51
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Song C, Liu B, Xu P, Xie J, Ge X, Zhou Q, Sun C, Zhang H, Shan F, Yang Z. Oxidized fish oil injury stress in Megalobrama amblycephala: Evaluated by growth, intestinal physiology, and transcriptome-based PI3K-Akt/NF-κB/TCR inflammatory signaling. FISH & SHELLFISH IMMUNOLOGY 2018; 81:446-455. [PMID: 30064020 DOI: 10.1016/j.fsi.2018.07.049] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 07/22/2018] [Accepted: 07/27/2018] [Indexed: 06/08/2023]
Abstract
Lipids are essential nutrients for animal. Oxidized lipid might induce injury stress for fish. Here we conducted a 12-week rearing experiment with diets containing 0, 2, 4, and 6% oxidized fish oil (6F, 4F2OF, 2F4OF, and 6OF) to describe the oxidative impairment mechanism on teleost fish blunt snout bream, Megalobrama amblycephala. Results were evaluated by growth performance, intestinal physiology, and transcriptome-based PI3K-Akt/NF-κB/TCR inflammatory signaling. From the results, 6OF reduced growth performance with increased FCR and reduced FBW, WGR and SGR compare with 6 F. Meanwhile, oxidized fish oil treatments also increased antioxidant enzyme activity, suggesting an impaired physiological condition. The plasmatic antioxidant enzyme activity of T-SOD, GSH-Px, ASAFR, concentration of MDA and cortisol were significantly increased in 6OF, while GSH concentration was decreased. Histological ultrastructure revealed the integrity of mid-intestinal cells and villus were destroyed in 6OF. Moreover, transcriptomic analysis revealed PI3K-Akt/NF-κB/TCR inflammatory signaling were active to oxidized fish oil stress. We verified the expression of twelve key genes related to this signaling by RT-PCR, which revealed TLR2, PI3K, Akt, NF-κB, MHCII-β, TCR-α, TGF-β, TNF-α, IL-6, IL-1β, GPx1 and GSTm were all activated under 6OF stimulation. We found that oxidized fish oil may induce oxidative stress, destroy intestinal integrity, produce free radical, dysregulate lipid metabolism and oxidative balance, reversely affect the physiological adaptation, and eventually lead to growth inhibition. This study revealed the mechanism of PI3K-Akt/NF-κB/TCR inflammatory signaling in M. amblycephala under oxidized fish oil stress, which may help to understand the complex regulation involved in lipid oxidative stress resistance.
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Affiliation(s)
- Changyou Song
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, 214081, China; Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, China.
| | - Bo Liu
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, 214081, China; Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, China.
| | - Pao Xu
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, 214081, China; Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, China.
| | - Jun Xie
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, 214081, China; Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, China
| | - Xianping Ge
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, 214081, China; Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, China
| | - Qunlan Zhou
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, China
| | - Cunxin Sun
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, China
| | - Huimin Zhang
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, 214081, China
| | - Fan Shan
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, 214081, China
| | - Zhenfei Yang
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, 214081, China
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52
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Goss CH, Kaneko Y, Khuu L, Anderson GD, Ravishankar S, Aitken ML, Lechtzin N, Zhou G, Czyz DM, McLean K, Olakanmi O, Shuman HA, Teresi M, Wilhelm E, Caldwell E, Salipante SJ, Hornick DB, Siehnel RJ, Becker L, Britigan BE, Singh PK. Gallium disrupts bacterial iron metabolism and has therapeutic effects in mice and humans with lung infections. Sci Transl Med 2018; 10:eaat7520. [PMID: 30257953 PMCID: PMC6637966 DOI: 10.1126/scitranslmed.aat7520] [Citation(s) in RCA: 210] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 09/06/2018] [Indexed: 12/12/2022]
Abstract
The lack of new antibiotics is among the most critical challenges facing medicine. The problem is particularly acute for Gram-negative bacteria. An unconventional antibiotic strategy is to target bacterial nutrition and metabolism. The metal gallium can disrupt bacterial iron metabolism because it substitutes for iron when taken up by bacteria. We investigated the antibiotic activity of gallium ex vivo, in a mouse model of airway infection, and in a phase 1 clinical trial in individuals with cystic fibrosis (CF) and chronic Pseudomonas aeruginosa airway infections. Our results show that micromolar concentrations of gallium inhibited P. aeruginosa growth in sputum samples from patients with CF. Ex vivo experiments indicated that gallium inhibited key iron-dependent bacterial enzymes and increased bacterial sensitivity to oxidants. Furthermore, gallium resistance developed slowly, its activity was synergistic with certain antibiotics, and gallium did not diminish the antibacterial activity of host macrophages. Systemic gallium treatment showed antibiotic activity in murine lung infections. In addition, systemic gallium treatment improved lung function in people with CF and chronic P. aeruginosa lung infection in a preliminary phase 1 clinical trial. These findings raise the possibility that human infections could be treated by targeting iron metabolism or other nutritional vulnerabilities of bacterial pathogens.
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Affiliation(s)
- Christopher H Goss
- Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA
- Department of Pediatrics, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Yukihiro Kaneko
- Department of Bacteriology, Osaka City University School of Medicine, Osaka 545-0051, Japan
| | - Lisa Khuu
- Department of Microbiology, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Gail D Anderson
- Department of Pharmacy, University of Washington School of Pharmacy, Seattle, WA 98195, USA
| | - Sumedha Ravishankar
- Department of Microbiology, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Moira L Aitken
- Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Noah Lechtzin
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Guolin Zhou
- Ben May Department for Cancer Research, University of Chicago, Chicago, IL 60637, USA
| | - Daniel M Czyz
- Department of Microbiology, The University of Chicago, Chicago, IL 60637, USA
| | - Kathryn McLean
- Department of Laboratory Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Oyebode Olakanmi
- University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Howard A Shuman
- Department of Microbiology, The University of Chicago, Chicago, IL 60637, USA
| | - Mary Teresi
- Department of Medicine, University of Nebraska School of Medicine, Omaha, NE 68105, USA
| | - Ellen Wilhelm
- Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Ellen Caldwell
- Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Stephen J Salipante
- Department of Laboratory Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Douglas B Hornick
- Department of Medicine, University of Nebraska School of Medicine, Omaha, NE 68105, USA
| | - Richard J Siehnel
- Department of Microbiology, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Lev Becker
- Ben May Department for Cancer Research, University of Chicago, Chicago, IL 60637, USA
| | - Bradley E Britigan
- Departments of Medicine and Pediatrics, University of Iowa, Iowa City, IA 52242, USA
| | - Pradeep K Singh
- Department of Microbiology, University of Washington School of Medicine, Seattle, WA 98195, USA.
- Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA
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53
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Chingsungnoen A, Maneerat S, Chunpeng P, Poolcharuansin P, Nam-Matra R. Antimicrobial Treatment of Escherichia coli and Staphylococcus aureus in Herbal Tea Using Low-Temperature Plasma. J Food Prot 2018; 81:1503-1507. [PMID: 30109969 DOI: 10.4315/0362-028x.jfp-18-062] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A low-pressure capacitively coupled discharge was used to study antimicrobial treatment in herbal tea. Ambient air with a relative humidity of 40% was used as a precursor gas and fed into the chamber via a perforated power electrode. An electrical discharge plasma was produced at a radio frequency of 10 kHz and power of 80 W. The operating pressure during treatment was kept constant at 260 Pa. The target microorganisms, Escherichia coli and Staphylococcus aureus, isolated from the herbal tea were inoculated on nutrient agar petri dishes and exposed to the plasma for 0.5, 1.0, 1.5, and 2.0 min. All treatments were carried out in triplicate for different exposure times to calculate the D-value by the enumeration method. D-values of 0.73 and 0.67 min were obtained corresponding to E. coli and S. aureus reduction, respectively.
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Affiliation(s)
- Artit Chingsungnoen
- 1 Technological Plasma Research Unit, Department of Physics, Faculty of Science
| | | | - Poramate Chunpeng
- 1 Technological Plasma Research Unit, Department of Physics, Faculty of Science
| | | | - Rachanee Nam-Matra
- 3 Walai Rukhavej Botanical Research Institute, Mahasarakham University, Maha Sarakham 44150, Thailand (ORCID: http://orcid.org/0000-0003-3194-9254 [A.C.])
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54
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Teng T, Xi B, Chen K, Pan L, Xie J, Xu P. Comparative transcriptomic and proteomic analyses reveal upregulated expression of virulence and iron transport factors of Aeromonas hydrophila under iron limitation. BMC Microbiol 2018; 18:52. [PMID: 29866030 PMCID: PMC5987420 DOI: 10.1186/s12866-018-1178-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 04/05/2018] [Indexed: 12/26/2022] Open
Abstract
Background Iron plays important roles in the growth, reproduction and pathogenicity of Aeromonas hydrophila. In this study, we detected and compared the mRNA and protein expression profiles of A. hydrophila under normal and iron restricted medium with 200 μM 2,2-Dipyridyl using RNA Sequencing (RNA-seq) and isobaric tags for relative and absolute quantification (iTRAQ) analyses. Results There were 1204 genes (601 up- and 603 down-regulated) and 236 proteins (90 up- and 146 down-regulated) shown to be differentially expressed, and 167 genes and proteins that showed consistent expression. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses revealed that the differentially expressed genes and proteins were mainly involved in iron ion transport, protein activity, energy metabolism and virulence processes. Further validation of the RNA-seq and iTRAQ results by quantitative real-time PCR (qPCR) revealed that 18 of the 20 selected genes were consistently expressed. The iron-ion absorption and concentration of A. hydrophila under iron-limited conditions were enhanced, and most virulence factors (protease activity, hemolytic activity, lipase activity, and swimming ability) were also increased. Artificial A. hydrophila infection caused higher mortality in cyprinid Megalobrama amblycephala under iron-limited conditions. Conclusion Understanding the responses of pathogenic Aeromonas hydrophila within the hostile environment of the fish host, devoid of free iron, is important to reveal bacterial infection and pathogenesis. This study further confirmed the previous finding that iron-limitation efficiently enhanced the virulence of A. hydrophila using multi-omics analyses. We identified differentially expressed genes and proteins, related to enterobactin synthesis and virulence establishment, that play important roles in addressing iron scarcity. Electronic supplementary material The online version of this article (10.1186/s12866-018-1178-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Tao Teng
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, 214081, China.,Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, China
| | - Bingwen Xi
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, 214081, China.,Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, China
| | - Kai Chen
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, China
| | - Liangkun Pan
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, China
| | - Jun Xie
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, 214081, China. .,Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, China.
| | - Pao Xu
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, 214081, China. .,Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, China.
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55
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Cieplik F, Deng D, Crielaard W, Buchalla W, Hellwig E, Al-Ahmad A, Maisch T. Antimicrobial photodynamic therapy - what we know and what we don't. Crit Rev Microbiol 2018; 44:571-589. [PMID: 29749263 DOI: 10.1080/1040841x.2018.1467876] [Citation(s) in RCA: 514] [Impact Index Per Article: 73.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Considering increasing number of pathogens resistant towards commonly used antibiotics as well as antiseptics, there is a pressing need for antimicrobial approaches that are capable of inactivating pathogens efficiently without the risk of inducing resistances. In this regard, an alternative approach is the antimicrobial photodynamic therapy (aPDT). The antimicrobial effect of aPDT is based on the principle that visible light activates a per se non-toxic molecule, the so-called photosensitizer (PS), resulting in generation of reactive oxygen species that kill bacteria unselectively via an oxidative burst. During the last 10-20 years, there has been extensive in vitro research on novel PS as well as light sources, which is now to be translated into clinics. In this review, we aim to provide an overview about the history of aPDT, its fundamental photochemical and photophysical mechanisms as well as photosensitizers and light sources that are currently applied for aPDT in vitro. Furthermore, the potential of resistances towards aPDT is extensively discussed and implications for proper comparison of in vitro studies regarding aPDT as well as for potential application fields in clinical practice are given. Overall, this review shall provide an outlook on future research directions needed for successful translation of promising in vitro results in aPDT towards clinical practice.
