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Park JH, Lee S, Shin E, Abdi Nansa S, Lee SJ. The Transposition of Insertion Sequences in Sigma-Factor- and LysR-Deficient Mutants of Deinococcus geothermalis. Microorganisms 2024; 12:328. [PMID: 38399731 PMCID: PMC10892881 DOI: 10.3390/microorganisms12020328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 01/29/2024] [Accepted: 02/01/2024] [Indexed: 02/25/2024] Open
Abstract
Some insertion sequence (IS) elements were actively transposed using oxidative stress conditions, including gamma irradiation and hydrogen peroxide treatment, in Deinococcus geothermalis, a radiation-resistant bacterium. D. geothermalis wild-type (WT), sigma factor gene-disrupted (∆dgeo_0606), and LysR gene-disrupted (∆dgeo_1692) mutants were examined for IS induction that resulted in non-pigmented colonies after gamma irradiation (5 kGy) exposure. The loss of pigmentation occurred because dgeo_0524, which encodes a phytoene desaturase in the carotenoid pathway, was disrupted by the transposition of IS elements. The types and loci of the IS elements were identified as ISDge2 and ISDge6 in the ∆dgeo_0606 mutant and ISDge5 and ISDge7 in the ∆dgeo_1692 mutant, but were not identified in the WT strain. Furthermore, 80 and 100 mM H2O2 treatments induced different transpositions of IS elements in ∆dgeo_0606 (ISDge5, ISDge6, and ISDge7) and WT (ISDge6). However, no IS transposition was observed in the ∆dgeo_1692 mutant. The complementary strain of the ∆dgeo_0606 mutation showed recovery effects in the viability assay; however, the growth-delayed curve did not return because the neighboring gene dgeo_0607 was overexpressed, probably acting as an anti-sigma factor. The expression levels of certain transposases, recognized as pivotal contributors to IS transposition, did not precisely correlate with active transposition in varying oxidation environments. Nevertheless, these findings suggest that specific IS elements integrated into dgeo_0524 in a target-gene-deficient and oxidation-source-dependent manner.
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Affiliation(s)
| | | | | | | | - Sung-Jae Lee
- Department of Biology, Kyung Hee University, Seoul 02447, Republic of Korea; (J.H.P.); (S.L.); (E.S.); (S.A.N.)
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Zhang L, Li H, Zhang X, Li Q, Zhu G, Liu FQ. A marine coating: Self-healing, stable release of Cu 2+, anti-biofouling. MARINE POLLUTION BULLETIN 2023; 195:115524. [PMID: 37703634 DOI: 10.1016/j.marpolbul.2023.115524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 09/03/2023] [Accepted: 09/06/2023] [Indexed: 09/15/2023]
Abstract
We developed a marine coating consisting of Cu-MOF-74, multi-walled carbon nanotube containing carboxyl groups (MWCNT-COOH) and self-healing polymers, which simultaneously possesses self-healing and anti-biofouling properties. Cu-MOF-74 can stably release Cu2+ by virtue of the coordination dissociative mechanism. Studies have proved that MWCNT can inhibit the growth of bacteria, so adding the MWCNT can help to reduce the amount of the copper ions and ensure the antibacterial effect of the coating. In addition, the cross-linked network and abundant -COOH provided by the polymers and MWCNT-COOH further prevent the loss of copper ions. Moreover, the coating we prepared has good performance of self-healing at room temperature or slightly heated because the polymers possess abundant non-covalent hydrogen bonds. Finally, the coating not only has superior antibacterial property, but also effectively prevents the adhesion of macrofouling organism. Therefore, the coating has a longer service life and its environmental friendliness has also been improved.
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Affiliation(s)
- Liuqin Zhang
- School of Chemical Engineering and Technology, Sun Yat-sen University, Zhuhai 519082, China; School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Huali Li
- School of Chemical Engineering and Technology, Sun Yat-sen University, Zhuhai 519082, China; School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Xiaohu Zhang
- School of Chemical Engineering and Technology, Sun Yat-sen University, Zhuhai 519082, China
| | - Qiuping Li
- Aviation Key Laboratory of Science and Technology on Structural Corrosion Prevention and Control, China Special Vehicle Research Institute, Jingmen 448035, China
| | - Guangyu Zhu
- School of Chemical Engineering and Technology, Sun Yat-sen University, Zhuhai 519082, China
| | - Fa-Qian Liu
- School of Chemical Engineering and Technology, Sun Yat-sen University, Zhuhai 519082, China.
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Physiological roles of catalases Cat1 and Cat2 in Myxococcus xanthus. J Microbiol 2022; 60:1168-1177. [PMID: 36279102 DOI: 10.1007/s12275-022-2277-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 09/21/2022] [Accepted: 09/27/2022] [Indexed: 11/07/2022]
Abstract
Catalases are key antioxidant enzymes in aerobic organisms. Myxococcus xanthus expresses two monofunctional catalases, small-subunit Cat1 and large-subunit Cat2. The Km of H2O2 for recombinant Cat1 and Cat2 were 14.0 and 9.0 mM, respectively, and the catalytic efficiency of Cat2 (kcat/Km = 500 sec-1 mM-1) was 4-fold higher than that of Cat1. The activity ratio of Cat1 to Cat2 in the exponential growth phase of M. xanthus was 1 to 3-4. A Cat1-deficient strain was constructed, whereas a Cat2-deficient strain could not be produced In H2O2-supplemented medium, the cat1 mutant exhibited marked growth retardation and a longer generation time than the wild-type (wt) strain. After 2 h of incubation in 0.5 mM H2O2-supplemented medium, the catalase activity of the wt strain significantly increased (by 64-fold), but that of the cat1 mutant strain did not. Under starvation-induced developmental conditions, catalase activity was induced by approximately 200-fold in both wt and cat1 strains, although in the mutant the activity increase as well as spore formation occurred one day later, indicating that the induction of catalase activity during starvation was due to Cat2. In wt starved cells, catalase activity was not induced by H2O2. These results suggest that Cat2 is the primary housekeeping catalase during M. xanthus growth and starvation-induced development, whereas Cat1 may have a complementary role, being responsible for the rapid degradation of H2O2 in proliferating vegetative cells subjected to oxidative stress.
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Wang J, Liu J, Zhao Y, Sun M, Yu G, Fan J, Tian Y, Hu B. OxyR contributes to virulence of Acidovorax citrulli by regulating anti-oxidative stress and expression of flagellin FliC and type IV pili PilA. Front Microbiol 2022; 13:977281. [PMID: 36204623 PMCID: PMC9530317 DOI: 10.3389/fmicb.2022.977281] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 08/31/2022] [Indexed: 11/25/2022] Open
Abstract
In many bacteria, OxyR acts as a transcriptional regulator that facilitates infection via degrading hydrogen peroxide (H2O2) generated by the host defense response. Previous studies showed that OxyR also plays an important role in regulating biofilm formation, cell motility, pili relate-genes expression, and surface polysaccharide production. However, the role of OxyR has not been determined in Acidovorax citrulli strain xjl12. In the current study, the qRT-PCR and western blot assays revealed that the expression level of oxyR was significantly induced by H2O2. The oxyR deletion mutant of A. citrulli was significantly impaired bacterial tolerance to oxidative stress and reduced catalase (CAT) activity. In addition, oxyR mutant resulted in reduced swimming motility, twitching motility, biofilm formation, virulence, and bacterial growth in planta by significantly affecting flagellin and type IV pili-related gene (fliC and pilA) expression. The qRT-PCR assays and western blot revealed that OxyR positively regulated the expression of fliC and pilA. Furthermore, bacterial one-hybrid assay demonstrated that OxyR directly affected pilA and fliC promoter. Through bacterial two-hybrid assay, it was found that OxyR can directly interact with PilA and FliC. These results suggest that OxyR plays a major role in the regulating of a variety of virulence traits, and provide a foundation for future research on the global effects of OxyR in A. citrulli.
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Affiliation(s)
- Jianan Wang
- College of Plant Protection and Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, Nanjing, China
| | - Jun Liu
- College of Plant Protection and Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, Nanjing, China
- Institute of Plant Protection and Soil Fertilizer, Hubei Academy of Agricultural Sciences, Wuhan, China
| | - Yuqiang Zhao
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences (Nanjing Botanical Garden Mem. Sun Yat-Sen), Nanjing, China
| | - Minghui Sun
- College of Plant Protection and Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, Nanjing, China
| | - Guixu Yu
- College of Plant Protection and Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, Nanjing, China
| | - Jiaqin Fan
- Laboratory of Bacteriology, Department of Plant Pathology, Nanjing Agricultural University, Nanjing, China
| | - Yanli Tian
- College of Plant Protection and Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, Nanjing, China
- *Correspondence: Yanli Tian,
| | - Baishi Hu
- College of Plant Protection and Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, Nanjing, China
- Baishi Hu,
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Lee C, Choo K, Lee SJ. Active Transposition of Insertion Sequences by Oxidative Stress in Deinococcus geothermalis. Front Microbiol 2020; 11:558747. [PMID: 33224109 PMCID: PMC7674623 DOI: 10.3389/fmicb.2020.558747] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 10/05/2020] [Indexed: 11/17/2022] Open
Abstract
Radiation-resistant bacterium Deinococcus geothermalis has a total of 73 insertion sequences (ISs) in genomes, and some of them are actively transposed to other loci with replicative mode due to oxidative stress of hydrogen peroxide treatment. Here, we detected two transposition events in wild-type (WT) strain and LysR family member gene disrupted strain (Δdgeo_2840). Similar to our previous report (Lee et al., 2019), phytoene desaturase (dgeo_0524), a key enzyme of carotenoid biosynthesis, was disrupted by the integration of IS element, thereby detected a single phenotypically non-pigmented colony in each WT and Δdgeo_2840 strain. Two separate types of IS element have been integrated into non-pigmented clones: ISDge11 for WT and ISDge6 for Δdgeo_2840 strain. Surprisingly, Δdgeo_2840 mutant strain revealed higher resistance to oxidative stress than WT strain at late exponential growth phase. From the qRT-PCR analysis, OxyR (dgeo_1888) was highly up-regulated to 30-fold by oxidative stress through hydrogen peroxide treatment in both WT and Δdgeo_2840 mutant strains. However, the oxidative stress response enzyme, catalase or superoxide dismutase, was not significantly induced by overexpressed OxyR. Thus, a putative LysR family regulator Dgeo_2840 controlled the expression of ISDge6 type transposase and the induction of OxyR under oxidative condition. There is LysR family DNA-binding protein dependent active transposition of specific type IS and the up-regulated OxyR has not positively controlled ROS scavenger enzymes in D. geothermalis.
