Instead, only glutathione reduced the sclerotia number. Because glutathione has also been suggested to facilitate Ca2+ influx, therefore, glutathione culture assays with the combination of CaCl2, Ca2+-chelator egtazic acid, DETC, and H2O2 were tested on A. rolfsii, as well as two other fungi (Sclerotinia sclerotiorum and Macrophomina phaseolina) for comparison. Although the addition of CaCl2 caused sclerotia or microsclerotia reduction for all three fungi, the CaCl2-ROS interaction was only observed for S. sclerotiorum and M. phaseolina, but not A. rolfsi. Collectively, this study not only pointed out a conserved function of Ca2+ in suppressing fungal sclerotia and microsclerotia formation but also highlighted sclerotia formation of A. rolfsii being only sensitive to Ca2+ and independent of ROS stimuli.IMPORTANCEManagement for plant diseases caused by soil-borne fungal pathogens is challenging because many soil-borne fungal pathogens form sclerotia for long-term survival. Advanced understanding of the molecular and cellular mechanisms of sclerotia formation may provide novel insights to prevent these fungal residues in fields. This study discovered that Ca2+ acts as a negative signal cue to suppress sclerotia and microsclerotia formation in three economically important fungal pathogens. Moreover, the southern blight fungus Athelia rolfsii appears to be only regulated by Ca2+ but not reactive oxygen species. Accordingly, A. rolfsii can be a useful system for studying the detailed mechanism of Ca2+, and the applicability of Ca2+ in reducing sclerotia could be further assessed for disease management.
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Affiliation(s)
- Kuan-Yu Pan
- Department of Plant Pathology and Microbiology, National Taiwan University, Taipei City, Taiwan
| | - Hsien-Hao Liu
- Department of Plant Pathology and Microbiology, National Taiwan University, Taipei City, Taiwan
| | - Min-Nan Tseng
- Kaohsiung District Agricultural Research and Extension Station, Ministry of Agriculture, Pingtung, Taiwan
| | - Hao-Xun Chang
- Department of Plant Pathology and Microbiology, National Taiwan University, Taipei City, Taiwan
- Master Program for Plant Medicine, National Taiwan University, Taipei City, Taiwan
- Center for Biotechnology, National Taiwan University, Taipei City, Taiwan
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Hamre AG, Al-Sadawi R, Johannesen KM, Bisarro B, Kjendseth ÅR, Leiros HKS, Sørlie M. Initial characterization of an iron superoxide dismutase from Thermobifida fusca. J Biol Inorg Chem 2023; 28:689-698. [PMID: 37725277 PMCID: PMC10520107 DOI: 10.1007/s00775-023-02019-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 08/24/2023] [Indexed: 09/21/2023]
Abstract
Superoxide dismutases (SODs) are enzymes that catalyze the dismutation of the superoxide radical anion into O2 and H2O2 in a two-step reaction. They are ubiquitous to all forms of life and four different types of metal centers are detected, dividing this class of enzymes into Cu-/Zn-, Ni-, Mn-, and Fe-SODs. In this study, a superoxide dismutase from the thermophilic bacteria Thermobifida fusca (TfSOD) was cloned and expressed before the recombinant enzyme was characterized. The enzyme was found to be active for superoxide dismutation measured by inhibition of cytochrome c oxidation and the inhibition of the autoxidation of pyrogallol. Its pH-optimum was determined to be 7.5, while it has a broad temperature optimum ranging from 20 to 90 °C. Combined with the Tm that was found to be 78.5 ± 0.5 °C at pH 8.0, TfSOD can be defined as a thermostable enzyme. Moreover, the crystal structure of TfSOD was determined and refined to 1.25 Å resolution. With electron paramagnetic resonance spectroscopy, it was confirmed that iron is the metal co-factor of TfSOD. The cell potential (Em) for the TfSOD-Fe3+/TfSOD-Fe2+ redox couple was determined to be 287 mV.