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Affiliation(s)
- Fabian Cieplik
- a Department of Conservative Dentistry and Periodontology , University Medical Center Regensburg , Regensburg , Germany.,b Department of Preventive Dentistry , Academic Center for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam , Amsterdam , The Netherlands
| | - Dongmei Deng
- b Department of Preventive Dentistry , Academic Center for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam , Amsterdam , The Netherlands
| | - Wim Crielaard
- b Department of Preventive Dentistry , Academic Center for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam , Amsterdam , The Netherlands
| | - Wolfgang Buchalla
- a Department of Conservative Dentistry and Periodontology , University Medical Center Regensburg , Regensburg , Germany
| | - Elmar Hellwig
- c Department of Operative Dentistry and Periodontology, Faculty of Medicine , Center for Dental Medicine, University of Freiburg , Freiburg , Germany
| | - Ali Al-Ahmad
- c Department of Operative Dentistry and Periodontology, Faculty of Medicine , Center for Dental Medicine, University of Freiburg , Freiburg , Germany
| | - Tim Maisch
- d Department of Dermatology , University Medical Center Regensburg , Regensburg , Germany
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56
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Lin TH, Tseng CY, Lai YC, Wu CC, Huang CF, Lin CT. IscR Regulation of Type 3 Fimbriae Expression in Klebsiella pneumoniae CG43. Front Microbiol 2017; 8:1984. [PMID: 29085346 PMCID: PMC5650617 DOI: 10.3389/fmicb.2017.01984] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 09/26/2017] [Indexed: 01/25/2023] Open
Abstract
In Klebsiella pneumoniae, we have previously shown that IscR, an Fe–S cluster-containing transcriptional factor, plays a dual role in controlling capsular polysaccharide biosynthesis and iron-acquisition systems by switching between its holo and apo forms. In this study, the effect of IscR on type 3 fimbriae expression and biofilm formation was investigated. We found that production of the major subunit of type 3 fimbriae, MrkA, was increased in the ΔiscR and iscR3CA strains, a strain expressing a mutant IscR that mimics apo-IscR, at both the translational and transcriptional levels. Based on the fact that type 3 fimbriae expression is the major factor affecting biofilm formation, increased biofilm formation was also found in ΔiscR or iscR3CA, suggesting that holo-IscR represses biofilm formation. However, the repression of type 3 fimbriae expression by IscR is indirect. To further understand the regulatory mechanism of IscR, the effect of IscR on the expression of mrkHIJ, which encodes cyclic di-GMP (c-di-GMP)-related regulatory proteins that control type 3 fimbriae expression, was studied. We found that holo-IscR could directly repress mrkHI transcription, indicating that MrkHI is required for IscR regulation of type 3 fimbriae expression. Finally, deletion of iscR attenuated K. pneumoniae virulence in a peritonitis model of mouse infection, while the absence of the [2Fe–2S] cluster of IscR had no effect on K. pneumoniae virulence during infection. Taken together, our results demonstrate the underlying mechanism of the [2Fe–2S] cluster of IscR in controlling type 3 fimbriae expression and its effect on K. pneumoniae pathogenesis.
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Affiliation(s)
- Tien-Huang Lin
- Division of Urology, Taichung Tzu Chi General Hospital, The Buddhist Tzu Chi Medical Foundation, Taichung, Taiwan.,School of Post-Baccalaureate Chinese Medicine, Tzu Chi University, Hualien, Taiwan
| | - Cheng-Yin Tseng
- Graduate Institute of Chinese Medicine, China Medical University, Taichung, Taiwan.,Section of Infectious Disease, Hsinchu Mackay Memorial Hospital, Hsinchu, Taiwan
| | - Yi-Chyi Lai
- Department of Microbiology and Immunology, Chung-Shan Medical University, Taichung, Taiwan
| | - Chien-Chen Wu
- School of Chinese Medicine, China Medical University, Taichung, Taiwan
| | - Chun-Fa Huang
- Graduate Institute of Chinese Medicine, China Medical University, Taichung, Taiwan.,School of Chinese Medicine, China Medical University, Taichung, Taiwan
| | - Ching-Ting Lin
- Graduate Institute of Chinese Medicine, China Medical University, Taichung, Taiwan.,School of Chinese Medicine, China Medical University, Taichung, Taiwan
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57
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Browne HP, Neville BA, Forster SC, Lawley TD. Transmission of the gut microbiota: spreading of health. Nat Rev Microbiol 2017; 15:531-543. [PMID: 28603278 PMCID: PMC5837012 DOI: 10.1038/nrmicro.2017.50] [Citation(s) in RCA: 148] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Transmission of commensal intestinal bacteria between humans could promote health by establishing, maintaining and replenishing microbial diversity in the microbiota of an individual. Unlike pathogens, the routes of transmission for commensal bacteria remain unappreciated and poorly understood, despite the likely commonalities between both. Consequently, broad infection control measures that are designed to prevent pathogen transmission and infection, such as oversanitation and the overuse of antibiotics, may inadvertently affect human health by altering normal commensal transmission. In this Review, we discuss the mechanisms and factors that influence host-to-host transmission of the intestinal microbiota and examine how a better understanding of these processes will identify new approaches to nurture and restore transmission routes that are used by beneficial bacteria.
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Affiliation(s)
- Hilary P Browne
- Host-Microbiota Interactions Laboratory, Wellcome Trust Sanger Institute, Hinxton, Cambridgeshire CB10 1SA, UK
| | - B Anne Neville
- Host-Microbiota Interactions Laboratory, Wellcome Trust Sanger Institute, Hinxton, Cambridgeshire CB10 1SA, UK
| | - Samuel C Forster
- Host-Microbiota Interactions Laboratory, Wellcome Trust Sanger Institute, Hinxton, Cambridgeshire CB10 1SA, UK
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, Victoria 3168, Australia
- Department of Molecular and Translational Sciences, Monash University, Clayton, Victoria 3800, Australia
| | - Trevor D Lawley
- Host-Microbiota Interactions Laboratory, Wellcome Trust Sanger Institute, Hinxton, Cambridgeshire CB10 1SA, UK
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58
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Tan ND, Yuan Y, Yin JH, Xu N. Quenching of Salicylaldehyde-based Luminescence ProbeviaDakin Reaction: Approach for Highly Selective Detection of Hydrogen Peroxide. B KOREAN CHEM SOC 2017. [DOI: 10.1002/bkcs.11190] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Nai-Di Tan
- College of Chemistry and Pharmaceutical Engineering; Jilin Institute of Chemical Technology; Jilin 132022 China
| | - Yaqing Yuan
- College of Materials Science and Engineering; Jilin Institute of Chemical Technology; Jilin 132022 China
| | - Jian-Hang Yin
- College of Materials Science and Engineering; Jilin Institute of Chemical Technology; Jilin 132022 China
| | - Na Xu
- College of Materials Science and Engineering; Jilin Institute of Chemical Technology; Jilin 132022 China
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59
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Yan S, Wu G. Reorganization of gene network for degradation of polycyclic aromatic hydrocarbons (PAHs) in Pseudomonas aeruginosa PAO1 under several conditions. J Appl Genet 2017; 58:545-563. [PMID: 28685384 PMCID: PMC5655620 DOI: 10.1007/s13353-017-0402-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 05/22/2017] [Accepted: 06/06/2017] [Indexed: 01/05/2023]
Abstract
Although polycyclic aromatic hydrocarbons (PAHs) are harmful to human health, their elimination from the environment is not easy. Biodegradation of PAHs is promising since many bacteria have the ability to use hydrocarbons as their sole carbon and energy sources for growth. Of various microorganisms that can degrade PAHs, Pseudomonas aeruginosa is particularly important, not only because it causes a series of diseases including infection in cystic fibrosis patients, but also because it is a model bacterium in various studies. The genes that are responsible for degrading PAHs have been identified in P. aeruginosa, however, no gene acts alone as various stresses often initiate different metabolic pathways, quorum sensing, biofilm formation, antibiotic tolerance, etc. Therefore, it is important to study how PAH degradation genes behave under different conditions. In this study, we apply network analysis to investigating how 46 PAH degradation genes reorganized among 5549 genes in P. aeruginosa PAO1 under nine different conditions using publicly available gene coexpression data from GEO. The results provide six aspects of novelties: (i) comparing the number of gene clusters before and after stresses, (ii) comparing the membership in each gene cluster before and after stresses, (iii) defining which gene changed its membership together with PAH degradation genes before and after stresses, (iv) classifying membership-changed-genes in terms of category in Pseudomonas Genome Database, (v) postulating unknown gene’s function, and (vi) proposing new mechanisms for genes of interests. This study can shed light on understanding of cooperative mechanisms of PAH degradation from the level of entire genes in an organism, and paves the way to conduct the similar studies on other genes.
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Affiliation(s)
- Shaomin Yan
- Bioscience and Technology Research Center, Guangxi Academy of Sciences, 98 Daling Road, Nanning, Guangxi, 530007, China
| | - Guang Wu
- Bioscience and Technology Research Center, Guangxi Academy of Sciences, 98 Daling Road, Nanning, Guangxi, 530007, China.
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60
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Daiber A, Di Lisa F, Oelze M, Kröller‐Schön S, Steven S, Schulz E, Münzel T. Crosstalk of mitochondria with NADPH oxidase via reactive oxygen and nitrogen species signalling and its role for vascular function. Br J Pharmacol 2017; 174:1670-1689. [PMID: 26660451 PMCID: PMC5446573 DOI: 10.1111/bph.13403] [Citation(s) in RCA: 183] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Revised: 09/22/2015] [Accepted: 11/30/2015] [Indexed: 12/21/2022] Open
Abstract
Cardiovascular diseases are associated with and/or caused by oxidative stress. This concept has been proven by using the approach of genetic deletion of reactive species producing (pro-oxidant) enzymes as well as by the overexpression of reactive species detoxifying (antioxidant) enzymes leading to a marked reduction of reactive oxygen and nitrogen species (RONS) and in parallel to an amelioration of the severity of diseases. Likewise, the development and progression of cardiovascular diseases is aggravated by overexpression of RONS producing enzymes as well as deletion of antioxidant RONS detoxifying enzymes. Thus, the consequences of the interaction (redox crosstalk) of superoxide/hydrogen peroxide produced by mitochondria with other ROS producing enzymes such as NADPH oxidases (Nox) are of outstanding importance and will be discussed including the consequences for endothelial nitric oxide synthase (eNOS) uncoupling as well as the redox regulation of the vascular function/tone in general (soluble guanylyl cyclase, endothelin-1, prostanoid synthesis). Pathways and potential mechanisms leading to this crosstalk will be analysed in detail and highlighted by selected examples from the current literature including hypoxia, angiotensin II-induced hypertension, nitrate tolerance, aging and others. The general concept of redox-based activation of RONS sources via "kindling radicals" and enzyme-specific "redox switches" will be discussed providing evidence that mitochondria represent key players and amplifiers of the burden of oxidative stress. LINKED ARTICLES This article is part of a themed section on Redox Biology and Oxidative Stress in Health and Disease. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.12/issuetoc.
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Affiliation(s)
- Andreas Daiber
- Center for Cardiology, Laboratory of Molecular CardiologyMedical Center of the Johannes Gutenberg UniversityMainzGermany
| | - Fabio Di Lisa
- Department of Biomedical SciencesUniversity of PadovaPadovaItaly
| | - Matthias Oelze
- Center for Cardiology, Laboratory of Molecular CardiologyMedical Center of the Johannes Gutenberg UniversityMainzGermany
| | - Swenja Kröller‐Schön
- Center for Cardiology, Laboratory of Molecular CardiologyMedical Center of the Johannes Gutenberg UniversityMainzGermany
| | - Sebastian Steven
- Center for Cardiology, Laboratory of Molecular CardiologyMedical Center of the Johannes Gutenberg UniversityMainzGermany
- Center of Thrombosis and HemostasisMedical Center of the Johannes Gutenberg UniversityMainzGermany
| | - Eberhard Schulz
- Center for Cardiology, Laboratory of Molecular CardiologyMedical Center of the Johannes Gutenberg UniversityMainzGermany
| | - Thomas Münzel
- Center for Cardiology, Laboratory of Molecular CardiologyMedical Center of the Johannes Gutenberg UniversityMainzGermany
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61
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Bishayi B, Nandi A, Dey R, Adhikary R. Expression of CXCR1 (IL-8 receptor A) in splenic, peritoneal macrophages and resident bone marrow cells after acute live or heat killed Staphylococcus aureus stimulation in mice. Microb Pathog 2017; 109:131-150. [PMID: 28552636 DOI: 10.1016/j.micpath.2017.05.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 05/15/2017] [Accepted: 05/19/2017] [Indexed: 10/19/2022]
Abstract
Literature reveals that interaction with live Staphylococcus aureus (S. aureus) or heat killed S. aureus (HKSA) promotes secretion of CXCL-8 or interleukin-8 (IL-8) from leukocytes, however, the expressions of CXCR1 in murine splenic (SPM), peritoneal macrophages (PM) and resident fresh bone marrow cells (FBMC) have not been identified. Currently, very few studies are available on the functional characterization of CXCR1 in mouse macrophage subtypes and its modulation in relation to acute S. aureus infection. SPM, PM and FBMCs were infected with viable S. aureus or stimulated with HKSA in presence and absence of anti-CXCR1 antibody in this study. We reported here that CXCR1 was not constitutively expressed by macrophage subtypes and the receptor was induced only after S. aureus stimulation. The CXCR1 band was found specific as we compared with human polymorphonuclear neutrophils (PMNs) as a positive control (data not shown). Although, we did not show that secreted IL-8 from S. aureus-infected macrophages promotes migration of PMNs. Blocking of cell surface CXCR1 decreases the macrophage's ability to clear staphylococcal infection, attenuates proinflammatory cytokine production and the increased catalase and decreased superoxide dismutase (SOD) enzymes of the bacteria might indicate their role in scavenging macrophage derived hydrogen peroxide (H2O2). The decreased levels of cytokines due to CXCR1 blockade before S. aureus infection appear to regulate the killing of bacteria by destroying H2O2 and nitric oxide (NO). Moreover, functional importance of macrophage subpopulation heterogeneity might be important in designing new effective approaches to limit S. aureus infection induced inflammation and cytotoxicity.