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Affiliation(s)
- Chanjae Lee
- Department of Biology, Kyung Hee University, Seoul, South Korea
| | - Kyungsil Choo
- Department of Biology, Kyung Hee University, Seoul, South Korea
| | - Sung-Jae Lee
- Department of Biology, Kyung Hee University, Seoul, South Korea
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Ndemueda A, Pereira I, Faustino MAF, Cunha Â. Photodynamic inactivation of the phytopathogenic bacterium Xanthomonas citri subsp. citri. Lett Appl Microbiol 2020; 71:420-427. [PMID: 32628776 DOI: 10.1111/lam.13350] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 06/13/2020] [Accepted: 06/29/2020] [Indexed: 12/12/2022]
Abstract
The present work intended to evaluate the applicability of photodynamic inactivation (PDI) of Xanthomonas citri subsp. citri with toluidine blue O (TBO), a commercial photosensitizer, as a strategy to control citrus canker. Assays were conducted with cell suspensions and biofilms, constructed either on polypropylene microtubes (in vitro assays) or on the surface of orange leaves (ex vivo assays), in the presence of TBO and under irradiation with artificial white light or natural sunlight. PDI assays using TBO alone caused a maximum 5·8 log10 reduction of X. citri viable cells in suspensions, and a much smaller inactivation (1·5 log10) in biofilms. However, concomitant use of KI potentiated the TBO photosensitization. Biofilms were inactivated down to the detection limit (>6 log10 reduction) with 5·0 µmol l-1 TBO + 10 mmol l-1 KI (in vitro) or 5·0 µmol l-1 TBO + 100 mmol l-1 KI (ex vivo) after artificial white light irradiation. Under natural sunlight, a reduction down to the detection limit of the Miles-Misra method was achieved with 50 µmol l-1 TBO and 100 mmol l-1 KI. PDI has potential to be applied in the control of citrus canker in field conditions although further studies are needed to show that there are no risks to plant physiology or fruit quality. SIGNIFICANCE AND IMPACT OF THE STUDY: Xanthomonas citri subsp. citri is a major cause of disease in citrus orchards. Because of the low efficacy and high environmental toxicity of copper-based treatments, there is growing interest on more sustainable phytosanitary approaches. Photodynamic inactivation (PDI) is being successfully used to control infectious agents and literature reports indicate that it is effective against some fungi and bacteria attacking fruit crops. The results of the present work open the perspective of using a low-cost photosensitizer and sunlight, as energy source, to control of the causative agent of citrus canker.
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Affiliation(s)
- A Ndemueda
- CESAM and Department of Biology, University of Aveiro, Aveiro, Portugal
| | - I Pereira
- CESAM and Department of Biology, University of Aveiro, Aveiro, Portugal
| | - M A F Faustino
- LAQV-REQUIMTE and Department of Chemistry, University of Aveiro, Aveiro, Portugal
| | - Â Cunha
- CESAM and Department of Biology, University of Aveiro, Aveiro, Portugal
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Fan G, Bao M, Wang B, Wu S, Luo L, Li B, Lin J. Inhibitory Effects of Cu 2O/SiO 2 on the Growth of Microcystis aeruginosa and Its Mechanism. NANOMATERIALS 2019; 9:nano9121669. [PMID: 31766783 PMCID: PMC6955810 DOI: 10.3390/nano9121669] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 11/15/2019] [Accepted: 11/17/2019] [Indexed: 11/17/2022]
Abstract
In this study, a novel nanomaterial Cu2O/SiO2 was synthesized based on nano-SiO2, and the inhibitory effects of different concentrations of Cu2O/SiO2 on the growth of Microcystis aeruginosa (M. aeruginosa) were studied. At the same time, the mechanism of Cu2O/SiO2 inhibiting the growth of M. aeruginosa was discussed from the aspects of Cu2+ release, chlorophyll a destruction, oxidative damage, total protein, and the phycobiliprotein of algae cells. The results showed that low doses of Cu2O/SiO2 could promote the growth of M. aeruginosa. When the concentration of Cu2O/SiO2 reached 10 mg/L, it exhibited the best inhibitory effect on M. aeruginosa, and the relative inhibition rate reached 294% at 120 h. In terms of the algae inhibition mechanism, Cu2O/SiO2 will release Cu2+ in the solution and induce metal toxicity to algae cells. At the same time, M. aeruginosa might suffer oxidative damage by the free radicals, such as hydroxyl radicals released from Cu2O/SiO2, affecting the physiological characteristics of algae cells. Moreover, after the addition of Cu2O/SiO2, a decrease in the content of chlorophyll a, total soluble protein, and phycobiliprotein was found, which eventually led to the death of M. aeruginosa. Therefore, Cu2O/SiO2 can be used as an algaecide inhibitor for controlling harmful cyanobacteria blooms.
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Affiliation(s)
- Gongduan Fan
- College of Civil Engineering, Fuzhou University, Fujian 350116, China; (M.B.); (J.L.)
- Correspondence: (G.F.); (B.W.)
| | - Minchen Bao
- College of Civil Engineering, Fuzhou University, Fujian 350116, China; (M.B.); (J.L.)
| | - Bo Wang
- IER Environmental Protection Engineering Technology Co., Ltd., Shenzhen 518071, China; (S.W.); (L.L.); (B.L.)
- School of Urban Planning and Design, Shenzhen Graduate School, Peking University, Shenzhen 518055, China
- Correspondence: (G.F.); (B.W.)
| | - Shimin Wu
- IER Environmental Protection Engineering Technology Co., Ltd., Shenzhen 518071, China; (S.W.); (L.L.); (B.L.)
| | - Lingxi Luo
- IER Environmental Protection Engineering Technology Co., Ltd., Shenzhen 518071, China; (S.W.); (L.L.); (B.L.)
| | - Binhui Li
- IER Environmental Protection Engineering Technology Co., Ltd., Shenzhen 518071, China; (S.W.); (L.L.); (B.L.)
| | - Jiuhong Lin
- College of Civil Engineering, Fuzhou University, Fujian 350116, China; (M.B.); (J.L.)
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Fan G, Bao M, Zheng X, Hong L, Zhan J, Chen Z, Qu F. Growth inhibition of harmful cyanobacteria by nanocrystalline Cu-MOF-74: Efficiency and its mechanisms. JOURNAL OF HAZARDOUS MATERIALS 2019; 367:529-538. [PMID: 30641423 DOI: 10.1016/j.jhazmat.2018.12.070] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 12/01/2018] [Accepted: 12/19/2018] [Indexed: 05/10/2023]
Abstract
Metal-organic Frameworks (MOFs) as a new type of nanomaterials are extensively used in various fields of environment pollution remediation. However, the MOFs are rarely applied in the removal of cyanobacterial blooms, and more fundamental investigation is warrant for more insights into mechanisms for algae inhibition. In this study, Cu-MOF-74 was synthesized by a simple hydrothermal method, and its inhibitory effect on the growth of Microcystis aeruginosa was studied. Furthermore, its mechanisms were explored with respect to metal ion release, agglomeration, shading and algal cell membrane breakage, production of extracellular hydroxyl radical and intracellular reactive oxygen species. The results showed that the inhibition rate of M. aeruginosa was 372% after 24-h exposure when the concentration of Cu-MOF-74 exceeded 1 mg/L. However, the addition of Cu-MOF-74 at the concentration lower than 0.1 mg/L promoted the algal growth. The inhibition of algal growth by Cu-MOF-74 was basically attributed to the presence of hydroxyl radical and intracellular reactive oxygen species, with the released Cu2+ and cell aggregation involved to some extent. Overall, nanocrystalline Cu-MOF-74 is of great potential in the control of harmful cyanobacterial blooms and the inhibition is specific to the concentration of Cu-MOF-74.
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Affiliation(s)
- Gongduan Fan
- College of Civil Engineering, Fuzhou University, 350116 Fujian, China; State Key Laboratory of Photocatalysis on Energy and Environment, Fuzhou University, 350002 Fujian, China.
| | - Minchen Bao
- College of Civil Engineering, Fuzhou University, 350116 Fujian, China
| | - Xiaomei Zheng
- College of Civil Engineering, Fuzhou University, 350116 Fujian, China
| | - Liang Hong
- College of Civil Engineering, Fuzhou University, 350116 Fujian, China
| | - Jiajun Zhan
- College of Civil Engineering, Fuzhou University, 350116 Fujian, China
| | - Zhong Chen
- College of Civil Engineering, Fuzhou University, 350116 Fujian, China
| | - Fangshu Qu
- School of Civil Engineering, Guangzhou University, Guangzhou, Guangdong, 510006, China.
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Karmakar S, Datta A. Understanding the Reactivity of CO3·– and NO2· Radicals toward S-Containing and Aromatic Amino Acids. J Phys Chem B 2017; 121:7621-7632. [DOI: 10.1021/acs.jpcb.7b05186] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Sharmistha Karmakar
- Department of Spectroscopy, Indian Association for the Cultivation of Science, 2A and 2B Raja S. C. Mullick Road,
Jadavpur, 700032 Kolkata, West Bengal, India
| | - Ayan Datta
- Department of Spectroscopy, Indian Association for the Cultivation of Science, 2A and 2B Raja S. C. Mullick Road,
Jadavpur, 700032 Kolkata, West Bengal, India
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Gao T, Li Y, Ding M, Chai Y, Wang Q. The phosphotransferase system gene ptsI in Bacillus cereus regulates expression of sodA2 and contributes to colonization of wheat roots. Res Microbiol 2017; 168:524-535. [PMID: 28478075 DOI: 10.1016/j.resmic.2017.04.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 04/01/2017] [Accepted: 04/04/2017] [Indexed: 12/21/2022]
Abstract
Plant growth-promoting rhizobacteria effectively enhance plant growth and root colonization by the bacteria is a prerequisite during the process. Bacillus cereus 905, a rhizosphere bacterium originally isolated from wheat roots, colonizes the wheat rhizosphere with a large population size. We previously showed that a manganese-containing superoxide dismutase (MnSOD2), encoded by the sodA2 gene, plays an important role in colonization of the wheat rhizosphere by B. cereus 905. In this study, we identified a gene, ptsI, which positively regulates transcription of sodA2. ptsI encodes Enzyme I of the phosphotransferase system (PTS), a major regulator of carbohydrate uptake in bacteria. Assays of β-galactosidase activity and real-time quantitative PCR showed that loss of ptsI caused a 70% reduction in sodA2 expression. The ΔptsI mutant also showed a 1000-fold reduction in colonization of wheat roots, as well as a reduced growth rate in minimal media with either glucose or succinate as the sole carbon source. Artificial induction of sodA2 in the ΔptsI mutant partially restored root colonizing ability and utilization of succinate, but not glucose. These results suggest that the PTS plays an important role in rhizosphere colonization by both promoting nutrient utilization and regulating sodA2 expression in B. cereus 905.