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Affiliation(s)
- Anne Grethe Hamre
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, PO 5003, 1432, Ås, Norway
| | - Rim Al-Sadawi
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, PO 5003, 1432, Ås, Norway
| | - Kirsti Merete Johannesen
- Department of Chemistry, Faculty of Science and Technology, UiT The Arctic University of Norway, 9037, Tromsö, Norway
| | - Bastien Bisarro
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, PO 5003, 1432, Ås, Norway
| | - Åsmund Røhr Kjendseth
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, PO 5003, 1432, Ås, Norway
| | - Hanna-Kirsti S Leiros
- Department of Chemistry, Faculty of Science and Technology, UiT The Arctic University of Norway, 9037, Tromsö, Norway
| | - Morten Sørlie
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, PO 5003, 1432, Ås, Norway.
- Department for Physics and Technology, Faculty of Science and Technology, UiT The Arctic University of Norway, 9037, Tromsö, Norway.
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Dong X, Wang W, Li S, Han H, Lv P, Yang C. Thermoacidophilic Alicyclobacillus Superoxide Dismutase: Good Candidate as Additives in Food and Medicine. Front Microbiol 2021; 12:577001. [PMID: 33815303 PMCID: PMC8014015 DOI: 10.3389/fmicb.2021.577001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Accepted: 02/26/2021] [Indexed: 11/30/2022] Open
Abstract
Thermoacidophilic Alicyclobacillus strains attract great interests as the resource of thermostable or acidic enzymes. In this study, a putative gene encoding superoxide dismutase (AaSOD) was identified in a thermoacidophilic Alicyclobacillus strain. With a 16-fold activity observed, the AaSOD activity expressing in the medium of manganese enrichment was much higher than that in the iron medium. In addition, the purified AaSOD can be reconstituted exclusively with either Fe2+ or Mn2+, with its Mn-bound protein showing 25-fold activity than that of Fe-bound form. The optimal temperature for AaSOD reaction was 35°C, and was highly stable at any certain temperature up to 80°C. Of particular interest, the enzyme is found to be very stable across a wide pH range spanning from 2.0 to 10.0, which confers its robust stability in the acidic stomach environment and implies striking potentials as food additive and for medical use.
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Affiliation(s)
- Xueqian Dong
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, China.,Shandong Food Ferment Industry Research & Design Institute, QiLu University of Technology (Shandong Academy of Sciences), Jinan, China
| | - Wei Wang
- Shandong Food Ferment Industry Research & Design Institute, QiLu University of Technology (Shandong Academy of Sciences), Jinan, China
| | - Shannan Li
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, China
| | - Hongyu Han
- Shandong Food Ferment Industry Research & Design Institute, QiLu University of Technology (Shandong Academy of Sciences), Jinan, China
| | - Peiwen Lv
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, China
| | - Chunyu Yang
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, China
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Characterisation of recombinant thermostable manganese-superoxide dismutase (NeMnSOD) from Nerium oleander. Mol Biol Rep 2020; 47:3251-3270. [DOI: 10.1007/s11033-020-05374-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 03/07/2020] [Indexed: 12/17/2022]
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Characteristics of a Novel Manganese Superoxide Dismutase of a Hadal Sea Cucumber ( Paelopatides sp.) from the Mariana Trench. Mar Drugs 2019; 17:md17020084. [PMID: 30717090 PMCID: PMC6410416 DOI: 10.3390/md17020084] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 01/09/2019] [Accepted: 01/15/2019] [Indexed: 12/18/2022] Open
Abstract
A novel, cold-adapted, and acid-base stable manganese superoxide dismutase (Ps-Mn-SOD) was cloned from hadal sea cucumber Paelopatides sp. The dimeric recombinant enzyme exhibited approximately 60 kDa in molecular weight, expressed activity from 0 °C to 70 °C with an optimal temperature of 0 °C, and resisted wide pH values from 2.2⁻13.0 with optimal activity (> 70%) at pH 5.0⁻12.0. The Km and Vmax of Ps-Mn-SOD were 0.0329 ± 0.0040 mM and 9112 ± 248 U/mg, respectively. At tested conditions, Ps-Mn-SOD was relatively stable in divalent metal ion and other chemicals, such as β-mercaptoethanol, dithiothreitol, Tween 20, Triton X-100, and Chaps. Furthermore, the enzyme showed striking stability in 5 M urea or 4 M guanidine hydrochloride, resisted digestion by proteases, and tolerated a high hydrostatic pressure of 100 MPa. The resistance of Ps-Mn-SOD against low temperature, extreme acidity and alkalinity, chemicals, proteases, and high pressure make it a potential candidate in biopharmaceutical and nutraceutical fields.