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Affiliation(s)
- Biswadev Bishayi
- Department of Physiology, Immunology Laboratory, University of Calcutta, University Colleges of Science and Technology, 92 APC Road, Calcutta 700009, West Bengal, India.
| | - Ajeya Nandi
- Department of Physiology, Immunology Laboratory, University of Calcutta, University Colleges of Science and Technology, 92 APC Road, Calcutta 700009, West Bengal, India
| | - Rajen Dey
- Department of Physiology, Immunology Laboratory, University of Calcutta, University Colleges of Science and Technology, 92 APC Road, Calcutta 700009, West Bengal, India
| | - Rana Adhikary
- Department of Physiology, Immunology Laboratory, University of Calcutta, University Colleges of Science and Technology, 92 APC Road, Calcutta 700009, West Bengal, India
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Schuster M, Sexton DJ, Hense BA. Why Quorum Sensing Controls Private Goods. Front Microbiol 2017; 8:885. [PMID: 28579979 PMCID: PMC5437708 DOI: 10.3389/fmicb.2017.00885] [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: 02/27/2017] [Accepted: 05/02/2017] [Indexed: 12/22/2022] Open
Abstract
Cell-cell communication, also termed quorum sensing (QS), is a widespread process that coordinates gene expression in bacterial populations. The generally accepted view is that QS optimizes the cell density-dependent benefit attained from cooperative behaviors, often in the form of secreted products referred to as "public goods." This view is challenged by an increasing number of cell-associated products or "private goods" reported to be under QS-control for which a collective benefit is not apparent. A prominent example is nucleoside hydrolase from Pseudomonas aeruginosa, a periplasmic enzyme that catabolizes adenosine. Several recent studies have shown that private goods can function to stabilize cooperation by co-regulated public goods, seemingly explaining their control by QS. Here we argue that this property is a by-product of selection for other benefits rather than an adaptation. Emphasizing ecophysiological context, we propose alternative explanations for the QS control of private goods. We suggest that the benefit attained from private goods is associated with high cell density, either because a relevant ecological condition correlates with density, or because the private good is, directly or indirectly, involved in cooperative behavior. Our analysis helps guide a systems approach to QS, with implications for antivirulence drug design and synthetic biology.
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Affiliation(s)
- Martin Schuster
- Department of Microbiology, Oregon State UniversityCorvallis, OR, United States
| | - D Joseph Sexton
- Department of Microbiology, Oregon State UniversityCorvallis, OR, United States
| | - Burkhard A Hense
- Institute of Computational Biology, Helmholtz Zentrum MünchenNeuherberg, Germany
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63
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Minasyan H. Sepsis and septic shock: Pathogenesis and treatment perspectives. J Crit Care 2017; 40:229-242. [PMID: 28448952 DOI: 10.1016/j.jcrc.2017.04.015] [Citation(s) in RCA: 89] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 03/06/2017] [Accepted: 04/08/2017] [Indexed: 12/12/2022]
Abstract
The majority of bacteremias do not develop to sepsis: bacteria are cleared from the bloodstream. Oxygen released from erythrocytes and humoral immunity kill bacteria in the bloodstream. Sepsis develops if bacteria are resistant to oxidation and proliferate in erythrocytes. Bacteria provoke oxygen release from erythrocytes to arterial blood. Abundant release of oxygen to the plasma triggers a cascade of events that cause: 1. oxygen delivery failure to cells; 2. oxidation of plasma components that impairs humoral regulation and inactivates immune complexes; 3. disseminated intravascular coagulation and multiple organs' failure. Bacterial reservoir inside erythrocytes provides the long-term survival of bacteria and is the cause of ineffectiveness of antibiotics and host immune reactions. Treatment perspectives that include different aspects of sepsis development are discussed.
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Niepa THR, Wang H, Gilbert JL, Ren D. Eradication of Pseudomonas aeruginosa cells by cathodic electrochemical currents delivered with graphite electrodes. Acta Biomater 2017; 50:344-352. [PMID: 28049020 DOI: 10.1016/j.actbio.2016.12.053] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 11/29/2016] [Accepted: 12/30/2016] [Indexed: 11/30/2022]
Abstract
Antibiotic resistance is a major challenge to the treatment of bacterial infections associated with medical devices and biomaterials. One important intrinsic mechanism of such resistance is the formation of persister cells that are phenotypic variants of microorganisms and highly tolerant to antibiotics. Recently, we reported a new approach to eradicating persister cells of Pseudomonas aeruginosa using low-level direct electrochemical current (DC) and synergy with the antibiotic tobramycin. To further understand the underlying mechanism and develop this technology toward possible medical applications, we investigated the electricidal activities of non-metallic biomaterial on persister and biofilm cells of P. aeruginosa using graphite-based TGON™ 805 electrodes. We employed both single and dual chamber systems to compare electrochemical factors of TGON and stainless steel 304 electrodes. The results revealed that TGON-based treatments were highly effective against P. aeruginosa persister cells. In the single chamber system, complete eradication of planktonic persister cells (corresponding to a 7-log killing) was achieved with 70μA/cm2 DC using TGON electrodes within 40min of treatment, while the cell viability in biofilms was reduced by 2 logs within 1h. The killing effects were dose and time dependent with higher current densities requiring less time. Moreover, reduction reactions were found more effective than oxidation reactions, confirming that metal cations are not indispensable, although they may facilitate cell killing. The findings of this study can help develop electrochemical technologies to eradicate persister and biofilm cells for more effective treatment of medical device and biomaterial associated infections. STATEMENT OF SIGNIFICANCE Infections associated with medical devices and biomaterials present a major challenge due to high-level tolerance of microbes to conventional antibiotics. It is well established that such tolerance is due to the formation of dormant persister cells and multicellular structures known as biofilms. Recent studies have demonstrated electrochemical treatment as a promising alternative to eradicate bacterial infections, since the killing mechanism is independent of the growth phase of bacterial cells, but relies on various electrochemical species interplaying during the treatment. The current study investigated major bactericidal properties of the electrochemical currents mediated via TGON, a carbon-based electrode material. Up to total eradication of Pseudomonas aeruginosa persister cells was achieved. The new knowledge of electrochemical properties and the bioactivity of TGON may help develop new methods/devices to eradicate bacterial infections by delivering safe levels of electrochemical currents.
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Affiliation(s)
- Tagbo H R Niepa
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY 13244, USA; Syracuse Biomaterials Institute, Syracuse University, Syracuse, NY 13244, USA
| | - Hao Wang
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY 13244, USA; Syracuse Biomaterials Institute, Syracuse University, Syracuse, NY 13244, USA
| | - Jeremy L Gilbert
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY 13244, USA; Syracuse Biomaterials Institute, Syracuse University, Syracuse, NY 13244, USA
| | - Dacheng Ren
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY 13244, USA; Syracuse Biomaterials Institute, Syracuse University, Syracuse, NY 13244, USA; Department of Civil and Environmental Engineering, Syracuse University, Syracuse, NY 13244, USA; Department of Biology, Syracuse University, Syracuse, NY 13244, USA.
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Activity of Electrical Current in Experimental Propionibacterium acnes Foreign-Body Osteomyelitis. Antimicrob Agents Chemother 2017; 61:AAC.01863-16. [PMID: 27821457 DOI: 10.1128/aac.01863-16] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 10/11/2016] [Indexed: 12/14/2022] Open
Abstract
Foreign-body-associated infections are often difficult to treat, given that the associated microorganisms are in a biofilm state. Previously, we showed that a low-amperage direct electrical current (DC) reduces Propionibacterium acnes biofilms formed on implant-associated materials in vitro In this study, low-amperage DC was compared to ceftriaxone treatment or no treatment in a novel rat femur model of foreign-body osteomyelitis. A platinum implant seeded with a P. acnes biofilm (107 CFU/cm2) and 109 CFU of planktonic P. acnes was placed in the femoral medullary cavity. One week later, rats were assigned to one of three treatment groups: no treatment, ceftriaxone treatment, or 200-μA-DC treatment. After 2 weeks of treatment, there were fewer bacteria in the bones of the ceftriaxone group (3.06 log10 CFU/g of bone [P = 0.0209]) and the 200-μA-DC group (0.5 log10 CFU/g [P = 0.0015]) than in those of the control group (6.58 log10 CFU/g). The DC-exposed animals exhibited fewer bacteria than the ceftriaxone-treated animals (P = 0.0330). There were fewer bacteria on the implanted wires in the groups treated with ceftriaxone (0.1 log10 CFU/cm2) or a 200-μA DC (0.1 log10 CFU/cm2) than in the control group (2.53 log10 CFU/cm2 [P, 0.0003 for both comparisons]). Low-amperage DC may be useful for treating, or aiding in the treatment of, foreign-body infections caused by P. acnes.
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Xin Q, Liu Q, Shah H, Gong JR. Electron spin resonance and fluorescence imaging assisted electrochemical approach for accurate and comprehensive monitoring of cellular hydrogen peroxide dynamics. Analyst 2017; 142:316-325. [DOI: 10.1039/c6an02006b] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new analytical system combining electrochemistry, ESR, and fluorescence imaging for accurately and comprehensively measuring the dynamics of cellular H2O2.
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Affiliation(s)
- Qi Xin
- CAS Center for Excellence in Nanoscience
- CAS Key Laboratory for Nanosystem and Hierarchical Fabrication
- National Center for Nanoscience and Technology
- Beijing 100190
- P. R. China
| | - Qian Liu
- CAS Center for Excellence in Nanoscience
- CAS Key Laboratory for Nanosystem and Hierarchical Fabrication
- National Center for Nanoscience and Technology
- Beijing 100190
- P. R. China
| | - Hameed Shah
- CAS Center for Excellence in Nanoscience
- CAS Key Laboratory for Nanosystem and Hierarchical Fabrication
- National Center for Nanoscience and Technology
- Beijing 100190
- P. R. China
| | - Jian Ru Gong
- CAS Center for Excellence in Nanoscience
- CAS Key Laboratory for Nanosystem and Hierarchical Fabrication
- National Center for Nanoscience and Technology
- Beijing 100190
- P. R. China
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Lee A, Kinney P, Chillrud S, Jack D. A Systematic Review of Innate Immunomodulatory Effects of Household Air Pollution Secondary to the Burning of Biomass Fuels. Ann Glob Health 2016; 81:368-74. [PMID: 26615071 PMCID: PMC4758189 DOI: 10.1016/j.aogh.2015.08.006] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Household air pollution (HAP)-associated acute lower respiratory infections cause 455,000 deaths and a loss of 39.1 million disability-adjusted life years annually. The immunomodulatory mechanisms of HAP are poorly understood. OBJECTIVES The aim of this study was to conduct a systematic review of all studies examining the mechanisms underlying the relationship between HAP secondary to solid fuel exposure and acute lower respiratory tract infection to evaluate current available evidence, identify gaps in knowledge, and propose future research priorities. METHODS We conducted and report on studies in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. In all, 133 articles were fully reviewed and main characteristics were detailed, namely study design and outcome, including in vivo versus in vitro and pollutants analyzed. Thirty-six studies were included in a nonexhaustive review of the innate immune system effects of ambient air pollution, traffic-related air pollution, or wood smoke exposure of developed country origin. Seventeen studies investigated the effects of HAP-associated solid fuel (biomass or coal smoke) exposure on airway inflammation and innate immune system function. RESULTS Particulate matter may modulate the innate immune system and increase susceptibility to infection through a) alveolar macrophage-driven inflammation, recruitment of neutrophils, and disruption of barrier defenses; b) alterations in alveolar macrophage phagocytosis and intracellular killing; and c) increased susceptibility to infection via upregulation of receptors involved in pathogen invasion. CONCLUSIONS HAP secondary to the burning of biomass fuels alters innate immunity, predisposing children to acute lower respiratory tract infections. Data from biomass exposure in developing countries are scarce. Further study is needed to define the inflammatory response, alterations in phagocytic function, and upregulation of receptors important in bacterial and viral binding. These studies have important public health implications and may lead to the design of interventions to improve the health of billions of people daily.