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Affiliation(s)
- Tantan Gao
- Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing 100193, China; Department of Biology, Northeastern University, 360 Huntington Avenue, Boston, MA 02215, USA
| | - Yan Li
- Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing 100193, China
| | - Mingzheng Ding
- Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing 100193, China
| | - Yunrong Chai
- Department of Biology, Northeastern University, 360 Huntington Avenue, Boston, MA 02215, USA.
| | - Qi Wang
- Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing 100193, China.
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Tanwar A, Chawla R, Ansari MM, Neha, Thakur P, Chakotiya AS, Goel R, Ojha H, Asif M, Basu M, Arora R, Khan HA. In vivo anti-arthritic efficacy of Camellia sinensis (L.) in collagen induced arthritis model. Biomed Pharmacother 2016; 87:92-101. [PMID: 28049097 DOI: 10.1016/j.biopha.2016.12.089] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Revised: 12/12/2016] [Accepted: 12/21/2016] [Indexed: 10/20/2022] Open
Abstract
BACKGROUND Rheumatoid arthritis (RA), an autoimmune inflammatory disorder with synovial hyperplasia, destruction of cartilage, bone damage is often associated with risk of infections. Such risk could be attributed towards usage of immunosuppressive agents. Thus, the present study was undertaken to evaluate the anti-arthritic efficacy of aquo-alcoholic extract of Camellia sinensis (L.). MATERIAL AND METHODS Dried leaves of Camellia sinensis (L.) or Cs were filtered and extracted in 1:1 aqueous: ethanol by Soxhlet apparatus followed by lyophilization and spray drying to develop amorphous powder. Four different oral doses (50, 100, 200, 400mg/kg/body wt.) of aquo-alcoholic extract were evaluated for anti-edematogenic effect in collagen induced arthritis model. The selected anti-arthritic doses of Cs were evaluated for the oxidative stress markers like Glutathione [5-5'dithio-bis-2-nitrobenzoicacid (DTNB)], Superoxide dismutase [Epinephrine], Catalase [Hydrogen peroxide], Lipid peroxidation [Thiobarbituric acid reactive substance (TBARS)], Nitric oxide [Griess reagents:Nitrobluetetrazolium], Articular elastase [N-methoxysuccinyl-Ala-Ala-Pro- Val p-nitroanilide] in joints followed by haematological evaluation including RBC, WBC, Haemoglobin, platelets and haematocrit. To validate these biochemical changes, the radiological and histopathological (Haematoxylin & Eosin) evaluation was also conducted. RESULTS The selected anti-arthritic dose of Cs i.e. 400mg/kg/body wt. (∼60% anti-arthritic efficacy on 35th day) could be attributed towards significant (p<0.05) increase in the levels of enzymatic (Superoxide dismutase and Catalase) and non-enzymatic (Glutathione) antioxidants by 34%, 59% and 50% respectively. Simultaneously, the significant (p<0.05) reduction of lipid peroxides, nitrite radical and elastase activity by 32%, 45% & 32% respectively as compare to control indicated overall decrease in oxidative stress. Haematological evaluation revealed restoration of RBC, WBC and platelets level in treatment group. The confirmatory analysis utilizing radiological and histological assessment showed alleviation of joint deformity, tissue swelling, pannus formation and neutrophils infiltration in treatment group as compared to collagen induced arthritis. CONCLUSION The analysis showed that Cs can play an effective role in reduction of oxidative stress by modulating levels of antioxidants, reducing levels of free radicals while restoring normal haematopoietic cascade as observed in collagen induced arthritis model. Thus, the cumulative dose impact of 400mg/kg body wt., over a period of 14days also found extremely effective in terms of safeguarding their structural conformity against such auto-immune disorder.
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Affiliation(s)
- Ankit Tanwar
- Heavy Metal and Clinical Toxicology Laboratory, Department of Medical Elementology and Toxicology, Hamdard University, Hamdard Nagar, New Delhi, 110062, India; Division of CBRN Defence, Institute of Nuclear Medicine and Allied Sciences, Delhi, India
| | - Raman Chawla
- Division of CBRN Defence, Institute of Nuclear Medicine and Allied Sciences, Delhi, India
| | - Md Meraj Ansari
- Heavy Metal and Clinical Toxicology Laboratory, Department of Medical Elementology and Toxicology, Hamdard University, Hamdard Nagar, New Delhi, 110062, India
| | - Neha
- Heavy Metal and Clinical Toxicology Laboratory, Department of Medical Elementology and Toxicology, Hamdard University, Hamdard Nagar, New Delhi, 110062, India
| | - Pallavi Thakur
- Division of CBRN Defence, Institute of Nuclear Medicine and Allied Sciences, Delhi, India
| | - Ankita Singh Chakotiya
- Division of CBRN Defence, Institute of Nuclear Medicine and Allied Sciences, Delhi, India
| | - Rajeev Goel
- Division of CBRN Defence, Institute of Nuclear Medicine and Allied Sciences, Delhi, India
| | - Himanshu Ojha
- Division of CBRN Defence, Institute of Nuclear Medicine and Allied Sciences, Delhi, India
| | - M Asif
- Faculty of Medicine (U), Hamdard University, Hamdard Nagar, New Delhi, 110062, India
| | - Mitra Basu
- Division of CBRN Defence, Institute of Nuclear Medicine and Allied Sciences, Delhi, India
| | - Rajesh Arora
- Office of DG (LS), Defence Research and Development Organisation, DRDO Bhawan, Delhi, India
| | - Haider Ali Khan
- Heavy Metal and Clinical Toxicology Laboratory, Department of Medical Elementology and Toxicology, Hamdard University, Hamdard Nagar, New Delhi, 110062, India.
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OxyR-regulated catalase CatB promotes the virulence in rice via detoxifying hydrogen peroxide in Xanthomonas oryzae pv. oryzae. BMC Microbiol 2016; 16:269. [PMID: 27825304 PMCID: PMC5101826 DOI: 10.1186/s12866-016-0887-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Accepted: 11/03/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND To facilitate infection, Xanthomonas oryzae pv. oryzae (Xoo), the bacterial blight pathogen of rice, needs to degrade hydrogen peroxide (H2O2) generated by the host defense response via a mechanism that is mediated by the transcriptional regulator OxyR. The catalase (CAT) gene catB has previously been shown to belong to the OxyR regulon in Xoo. However, its expression patterns and function in H2O2 detoxification and bacterial pathogenicity on rice remain to be elucidated. RESULTS The catB gene encodes a putative catalase and is highly conserved in the sequenced strains of Xanthomonas spp. β-galactosidase analysis and electrophoretic mobility shift assays (EMSA) showed that OxyR positively regulated the transcription of catB by directly binding to its promoter region. The quantitative real-time PCR (qRT-PCR) assays revealed that the expression levels of catB and oxyR were significantly induced by H2O2. Deletion of catB or oxyR drastically impaired bacterial viability in the presence of extracellular H2O2 and reduced CAT activity, demonstrating that CatB and OxyR contribute to H2O2 detoxification in Xoo. In addition, ΔcatB and ΔoxyR displayed shorter bacterial blight lesions and reduced bacterial growth in rice compared to the wild-type stain, indicating that CatB and OxyR play essential roles in the virulence of Xoo. CONCLUSIONS Transcription of catB is enhanced by OxyR in response to exogenous H2O2. CatB functions as an active catalase that is required for the full virulence of Xoo in rice.
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Thaweethawakorn A, Parks D, So JS, Chang WS. Role of the extracytoplasmic function sigma factor CarQ in oxidative response of Bradyrhizobium japonicum. J Microbiol 2015; 53:526-34. [PMID: 26224455 DOI: 10.1007/s12275-015-5308-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Revised: 07/17/2015] [Accepted: 07/21/2015] [Indexed: 12/11/2022]
Abstract
As a nitrogen-fixing bacterium, Bradyrhizobium japonicum can establish a symbiotic relationship with the soybean plant (Glycine max). To be a successful symbiont, B. japonicum must deal with plant defense responses, such as an oxidative burst. Our previous functional genomics study showed that carQ (bll1028) encoding extracytoplasmic function (ECF) sigma factor was highly expressed (107.8-fold induction) under oxidative stress. Little is known about the underlying mechanisms of how CarQ responds to oxidative stress. In this study, a carQ knock-out mutant was constructed using site-specific mutagenesis to identify the role of carQ in the oxidative response of B. japonicum. The carQ mutant showed a longer generation time than the wild type and exhibited significantly decreased survival at 10 mM H(2)O(2) for 10 min of exposure. Surprisingly, there was no significant difference in expression of oxidative stress-responsive genes such as katG and sod between the wild type and carQ mutant. The mutant also showed a significant increase in susceptibility to H(2)O(2) compared to the wild type in the zone inhibition assay. Nodulation phenotypes of the carQ mutant were distinguishable compared to those of the wild type, including lower numbers of nodules, decreased nodule dry weight, decreased plant dry weight, and a lower nitrogen fixation capability. Moreover, desiccation of mutant cells also resulted in significantly lower percent of survival in both early (after 4 h) and late (after 24 h) desiccation periods. Taken together, this information will provide an insight into the role of the ECF sigma factor in B. japonicum to deal with a plant-derived oxidative burst.
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Arafa MH, Mohamed DA, Atteia HH. Ameliorative effect of N-acetyl cysteine on alpha-cypermethrin-induced pulmonary toxicity in male rats. ENVIRONMENTAL TOXICOLOGY 2015; 30:26-43. [PMID: 23900960 DOI: 10.1002/tox.21891] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 06/22/2013] [Accepted: 06/26/2013] [Indexed: 06/02/2023]
Abstract
Alpha-cypermethrin (α-CYP) is one of the most widely used insecticides. It may become an air pollutant and adversely affect the health. The present study was designed to determine whether treatment with N-acetyl cysteine (NAC), a well-known antioxidant, can be useful for the management of the deleterious effects of α-CYP on lung tissues. For this purpose, thirty two male rats were divided into four different groups (eight rats for each). Group (I) gavaged with corn oil (control group), group (II) gavaged daily with NAC (150 mg kg(-1) body weight), group (III) gavaged with α-CYP (14.5 mg kg(-1) body weight/day, dissolved in corn oil), group (IV) gavaged with NAC then with α-CYP 2 h later for 12 weeks. α-CYP significantly increased serum lactate dehydrogenase (LDH) and pulmonary malondialdehyde (MDA) levels, while decreased the activities of catalase (CAT) and superoxide dismutase (SOD) as well as reduced glutathione (GSH) content in lung. It also provoked higher levels of serum nitric oxide (NO), lung interleukin-1 beta (IL-1β), tumor necrosis factor-alpha (TNF-α), hydroxyproline (Hyp) as well as heme oxygenase-1 (HO-1), inducible nitric oxide synthase (iNOS) and nuclear factor-kappa B (NF-К B) gene expression in lung tissues. Histopathological alterations in lung with congestion, cellular infiltration, necrotic changes and thickening of inter-alveolar septa were observed following α-CYP administration. NAC reduced the adverse effects of α-CYP on lung tissues and improved the histological architecture of lung since it showed antioxidant, anti-inflammatory and antifibrotic effects on lung tissues. Our results indicate that NAC exerts a potent protective effect against α-CYP-induced oxidative damage and inflammation in lung tissues.