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Branco R, Morais PV. Two superoxide dismutases from TnOtchr are involved in detoxification of reactive oxygen species induced by chromate. BMC Microbiol 2016; 16:27. [PMID: 26944876 PMCID: PMC4779226 DOI: 10.1186/s12866-016-0648-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 02/29/2016] [Indexed: 11/29/2022] Open
Abstract
Background Superoxide dismutases (SOD) have been reported as the most relevant bacterial enzymes involved in cells protection from reactive oxygen species (ROS). These toxic species are often the product of heavy metal stress. Results Two genes, chrC and chrF, from TnOtchr genetic determinant of strain Ochrobactrum tritici 5bvl1 were cloned in Escherichia coli in order to overexpress the respective proteins. Both proteins were purified and characterized as superoxide dismutases. ChrC was confirmed as being a Fe-SOD, and the enzymatic activity of the ChrF, not inhibited by hydrogen peroxide or potassium cyanide, suggested its inclusion in the Mn-SOD family. This identification was supported by chemical quantification of total metal content in purified enzyme. Both enzymes showed a maximum activity between pH 7.2-7.5. ChrF retained nearly full activity over a broader range of pH and was slightly more thermostable than ChrC. The genes encoding these enzymes in strain O. tritici 5bvl1 were inactivated, developing single and double mutants, to understand the contribution of these enzymes in detoxification mechanism of reactive oxygen species induced by chromate. During chromate stress, assays using fluorescent dyes indicated an increase of these toxic compounds in chrC, chrF and chrC/chrF mutant cells. Conclusions In spite of the multiple genes coding for putative superoxide dismutase enzymes detected in the genome of O. tritici 5bvl1, the ChrC and ChrF might help the strain to decrease the levels of reactive oxygen species in cells.
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Affiliation(s)
- Rita Branco
- CEMUC-Department of Mechanical Engineering, University of Coimbra, 3030-788, Coimbra, Portugal. .,Department of Life Sciences, University of Coimbra, 3001-401, Coimbra, Portugal.
| | - Paula V Morais
- CEMUC-Department of Mechanical Engineering, University of Coimbra, 3030-788, Coimbra, Portugal. .,Department of Life Sciences, University of Coimbra, 3001-401, Coimbra, Portugal.
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Li M, Zhu L, Wang W. Improving the thermostability and stress tolerance of an archaeon hyperthermophilic superoxide dismutase by fusion with a unique N-terminal domain. SPRINGERPLUS 2016; 5:241. [PMID: 27026935 PMCID: PMC4771647 DOI: 10.1186/s40064-016-1854-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Accepted: 02/15/2016] [Indexed: 11/10/2022]
Abstract
The superoxide dismutase from the archaeon Sulfolobus solfataricus (SOD Ss ) is a well-studied hyperthermophilic SOD with crystal structure and possible thermostability factors characterized. Previously, we discovered an N-terminal domain (NTD) in a thermophilic SOD from Geobacillus thermodenitrificans NG80-2 which confers heat resistance on homologous mesophilic SODs. The present study therefore aimed to further improve the thermostability and stress tolerance of SOD Ss via fusion with this NTD. The recombinant protein, rSOD Ss , exhibited improved thermophilicity, higher working temperature, improved thermostability, broader pH stability, and enhanced tolerance to inhibitors and organic media than SOD Ss without any alterations in its oligomerization state. These results suggest that the NTD is an excellent candidate for improving stability of both mesophilic and thermophilic SOD from either bacteria or archaea via simple genetic manipulation. Therefore, this study provides a general, feasible and highly useful strategy for generating extremely thermostable SODs for industrial applications.