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Affiliation(s)
- Alison Lee
- Division of Pulmonary, Critical Care and Sleep Medicine, Icahn School of Medicine at Mount Sinai, New York, NY.
| | - Patrick Kinney
- Mailman School of Public Health, Department of Environmental Health Sciences, Columbia University, New York, NY
| | - Steve Chillrud
- Lamont-Doherty Earth Observatory, Columbia University, New York, NY
| | - Darby Jack
- Mailman School of Public Health, Department of Environmental Health Sciences, Columbia University, New York, NY
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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: 2.7] [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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Wittwer M, Luo Q, Kaila VRI, Dames SA. Oxidative Unfolding of the Rubredoxin Domain and the Natively Disordered N-terminal Region Regulate the Catalytic Activity of Mycobacterium tuberculosis Protein Kinase G. J Biol Chem 2016; 291:27062-27072. [PMID: 27810897 DOI: 10.1074/jbc.m116.747089] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 10/19/2016] [Indexed: 11/06/2022] Open
Abstract
Mycobacterium tuberculosis escapes killing in human macrophages by secreting protein kinase G (PknG). PknG intercepts host signaling to prevent fusion of the phagosome engulfing the mycobacteria with the lysosome and, thus, their degradation. The N-terminal NORS (no regulatory secondary structure) region of PknG (approximately residues 1-75) has been shown to play a role in PknG regulation by (auto)phosphorylation, whereas the following rubredoxin-like metal-binding motif (RD, residues ∼74-147) has been shown to interact tightly with the subsequent catalytic domain (approximately residues 148-420) to mediate its redox regulation. Deletions or mutations in NORS or the redox-sensitive RD significantly decrease PknG survival function. Based on combined NMR spectroscopy, in vitro kinase assay, and molecular dynamics simulation data, we provide novel insights into the regulatory roles of the N-terminal regions. The NORS region is indeed natively disordered and rather dynamic. Consistent with most earlier data, autophosphorylation occurs in our assays only when the NORS region is present and, thus, in the NORS region. Phosphorylation of it results only in local conformational changes and does not induce interactions with the subsequent RD. Although the reduced, metal-bound RD makes tight interactions with the following catalytic domain in the published crystal structures, it can also fold in its absence. Our data further suggest that oxidation-induced unfolding of the RD regulates substrate access to the catalytic domain and, thereby, PknG function under different redox conditions, e.g. when exposed to increased levels of reactive oxidative species in host macrophages.
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Affiliation(s)
| | - Qi Luo
- Computational Biocatalysis, Department of Chemistry, Technische Universität München, Lichtenbergstr. 4, 85747 Garching, Germany.,the Soft Matter Research Center and Department of Chemistry, Zhejiang University, Hangzhou 310027, China, and
| | - Ville R I Kaila
- Computational Biocatalysis, Department of Chemistry, Technische Universität München, Lichtenbergstr. 4, 85747 Garching, Germany
| | - Sonja A Dames
- From the Biomolecular NMR Spectroscopy and .,the Institute of Structural Biology, Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
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Kim S, Lee JH, Seok JH, Park YH, Jung SW, Cho AE, Lee C, Chung MS, Kim KH. Structural Basis of Novel Iron-Uptake Route and Reaction Intermediates in Ferritins from Gram-Negative Bacteria. J Mol Biol 2016; 428:5007-5018. [PMID: 27777002 DOI: 10.1016/j.jmb.2016.10.022] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 10/17/2016] [Accepted: 10/18/2016] [Indexed: 10/20/2022]
Abstract
Iron and oxygen chemistry is mediated by iron proteins for many biological functions. Carboxylate-bridged diiron enzymes including ferritin have the common mechanism of oxygen activation via peroxodiferric intermediates. However, the route for iron uptake and the structural identification of intermediates still remain incomplete. The 4-fold symmetry channel of Helicobacter pylori ferritin was previously proposed as the iron-uptake route in eubacteria, but the amino acid residues at the 4-fold channel are not highly conserved. Here, we show evidence for a short path for iron uptake from His93 on the surface to the ferroxidase center in H. pylori ferritin and Escherichia coli ferritin. The amino acid residues along this path are highly conserved in Gram-negative bacteria and some archaea, and the mutants containing S20A and H93L showed significantly decreased iron oxidation. Surprisingly, the E. coli ferritin S20A crystal structure showed oxygen binding and side-on, symmetric μ-η2:η2 peroxodiferric and oxodiferric intermediates. The results provide the structural basis for understanding the chemical nature of intermediates in iron oxidation in bacteria and some of archaea.
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Affiliation(s)
- Sella Kim
- Department of Biotechnology & Bioinformatics, Korea University, Sejong 339-700, Korea
| | - Ji-Hye Lee
- Department of Biotechnology & Bioinformatics, Korea University, Sejong 339-700, Korea
| | - Jong Hyeon Seok
- Department of Biotechnology & Bioinformatics, Korea University, Sejong 339-700, Korea
| | - Yi-Ho Park
- Department of Biotechnology & Bioinformatics, Korea University, Sejong 339-700, Korea
| | - Sang Won Jung
- Department of Biotechnology & Bioinformatics, Korea University, Sejong 339-700, Korea
| | - Art E Cho
- Department of Biotechnology & Bioinformatics, Korea University, Sejong 339-700, Korea
| | - Cheolju Lee
- Functional Proteomics Center, Korea Institute of Science and Technology, Seoul 136-791, Korea
| | - Mi Sook Chung
- Department of Food and Nutrition, Duksung Women's University, Seoul 132-714, Korea
| | - Kyung Hyun Kim
- Department of Biotechnology & Bioinformatics, Korea University, Sejong 339-700, Korea.
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Sun Y, Wang Y, Tian C. bZIP transcription factor CgAP1 is essential for oxidative stress tolerance and full virulence of the poplar anthracnose fungus Colletotrichum gloeosporioides. Fungal Genet Biol 2016; 95:58-66. [PMID: 27544415 DOI: 10.1016/j.fgb.2016.08.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 08/10/2016] [Accepted: 08/16/2016] [Indexed: 11/28/2022]
Abstract
Yeast AP1 transcription factor is a regulator of oxidative stress response. Here, we report the identification and characterization of CgAP1, an ortholog of YAP1 in poplar anthracnose fungus Colletotrichum gloeosporioides. The expression of CgAP1 was highly induced by reactive oxygen species. CgAP1 deletion mutants displayed enhanced sensitivity to oxidative stress compared with the wild-type strain, and their poplar leaf virulence was obviously reduced. However, the mutants exhibited no obvious defects in aerial hyphal growth, conidia production, and appressoria formation. CgAP1::eGFP fusion protein localized to the nucleus after TBH (tert-Butyl hydroperoxide) treatment, suggesting that CgAP1 functions as a redox sensor in C. gloeosporioides. In addition, CgAP1 prevented the accumulation of ROS during early stages of biotrophic growth. CgAP1 also acted as a positive regulator of several ROS-related genes (i.e., Glr1, Hyr1, and Cyt1) involved in the antioxidative response. These results highlight the key regulatory role of CgAP1 transcription factor in oxidative stress response and provide insights into the function of ROS detoxification in virulence of C. gloeosporioides.
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Affiliation(s)
- Yingjiao Sun
- The Key Laboratory for Silviculture and Conservation of Ministry of Education, College of Forestry, Beijing Forestry University, Beijing, China
| | - Yonglin Wang
- The Key Laboratory for Silviculture and Conservation of Ministry of Education, College of Forestry, Beijing Forestry University, Beijing, China.
| | - Chengming Tian
- The Key Laboratory for Silviculture and Conservation of Ministry of Education, College of Forestry, Beijing Forestry University, Beijing, China
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72
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Cytochrome bd Displays Significant Quinol Peroxidase Activity. Sci Rep 2016; 6:27631. [PMID: 27279363 PMCID: PMC4899803 DOI: 10.1038/srep27631] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 05/23/2016] [Indexed: 12/29/2022] Open
Abstract
Cytochrome bd is a prokaryotic terminal oxidase that catalyses the electrogenic reduction of oxygen to water using ubiquinol as electron donor. Cytochrome bd is a tri-haem integral membrane enzyme carrying a low-spin haem b558, and two high-spin haems: b595 and d. Here we show that besides its oxidase activity, cytochrome bd from Escherichia coli is a genuine quinol peroxidase (QPO) that reduces hydrogen peroxide to water. The highly active and pure enzyme preparation used in this study did not display the catalase activity recently reported for E. coli cytochrome bd. To our knowledge, cytochrome bd is the first membrane-bound quinol peroxidase detected in E. coli. The observation that cytochrome bd is a quinol peroxidase, can provide a biochemical basis for its role in detoxification of hydrogen peroxide and may explain the frequent findings reported in the literature that indicate increased sensitivity to hydrogen peroxide and decreased virulence in mutants that lack the enzyme.
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Bang YJ, Lee ZW, Kim D, Jo I, Ha NC, Choi SH. OxyR2 Functions as a Three-state Redox Switch to Tightly Regulate Production of Prx2, a Peroxiredoxin of Vibrio vulnificus. J Biol Chem 2016; 291:16038-47. [PMID: 27268058 DOI: 10.1074/jbc.m115.710343] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2015] [Indexed: 11/06/2022] Open
Abstract
The bacterial transcriptional regulator OxyR is known to function as a two-state redox switch. OxyR senses cellular levels of H2O2 via a "sensing cysteine" that switches from the reduced to a disulfide state upon H2O2 exposure, inducing the expression of antioxidant genes. The reduced and disulfide states of OxyR, respectively, bind to extended and compact regions of DNA, where the reduced state blocks and the oxidized state allows transcription and further induces target gene expression by interacting with RNA polymerase. Vibrio vulnificus OxyR2 senses H2O2 with high sensitivity and induces the gene encoding the antioxidant Prx2. In this study, we used mass spectrometry to identify a third redox state of OxyR2, in which the sensing cysteine was overoxidized to S-sulfonated cysteine (Cys-SO3H) by high H2O2 in vitro and in vivo, where the modification deterred the transcription of prx2 The DNA binding preferences of OxyR25CA-C206D, which mimics overoxidized OxyR2, suggested that overoxidized OxyR2 binds to the extended DNA site, masking the -35 region of the prx2 promoter. These combined results demonstrate that OxyR2 functions as a three-state redox switch to tightly regulate the expression of prx2, preventing futile production of Prx2 in cells exposed to high levels of H2O2 sufficient to inactivate Prx2. We further provide evidence that another OxyR homolog, OxyR1, displays similar three-state behavior, inviting further exploration of this phenomenon as a potentially general regulatory mechanism.
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Affiliation(s)
- Ye-Ji Bang
- From the National Research Laboratory of Molecular Microbiology and Toxicology and the Department of Agricultural Biotechnology, and Center for Food Safety and Toxicology, Seoul National University, Seoul 08826, Korea
| | - Zee-Won Lee
- From the National Research Laboratory of Molecular Microbiology and Toxicology and the Department of Agricultural Biotechnology, and Center for Food Safety and Toxicology, Seoul National University, Seoul 08826, Korea
| | - Dukyun Kim
- From the National Research Laboratory of Molecular Microbiology and Toxicology and the Department of Agricultural Biotechnology, and Center for Food Safety and Toxicology, Seoul National University, Seoul 08826, Korea
| | - Inseong Jo
- the Department of Agricultural Biotechnology, and Center for Food Safety and Toxicology, Seoul National University, Seoul 08826, Korea
| | - Nam-Chul Ha
- the Department of Agricultural Biotechnology, and Center for Food Safety and Toxicology, Seoul National University, Seoul 08826, Korea
| | - Sang Ho Choi
- From the National Research Laboratory of Molecular Microbiology and Toxicology and the Department of Agricultural Biotechnology, and Center for Food Safety and Toxicology, Seoul National University, Seoul 08826, Korea
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Singh PK, Kumar A. Mitochondria mediates caspase-dependent and independent retinal cell death in Staphylococcus aureus endophthalmitis. Cell Death Discov 2016; 2:16034. [PMID: 27551524 PMCID: PMC4979429 DOI: 10.1038/cddiscovery.2016.34] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 04/25/2016] [Accepted: 04/28/2016] [Indexed: 12/18/2022] Open
Abstract
Bacterial endophthalmitis, a vision-threatening complication of ocular surgery or trauma, is characterized by increased intraocular inflammation and retinal tissue damage. Although significant vision loss in endophthalmitis has been linked to retinal cell death, the underlying mechanisms of cell death remain elusive. In this study, using a mouse model of Staphylococcus aureus endophthalmitis and cultured human retinal Müller glia (MIO-M1 cell line), we demonstrate that S. aureus caused significant apoptotic cell death in the mouse retina and Müller glia, as evidenced by increased number of terminal dUTP nick end labeling and Annexin V and propidium iodide-positive cells. Immunohistochemistry and western blot studies revealed the reduction in mitochondrial membrane potential (JC-1 staining), release of cytochrome c into the cytosol, translocation of Bax to the mitochondria and the activation of caspase-9 and -3 in S. aureus-infected retina/retinal cells. In addition, the activation of PARP-1 and the release of apoptosis inducing factor from mitochondria was also observed in S. aureus-infected retinal cells. Inhibition studies using pan-caspase (Q-VD-OPH) and PARP-1 (DPQ) inhibitors showed significant reduction in S. aureus-induced retinal cell death both in vivo and in vitro. Together, our findings demonstrate that in bacterial endophthalmitis, retinal cells undergo apoptosis in the both caspase-dependent and independent manners, and mitochondria have a central role in this process. Hence, targeting the identified signaling pathways may provide the rationale to design therapeutic interventions to prevent bystander retinal tissue damage in bacterial endophthalmitis.