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Affiliation(s)
- Manar Hamed Arafa
- Department of Forensic Medicine and Clinical Toxicology, Faculty of Medicine, Zagazig University, Zagazig, Sharkia Government, Egypt
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15
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Hong JK, Kang SR, Kim YH, Yoon DJ, Kim DH, Kim HJ, Sung CH, Kang HS, Choi CW, Kim SH, Kim YS. Hydrogen Peroxide- and Nitric Oxide-mediated Disease Control of Bacterial Wilt in Tomato Plants. THE PLANT PATHOLOGY JOURNAL 2013; 29:386-96. [PMID: 25288967 PMCID: PMC4174819 DOI: 10.5423/ppj.oa.04.2013.0043] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Revised: 08/21/2013] [Accepted: 08/23/2013] [Indexed: 05/10/2023]
Abstract
Reactive oxygen species (ROS) generation in tomato plants by Ralstonia solanacearum infection and the role of hydrogen peroxide (H2O2) and nitric oxide in tomato bacterial wilt control were demonstrated. During disease development of tomato bacterial wilt, accumulation of superoxide anion (O2 (-)) and H2O2 was observed and lipid peroxidation also occurred in the tomato leaf tissues. High doses of H2O2and sodium nitroprusside (SNP) nitric oxide donor showed phytotoxicity to detached tomato leaves 1 day after petiole feeding showing reduced fresh weight. Both H2O2and SNP have in vitro antibacterial activities against R. solanacearum in a dose-dependent manner, as well as plant protection in detached tomato leaves against bacterial wilt by 10(6) and 10(7) cfu/ml of R. solanacearum. H2O2- and SNP-mediated protection was also evaluated in pots using soil-drench treatment with the bacterial inoculation, and relative 'area under the disease progressive curve (AUDPC)' was calculated to compare disease protection by H2O2 and/or SNP with untreated control. Neither H2O2 nor SNP protect the tomato seedlings from the bacterial wilt, but H2O2+ SNP mixture significantly decreased disease severity with reduced relative AUDPC. These results suggest that H2O2 and SNP could be used together to control bacterial wilt in tomato plants as bactericidal agents.
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Affiliation(s)
- Jeum Kyu Hong
- Department of Horticultural Science, Gyeongnam National University of Science and Technology (GNTech), Jinju 660-758, Korea
| | - Su Ran Kang
- Department of Horticultural Science, Gyeongnam National University of Science and Technology (GNTech), Jinju 660-758, Korea
| | - Yeon Hwa Kim
- Department of Horticultural Science, Gyeongnam National University of Science and Technology (GNTech), Jinju 660-758, Korea
| | - Dong June Yoon
- Department of Horticultural Science, Gyeongnam National University of Science and Technology (GNTech), Jinju 660-758, Korea
| | - Do Hoon Kim
- Department of Horticultural Science, Gyeongnam National University of Science and Technology (GNTech), Jinju 660-758, Korea
| | - Hyeon Ji Kim
- Department of Horticultural Science, Gyeongnam National University of Science and Technology (GNTech), Jinju 660-758, Korea
| | - Chang Hyun Sung
- Department of Horticultural Science, Gyeongnam National University of Science and Technology (GNTech), Jinju 660-758, Korea
| | - Han Sol Kang
- Department of Horticultural Science, Gyeongnam National University of Science and Technology (GNTech), Jinju 660-758, Korea
| | - Chang Won Choi
- Department of Biology and Medical Science, Paichai University, Daejeon 302-735, Korea
| | - Seong Hwan Kim
- Department of Microbiology and Institute of Basic Sciences, Dankook University, Cheonan 330-714, Korea
| | - Young Shik Kim
- Department of Plant Science and Food Biotechnology, Sangmyung University, Cheonan 330-720, Korea
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Co3O4 nanoparticles as an efficient catalase mimic: Properties, mechanism and its electrocatalytic sensing application for hydrogen peroxide. ACTA ACUST UNITED AC 2013. [DOI: 10.1016/j.molcata.2013.05.016] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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17
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Hernandez-Marin E, Martínez A. Carbohydrates and their free radical scavenging capability: a theoretical study. J Phys Chem B 2012; 116:9668-75. [PMID: 22853004 DOI: 10.1021/jp304814r] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
A density functional theory (DFT) study on the free radical (OH(•) and OOH(•)) scavenging properties of some mono- and polysaccharides is presented. Two mechanisms, single electron transfer (SET) and hydrogen atom transfer (HAT), are considered. The former mechanism is studied by making use of the vertical ionization energy and vertical electron affinity of the radicals and carbohydrates. It is confirmed that the SET mechanism is not plausible to occur. With respect to the HAT, not only does the OH(•) radical react preferably with one hydrogen atom bonded to one carbon atom, but also the reaction with a hydrogen atom bonded to an oxygen is possible. Finally, it is suggested that the carbohydrates are not able to directly scavenge OOH(•).
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Affiliation(s)
- Elizabeth Hernandez-Marin
- Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Circuito Exterior s/n, C. U. P.O. Box 70-360, Coyoacán, 04510 México, DF México.
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18
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Förster F, Beisser D, Grohme MA, Liang C, Mali B, Siegl AM, Engelmann JC, Shkumatov AV, Schokraie E, Müller T, Schnölzer M, Schill RO, Frohme M, Dandekar T. Transcriptome analysis in tardigrade species reveals specific molecular pathways for stress adaptations. Bioinform Biol Insights 2012; 6:69-96. [PMID: 22563243 PMCID: PMC3342025 DOI: 10.4137/bbi.s9150] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Tardigrades have unique stress-adaptations that allow them to survive extremes of cold, heat, radiation and vacuum. To study this, encoded protein clusters and pathways from an ongoing transcriptome study on the tardigrade Milnesium tardigradum were analyzed using bioinformatics tools and compared to expressed sequence tags (ESTs) from Hypsibius dujardini, revealing major pathways involved in resistance against extreme environmental conditions. ESTs are available on the Tardigrade Workbench along with software and databank updates. Our analysis reveals that RNA stability motifs for M. tardigradum are different from typical motifs known from higher animals. M. tardigradum and H. dujardini protein clusters and conserved domains imply metabolic storage pathways for glycogen, glycolipids and specific secondary metabolism as well as stress response pathways (including heat shock proteins, bmh2, and specific repair pathways). Redox-, DNA-, stress- and protein protection pathways complement specific repair capabilities to achieve the strong robustness of M. tardigradum. These pathways are partly conserved in other animals and their manipulation could boost stress adaptation even in human cells. However, the unique combination of resistance and repair pathways make tardigrades and M. tardigradum in particular so highly stress resistant.
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Affiliation(s)
- Frank Förster
- Dept. of Bioinformatics, Biocenter University of Würzburg, 97074 Würzburg, Germany
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19
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Večeřa J, Krishnan N, Mithöfer A, Vogel H, Kodrík D. Adipokinetic hormone-induced antioxidant response in Spodoptera littoralis. Comp Biochem Physiol C Toxicol Pharmacol 2012; 155:389-95. [PMID: 22085825 DOI: 10.1016/j.cbpc.2011.10.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2011] [Revised: 10/31/2011] [Accepted: 10/31/2011] [Indexed: 11/29/2022]
Abstract
The antioxidative potential of the Manduca sexta adipokinetic hormone (Manse-AKH) in the last instar larvae of Spodoptera littoralis (Noctuidae, Lepidoptera) was demonstrated after exposure to oxidative stress (OS) elicited by feeding on artificial diet containing tannic acid (TA). Determination of protein carbonyls (PCs) and reduced glutathione (GSH) levels, monitoring of activity of antioxidant enzymes catalase (CAT), superoxide dismutase (SOD) and glutathione-S-transferases (GSTs), as well as measuring of the mRNA expression of CAT and SOD were used as markers of the OS. Injection of the Manse-AKH (5 pmol per individual) reversed the OS status by mitigation of PCs formation and by stimulation of glutathione-S-transferases (GSTs) activity. The CAT and SOD mRNA expression was significantly suppressed after the Manse-AKH injection while activity of these enzymes was not affected. These results indicate that diminishing of OS after the AKH injection might be a result of activation of specific enzymatic pathway possibly at the post-translational level rather than a direct effect on regulation of antioxidant marker genes at the transcriptional level.
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Affiliation(s)
- Josef Večeřa
- Institute of Entomology, Biology Centre, Academy of Sciences, Branišovská 31, České Budějovice 370 05, Czech Republic
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20
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Bucková M, Godocíková J, Zámocký M, Polek B. Isolates of Comamonas spp. exhibiting catalase and peroxidase activities and diversity of their responses to oxidative stress. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2010; 73:1511-1516. [PMID: 20678795 DOI: 10.1016/j.ecoenv.2010.07.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2009] [Revised: 02/11/2010] [Accepted: 07/09/2010] [Indexed: 05/29/2023]
Abstract
For survival isolates of Comamonas testosteroni CCM 1931, C. testosteroni K3, C. terrigena N3H or N1C and C. terrigena CCM 2409, selected largely from polluted environments, the production of catalase and dianisidine-peroxidase activity was important. Electrophoretic resolution of cell-free extracts of aerobically grown strains in Luria-Bertani medium during the exponential phase revealed distinctive expression of catalatic and peroxidatic activities detected with 3,3'-diaminobenzidine tetrahydrochloride (DAB). The protection of isolates from 20 or 40 mM H(2)O(2) stress was characterized with a considerable diversity in catalase and peroxidase responses that resulted from hydroperoxidase's variant of original isolates, indicating also a selective pressure of environment. Results indicate catalase to be important for adaptation of cultures to high concentration of 60mM H(2)O(2). The greatest appreciable differences in sensitivity to toxic effect of H(2)O(2) (20 or 40 mM) treatment between individual isolates and their adapted variants during the growth were observed until the middle of exponential phase. Isolates exhibited diversity in catalases responses to possible contaminants o-or p-phenylenediamine (PDA) as well. Only positional isomer p-PDA (1 or 2mM) stimulated catalase activity unlike from isomer o-PDA in C. terrigena N3H cells. The study can contribute to understanding of bacterial antioxidative enzymatic responses in the presence of possible physiological stress resulting mainly from environmental pollutants.