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Affiliation(s)
- Mingchang Li
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, Tianjin, 300457 People's Republic of China
| | - Lin Zhu
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, Tianjin, 300457 People's Republic of China
| | - Wei Wang
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, Tianjin, 300457 People's Republic of China ; Tianjin Key Laboratory of Microbial Functional Genomics, TEDA, Tianjin, 300457 People's Republic of China
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A novel mechanism of protein thermostability: a unique N-terminal domain confers heat resistance to Fe/Mn-SODs. Sci Rep 2014; 4:7284. [PMID: 25445927 PMCID: PMC4250934 DOI: 10.1038/srep07284] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Accepted: 11/14/2014] [Indexed: 11/22/2022] Open
Abstract
Superoxide dismutases (SODs), especially thermostable SODs, are widely applied in medical treatments, cosmetics, food, agriculture, and other industries given their excellent antioxidant properties. A novel thermostable cambialistic SOD from Geobacillus thermodenitrificans NG80-2 exhibits maximum activity at 70°C and high thermostability over a broad range of temperatures (20–80°C). Unlike other reported SODs, this enzyme contains an extra repeat-containing N-terminal domain (NTD) of 244 residues adjacent to the conserved functional SODA domain. Deletion of the NTD dramatically decreased its optimum active temperature (OAT) to 30°C and also impaired its thermostability. Conversely, appending the NTD to a mesophilic counterpart from Bacillus subtilis led to a moderately thermophilic enzyme (OAT changed from 30 to 55°C) with improved heat resistance. Temperature-dependant circular dichroism analysis revealed the enhanced conformational stability of SODs fused with this NTD. Furthermore, the NTD also contributes to the stress resistance of host proteins without altering their metal ion specificity or oligomerisation form except for a slight effect on their pH profile. We therefore demonstrate that the NTD confers outstanding thermostability to the host protein. To our knowledge, this is the first discovery of a peptide capable of remarkably improving protein thermostability and provides a novel strategy for bioengineering thermostable SODs.
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Yin C, Zhao W, Zhu J, Zheng L, Chen L, Ma A. Cloning and characterization of a differentially expressed mitochondrial manganese superoxide dismutase gene from Pleurotus ostreatus. ANN MICROBIOL 2014. [DOI: 10.1007/s13213-014-0999-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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Yin C, Zhao W, Zheng L, Chen L, Tan Q, Shang X, Ma A. High-level Expression of a Manganese Superoxide Dismutase (PoMn-SOD) from Pleurotus ostreatus in Pichia pastoris. Appl Biochem Biotechnol 2014; 174:259-69. [DOI: 10.1007/s12010-014-1057-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 07/14/2014] [Indexed: 10/25/2022]
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Cloning and characterization of a new manganese superoxide dismutase from deep-sea thermophile Geobacillus sp. EPT3. World J Microbiol Biotechnol 2013; 30:1347-57. [DOI: 10.1007/s11274-013-1536-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Accepted: 10/21/2013] [Indexed: 10/26/2022]
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Li RK, Fu CL, Chen P, Ng TB, Ye XY. High-level expression of a sika deer (Cervus nippon) Cu/Zn superoxide dismutase in Pichia pastoris and its characterization. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2013; 35:185-192. [PMID: 23328117 DOI: 10.1016/j.etap.2012.11.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Revised: 11/22/2012] [Accepted: 11/25/2012] [Indexed: 06/01/2023]
Abstract
Production of a sika deer Cu/Zn-SOD was achieved in Pichia pastoris after the reconstituted expression vector pPIC9K was transformed into the strain GS115. By employing Saccharomyces cerevisiae secretion signal peptide (α-factor) under the regulation of the methanol-inducible promoter of the gene of alcohol oxidase 1 (AOX1), sika deer Cu/Zn-SOD with a molecular mass of 16kDa was expressed while recombinant sika deer Cu/Zn-SOD with an activity of 3500U/mL was obtained from a 5L bioreactor. After two successive steps of chromatography on DEAE-650C and Superdex75, recombinant sika deer Cu/Zn-SOD was obtained with 13.8% yield, 14.5-fold purification, and a specific activity of 3447U/mg. Its optimum temperature and optimum pH were 40°C and 7.0, respectively.