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Affiliation(s)
- P K Singh
- Kresge Eye Institute/Department of Ophthalmology, Wayne State University, Detroit, MI, USA
- Department of Anatomy and Cell Biology, Wayne State University, Detroit, MI, USA
| | - A Kumar
- Kresge Eye Institute/Department of Ophthalmology, Wayne State University, Detroit, MI, USA
- Department of Anatomy and Cell Biology, Wayne State University, Detroit, MI, USA
- Department of Immunology and Microbiology, Wayne State University, Detroit, MI, USA
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75
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Charvat RA, Arrizabalaga G. Oxidative stress generated during monensin treatment contributes to altered Toxoplasma gondii mitochondrial function. Sci Rep 2016; 6:22997. [PMID: 26976749 PMCID: PMC4792157 DOI: 10.1038/srep22997] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2015] [Accepted: 02/26/2016] [Indexed: 02/08/2023] Open
Abstract
The ionophore monensin displays potent activities against several coccidian parasites of veterinary and medical importance including the opportunistic pathogen of humans, Toxoplasma gondii. While monensin is used widely in animals, toxicity impedes its use in humans. Nonetheless, given its potency, understanding its mode of action would reveal vulnerable aspects of the parasite that can be exploited for drug development. We previously established that monensin induces Toxoplasma to undergo cell cycle arrest and an autophagy-like cell death. Interestingly, these effects are dependent on the mitochondrion-localized TgMSH-1 protein, suggesting that monensin disrupts mitochondrial function. We demonstrate that monensin treatment results in decreased mitochondrial membrane potential and altered morphology. These effects are mitigated by the antioxidant compound N-acetyl-cysteine suggesting that monensin causes an oxidative stress, which was indeed the case based on direct detection of reactive oxygen species. Moreover, over-expression of the antioxidant proteins glutaredoxin and peroxiredoxin 2 protect Toxoplasma from the deleterious effects of monensin. Thus, our studies show that the effects of monensin on Toxoplasma are due to a disruption of mitochondrial function caused by the induction of an oxidative stress and implicate parasite redox biology as a viable target for the development of drugs against Toxoplasma and related pathogenic parasites.
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Affiliation(s)
- Robert A Charvat
- Departments of Pharmacology and Toxicology Indiana University School of Medicine, Indianapolis, Indiana 46202, US
| | - Gustavo Arrizabalaga
- Departments of Pharmacology and Toxicology Indiana University School of Medicine, Indianapolis, Indiana 46202, US.,Departments of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana 46202, US
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76
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Zhang J, Liu Q, Chen W, Du G, Chen J. Short communication: Protection of lyophilized milk starter Lactobacillus casei Zhang by glutathione. J Dairy Sci 2016; 99:1846-1852. [DOI: 10.3168/jds.2015-9540] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Accepted: 08/16/2015] [Indexed: 11/19/2022]
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77
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Topaloglu N, Guney M, Aysan N, Gulsoy M, Yuksel S. The role of reactive oxygen species in the antibacterial photodynamic treatment: photoinactivation vs
proliferation. Lett Appl Microbiol 2016; 62:230-6. [DOI: 10.1111/lam.12538] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 11/27/2015] [Accepted: 12/08/2015] [Indexed: 11/30/2022]
Affiliation(s)
- N. Topaloglu
- Institute of Biomedical Engineering; Bogazici University; Istanbul Turkey
| | - M. Guney
- Institute of Biomedical Engineering; Bogazici University; Istanbul Turkey
- Department of Biomedical Engineering; Istanbul Medeniyet University; Istanbul Turkey
| | - N. Aysan
- Institute of Biomedical Engineering; Bogazici University; Istanbul Turkey
| | - M. Gulsoy
- Institute of Biomedical Engineering; Bogazici University; Istanbul Turkey
| | - S. Yuksel
- Molecular Biology and Genetics Department; Bogazici University; Istanbul Turkey
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78
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Nývltová E, Smutná T, Tachezy J, Hrdý I. OsmC and incomplete glycine decarboxylase complex mediate reductive detoxification of peroxides in hydrogenosomes of Trichomonas vaginalis. Mol Biochem Parasitol 2016; 206:29-38. [PMID: 26794804 DOI: 10.1016/j.molbiopara.2016.01.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 01/05/2016] [Accepted: 01/12/2016] [Indexed: 01/30/2023]
Abstract
Osmotically inducible protein (OsmC) and organic hydroperoxide resistance protein (Ohr) are small, thiol-dependent peroxidases that comprise a family of prokaryotic protective proteins central to the defense against deleterious effects of organic hydroperoxides, which are reactive molecules that are formed during interactions between the host immune system and pathogens. Trichomonas vaginalis, a sexually transmitted parasite of humans, possesses OsmC homologues in its hydrogenosomes, anaerobic mitochondrial organelles that harbor enzymes and pathways that are sensitive to oxidative damage. The glycine decarboxylase complex (GDC), which consists of four proteins (i.e., L, H, P and T), is in eukaryotes exclusively mitochondrial enzymatic system that catalyzes oxidative decarboxylation and deamination of glycine. However, trichomonad hydrogenosomes contain only the L and H proteins, whose physiological functions are unknown. Here, we found that the hydrogenosomal L and H proteins constitute a lipoate-dependent redox system that delivers electrons from reduced nicotinamide adenine dinucleotide (NADH) to OsmC for the reductive detoxification of peroxides. Our searches of genome databases revealed that, in addition to prokaryotes, homologues of OsmC/Ohr family proteins with predicted mitochondrial localization are present in various eukaryotic lineages. Therefore, we propose that the novel OsmC-GDC-based redox system may not be limited to T. vaginalis.
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Affiliation(s)
- Eva Nývltová
- Department of Parasitology, Charles University in Prague, Faculty of Science, Prague, Czech Republic
| | - Tamara Smutná
- Department of Parasitology, Charles University in Prague, Faculty of Science, Prague, Czech Republic
| | - Jan Tachezy
- Department of Parasitology, Charles University in Prague, Faculty of Science, Prague, Czech Republic
| | - Ivan Hrdý
- Department of Parasitology, Charles University in Prague, Faculty of Science, Prague, Czech Republic.
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79
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Xu J, Zhai J, Xu Y, Zhu J, Qin Y, Jiang D. A near-infrared fluorescent aza-bodipy probe for dual-wavelength detection of hydrogen peroxide in living cells. Analyst 2016; 141:2380-3. [DOI: 10.1039/c6an00262e] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A boronic acid functionalized aza-borondipyrromethene dye (azaBDPBA) was applied to the dual-wavelength detection of hydrogen peroxide with high selectivity, which was loaded into cells to indicate the alteration of intracellular hydrogen peroxide during biological processes.
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Affiliation(s)
- Jingjing Xu
- State Key Laboratory of Analytical Chemistry for Life Science
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing
- China
| | - Jingying Zhai
- State Key Laboratory of Analytical Chemistry for Life Science
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing
- China
| | - Yanmei Xu
- State Key Laboratory of Analytical Chemistry for Life Science
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing
- China
| | - Jingwei Zhu
- State Key Laboratory of Analytical Chemistry for Life Science
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing
- China
| | - Yu Qin
- State Key Laboratory of Analytical Chemistry for Life Science
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing
- China
| | - Dechen Jiang
- State Key Laboratory of Analytical Chemistry for Life Science
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing
- China
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80
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Antibiofilm Activity of Electrical Current in a Catheter Model. Antimicrob Agents Chemother 2015; 60:1476-80. [PMID: 26711752 DOI: 10.1128/aac.01628-15] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 12/07/2015] [Indexed: 01/23/2023] Open
Abstract
Catheter-associated infections are difficult to treat with available antimicrobial agents because of their biofilm etiology. We examined the effect of low-amperage direct electrical current (DC) exposure on established bacterial and fungal biofilms in a novel experimental in vitro catheter model. Staphylococcus epidermidis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida parapsilosis biofilms were grown on the inside surfaces of polyvinyl chloride (PVC) catheters, after which 0, 100, 200, or 500 μA of DC was delivered via intraluminally placed platinum electrodes. Catheter biofilms and intraluminal fluid were quantitatively cultured after 24 h and 4 days of DC exposure. Time- and dose-dependent biofilm killing was observed with all amperages and durations of DC administration. Twenty-four hours of 500 μA of DC sterilized the intraluminal fluid for all bacterial species studied; no viable bacteria were detected after treatment of S. epidermidis and S. aureus biofilms with 500 μA of DC for 4 days.
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81
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Yang E, Yi S, Bai F, Niu D, Zhong J, Wu Q, Chen S, Zhou R, Wang F. Cloning, Characterization and Expression Pattern Analysis of a Cytosolic Copper/Zinc Superoxide Dismutase (SaCSD1) in a Highly Salt Tolerant Mangrove (Sonneratia alba). Int J Mol Sci 2015; 17:ijms17010004. [PMID: 26703583 PMCID: PMC4730251 DOI: 10.3390/ijms17010004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 11/22/2015] [Accepted: 11/26/2015] [Indexed: 11/16/2022] Open
Abstract
Mangroves are critical marine resources for their remarkable ability to tolerate seawater. Antioxidant enzymes play an especially significant role in eliminating reactive oxygen species and conferring abiotic stress tolerance. In this study, a cytosolic copper/zinc superoxide dismutase (SaCSD1) cDNA of Sonneratia alba, a mangrove species with high salt tolerance, was successfully cloned and then expressed in Escherichia coli Rosetta-gami (designated as SaCSD1). SaCSD1 comprised a complete open reading frame (ORF) of 459 bp which encoded a protein of 152 amino acids. Its mature protein is predicted to be 15.32 kDa and the deduced isoelectric point is 5.78. SaCSD1 has high sequence similarity (85%-90%) with the superoxide dismutase (CSD) of some other plant species. SaCSD1 was expressed with 30.6% yield regarding total protein content after being introduced into the pET-15b (Sma I) vector for expression in Rosetta-gami and being induced with IPTG. After affinity chromatography on Ni-NTA, recombinant SaCSD1 was obtained with 3.2-fold purification and a specific activity of 2200 U/mg. SaCSD1 showed good activity as well as stability in the ranges of pH between 3 and 7 and temperature between 25 and 55 °C. The activity of recombinant SaCSD1 was stable in 0.25 M NaCl, Dimethyl Sulphoxide (DMSO), glycerol, and chloroform, and was reduced to a great extent in β-mercaptoethanol, sodium dodecyl sulfate (SDS), H₂O2, and phenol. Moreover, the SaCSD1 protein was very susceptive to pepsin digestion. Real-time Quantitative Polymerase Chain Reaction (PCR) assay demonstrated that SaCSD1 was expressed in leaf, stem, flower, and fruit organs, with the highest expression in fruits. Under 0.25 M and 0.5 M salt stress, the expression of SaCSD1 was down-regulated in roots, but up-regulated in leaves.
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Affiliation(s)
- Enze Yang
- College of Pharmacy, Jinan University, Guangzhou 510632, China.
- Guangdong Provincial Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research, Jinan University, Guangzhou 510632, China.
| | - Shanze Yi
- College of Pharmacy, Jinan University, Guangzhou 510632, China.
- Guangdong Provincial Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research, Jinan University, Guangzhou 510632, China.
| | - Fang Bai
- School of Life Sciences, Shenzhen University, Shenzhen 518060, China.
| | - Dewei Niu
- College of Pharmacy, Jinan University, Guangzhou 510632, China.
- Guangdong Provincial Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research, Jinan University, Guangzhou 510632, China.
| | - Junjie Zhong
- College of Pharmacy, Jinan University, Guangzhou 510632, China.
- Guangdong Provincial Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research, Jinan University, Guangzhou 510632, China.
| | - Qiuhong Wu
- College of Pharmacy, Jinan University, Guangzhou 510632, China.
- Guangdong Provincial Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research, Jinan University, Guangzhou 510632, China.
| | - Shufang Chen
- State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China.
| | - Renchao Zhou
- State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China.
| | - Feng Wang
- College of Pharmacy, Jinan University, Guangzhou 510632, China.
- Guangdong Provincial Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research, Jinan University, Guangzhou 510632, China.