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Affiliation(s)
- Mária Bucková
- Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, SK-84551, Bratislava, Slovakia
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21
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Hu YQ, Liu S, Yuan HM, Li J, Yan DW, Zhang JF, Lu YT. Functional comparison of catalase genes in the elimination of photorespiratory H2O2 using promoter- and 3'-untranslated region exchange experiments in the Arabidopsis cat2 photorespiratory mutant. PLANT, CELL & ENVIRONMENT 2010; 33:1656-1670. [PMID: 20492555 DOI: 10.1111/j.1365-3040.2010.02171.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Photorespiration-associated production of H(2) O(2) accounts for the majority of total H(2) O(2) in leaves of C(3) plants and is mainly eliminated by catalases. In Arabidopsis, lack of CAT2, but not CAT1 or CAT3, results in growth suppression and a marked accumulation of H(2) O(2) in leaves. To evaluate the contribution of individual catalase genes and their promoters to catalase function, we investigated the growth suppression and H(2) O(2) accumulation phenotypes of Arabidopsis derivatives expressing catalase genes from heterologous CAT promoters in a cat2 mutant background. The expression of CAT2 from the CAT2 promoter restored the wild-type phenotype in a cat2-1 mutant, while CAT1 and CAT3 promoter-driven expression of CAT2 did not. Ectopic expression of CAT3 from the CAT2 promoter also restored the normal phenotype, unlike that of CAT1 which required replacement of the CAT1 3'-untranslated region (UTR) with that of CAT2. These results demonstrated that the photorespiratory role of CAT2 is determined mainly by the regulation of its promoter activity. The 3'-UTR of CAT2 was vital for controlling CAT2 protein levels under photorespiratory conditions. Identification of component of heterotetramers catalase isoforms suggested that there is some functional redundancy between CAT2 and CAT1 and CAT3.
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Affiliation(s)
- Ye-Qin Hu
- Key Lab of MOE for Plant Developmental Biology, College of Life Sciences, Wuhan University, Wuhan 430072, China
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22
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Bucková M, Godocíková J, Zámocký M, Polek B. Screening of bacterial isolates from polluted soils exhibiting catalase and peroxidase activity and diversity of their responses to oxidative stress. Curr Microbiol 2010; 61:241-7. [PMID: 20145932 DOI: 10.1007/s00284-010-9601-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2009] [Accepted: 01/27/2010] [Indexed: 11/27/2022]
Abstract
For the survival of individual isolates of gram-negative bacteria Pseudomonas putida, Achromobacter xylosoxidans, and the gram-positive bacterium Bacillus megaterium, in an environment polluted with crude oil products, the production of catalases exhibiting both catalase and dianisidine-peroxidase activity is important. Electrophoretic resolution of cell-free extracts of aerobically grown strains in Luria-Bertani medium during exponential phase revealed distinctive expression of catalatic and peroxidatic activities detected with 3,3'-diaminobenzidine tetrahydrochloride. A considerable diversity in microbial catalase and peroxidase responses to 20 or 40 mM H(2)O(2) stress, resulted from hydroperoxidase's variant of original isolates, indicating an environmental selective pressure. However, catalase was important for the adaptation of cultures to high concentration of 60 mM H(2)O(2). Appreciable differences in the sensitivity to toxic effect of H(2)O(2) (20 or 40 mM) treatment between individual isolates and their adapted variants during growth were observed until the middle of exponential phase, but they were insignificant at the entry to stationary phase. Isolates also exhibited a considerable diversity in catalases responses to phenolic contaminants 1 and 2 mM o- or p-phenylenediamine. Catalase activity of bacterium P. putida was visibly stimulated only by p-phenylenediamine and not by its positional isomer o-PDA. This study contributes to a better understanding of the role catalases play in bacterial responses to a polluted environment.
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Affiliation(s)
- Mária Bucková
- Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, 84551 Bratislava, Slovakia
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23
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Shao T, Yuan H, Yan B, Lü Z, Min H. Antioxidant enzyme activity in bacterial resistance to nicotine toxicity by reactive oxygen species. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2009; 57:456-462. [PMID: 19294456 DOI: 10.1007/s00244-009-9305-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2008] [Accepted: 02/24/2009] [Indexed: 05/27/2023]
Abstract
We analyzed superoxide dismutase (SOD), catalase (CAT), and ATPase activities in the highly nicotine-degrading strain Pseudomonas sp. HF-1 and two standard strains Escherichia coli and Bacillus subtilis in an attempt to understand antioxidant enzymes in bacteria are produced in response to nicotine, which increases the virulence of the bacteria. Nicotine had different effects on different antioxidant enzymes of different bacteria. SOD plays a more important role in resistance to nicotine stress in E. coli than it does in CAT. Multiple antioxidant enzymes are involved in combating oxidative stress caused by nicotine in Pseudomonas sp. HF-1. The contribution of a particular antioxidant enzyme for protection from nicotine stress varies with the growth phase involved. The inhibition of ATPase in Pseudomonas sp. HF-1 at the stationary phase was enhanced with increasing nicotine concentration, showing a striking dose-response relationship. Nicotine probably affected the metabolism of ATP to some extent. Furthermore, different bacteria possessed distinct SOD isoforms to cope with oxidative stress caused by nicotine.
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Affiliation(s)
- Tiejuan Shao
- College of Life Science, Zhejiang University, Zi Jin Gang Campus, Hangzhou 310058, People's Republic of China
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24
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Flores-Cruz Z, Allen C. Ralstonia solanacearum encounters an oxidative environment during tomato infection. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2009; 22:773-82. [PMID: 19522559 DOI: 10.1094/mpmi-22-7-0773] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Ralstonia solanacearum genes that are induced during tomato infection suggested that this pathogen encounters reactive oxygen species (ROS) during bacterial wilt pathogenesis. The genomes of R. solanacearum contain multiple redundant ROS-scavenging enzymes, indirect evidence that this pathogen experiences intense oxidative stress during its life cycle. Over 9% of the bacterium's plant-induced genes were also upregulated by hydrogen peroxide in culture, suggesting that oxidative stress may be linked to life in the plant host. Tomato leaves infected by R. solanacearum contained hydrogen peroxide, and concentrations of this ROS increased as pathogen populations increased. Mutagenesis of a plant-induced predicted peroxidase gene, bcp, resulted in an R. solanacearum strain with reduced ability to detoxify ROS in culture. The bcp mutant caused slightly delayed bacterial wilt disease onset in tomato. Moreover, its virulence was significantly reduced on tobacco plants engineered to overproduce hydrogen peroxide, demonstrating that Bcp is necessary for detoxification of plant-derived hydrogen peroxide and providing evidence that host ROS can limit the success of this pathogen. These results reveal that R. solanacearum is exposed to ROS during pathogenesis and that it has evolved a redundant and efficient oxidative stress response to adapt to the host environment and cause disease.
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Affiliation(s)
- Zomary Flores-Cruz
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI 53706, USA
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25
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Castro-Mercado E, Martinez-Diaz Y, Roman-Tehandon N, Garcia-Pineda E. Biochemical analysis of reactive oxygen species production and antioxidative responses in unripe avocado (Persea americana Mill var Hass) fruits in response to wounding. PROTOPLASMA 2009; 235:67-76. [PMID: 19234667 DOI: 10.1007/s00709-009-0034-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2008] [Accepted: 01/20/2009] [Indexed: 05/27/2023]
Abstract
We analyzed the production of reactive oxygen species (ROS) and of detoxifying enzymes and enzymes of the ascorbate (ASC) acid cycle in avocado fruit (Pesea Americana Mill cv Hass) in response to wounding. The levels of superoxide anion (O(2-), hydroxyl radicals (OH.) and hydrogen peroxide (H(2)O(2)) increased at 15 min and 2 and 15 h post-wounding. Peroxidase (POD) activity had increased to high levels 24 h after wounding; in contrast, catalase and superoxide dismutase (SOD) levels hat decreased significantly at 24 h post-treatment. Basic POD was the major POD form induced, and the levels of at least three apoplastic POD isozymes -increased following wounding. Using specific inhibitors, we characterized one MnSOD and two CuZnSOD isozymes. CuZnSOD activities decreased notably 12 h after treatment. The activities of dehydroascorbate reductase and glutathione reductase increased dramatically following the wounding treatment, possibly as a means to compensate for the redox changes due to ROS production.
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Affiliation(s)
- E Castro-Mercado
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. B1, C.P. 58040, Morelia, Mexico
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Schulte C, Arenskötter M, Berekaa MM, Arenskötter Q, Priefert H, Steinbüchel A. Possible involvement of an extracellular superoxide dismutase (SodA) as a radical scavenger in poly(cis-1,4-isoprene) degradation. Appl Environ Microbiol 2008; 74:7643-53. [PMID: 18952871 PMCID: PMC2607186 DOI: 10.1128/aem.01490-08] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2008] [Accepted: 10/20/2008] [Indexed: 11/20/2022] Open
Abstract
Gordonia westfalica Kb1 and Gordonia polyisoprenivorans VH2 induce the formation of an extracellular superoxide dismutase (SOD) during poly(cis-1,4-isoprene) degradation. To investigate the function of this enzyme in G. polyisoprenivorans VH2, the sodA gene was disrupted. The mutants exhibited reduced growth in liquid mineral salt media containing poly(cis-1,4-isoprene) as the sole carbon and energy source, and no SOD activity was detectable in the supernatants of the cultures. Growth experiments revealed that SodA activity is required for optimal growth on poly(cis-1,4-isoprene), whereas this enzyme has no effect on aerobic growth in the presence of water-soluble substrates like succinate, acetate, and propionate. This was detected by activity staining, and proof of expression was by antibody detection of SOD. When SodA from G. westfalica Kb1 was heterologously expressed in the sodA sodB double mutant Escherichia coli QC779, the recombinant mutant exhibited increased resistance to paraquat, thereby indicating the functionality of the G. westfalica Kb1 SodA and indirectly protection of G. westfalica cells by SodA from oxidative damage. Both sodA from G. polyisoprenivorans VH2 and sodA from G. westfalica Kb1 coded for polypeptides comprising 209 amino acids and having approximately 90% and 70% identical amino acids, respectively, to the SodA from Mycobacterium smegmatis strain MC(2) 155 and Micrococcus luteus NCTC 2665. As revealed by activity staining experiments with the wild type and the disruption mutant of G. polyisoprenivorans, this bacterium harbors only one active SOD belonging to the manganese family. The N-terminal sequences of the extracellular SodA proteins of both Gordonia species showed no evidence of leader peptides for the mature proteins, like the intracellular SodA protein of G. polyisoprenivorans VH2, which was purified under native conditions from the cells. In G. westfalica Kb1 and G. polyisoprenivorans VH2, SodA probably provides protection against reactive oxygen intermediates which occur during degradation of poly(cis-1,4-isoprene).