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Affiliation(s)
- Ren-Kuan Li
- College of Biological Science and Technology, Fuzhou University, PR China
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Cheng GY, Liu J, Tao MX, Lu CM, Wu GR. Activity, thermostability and isozymes of superoxide dismutase in 17 edible mushrooms. J Food Compost Anal 2012. [DOI: 10.1016/j.jfca.2012.01.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Chambergo FS, Valencia EY, Ferreira-Júnior JR, Camilo CM, Campana PT. Conformational stability of recombinant manganese superoxide dismutase from the filamentous fungus Trichoderma reesei. Int J Biol Macromol 2012; 50:19-24. [DOI: 10.1016/j.ijbiomac.2011.09.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2011] [Revised: 09/14/2011] [Accepted: 09/14/2011] [Indexed: 11/27/2022]
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Expression of a novel thermostable Cu, Zn-superoxide dismutase from Chaetomium thermophilum in Pichia pastoris and its antioxidant properties. Biotechnol Lett 2011; 33:1127-32. [DOI: 10.1007/s10529-011-0543-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Accepted: 01/20/2011] [Indexed: 01/23/2023]
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Bafana A, Dutt S, Kumar A, Kumar S, Ahuja PS. The basic and applied aspects of superoxide dismutase. ACTA ACUST UNITED AC 2011. [DOI: 10.1016/j.molcatb.2010.11.007] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Areekit S, Kanjanavas P, Khawsak P, Pakpitchareon A, Potivejkul K, Chansiri G, Chansiri K. Cloning, expression, and characterization of thermotolerant manganese superoxide dismutase from Bacillus sp. MHS47. Int J Mol Sci 2011; 12:844-56. [PMID: 21340017 PMCID: PMC3039983 DOI: 10.3390/ijms12010844] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Revised: 01/11/2011] [Accepted: 01/21/2011] [Indexed: 11/28/2022] Open
Abstract
A superoxide dismutase gene from thermotolerant Bacillus sp. MHS47 (MnSOD47) was cloned, sequenced, and expressed. The gene has an open reading frame of 612 bp, corresponding to 203 deduced amino acids, with high homology to the amino acid sequences of B. thuringiensis (accession no. EEN01322), B. anthracis (accession no. NP_846724), B. cereus (accession no. ZP_04187911), B. weihenstephanensis (accession no. YP_001646918), and B. pseudomycoides. The conserved manganese-binding sites (H28, H83, D165, and H169) show that MnSOD47 has the specific characteristics of the manganese superoxide dismutase (MnSOD) enzymes. MnSOD47 expressed an enzyme with a molecular weight of approximately 22.65 kDa and a specific activity of 3537.75 U/mg. The enzyme is active in the pH range 7–8.5, with an optimum pH of 7.5, and at temperatures in the range 30–45 °C, with an optimum temperature of 37 °C. Tests of inhibitors and metal ions indicated that the enzyme activity is inhibited by sodium azide, but not by hydrogen peroxide or potassium cyanide. These data should benefit future studies of MnSODs in other microorganisms and the biotechnological production of MnSOD47, and could also be used to develop a biosensor for the detection of antioxidants and free radical activity. In the future, this basic knowledge could be applicable to the detection of cancer risks in humans and therapeutic treatments.
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Affiliation(s)
- Supatra Areekit
- Department of Biochemistry, Faculty of Medicine, Srinakharinwirot University, Bangkok 10110, Thailand; E-Mails: (S.A.); (P.K.); (A.P.)
| | - Pornpimon Kanjanavas
- Department of Biology, Faculty of Science and Technology, Rambhai Barni Rajabhat University, Chanthaburi 22000, Thailand; E-Mail:
| | - Paisarn Khawsak
- Department of Biochemistry, Faculty of Medicine, Srinakharinwirot University, Bangkok 10110, Thailand; E-Mails: (S.A.); (P.K.); (A.P.)
| | - Arda Pakpitchareon
- Department of Biochemistry, Faculty of Medicine, Srinakharinwirot University, Bangkok 10110, Thailand; E-Mails: (S.A.); (P.K.); (A.P.)
| | - Kajeenart Potivejkul
- Department of Biology, Faculty of Science, Srinakharinwirot University, Bangkok 10110, Thailand; E-Mail:
| | - Gaysorn Chansiri
- Department of Pharmaceutical Technology, Faculty of Pharmacy, Silpakorn University, Nakhon Pathom 73000, Thailand; E-Mail:
| | - Kosum Chansiri
- Department of Biochemistry, Faculty of Medicine, Srinakharinwirot University, Bangkok 10110, Thailand; E-Mails: (S.A.); (P.K.); (A.P.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +662-664-1000(4605); Fax: +662-664-1000(4618)
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