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82
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Rabadi SM, Sanchez BC, Varanat M, Ma Z, Catlett SV, Melendez JA, Malik M, Bakshi CS. Antioxidant Defenses of Francisella tularensis Modulate Macrophage Function and Production of Proinflammatory Cytokines. J Biol Chem 2015; 291:5009-21. [PMID: 26644475 DOI: 10.1074/jbc.m115.681478] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Indexed: 11/06/2022] Open
Abstract
Francisella tularensis, the causative agent of a fatal human disease known as tularemia, has been used in the bioweapon programs of several countries in the past, and now it is considered a potential bioterror agent. Extreme infectivity and virulence of F. tularensis is due to its ability to evade immune detection and to suppress the host's innate immune responses. However, Francisella-encoded factors and mechanisms responsible for causing immune suppression are not completely understood. Macrophages and neutrophils generate reactive oxygen species (ROS)/reactive nitrogen species as a defense mechanism for the clearance of phagocytosed microorganisms. ROS serve a dual role; at high concentrations they act as microbicidal effector molecules that destroy intracellular pathogens, and at low concentrations they serve as secondary signaling messengers that regulate the expression of various inflammatory mediators. We hypothesized that the antioxidant defenses of F. tularensis maintain redox homeostasis in infected macrophages to prevent activation of redox-sensitive signaling components that ultimately result in suppression of pro-inflammatory cytokine production and macrophage microbicidal activity. We demonstrate that antioxidant enzymes of F. tularensis prevent the activation of redox-sensitive MAPK signaling components, NF-κB signaling, and the production of pro-inflammatory cytokines by inhibiting the accumulation of ROS in infected macrophages. We also report that F. tularensis inhibits ROS-dependent autophagy to promote its intramacrophage survival. Collectively, this study reveals novel pathogenic mechanisms adopted by F. tularensis to modulate macrophage innate immune functions to create an environment permissive for its intracellular survival and growth.
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Affiliation(s)
- Seham M Rabadi
- From the Department of Microbiology and Immunology, New York Medical College, Valhalla, New York 10595
| | - Belkys C Sanchez
- From the Department of Microbiology and Immunology, New York Medical College, Valhalla, New York 10595
| | - Mrudula Varanat
- From the Department of Microbiology and Immunology, New York Medical College, Valhalla, New York 10595
| | - Zhuo Ma
- the Department of Basic and Social Sciences, Albany College of Pharmacy and Health Sciences, Albany, New York 12208, and
| | - Sally V Catlett
- the Department of Basic and Social Sciences, Albany College of Pharmacy and Health Sciences, Albany, New York 12208, and
| | - Juan Andres Melendez
- the Colleges of Nanoscale Science and Engineering, State University of New York Polytechnic Institute, Albany, New York 12203
| | - Meenakshi Malik
- the Department of Basic and Social Sciences, Albany College of Pharmacy and Health Sciences, Albany, New York 12208, and
| | - Chandra Shekhar Bakshi
- From the Department of Microbiology and Immunology, New York Medical College, Valhalla, New York 10595,
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83
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Nouari W, Ysmail-Dahlouk L, Aribi M. Vitamin D3 enhances bactericidal activity of macrophage against Pseudomonas aeruginosa. Int Immunopharmacol 2015; 30:94-101. [PMID: 26655879 DOI: 10.1016/j.intimp.2015.11.033] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2015] [Revised: 11/07/2015] [Accepted: 11/25/2015] [Indexed: 12/22/2022]
Abstract
BACKGROUND The bioactive form of vitamin D3, i.e.1,25-dihydroxyvitamin D3 (1,25(OH)2D3) vitamin D has been shown to modulate monocytes/macrophages physiology and its response against bacterial infections. Pseudomonas aeruginosa (P. aeruginosa) is an opportunistic bacterial pathogen that can most frequently be fatal in immunocompromised infected people. METHODS We investigated the ex vivo effect of 1,25(OH)2D3 on monocyte-derived macrophages function against P. aeruginosa infection. RESULTS Relative vitamin D receptor (VDR) mRNA expression was significantly increased in infected and 1,25(OH)2D3-treated macrophages compared to controls (p<0.01). Treatment with 1,25(OH)2D3 markedly resulted in up-regulation of nitric oxide (NO) and IL-1β production and down-regulation of IL-10 levels (respectively, p=0.029, p=0.048 and p=0.008). Additionally, 1,25(OH)2D3 significantly increased M1/M2 macrophage ratio (p<0.05) and slightly reduced intracellular bacterial development. Furthermore, the arginase activity, P. aeruginosa phagocytosis and killing were significantly increased in cells that were both infected and 1,25(OH)2D3-treated compared to the infected, but not 1,25(OH)2D3-treated macrophages (respectively, p<0.001, p<0.01 and p<0.001). CONCLUSIONS We show in this study that bioactive from of vitamin D [1,25-dihydroxyvitamin D3 (1,25D3)] can enhance M1 macrophage polarization and their bactericidal protective activity against P. aeruginosa. Future works would involve improving the treatment response through dose-dependent effect studies, both in ex vivo and in vivo models.
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Affiliation(s)
- Wafa Nouari
- Laboratory of Applied Molecular Biology and Immunology, University of Tlemcen, 13000, Tlemcen, Algeria
| | - Lamia Ysmail-Dahlouk
- Laboratory of Applied Molecular Biology and Immunology, University of Tlemcen, 13000, Tlemcen, Algeria
| | - Mourad Aribi
- Laboratory of Applied Molecular Biology and Immunology, University of Tlemcen, 13000, Tlemcen, Algeria.
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84
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Portes JA, Souza TG, dos Santos TAT, da Silva LLR, Ribeiro TP, Pereira MD, Horn A, Fernandes C, DaMatta RA, de Souza W, Seabra SH. Reduction of Toxoplasma gondii Development Due to Inhibition of Parasite Antioxidant Enzymes by a Dinuclear Iron(III) Compound. Antimicrob Agents Chemother 2015; 59:7374-86. [PMID: 26392498 PMCID: PMC4649245 DOI: 10.1128/aac.00057-15] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Accepted: 07/22/2015] [Indexed: 11/20/2022] Open
Abstract
Toxoplasma gondii, the causative agent of toxoplasmosis, is an obligate intracellular protozoan that can infect a wide range of vertebrate cells. Here, we describe the cytotoxic effects of the dinuclear iron compound [Fe(HPCINOL)(SO4)]2-μ-oxo, in which HPCINOL is the ligand 1-(bis-pyridin-2-ylmethyl-amino)-3-chloropropan-2-ol, on T. gondii infecting LLC-MK2 host cells. This compound was not toxic to LLC-MK2 cells at concentrations of up to 200 μM but was very active against the parasite, with a 50% inhibitory concentration (IC50) of 3.6 μM after 48 h of treatment. Cyst formation was observed after treatment, as indicated by the appearance of a cyst wall, Dolichos biflorus lectin staining, and scanning and transmission electron microscopy characteristics. Ultrastructural changes were also seen in T. gondii, including membrane blebs and clefts in the cytoplasm, with inclusions similar to amylopectin granules, which are typically found in bradyzoites. An analysis of the cell death pathways in the parasite revealed that the compound caused a combination of apoptosis and autophagy. Fluorescence assays demonstrated that the redox environment in the LLC-MK2 cells becomes oxidant in the presence of the iron compound. Furthermore, a reduction in superoxide dismutase and catalase activities in the treated parasites and the presence of reactive oxygen species within the parasitophorous vacuoles were observed, indicating an impaired protozoan response against these radicals. These findings suggest that this compound disturbs the redox equilibrium of T. gondii, inducing cystogenesis and parasite death.
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Affiliation(s)
- J A Portes
- Laboratório de Tecnologia em Cultura de Células, Centro Universitário Estadual da Zona Oeste (UEZO), Rio de Janeiro, RJ, Brazil Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil
| | - T G Souza
- Laboratório de Tecnologia em Cultura de Células, Centro Universitário Estadual da Zona Oeste (UEZO), Rio de Janeiro, RJ, Brazil
| | - T A T dos Santos
- Laboratório de Tecnologia em Cultura de Células, Centro Universitário Estadual da Zona Oeste (UEZO), Rio de Janeiro, RJ, Brazil Laboratório de Biologia Celular e Tecidual, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, Rio de Janeiro, RJ, Brazil
| | - L L R da Silva
- Laboratório de Biologia Celular e Tecidual, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, Rio de Janeiro, RJ, Brazil
| | - T P Ribeiro
- Laboratório de Citotoxicidade e Genotoxicidade, Departamento de Bioquímica, Instituto de Química, UFRJ, Rio de Janeiro, RJ, Brazil
| | - M D Pereira
- Laboratório de Citotoxicidade e Genotoxicidade, Departamento de Bioquímica, Instituto de Química, UFRJ, Rio de Janeiro, RJ, Brazil
| | - A Horn
- Laboratório de Ciências Químicas, Centro de Ciência e Tecnologia, UENF, Campos dos Goytacazes, Rio de Janeiro, RJ, Brazil
| | - C Fernandes
- Laboratório de Ciências Químicas, Centro de Ciência e Tecnologia, UENF, Campos dos Goytacazes, Rio de Janeiro, RJ, Brazil
| | - R A DaMatta
- Laboratório de Biologia Celular e Tecidual, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, Rio de Janeiro, RJ, Brazil
| | - W de Souza
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem (INBEB) and Centro Nacional de Biologia Estrutural e Bioimagem (CENABIO), UFRJ, Rio de Janeiro, RJ, Brazil Instituto Nacional de Metrologia, Qualidade e Tecnologia (Inmetro), Duque de Caxias, RJ, Brazil
| | - S H Seabra
- Laboratório de Tecnologia em Cultura de Células, Centro Universitário Estadual da Zona Oeste (UEZO), Rio de Janeiro, RJ, Brazil
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85
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Differential induction of inflammatory cytokines and reactive oxygen species in murine peritoneal macrophages and resident fresh bone marrow cells by acute staphylococcus aureus infection: contribution of toll-like receptor 2 (TLR2). Inflammation 2015; 38:224-44. [PMID: 25266881 DOI: 10.1007/s10753-014-0026-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Among the known Toll-like receptors (TLRs), Toll-like receptor 2 (TLR2) is a key sensor for detecting Staphylococcus aureus invasion. But the function of TLR2 during S. aureus infection in different cell populations is unclear. Two different cell subtypes were chosen to study the interaction of S. aureus with TLR2 because macrophages are extremely different from one compartment to another and their capacity to respond to live bacteria or bacterial products differs from one site to another. The contribution of TLR2 to the host innate response against acute live S. aureus infection and heat-killed S. aureus (HKSA) using anti-TLR2 antibody in murine peritoneal macrophages and resident fresh bone marrow cells has been investigated here. TLR2 blocking before infection induces the release of interleukin (IL)-10 by macrophages thereby inhibiting excessive production of oxidants by activating antioxidant enzymes. TLR2-blocked peritoneal macrophages showed impaired release of tumor necrosis factor-alpha (TNF-α), interferon-gamma (IFN-γ) and IL-6 in response to both live and heat-killed S. aureus infection except bone marrow cells. TLR2-mediated free radical production and killing of S. aureus were modulated by TLR2 blocking in peritoneal macrophages and resident bone marrow cells. This study supported that S. aureus persists in resident bone marrow cells in a state of quiescence.
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86
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Reichhardt C, Ferreira JAG, Joubert LM, Clemons KV, Stevens DA, Cegelski L. Analysis of the Aspergillus fumigatus Biofilm Extracellular Matrix by Solid-State Nuclear Magnetic Resonance Spectroscopy. EUKARYOTIC CELL 2015; 14:1064-72. [PMID: 26163318 PMCID: PMC4621319 DOI: 10.1128/ec.00050-15] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 07/06/2015] [Indexed: 11/20/2022]
Abstract
Aspergillus fumigatus is commonly responsible for lethal fungal infections among immunosuppressed individuals. A. fumigatus forms biofilm communities that are of increasing biomedical interest due to the association of biofilms with chronic infections and their increased resistance to antifungal agents and host immune factors. Understanding the composition of microbial biofilms and the extracellular matrix is important to understanding function and, ultimately, to developing strategies to inhibit biofilm formation. We implemented a solid-state nuclear magnetic resonance (NMR) approach to define compositional parameters of the A. fumigatus extracellular matrix (ECM) when biofilms are formed in RPMI 1640 nutrient medium. Whole biofilm and isolated matrix networks were also characterized by electron microscopy, and matrix proteins were identified through protein gel analysis. The (13)C NMR results defined and quantified the carbon contributions in the insoluble ECM, including carbonyls, aromatic carbons, polysaccharide carbons (anomeric and nonanomerics), aliphatics, etc. Additional (15)N and (31)P NMR spectra permitted more specific annotation of the carbon pools according to C-N and C-P couplings. Together these data show that the A. fumigatus ECM produced under these growth conditions contains approximately 40% protein, 43% polysaccharide, 3% aromatic-containing components, and up to 14% lipid. These fundamental chemical parameters are needed to consider the relationships between composition and function in the A. fumigatus ECM and will enable future comparisons with other organisms and with A. fumigatus grown under alternate conditions.