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Affiliation(s)
- Carina Schulte
- Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, Correnstrasse 3, D-48149 Münster, Germany
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Dimitrieva GY, Crawford RL, Yüksel GU. The nature of plant growth-promoting effects of a pseudoalteromonad associated with the marine algae Laminaria japonica and linked to catalase excretion. J Appl Microbiol 2006; 100:1159-69. [PMID: 16703683 DOI: 10.1111/j.1365-2672.2006.02831.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS The goal of this study was to identify a marine algae-associated bacterium isolated from Laminaria japonica and investigate this microorganism's growth-promoting effects on plants. METHODS AND RESULTS The bacterium, identified as Pseudoalteromonas porphyrae, was determined to display a biostimulatory activity for seed germination and shoot growth in several agricultural plants and also for growth in ginseng callus cell culture. This biostimulatory activity was linked to a catalase enzyme that was excreted in the maximal amount during the transition from logarithmic growth phase to stationary growth phase. In addition, selected shifts in growth temperature and medium salinity affected the amount of enzyme excreted. The purified catalase was determined to be composed of identical subunits. The catalase of interest displayed significantly higher biostimulatory activity than the catalase from bovine liver. CONCLUSIONS The catalase investigated in this study is unique in that it promotes growth in and possibly contributes to stress tolerance of plants. SIGNIFICANCE AND IMPACT OF THE STUDY The catalase of interest has the potential for use in treatments that aim to improve percent seed germination as well as obtaining tall shoots in a shorter time period.
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Affiliation(s)
- G Y Dimitrieva
- Department of Food Science and Toxicology, University of Idaho, Moscow, ID 83844-2312, USA
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28
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Godocíková J, Bohácová V, Zámocký M, Polek B. Production of catalases by Comamonas spp. and resistance to oxidative stress. Folia Microbiol (Praha) 2005; 50:113-8. [PMID: 16110914 DOI: 10.1007/bf02931458] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Bacterial isolates Comamonas terrigena N3H (from soil contaminated with crude oil) and C. testosteroni (isolated from the sludge of a wastewater treatment plant), exhibit much higher total catalase activity than the same species from laboratory collection cultures. Electrophoretic resolution of catalases revealed only one corresponding band in cell-free extracts of both C. testosteroni cultures. Isolates of C. terrigena N3H exhibited catalase-1 and catalase-2 activity, whereas in the collection culture C. terrigena ATCC 8461 only catalase-1 was detected. The environmental isolates exhibited much higher resistance to exogenous H2O2 (20, 40 mmol/L) than collection cultures, mainly in the middle and late exponential growth phases. The stepwise H2O2-adapted culture of C. terrigena N3H, which was more resistant to oxidative stress than the original isolate, exhibited an increase of catalase and peroxidase activity represented by catalase-1. Pretreatment of cells with 0.5 mmol/L H2O2 followed by an application of the oxidative agent in toxic concentrations (up to 40 mmol/L) increased the rate of cell survival in the original isolate, but not in the H2O2-adapted variant. The protection of bacteria caused by such pretreatment corresponded with stimulation of catalase activity in pretreated culture.
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Affiliation(s)
- J Godocíková
- Institute of Molecular Biology, Centre of Excellence, Slovak Academy of Sciences, 845 51 Bratislava, Slovakia.
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29
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Vattanaviboon P, Seeanukun C, Whangsuk W, Utamapongchai S, Mongkolsuk S. Important role for methionine sulfoxide reductase in the oxidative stress response of Xanthomonas campestris pv. phaseoli. J Bacteriol 2005; 187:5831-6. [PMID: 16077131 PMCID: PMC1196060 DOI: 10.1128/jb.187.16.5831-5836.2005] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
A methionine sulfoxide reductase gene (msrA) from Xanthomonas campestris pv. phaseoli has unique expression patterns and physiological function. msrA expression is growth dependent and is highly induced by exposure to oxidants and N-ethylmaleimide in an OxyR- and OhrR-independent manner. An msrA mutant showed increased sensitivity to oxidants but only during stationary phase.
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Affiliation(s)
- Paiboon Vattanaviboon
- Laboratory of Biotechnology, Chulabhorn Research Institute, Lak Si, Bangkok 10210, Thailand.
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30
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Morkunas I, Bednarski W, Kozłowska M. Response of embryo axes of germinating seeds of yellow lupine to Fusarium oxysporum. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2004; 42:493-499. [PMID: 15246062 DOI: 10.1016/j.plaphy.2004.05.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2004] [Accepted: 05/10/2004] [Indexed: 05/24/2023]
Abstract
Defence responses of embryo axes of Lupinus luteus L. cv. Polo were studied 48-96 h after inoculation with Fusarium oxysporum Schlecht f.sp. lupini. The infection restricted the growth of embryo axes, the lengths of infected embryo axes 72 and 96 h after inoculation were 11 and 12 mm less in the controls, respectively, while their masses c. 0.03 g less than in the controls. The concentration of H2O2 in embryo axes of inoculated germinating seeds was higher than in the control. This was probably a consequence of oxidative burst as well as H2O2 generation by the invading necrotrophic fungal pathogen. EPR-based analyses detected the presence of free radicals with g1 and g2 values of 2.0052 +/- 0.0004 and 2.0031 +/- 0.0005, respectively. Concentrations of the radicals 72 and 96 h after inoculation were 50% higher than in the control. The values of the spectroscopic splitting coefficients suggest that they are quinone radicals. However, inoculated embryo axes possess a number of adaptive mechanisms protecting them from oxidative damage. A twofold increase in catalase (CAT, EC 1.11.1.6) activity was evidenced in embryo axes infected with F. oxysporum Schlecht f. sp. lupini, as compared to the control 48-96 h after inoculation. Superoxide dismutase (SOD, EC 1.15.1.1) activity 96 h after inoculation was 80% higher than in the control. Furthermore, EPR-based analyses revealed a higher concentration of Mn2+ ions after 72 h for inoculated embryo axes, as compared to the control. On the other hand, no increase was detected in the concentration of thiobarbituric acid reactive substances (products of lipid peroxidation) in infected embryo axes. The protective mechanisms induced in lupine embryo axes in response to F. oxysporum Schlecht f.sp. lupini were compared with responses to infections with pathogenic fungi elicited in other plant families.
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Affiliation(s)
- Iwona Morkunas
- Department of Plant Physiology, August Cieszkowski Agricultural University, Wołyńska 35, 60-637 Poznań, Poland.
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31
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Testerman TL, Vazquez-Torres A, Xu Y, Jones-Carson J, Libby SJ, Fang FC. The alternative sigma factor sigmaE controls antioxidant defences required for Salmonella virulence and stationary-phase survival. Mol Microbiol 2002; 43:771-82. [PMID: 11929531 DOI: 10.1046/j.1365-2958.2002.02787.x] [Citation(s) in RCA: 143] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Bacteria must contend with conditions of nutrient limitation in all natural environments. Complex programmes of gene expression, controlled in part by the alternative sigma factors sigmaS (sigma38, RpoS) and sigmaH (sigma32, RpoH), allow a number of bacterial species to survive conditions of partial or complete starvation. We show here that the alternative sigma factor sigmaE (sigma24, RpoE) also facilitates the survival of Salmonella typhimurium under conditions of nutrient deprivation. Expression of the sigmaE regulon is strongly induced upon entry of Salmonella into stationary phase. A Salmonella mutant lacking sigmaE has reduced survival during stationary phase as well as increased susceptibility to oxidative stress. A Salmonella strain lacking both sigmaE and sigmaS is non-viable after just 24 h in stationary phase, but survival of these mutants is completely preserved under anaerobic stationary-phase conditions, suggesting that oxidative injury is one of the major mechanisms of reduced microbial viability during periods of nutrient deprivation. Moreover, the attenuated virulence of sigmaE-deficient Salmonella for mice can be largely restored by genetic abrogation of the host phagocyte respiratory burst, suggesting that the sigmaE regulon plays an important antioxidant role during Salmonella infection of mammalian hosts.
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Affiliation(s)
- Traci L Testerman
- Department of Medicine, University of Colorado Health Sciences Center, Denver, CO 80262, USA
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32
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Muckenschnabel I, Goodman BA, Williamson B, Lyon GD, Deighton N. Infection of leaves of Arabidopsis thaliana by Botrytis cinerea: changes in ascorbic acid, free radicals and lipid peroxidation products. JOURNAL OF EXPERIMENTAL BOTANY 2002; 53:207-214. [PMID: 11807124 DOI: 10.1093/jexbot/53.367.207] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Infection of leaves of Arabidopsis thaliana with conidial suspensions of the necrotrophic pathogen Botrytis cinerea resulted in a large decrease in the level of ascorbic acid and increases in intensity of a single-peak free radical and Fe(III) (g=4.27) signals in electron paramagnetic resonance (EPR) spectra. These changes were not confined to the spreading lesions or associated areas of chlorosis, but extended to other apparently healthy tissues in the infected leaves. They are, therefore, consistent with the existence of high levels of oxidative stress being generated as a result of the infection process. The expected accompanying increases in levels of the aldehydic products of lipid peroxidation, malondialdehyde (MDA) and 4-hydroxy-2-nonenal (4-HNE), were not observed, and in the case of MDA the levels in tissue from infected plants were appreciably lower than in the healthy controls. These last findings are surprising and demonstrate a difference in the response of A. thaliana to infection with B. cinerea compared with tissues from other plant families studied previously.
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Affiliation(s)
- I Muckenschnabel
- Scottish Crop Research Institute, Invergowrie, Dundee DD2 5DA, Scotland, UK
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33
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Xu XQ, Li LP, Pan SQ. Feedback regulation of an Agrobacterium catalase gene katA involved in Agrobacterium-plant interaction. Mol Microbiol 2001; 42:645-57. [PMID: 11722732 DOI: 10.1046/j.1365-2958.2001.02653.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Catalases are known to detoxify H2O2, a major component of oxidative stress imposed on a cell. An Agrobacterium tumefaciens catalase encoded by a chromosomal gene katA has been implicated as an important virulence factor as it is involved in detoxification of H2O2 released during Agrobacterium-plant interaction. In this paper, we report a feedback regulation pathway that controls the expression of katA in A. tumefaciens cells. We observed that katA could be induced by plant tissue sections and by acidic pH on a minimal medium, which resembles the plant environment that the bacteria encounter during the course of infection. This represents a new regulatory factor for catalase induction in bacteria. More importantly, a feedback regulation was observed when the katA-gfp expression was studied in different genetic backgrounds. We found that introduction of a wild-type katA gene encoding a functional catalase into A. tumefaciens cells could repress the katA-gfp expression over 60-fold. The katA gene could be induced by H2O2 and the encoded catalase could detoxify H2O2. In addition, the katA-gfp expression of one bacterial cell could be repressed by other surrounding catalase-proficient bacterial cells. Furthermore, mutation at katA caused a 10-fold increase of the intracellular H2O2 concentration in the bacteria grown on an acidic pH medium. These results suggest that the endogenous H2O2 generated during A. tumefaciens cell growth could serve as the intracellular and intercellular inducer for the katA gene expression and that the acidic pH could pose an oxidative stress on the bacteria. Surprisingly, one mutated KatA protein, exhibiting no significant catalase activity as a result of the alteration of two important residues at the putative active site, could partially repress the katA-gfp expression. The feedback regulation of the katA gene by both catalase activity and KatA protein could presumably maintain an appropriated level of catalase activity and H2O2 inside A. tumefaciens cells.
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Affiliation(s)
- X Q Xu
- Department of Biological Sciences, National University of Singapore, Singapore 117543
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34
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Atichartpongkul S, Loprasert S, Vattanaviboon P, Whangsuk W, Helmann JD, Mongkolsuk S. Bacterial Ohr and OsmC paralogues define two protein families with distinct functions and patterns of expression. MICROBIOLOGY (READING, ENGLAND) 2001; 147:1775-1782. [PMID: 11429455 DOI: 10.1099/00221287-147-7-1775] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Xanthomonas campestris Ohr (a protein involved in organic peroxide protection) and Escherichia coli OsmC (an osmotically inducible protein of unknown function) are related proteins. Database searches and phylogenetic analyses reveal that Ohr and OsmC homologues cluster into two related subfamilies of proteins widely distributed in both Gram-negative and Gram-positive bacteria. To determine if these two subfamilies are functionally distinct, ohr and osmC in Pseudomonas aeruginosa (a bacterium with one representative from each subfamily) were analysed. Only ohr mutants are hypersensitive to organic peroxide, and this phenotype can be restored by complementation with ohr but not osmC. In addition, expression of ohr was highly induced only by organic peroxides, and not by other oxidants or stresses. In contrast, osmC was induced by ethanol and osmotic stress. A similar pattern of regulation was observed for Ohr and OsmC homologues in the Gram-positive bacterium Deinococcus radiodurans, though uninduced expression was much higher and induction lower in this species. These data clearly support the conclusion that Ohr and OsmC define two functionally distinct subfamilies with distinct patterns of regulation.
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Affiliation(s)
- Sopapan Atichartpongkul
- Laboratory of Biotechnology, Chulabhorn Research Institute, Lak Si, Bangkok 10210, Thailand1
| | - Suvit Loprasert
- Laboratory of Biotechnology, Chulabhorn Research Institute, Lak Si, Bangkok 10210, Thailand1
| | - Paiboon Vattanaviboon
- Laboratory of Biotechnology, Chulabhorn Research Institute, Lak Si, Bangkok 10210, Thailand1
| | - Wirongrong Whangsuk
- Laboratory of Biotechnology, Chulabhorn Research Institute, Lak Si, Bangkok 10210, Thailand1
| | - John D Helmann
- Department of Microbiology, Wing Hall, Cornell University, Ithaca, NY 14853-8101, USA3
| | - Skorn Mongkolsuk
- Department of Biotechnology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand2
- Laboratory of Biotechnology, Chulabhorn Research Institute, Lak Si, Bangkok 10210, Thailand1
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35
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Peters M, Heinaru A, Nurk A. Plasmid-encoded catalase KatA, the main catalase of Pseudomonas fluorescens strain Cb36. FEMS Microbiol Lett 2001; 200:235-40. [PMID: 11425481 DOI: 10.1111/j.1574-6968.2001.tb10721.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The plasmid-state catalase gene katA of the phenol gradative Pseudomonas fluorescens isolate Cb36 has been characterized and shown to be the major catalase of this strain. The predicted amino acid sequence of KatA revealed significant similarity with the catalase sequence from Neisseria meningitidis and has probably the non-pseudomonad origin. The specific activity of catalase was investigated and elevated catalase activity was found in stationary phase cells. The consensus sequence for promoters recognized by the stationary phase sigma factor sigma(s) was found 212 bp upstream of the putative ATG start codon. The ability of KatA to detoxify a high concentration of hydrogen peroxide and protect Pseudomonas putida and Escherichia coli cells was shown.
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Affiliation(s)
- M Peters
- Department of Genetics, Institute of Molecular and Cell Biology at University of Tartu and Estonian Biocentre.
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36
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Vattanaviboon P, Sriprang R, Mongkolsuk S. Catalase has a novel protective role against electrophile killing of Xanthomonas. MICROBIOLOGY (READING, ENGLAND) 2001; 147:491-498. [PMID: 11158366 DOI: 10.1099/00221287-147-2-491] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The ability of XANTHOMONAS: campestris pv. phaseoli to protect itself against lethal concentrations of man-made (N:-ethylmaleimide, NEM) and endogenously produced (methylglyoxal, MG) electrophiles was investigated. Pretreatment of X. c. pv. phaseoli with a low concentration of NEM induced protection against lethal concentrations of NEM and MG. MG pretreatment weakly induced protection against NEM but not against MG itself. NEM-induced protection against electrophile killing required new protein synthesis and was abolished by the addition of a protein synthesis inhibitor. By contrast, MG-induced protection against NEM killing was independent of de novo protein synthesis. X. c. pv. phaseoli harbouring an expression vector carrying a catalase gene was over 100-fold more resistant to MG and NEM killing. High expression levels of genes for other peroxide-protective enzymes, such as those for alkyl hydroperoxide reductase (ahpC and ahpF) and ohr, failed to protect against electrophile killing. Thus, catalase appears to have a novel protective role(s) against electrophile toxicity. This finding suggests that in X. c. pv. phaseoli NEM and MG toxicity might involve accumulation and/or increased production of H(2)O(2). This idea was supported by the observation that addition of 10 mM sodium pyruvate, a compound that can react chemically with peroxide or hydroxyl radical scavengers (DMSO and glycerol), was found to protect XANTHOMONAS: from electrophile killing. The protective role of catalase and the role of H(2)O(2) in electrophile toxicity are novel observations and could be generally important in other bacteria. In addition, unlike other bacteria, XANTHOMONAS: in stationary phase was more susceptible to electrophile killing compared to cells in exponential phase.
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Affiliation(s)
- Paiboon Vattanaviboon
- Laboratory of Biotechnology, Chulabhorn Research Institute, Lak Si, Bangkok 10210, Thailand1
| | - Rutchadaporn Sriprang
- Department of Biotechnology, Faculty of Science, Mahidol University, Rama 6 Rd, Bangkok 10400, Thailand2
| | - Skorn Mongkolsuk
- Department of Biotechnology, Faculty of Science, Mahidol University, Rama 6 Rd, Bangkok 10400, Thailand2
- Laboratory of Biotechnology, Chulabhorn Research Institute, Lak Si, Bangkok 10210, Thailand1
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Loprasert S, Fuangthong M, Whangsuk W, Atichartpongkul S, Mongkolsuk S. Molecular and physiological analysis of an OxyR-regulated ahpC promoter in Xanthomonas campestris pv. phaseoli. Mol Microbiol 2000; 37:1504-14. [PMID: 10998180 DOI: 10.1046/j.1365-2958.2000.02107.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In Xanthomonas campestris pv. phaseoli, a gene for the alkyl hydroperoxide reductase subunit C (ahpC) had unique patterns of regulation by various forms of OxyR. Reduced OxyR repressed expression of the gene, whereas oxidized OxyR activated its expression. This dual regulation of ahpC is unique and unlike all other OxyR-regulated genes. The ahpC transcription start site was determined. Analysis of the region upstream of the site revealed promoter sequences that had high homology to the Xanthomonas consensus promoter sequence. Data from gel shift experiments indicated that both reduced and oxidized OxyR could bind to the ahpC regulatory region. Moreover, the reduced and the oxidized forms of OxyR gave different DNase I footprint patterns, indicating that they bound to different sites. The oxidized OxyR binding site overlapped the -35 region of the ahpC promoter by a few bases. This position is consistent with the role of the protein in activating transcription of the gene. Binding of reduced OxyR to the ahpC promoter showed an extended DNase I footprint and DNase I hypersensitive sites, suggesting that binding of the protein caused a shift in the binding site and bending of the target DNA. In addition, binding of reduced OxyR completely blocked the -35 region of the ahpC promoter and prevented binding of RNA polymerase, leading to repression of the gene. Monitoring of the ahpC promoter activity in vivo confirmed the location of the oxidized OxyR binding site required for activation of the promoter. A mutant that separated OxyR regulation from basal ahpC promoter activity was constructed. The mutant was unable to respond to oxidants by increasing ahpC expression. Physiologically, it had a slower aerobic growth rate and was more sensitive to organic peroxide killing. This indicated that oxidant induction of ahpC has important physiological roles in normal growth and during oxidative stress.
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Affiliation(s)
- S Loprasert
- Laboratory of Biotechnology, Chulabhorn Research Institute, Lak Si, Bangkok 10210, Thailand
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38
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Sriprang R, Vattanaviboon P, Mongkolsuk S. Exposure of phytopathogenic Xanthomonas spp. to lethal concentrations of multiple oxidants affects bacterial survival in a complex manner. Appl Environ Microbiol 2000; 66:4017-21. [PMID: 10966423 PMCID: PMC92253 DOI: 10.1128/aem.66.9.4017-4021.2000] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
During plant-microbe interactions and in the environment, Xanthomonas campestris pv. phaseoli is likely to be exposed to high concentrations of multiple oxidants. Here, we show that simultaneous exposures of the bacteria to multiple oxidants affects cell survival in a complex manner. A superoxide generator (menadione) enhanced the lethal effect of an organic peroxide (tert-butyl hydroperoxide) by 1, 000-fold; conversely, treatment of cells with menadione plus H(2)O(2) resulted in 100-fold protection compared to that for cells treated with the individual oxidants. Treatment of X. campestris with a combination of H(2)O(2) and tert-butyl hydroperoxide elicited no additive or protective effect. High levels of catalase alone are sufficient to protect cells against the lethal effect of menadione plus H(2)O(2) and tert-butyl hydroperoxide plus H(2)O(2). These data suggest that H(2)O(2) is the lethal agent responsible for killing the bacteria as a result of these treatments. However, increased expression of individual genes for peroxide (alkyl hydroperoxide reductase, catalase)- and superoxide (superoxide dismutase)-scavenging enzymes or concerted induction of oxidative stress-protective genes by menadione gave no protection against killing by a combination of menadione plus tert-butyl hydroperoxide. However, X. campestris cells in the stationary phase and a spontaneous H(2)O(2)-resistant mutant (X. campestris pv. phaseoli HR) were more resistant to killing by menadione plus tert-butyl hydroperoxide. These findings give new insight into oxidant killing of Xanthomonas spp. that could be generally applied to other bacteria.