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Affiliation(s)
| | - Jose A G Ferreira
- Department of Medicine, Division of Infectious Diseases and Geographic Medicine, Stanford University, Stanford, California, USA California Institute for Medical Research, San Jose, California, USA
| | - Lydia-Marie Joubert
- Cell Sciences Imaging Facility, Stanford University School of Medicine, Stanford, California, USA
| | - Karl V Clemons
- Department of Medicine, Division of Infectious Diseases and Geographic Medicine, Stanford University, Stanford, California, USA California Institute for Medical Research, San Jose, California, USA
| | - David A Stevens
- Department of Medicine, Division of Infectious Diseases and Geographic Medicine, Stanford University, Stanford, California, USA California Institute for Medical Research, San Jose, California, USA
| | - Lynette Cegelski
- Department of Chemistry, Stanford University, Stanford, California, USA
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87
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Singh V, Pal A, Darokar MP. A polyphenolic flavonoid glabridin: Oxidative stress response in multidrug-resistant Staphylococcus aureus. Free Radic Biol Med 2015; 87:48-57. [PMID: 26117328 DOI: 10.1016/j.freeradbiomed.2015.06.016] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 06/03/2015] [Accepted: 06/08/2015] [Indexed: 01/09/2023]
Abstract
Glabridin a polyphenolic flavonoid from Glycyrrhiza glabra is known to possess several therapeutic properties. In the present study, we report for the first time the in vitro antibacterial activity (MIC values ranging from 3.12 to 25 μg/mL) of glabridin against multidrug-resistant clinical isolates of S. aureus by inducing oxidative stress. Increased levels of H2O2 and NO were observed in a dose-dependent manner after treatment of glabridin that further affected macromolecules such as DNA, lipids, and proteins. Surprisingly, glabridin was found to possess antioxidant properties when used at lower concentrations using three different methods including DPPH, FRAP, and SOD assays. These observations were further validated through the expression analysis of oxidative stress-responsive genes using qRT-PCR wherein glabridin was observed to up- and down-regulate these genes at lower and higher concentrations, respectively. In in vitro combination experiments, glabridin was found to reduce the MIC of different antibiotics such as norfloxacin, oxacillin, and vancomycin by up to 4-fold, while the MIC of glabridin itself was found to be reduced by up to 8-fold in the presence of antibiotics. A synergistic interaction was observed between norfloxacin and glabridin when used in combination against multidrug-resistant clinical isolate SA 4627 of Staphylococcus aureus at much lower concentrations, indicating the suitability of glabridin in combination therapy.
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Affiliation(s)
- Vigyasa Singh
- Molecular Bioprospection Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow 226015, India
| | - Anirban Pal
- Molecular Bioprospection Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow 226015, India
| | - Mahendra P Darokar
- Molecular Bioprospection Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow 226015, India.
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88
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Antibiofilm Activity of Low-Amperage Continuous and Intermittent Direct Electrical Current. Antimicrob Agents Chemother 2015; 59:4610-5. [PMID: 26014944 DOI: 10.1128/aac.00483-15] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Accepted: 05/17/2015] [Indexed: 12/13/2022] Open
Abstract
Bacterial biofilms are difficult to treat using available antimicrobial agents, so new antibiofilm strategies are needed. We previously showed that 20, 200, and 2,000 μA of electrical current reduced bacterial biofilms of Staphylococcus aureus, Staphylococcus epidermidis, and Pseudomonas aeruginosa. Here, we tested continuous direct current at lower amperages, intermittent direct current, and combinations of surface materials (Teflon or titanium) and electrode compositions (stainless steel, graphite, titanium, or platinum) against S. aureus, S. epidermidis, and P. aeruginosa biofilms. In addition, we tested 200 or 2,000 μA for 1 and 4 days against biofilms of 33 strains representing 13 species of microorganisms. The logarithmic reduction factor was used to measure treatment effects. Using continuous current delivery, the lowest active amperage was 2 μA for 1, 4, or 7 days against P. aeruginosa and 5 μA for 7 days against S. epidermidis and S. aureus biofilms. Delivery of 200 μA for 4 h a day over 4 days reduced P. aeruginosa, S. aureus, and S. epidermidis biofilms on Teflon or titanium discs. A reduction of P. aeruginosa, S. aureus, and S. epidermidis biofilms was measured for 23 of 24 combinations of surface materials and electrode compositions tested. Four days of direct current delivery reduced biofilms of 25 of 33 strains studied. In conclusion, low-amperage current or 4 h a day of intermittent current delivered using a variety of electrode compositions reduced P. aeruginosa, S. aureus, and S. epidermidis biofilms on a variety of surface materials. The electricidal effect was observed against a majority of bacterial species studied.
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89
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Role of Oxidative RNA Damage in Chronic-Degenerative Diseases. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2015; 2015:358713. [PMID: 26078805 PMCID: PMC4452857 DOI: 10.1155/2015/358713] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Revised: 04/20/2015] [Accepted: 04/21/2015] [Indexed: 12/18/2022]
Abstract
Normal cellular metabolism and exposure to ionizing and ultraviolet radiations and exogenous agents produce reactive oxygen species (ROS). Due to their reactivity, they can interact with many critical biomolecules and induce cell damage. The reaction of ROS with free nucleobases, nucleosides, nucleotides, or oligonucleotides can generate numerous distinct modifications in nucleic acids. Oxidative damage to DNA has been widely investigated and is strongly implicated in the development of many chronic-degenerative diseases. In contrast, RNA damage is a poorly examined field in biomedical research. In this review, I discuss the importance of RNA as a target of oxidative damage and the role of oxidative damage to RNA in the pathogenesis of some chronic-degenerative diseases, such as neurological disorders, atherosclerosis, and cancer. Furthermore, I review recent evidence suggesting that RNA may be the target for toxic agents and indicating RNA degradation as a powerful tool to treat any pathology in which there is an aberrant expression of mRNA and/or its gene products.
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90
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Metabolic Response of Escherichia coli upon Treatment with Hypochlorite at Sub-Lethal Concentrations. PLoS One 2015; 10:e0125823. [PMID: 25932918 PMCID: PMC4416902 DOI: 10.1371/journal.pone.0125823] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 03/25/2015] [Indexed: 01/11/2023] Open
Abstract
Hypochlorite is a reactive oxygen species that is worldwide as an antibacterial disinfectant. Hypochlorite exposure is known to cause oxidative damage to DNA and proteins. As a response to these effects, the metabolite profiles of organisms treated with sub-lethal doses of hypochlorite are assumed to be severely modified; however, the nature of these changes is hardly understood. Therefore, using nuclear magnetic resonance spectroscopy and gas chromatography-coupled mass spectrometry, we analyzed the time-dependent impact of hypochlorite exposure with a sub-lethal concentration (50 µM) on the metabolite profile of the Escherichia coli strain MG1655. Principle component analysis clearly distinguished between the metabolite profiles of bacteria treated for 0, 5,10, 20, 40, or 60 min. Major changes in the relative amounts of fatty acids, acetic acid, and formic acid occurred within the first 5 min. Comparative gas chromatography-coupled mass spectrometry analyses revealed that the amounts of free methionine and alanine were significantly decreased in the treated cells, demonstrating their susceptibility to hypochlorite exposure. The concentrations of succinate, urea, orotic acid, 2-aminobutyric acid, and 2-hydroxybutyric acid were also severely affected, indicating general changes in the metabolic network by hypochlorite. However, most metabolite levels relaxed to the reference values of untreated cells after 40–60 min, reflecting the capability of E. coli to rapidly adapt to environmental stress factors such as the presence of sub-lethal oxidant levels.
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91
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Zhou Y, Pei W, Zhang X, Chen W, Wu J, Yao C, Huang L, Zhang H, Huang W, Chye Loo JS, Zhang Q. A cyanine-modified upconversion nanoprobe for NIR-excited imaging of endogenous hydrogen peroxide signaling in vivo. Biomaterials 2015; 54:34-43. [PMID: 25907037 DOI: 10.1016/j.biomaterials.2015.03.003] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Revised: 02/27/2015] [Accepted: 03/04/2015] [Indexed: 11/25/2022]
Abstract
Endogenous hydrogen peroxide is an important parameter associated with cellular signal transduction and homeostasis. However, abnormal H2O2 regulation in live systems has been implicated in many pathological conditions. Monitoring this signal in live systems is essential but challenging because current H2O2 probes are impractical for efficient bio-imaging due to UV/visible light as the excitation source. We herein present a novel design based on an organic fluorophore-attached lanthanide-doped upconversion nanoprobe (CYD1-UCNPs) for selective UCL detection of H2O2. This nanoprobe represents the next-generation imaging tool that features a robust UCL "turn-on" response to H2O2 with NIR-excited ratiometric signals and has potential applications in ratiometric UCL imaging of endogenous H2O2 generating in living cells and whole-body animals.
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Affiliation(s)
- Yi Zhou
- School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore
| | - Wenbo Pei
- Institute of Advanced Materials (IAM) and Jiangsu-Singapore Joint Research Center for Organic/Bio-Electronics & Information Displays, Nanjing Tech University (NanjingTech), Nanjing 211816, China
| | - Xiao Zhang
- School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore
| | - Wangqiao Chen
- School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore
| | - Jiansheng Wu
- School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore
| | - Cheng Yao
- College of Science, Nanjing Tech University (NanjingTech), Nanjing 211816, China
| | - Ling Huang
- Institute of Advanced Materials (IAM) and Jiangsu-Singapore Joint Research Center for Organic/Bio-Electronics & Information Displays, Nanjing Tech University (NanjingTech), Nanjing 211816, China
| | - Hua Zhang
- School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore
| | - Wei Huang
- Institute of Advanced Materials (IAM) and Jiangsu-Singapore Joint Research Center for Organic/Bio-Electronics & Information Displays, Nanjing Tech University (NanjingTech), Nanjing 211816, China
| | - Joachim Say Chye Loo
- School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore; Singapore Centre on Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, 637551, Singapore.
| | - Qichun Zhang
- School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore; Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore.
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92
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Association of myeloperoxidase polymorphism (G463A) with cervix cancer. Mol Cell Biochem 2015; 404:1-4. [DOI: 10.1007/s11010-015-2359-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Accepted: 02/14/2015] [Indexed: 10/24/2022]
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93
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The formation of Streptococcus mutans persisters induced by the quorum-sensing peptide pheromone is affected by the LexA regulator. J Bacteriol 2015; 197:1083-94. [PMID: 25583974 DOI: 10.1128/jb.02496-14] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The presence of multidrug-tolerant persister cells within microbial populations has been implicated in the resiliency of bacterial survival against antibiotic treatments and is a major contributing factor in chronic infections. The mechanisms by which these phenotypic variants are formed have been linked to stress response pathways in various bacterial species, but many of these mechanisms remain unclear. We have previously shown that in the cariogenic organism Streptococcus mutans, the quorum-sensing peptide CSP (competence-stimulating peptide) pheromone was a stress-inducible alarmone that triggered an increased formation of multidrug-tolerant persisters. In this study, we characterized SMU.2027, a CSP-inducible gene encoding a LexA ortholog. We showed that in addition to exogenous CSP exposure, stressors, including heat shock, oxidative stress, and ofloxacin antibiotic, were capable of triggering expression of lexA in an autoregulatory manner akin to that of LexA-like transcriptional regulators. We demonstrated the role of LexA and its importance in regulating tolerance toward DNA damage in a noncanonical SOS mechanism. We showed its involvement and regulatory role in the formation of persisters induced by the CSP-ComDE quorum-sensing regulatory system. We further identified key genes involved in sugar and amino acid metabolism, the clustered regularly interspaced short palindromic repeat (CRISPR) system, and autolysin from transcriptomic analyses that contribute to the formation of quorum-sensing-induced persister cells.
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94
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Abstract
O₂-generating reactions are exceedingly rare in biology and difficult to mimic synthetically. Perchlorate-respiring bacteria enzymatically detoxify chlorite (ClO₂(-) ), the end product of the perchlorate (ClO(4)(-) ) respiratory pathway, by rapidly converting it to dioxygen (O₂) and chloride (Cl(-)). This reaction is catalyzed by a heme-containing protein, called chlorite dismutase (Cld), which bears no structural or sequence relationships with known peroxidases or other heme proteins and is part of a large family of proteins with more than one biochemical function. The original assumptions from the 1990s that perchlorate is not a natural product and that perchlorate respiration might be confined to a taxonomically narrow group of species have been called into question, as have the roles of perchlorate respiration and Cld-mediated reactions in the global biogeochemical cycle of chlorine. In this chapter, the chemistry and biochemistry of Cld-mediated O₂generation, as well as the biological and geochemical context of this extraordinary reaction, are described.