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Affiliation(s)
- R Sriprang
- Department of Biotechnology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand
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39
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Vattanaviboon P, Mongkolsuk S. Expression analysis and characterization of the mutant of a growth-phase- and starvation-regulated monofunctional catalase gene from Xanthomonas campestris pv. phaseoli. Gene 2000; 241:259-65. [PMID: 10675038 DOI: 10.1016/s0378-1119(99)00483-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Analysis of the Xanthomonas campestris pv. phaseoli (Xp) catalase profile using an activity gel revealed at least two distinct monofunctional catalase isozymes denoted Kat1 and Kat2. Kat1 was expressed throughout growth, whereas Kat2 was expressed only during the stationary phase of growth. The nucleotide sequence of a previously isolated monofunctional catalase gene, Xp katE, was determined. The deduced amino acid sequence of Xp KatE showed a high percentage identity to an atypical group of monofunctional catalases that includes the well-characterized E. coli katE. Expression of Xp katE was growth phase-dependent but was not inducible by oxidants. In addition, growth of Xp in a carbon-starvation medium induced expression of the gene. An Xp katE mutant was constructed, and analysis of its catalase enzyme pattern showed that Xp katE coded for the Kat2 isozyme. Xp katE mutant had resistance levels similar to the parental strain against peroxide and superoxide killing at both exponential and stationary phases of growth. Interestingly, the level of total catalase activity in the mutant was similar to that of the parental strain even in stationary phase. These results suggest the existence of a novel compensatory mechanism for the activity of Xp catalase isozymes.
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Affiliation(s)
- P Vattanaviboon
- Laboratory of Biotechnology, Chulabhorn Research Institute, Lak Si, Bangkok, Thailand
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40
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Zámocký M, Koller F. Understanding the structure and function of catalases: clues from molecular evolution and in vitro mutagenesis. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 1999; 72:19-66. [PMID: 10446501 DOI: 10.1016/s0079-6107(98)00058-3] [Citation(s) in RCA: 213] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
This review gives an overview about the structural organisation of different evolutionary lines of all enzymes capable of efficient dismutation of hydrogen peroxide. Major potential applications in biotechnology and clinical medicine justify further investigations. According to structural and functional similarities catalases can be divided in three subgroups. Typical catalases are homotetrameric haem proteins. The three-dimensional structure of six representatives has been resolved to atomic resolution. The central core of each subunit reveals a characteristic "catalase fold", extremely well conserved among this group. In the native tetramer structure pairs of subunits tightly interact via exchange of their N-terminal arms. This pseudo-knot structures implies a highly ordered assembly pathway. A minor subgroup ("large catalases") possesses an extra flavodoxin-like C-terminal domain. A > or = 25 A long channel leads from the enzyme surface to the deeply buried active site. It enables rapid and selective diffusion of the substrates to the active center. In several catalases NADPH is tightly bound close to the surface. This cofactor may prevent and reverse the formation of compound II, an inactive reaction intermediate. Bifunctional catalase-peroxidase are haem proteins which probably arose via gene duplication of an ancestral peroxidase gene. No detailed structural information is currently available. Even less is know about manganese catalases. Their di-manganese reaction centers may be evolutionary.
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Affiliation(s)
- M Zámocký
- Institut für Biochemie and Molekulare Zellbiologie, Vienna, Austria.
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Vattanaviboon P, Varaluksit T, Mongkolsuk S. Modulation of peroxide stress response by thiol reagents and the role of a redox sensor-transcription regulator, OxyR in mediating the response inXanthomonas. FEMS Microbiol Lett 1999. [DOI: 10.1111/j.1574-6968.1999.tb13699.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Cassarino DS, Bennett JP. An evaluation of the role of mitochondria in neurodegenerative diseases: mitochondrial mutations and oxidative pathology, protective nuclear responses, and cell death in neurodegeneration. BRAIN RESEARCH. BRAIN RESEARCH REVIEWS 1999; 29:1-25. [PMID: 9974149 DOI: 10.1016/s0165-0173(98)00046-0] [Citation(s) in RCA: 292] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
There is mounting evidence for mitochondrial involvement in neurodegenerative diseases including Alzheimer's and Parkinson's disease and amyotrophic lateral sclerosis. Mitochondrial DNA mutations, whether inherited or acquired, lead to impaired electron transport chain (ETC) functioning. Impaired electron transport, in turn, leads to decreased ATP production, formation of damaging free-radicals, and altered calcium handling. These toxic consequences of ETC dysfunction lead to further mitochondrial damage including oxidation of mitochondrial DNA, proteins, and lipids, and opening of the mitochondrial permeability transition pore, an event linked to cell death in numerous model systems. Although protective nuclear responses such as antioxidant enzymes and bcl-2 may be induced to combat these pathological changes, such a vicious cycle of increasing oxidative damage may insidiously damage neurons over a period of years, eventually leading to neuronal cell death. This hypothesis, a synthesis of the mitochondrial mutations and oxidative stress hypotheses of neurodegeneration, is readily tested experimentally, and clearly points out many potential therapeutic targets for preventing or ameliorating these diseases.
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Affiliation(s)
- D S Cassarino
- Medical Scientist Training Program, University of Virginia Health Sciences Center, Charlottesville 22908, USA
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Mongkolsuk S, Rabibhadana S, Sukchavalit R, Vaughn G. Construction and physiological analysis of a Xanthomonas oryzae pv. oryzae recA mutant. FEMS Microbiol Lett 1998; 169:269-75. [PMID: 9868770 DOI: 10.1111/j.1574-6968.1998.tb13328.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
A Xoo recA insertion inactivation mutant was constructed. The mutant, lacking RecA, showed increased sensitivity towards mutagen killing. This phenotype could be complemented by a cloned, functional recA. Unlike other bacteria, both the recA mutant and the parental strain had similar level of resistance to H2O2 killing and peroxide-induced mutagenesis.
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Affiliation(s)
- S Mongkolsuk
- Laboratory of Biotechnology, Chulabhorn Research Institute, Bangkok, Thailand.
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Vattanaviboon P, Mongkolsuk S. Evaluation of the role hydroxyl radicals and iron play in hydrogen peroxide killing ofXanthomonas campestrispv.phaseoli. FEMS Microbiol Lett 1998. [DOI: 10.1111/j.1574-6968.1998.tb13326.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Mongkolsuk S, Sukchawalit R, Loprasert S, Praituan W, Upaichit A. Construction and physiological analysis of a Xanthomonas mutant to examine the role of the oxyR gene in oxidant-induced protection against peroxide killing. J Bacteriol 1998; 180:3988-91. [PMID: 9683499 PMCID: PMC107386 DOI: 10.1128/jb.180.15.3988-3991.1998] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/1998] [Accepted: 05/26/1998] [Indexed: 02/08/2023] Open
Abstract
We constructed and characterized a Xanthomonas campestris pv. phaseoli oxyR mutant. The mutant was hypersensitive to H2O2 and menadione killing and had reduced aerobic plating efficiency. The oxidants' induction of the catalase and ahpC genes was also abolished in the mutant. Analysis of the adaptive responses showed that hydrogen peroxide-induced protection against hydrogen peroxide was lost, while menadione-induced protection against hydrogen peroxide was retained in the oxyR mutant. These results show that X. campestris pv. phaseoli oxyR is essential to peroxide adaptation and revealed the existence of a novel superoxide-inducible peroxide protection system that is independent of OxyR.
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Affiliation(s)
- S Mongkolsuk
- Laboratory of Biotechnology, Chulabhorn Research Institute, Lak Si, Bangkok 10210, Thailand
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Mongkolsuk S, Praituan W, Loprasert S, Fuangthong M, Chamnongpol S. Identification and characterization of a new organic hydroperoxide resistance (ohr) gene with a novel pattern of oxidative stress regulation from Xanthomonas campestris pv. phaseoli. J Bacteriol 1998; 180:2636-43. [PMID: 9573147 PMCID: PMC107214 DOI: 10.1128/jb.180.10.2636-2643.1998] [Citation(s) in RCA: 160] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
We have isolated a new organic hydroperoxide resistance (ohr) gene from Xanthomonas campestris pv. phaseoli. This was done by complementation of an Escherichia coli alkyl hydroperoxide reductase mutant with an organic hydroperoxide-hypersensitive phenotype. ohr encodes a 14.5-kDa protein. Its amino acid sequence shows high homology with several proteins of unknown function. An ohr mutant was subsequently constructed, and it showed increased sensitivity to both growth-inhibitory and killing concentrations of organic hydroperoxides but not to either H2O2 or superoxide generators. No alterations in sensitivity to other oxidants or stresses were observed in the mutant. ohr had interesting expression patterns in response to low concentrations of oxidants. It was highly induced by organic hydroperoxides, weakly induced by H2O2, and not induced at all by a superoxide generator. The novel regulation pattern of ohr suggests the existence of a second organic hydroperoxide-inducible system that differs from the global peroxide regulator system, OxyR. Expression of ohr in various bacteria tested conferred increased resistance to tert-butyl hydroperoxide killing, but this was not so for wild-type Xanthomonas strains. The organic hydroperoxide hypersensitivity of ohr mutants could be fully complemented by expression of ohr or a combination of ahpC and ahpF and could be partially complemented by expression ahpC alone. The data suggested that Ohr was a new type of organic hydroperoxide detoxification protein.
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Affiliation(s)
- S Mongkolsuk
- Laboratory of Biotechnology, Chulabhorn Research Institute, Lak Si, Bangkok 10210, Thailand.
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Mongkolsuk S, Loprasert S, Whangsuk W, Fuangthong M, Atichartpongkun S. Characterization of transcription organization and analysis of unique expression patterns of an alkyl hydroperoxide reductase C gene (ahpC) and the peroxide regulator operon ahpF-oxyR-orfX from Xanthomonas campestris pv. phaseoli. J Bacteriol 1997; 179:3950-5. [PMID: 9190811 PMCID: PMC179204 DOI: 10.1128/jb.179.12.3950-3955.1997] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
We have analyzed the transcription organization of ahpC, ahpF, oxyR, and orfX from Xanthomonas campestris pv. phaseoli. ahpC was transcribed as a monocistronic 0.6-kb mRNA, while ahpF-oxyR-orfX were transcribed as a polycistronic approximately 3.0-kb-long mRNA. The novel transcription organization of these genes has not observed in other bacteria. Western analysis showed that oxidants (peroxides and superoxide anions), a thiol reagent (N-ethylmaleimide), and CdCl2 caused large increases in the steady-state level of AhpC. Growth at alkaline pH also moderately induced AhpC accumulation. Thermal and osmotic stresses did not alter the levels of AhpC. Northern blotting results confirmed that oxidant- and CdCl2-induced AhpC accumulation was due to increased levels of ahpC transcripts. Analysis of oxyR expression revealed a unique pattern. Unlike other bacterial systems, peroxides and a superoxide generator induced accumulation of OxyR. Northern blotting results confirmed that these oxidants induced expression of oxyR operon. This novel regulatory pattern could be generally important. The transcription organization and patterns of chemicals and stress induction of ahpC and oxyR differed from those of other bacteria and are likely to be important for X. campestris pv. phaseoli survival during exposure to oxidants.
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Affiliation(s)
- S Mongkolsuk
- Laboratory of Biotechnology, Chulabhorn Research Institute, Bangkok, Thailand.
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