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Affiliation(s)
- Jennifer L DuBois
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT, 59717, USA,
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95
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Briones-Martin-Del-Campo M, Orta-Zavalza E, Cañas-Villamar I, Gutiérrez-Escobedo G, Juárez-Cepeda J, Robledo-Márquez K, Arroyo-Helguera O, Castaño I, De Las Peñas A. The superoxide dismutases of Candida glabrata protect against oxidative damage and are required for lysine biosynthesis, DNA integrity and chronological life survival. MICROBIOLOGY-SGM 2014; 161:300-310. [PMID: 25479837 DOI: 10.1099/mic.0.000006] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The fungal pathogen Candida glabrata has a well-defined oxidative stress response, is extremely resistant to oxidative stress and can survive inside phagocytic cells. In order to further our understanding of the oxidative stress response in C. glabrata, we characterized the superoxide dismutases (SODs) Cu,ZnSOD (Sod1) and MnSOD (Sod2). We found that Sod1 is the major contributor to total SOD activity and is present in cytoplasm, whereas Sod2 is a mitochondrial protein. Both SODs played a central role in the oxidative stress response but Sod1 was more important during fermentative growth and Sod2 during respiration and growth in non-fermentable carbon sources. Interestingly, C. glabrata cells lacking both SODs showed auxotrophy for lysine, a high rate of spontaneous mutation and reduced chronological lifespan. Thus, our study reveals that SODs play an important role in metabolism, lysine biosynthesis, DNA protection and aging in C. glabrata.
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Affiliation(s)
- Marcela Briones-Martin-Del-Campo
- IPICYT, División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la Presa San José, no. 2055, Col. Lomas 4a Sección, San Luis Potosí, San Luis Potosí 78216, Mexico
| | - Emmanuel Orta-Zavalza
- IPICYT, División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la Presa San José, no. 2055, Col. Lomas 4a Sección, San Luis Potosí, San Luis Potosí 78216, Mexico
| | - Israel Cañas-Villamar
- IPICYT, División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la Presa San José, no. 2055, Col. Lomas 4a Sección, San Luis Potosí, San Luis Potosí 78216, Mexico
| | - Guadalupe Gutiérrez-Escobedo
- IPICYT, División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la Presa San José, no. 2055, Col. Lomas 4a Sección, San Luis Potosí, San Luis Potosí 78216, Mexico
| | - Jacqueline Juárez-Cepeda
- IPICYT, División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la Presa San José, no. 2055, Col. Lomas 4a Sección, San Luis Potosí, San Luis Potosí 78216, Mexico
| | - Karina Robledo-Márquez
- IPICYT, División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la Presa San José, no. 2055, Col. Lomas 4a Sección, San Luis Potosí, San Luis Potosí 78216, Mexico
| | - Omar Arroyo-Helguera
- IPICYT, División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la Presa San José, no. 2055, Col. Lomas 4a Sección, San Luis Potosí, San Luis Potosí 78216, Mexico
| | - Irene Castaño
- IPICYT, División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la Presa San José, no. 2055, Col. Lomas 4a Sección, San Luis Potosí, San Luis Potosí 78216, Mexico
| | - Alejandro De Las Peñas
- IPICYT, División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la Presa San José, no. 2055, Col. Lomas 4a Sección, San Luis Potosí, San Luis Potosí 78216, Mexico
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96
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Hui JGK, Mai-Prochnow A, Kjelleberg S, McDougald D, Rice SA. Environmental cues and genes involved in establishment of the superinfective Pf4 phage of Pseudomonas aeruginosa. Front Microbiol 2014; 5:654. [PMID: 25520708 PMCID: PMC4251444 DOI: 10.3389/fmicb.2014.00654] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Accepted: 11/13/2014] [Indexed: 11/21/2022] Open
Abstract
Biofilm development in Pseudomonas aeruginosa is in part dependent on a filamentous phage, Pf4, which contributes to biofilm maturation, cell death, dispersal and variant formation, e.g., small colony variants (SCVs). These biofilm phenotypes correlate with the conversion of the Pf4 phage into a superinfection (SI) variant that reinfects and kills the prophage carrying host, in contrast to other filamentous phage that normally replicate without killing their host. Here we have investigated the physiological cues and genes that may be responsible for this conversion. Flow through biofilms typically developed SI phage approximately days 4 or 5 of development and corresponded with dispersal. Starvation for carbon or nitrogen did not lead to the development of SI phage. In contrast, exposure of the biofilm to nitric oxide, H2O2 or the DNA damaging agent, mitomycin C, showed a trend of increased numbers of SI phage, suggesting that reactive oxygen or nitrogen species (RONS) played a role in the formation of SI phage. In support of this, mutation of oxyR, the major oxidative stress regulator in P. aeruginosa, resulted in higher level of and earlier superinfection compared to the wild-type (WT). Similarly, inactivation of mutS, a DNA mismatch repair gene, resulted in the early appearance of the SI phage and this was four log higher than the WT. In contrast, loss of recA, which is important for DNA repair and the SOS response, also resulted in a delayed and decreased production of SI phage. Treatments or mutations that increased superinfection also correlated with an increase in the production of morphotypic variants. The results suggest that the accumulation of RONS by the biofilm may result in DNA lesions in the Pf4 phage, leading to the formation of SI phage, which subsequently selects for morphotypic variants, such as SCVs.
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Affiliation(s)
- Janice G K Hui
- The Centre for Marine Bio-Innovation and the School of Biotechnology and Biomolecular Sciences, The University of New South Wales Sydney, NSW, Australia
| | - Anne Mai-Prochnow
- The Centre for Marine Bio-Innovation and the School of Biotechnology and Biomolecular Sciences, The University of New South Wales Sydney, NSW, Australia
| | - Staffan Kjelleberg
- The Centre for Marine Bio-Innovation and the School of Biotechnology and Biomolecular Sciences, The University of New South Wales Sydney, NSW, Australia ; The Singapore Centre on Environmental Life Sciences Engineering and The School of Biological Sciences, Nanyang Technological University Singapore, Republic of Singapore
| | - Diane McDougald
- The Centre for Marine Bio-Innovation and the School of Biotechnology and Biomolecular Sciences, The University of New South Wales Sydney, NSW, Australia ; The Singapore Centre on Environmental Life Sciences Engineering and The School of Biological Sciences, Nanyang Technological University Singapore, Republic of Singapore
| | - Scott A Rice
- The Centre for Marine Bio-Innovation and the School of Biotechnology and Biomolecular Sciences, The University of New South Wales Sydney, NSW, Australia ; The Singapore Centre on Environmental Life Sciences Engineering and The School of Biological Sciences, Nanyang Technological University Singapore, Republic of Singapore
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97
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Lim JG, Bang YJ, Choi SH. Characterization of the Vibrio vulnificus 1-Cys peroxiredoxin Prx3 and regulation of its expression by the Fe-S cluster regulator IscR in response to oxidative stress and iron starvation. J Biol Chem 2014; 289:36263-74. [PMID: 25398878 DOI: 10.1074/jbc.m114.611020] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Peroxiredoxins (Prxs) are ubiquitous antioxidant enzymes that reduce toxic peroxides. A new Vibrio vulnificus Prx, named Prx3, was identified and characterized in this study. Biochemical and mutational analyses revealed that Prx3 reduces H2O2, utilizing glutaredoxin 3 (Grx3) and glutathione (GSH) as reductants, and requires only N-terminal peroxidatic cysteine for its catalysis. These results, combined with the monomeric size of Prx3 observed under non-reducing conditions, suggested that Prx3 is a Grx3/GSH-dependent 1-Cys Prx and oxidized without forming intermolecular disulfide bonds. The prx3 mutation impaired growth in the medium containing peroxides and reduced virulence in mice, indicating that Prx3 is essential for survival under oxidative stress and pathogenesis of V. vulnificus. The Fe-S cluster regulator IscR activates prx3 by direct binding to a specific binding sequence centered at -44 from the transcription start site. The binding sequence was homologous to the Type 2 IscR-binding sequence, most likely recognized by the Fe-S clusterless apo-IscR in Escherichia coli. The iscR3CA mutant, chromosomally encoding the apo-locked IscR, exhibited 3-fold higher levels of activation of prx3 than the wild type and accumulated more IscR3CA protein in cells. The IscR-dependent activation of prx3 by aerobic growth and iron starvation was also associated with the increase in cellular levels of IscR protein. Taken together, the results suggested that IscR senses iron starvation as well as reactive oxygen species and shifts to the apo-form, which leads to the increase of cellular IscR and in turn prx3 expression, contributing to the survival and virulence of V. vulnificus during pathogenesis.
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Affiliation(s)
- Jong Gyu Lim
- From the National Research Laboratory of Molecular Microbiology and Toxicology, Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, Seoul National University, Seoul 151-921, South Korea
| | - Ye-Ji Bang
- From the National Research Laboratory of Molecular Microbiology and Toxicology, Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, Seoul National University, Seoul 151-921, South Korea
| | - Sang Ho Choi
- From the National Research Laboratory of Molecular Microbiology and Toxicology, Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, Seoul National University, Seoul 151-921, South Korea
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98
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Nishii W, Kukimoto-Niino M, Terada T, Shirouzu M, Muramatsu T, Kojima M, Kihara H, Yokoyama S. A redox switch shapes the Lon protease exit pore to facultatively regulate proteolysis. Nat Chem Biol 2014; 11:46-51. [PMID: 25383757 DOI: 10.1038/nchembio.1688] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 09/04/2014] [Indexed: 11/09/2022]
Abstract
The Lon AAA+ protease degrades damaged or misfolded proteins in its intramolecular chamber. Its activity must be precisely controlled, but the mechanism by which Lon is regulated in response to different environments is not known. Facultative anaerobes in the Enterobacteriaceae family, mostly symbionts and pathogens, encounter both anaerobic and aerobic environments inside and outside the host's body, respectively. The bacteria characteristically have two cysteine residues on the Lon protease (P) domain surface that unusually form a disulfide bond. Here we show that the cysteine residues act as a redox switch of Lon. Upon disulfide bond reduction, the exit pore of the P-domain ring narrows by ∼30%, thus interrupting product passage and decreasing activity by 80%; disulfide bonding by oxidation restores the pore size and activity. The redox switch (E°' = -227 mV) is appropriately tuned to respond to variation between anaerobic and aerobic conditions, thus optimizing the cellular proteolysis level for each environment.
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Affiliation(s)
- Wataru Nishii
- 1] RIKEN Systems and Structural Biology Center, Yokohama, Japan. [2] RIKEN Structural Biology Laboratory, Yokohama, Japan
| | - Mutsuko Kukimoto-Niino
- 1] RIKEN Systems and Structural Biology Center, Yokohama, Japan. [2] Division of Structural and Synthetic Biology, RIKEN Center for Life Science Technologies, Yokohama, Japan
| | - Takaho Terada
- 1] RIKEN Systems and Structural Biology Center, Yokohama, Japan. [2] RIKEN Structural Biology Laboratory, Yokohama, Japan
| | - Mikako Shirouzu
- 1] RIKEN Systems and Structural Biology Center, Yokohama, Japan. [2] Division of Structural and Synthetic Biology, RIKEN Center for Life Science Technologies, Yokohama, Japan
| | - Tomonari Muramatsu
- 1] RIKEN Systems and Structural Biology Center, Yokohama, Japan. [2] RIKEN Structural Biology Laboratory, Yokohama, Japan
| | - Masaki Kojima
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | | | - Shigeyuki Yokoyama
- 1] RIKEN Systems and Structural Biology Center, Yokohama, Japan. [2] RIKEN Structural Biology Laboratory, Yokohama, Japan
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99
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Abstract
Oral colonising bacteria are highly adapted to the various environmental niches harboured within the mouth, whether that means while contributing to one of the major oral diseases of caries, pulp infections, or gingival/periodontal disease or as part of a commensal lifestyle. Key to these infections is the ability to adhere to surfaces via a range of specialised adhesins targeted at both salivary and epithelial proteins, their glycans and to form biofilm. They must also resist the various physical stressors they are subjected to, including pH and oxidative stress. Possibly most strikingly, they have developed the ability to harvest both nutrient sources provided by the diet and those derived from the host, such as protein and surface glycans. We have attempted to review recent developments that have revealed much about the molecular mechanisms at work in shaping the physiology of oral bacteria and how we might use this information to design and implement new treatment strategies.
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Jang M, Cho EJ, Piao XL. Protective effects of resveratrol oligomers from Vitis amurensis against sodium nitroprusside-induced neurotoxicity in human neuroblastoma SH-SY5Y cells. Arch Pharm Res 2014; 38:1263-9. [DOI: 10.1007/s12272-014-0505-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2014] [Accepted: 10/17/2014] [Indexed: 12/17/2022]
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