1
|
Dubach VRA, San Segundo-Acosta P, Murphy BJ. Structural and mechanistic insights into Streptococcus pneumoniae NADPH oxidase. Nat Struct Mol Biol 2024:10.1038/s41594-024-01348-w. [PMID: 39039317 DOI: 10.1038/s41594-024-01348-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Accepted: 06/06/2024] [Indexed: 07/24/2024]
Abstract
Nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (NOXs) have a major role in the physiology of eukaryotic cells by mediating reactive oxygen species production. Evolutionarily distant proteins with the NOX catalytic core have been found in bacteria, including Streptococcus pneumoniae NOX (SpNOX), which is proposed as a model for studying NOXs because of its high activity and stability in detergent micelles. We present here cryo-electron microscopy structures of substrate-free and nicotinamide adenine dinucleotide (NADH)-bound SpNOX and of NADPH-bound wild-type and F397A SpNOX under turnover conditions. These high-resolution structures provide insights into the electron-transfer pathway and reveal a hydride-transfer mechanism regulated by the displacement of F397. We conducted structure-guided mutagenesis and biochemical analyses that explain the absence of substrate specificity toward NADPH and suggest the mechanism behind constitutive activity. Our study presents the structural basis underlying SpNOX enzymatic activity and sheds light on its potential in vivo function.
Collapse
Affiliation(s)
- Victor R A Dubach
- Redox and Metalloprotein Research Group, Max Planck Institute of Biophysics, Frankfurt am Main, Germany
- Redox and Metalloprotein Research Group, IMPRS on Cellular Biophysics, Frankfurt am Main, Germany
| | - Pablo San Segundo-Acosta
- Redox and Metalloprotein Research Group, Max Planck Institute of Biophysics, Frankfurt am Main, Germany.
- Chronic Disease Programme, UFIEC, Carlos III Health Institute, Madrid, Spain.
| | - Bonnie J Murphy
- Redox and Metalloprotein Research Group, Max Planck Institute of Biophysics, Frankfurt am Main, Germany.
| |
Collapse
|
2
|
Hernandez-Morfa M, Reinoso-Vizcaino NM, Zappia VE, Olivero NB, Cortes PR, Stempin CC, Perez DR, Echenique J. Intracellular Streptococcus pneumoniae develops enhanced fluoroquinolone persistence during influenza A coinfection. Front Microbiol 2024; 15:1423995. [PMID: 39035445 PMCID: PMC11258013 DOI: 10.3389/fmicb.2024.1423995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2024] [Accepted: 06/18/2024] [Indexed: 07/23/2024] Open
Abstract
Streptococcus pneumoniae is a major pathogen responsible for severe complications in patients with prior influenza A virus (IAV) infection. We have previously demonstrated that S. pneumoniae exhibits increased intracellular survival within IAV-infected cells. Fluoroquinolones (FQs) are widely used to treat pneumococcal infections. However, our prior work has shown that S. pneumoniae can develop intracellular FQ persistence, a phenomenon triggered by oxidative stress within host cells. This persistence allows the bacteria to withstand high FQ concentrations. In this study, we show that IAV infection enhances pneumococcal FQ persistence during intracellular survival within pneumocytes, macrophages, and neutrophils. This enhancement is partly due to increased oxidative stress induced by the viral infection. We find that this phenotype is particularly pronounced in autophagy-proficient host cells, potentially resulting from IAV-induced blockage of autophagosome-lysosome fusion. Moreover, we identified several S. pneumoniae genes involved in oxidative stress response that contribute to FQ persistence, including sodA (superoxide dismutase), clpL (chaperone), nrdH (glutaredoxin), and psaB (Mn+2 transporter component). Our findings reveal a novel mechanism of antibiotic persistence promoted by viral infection within host cells. This underscores the importance of considering this phenomenon when using FQs to treat pneumococcal infections, especially in patients with concurrent influenza A infection.
Collapse
Affiliation(s)
- Mirelys Hernandez-Morfa
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, Argentina
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Nicolas M. Reinoso-Vizcaino
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, Argentina
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Victoria E. Zappia
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, Argentina
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Nadia B. Olivero
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, Argentina
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Paulo R. Cortes
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, Argentina
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Cinthia C. Stempin
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, Argentina
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Daniel R. Perez
- Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Jose Echenique
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, Argentina
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| |
Collapse
|
3
|
Kareem BO, Gazioglu O, Mueller Brown K, Habtom M, Glanville DG, Oggioni MR, Andrew PW, Ulijasz AT, Hiller NL, Yesilkaya H. Environmental and genetic regulation of Streptococcus pneumoniae galactose catabolic pathways. Nat Commun 2024; 15:5171. [PMID: 38886409 PMCID: PMC11183247 DOI: 10.1038/s41467-024-49619-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 06/10/2024] [Indexed: 06/20/2024] Open
Abstract
Efficient utilization of nutrients is crucial for microbial survival and virulence. The same nutrient may be utilized by multiple catabolic pathways, indicating that the physical and chemical environments for induction as well as their functional roles may differ. Here, we study the tagatose and Leloir pathways for galactose catabolism of the human pathogen Streptococcus pneumoniae. We show that galactose utilization potentiates pneumococcal virulence, the induction of galactose catabolic pathways is influenced differentially by the concentration of galactose and temperature, and sialic acid downregulates galactose catabolism. Furthermore, the genetic regulation and in vivo induction of each pathway differ, and both galactose catabolic pathways can be turned off with a galactose analogue in a substrate-specific manner, indicating that galactose catabolic pathways can be potential drug targets.
Collapse
Affiliation(s)
- Banaz O Kareem
- Department of Respiratory Sciences, University of Leicester, Leicester, UK
- Department of Basic Medical Sciences, College of Medicine, University of Sulaimani, Sulaimani, Iraq
| | - Ozcan Gazioglu
- Department of Respiratory Sciences, University of Leicester, Leicester, UK
| | - Karina Mueller Brown
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Medhanie Habtom
- Department of Respiratory Sciences, University of Leicester, Leicester, UK
| | - David G Glanville
- Department of Microbiology and Immunology, Loyola University Chicago, Maywood, IL, USA
| | - Marco R Oggioni
- Department of Respiratory Sciences, University of Leicester, Leicester, UK
- Department of Pharmacy and Biotechnology, Bologna, Italy
| | - Peter W Andrew
- Department of Respiratory Sciences, University of Leicester, Leicester, UK
| | - Andrew T Ulijasz
- Department of Microbiology and Immunology, Loyola University Chicago, Maywood, IL, USA
| | - N Luisa Hiller
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Hasan Yesilkaya
- Department of Respiratory Sciences, University of Leicester, Leicester, UK.
| |
Collapse
|
4
|
Jiang W, Lin T, Pan J, Rivera CE, Tincher C, Wang Y, Zhang Y, Gao X, Wang Y, Tsui HCT, Winkler ME, Lynch M, Long H. Spontaneous mutations and mutational responses to penicillin treatment in the bacterial pathogen Streptococcus pneumoniae D39. MARINE LIFE SCIENCE & TECHNOLOGY 2024; 6:198-211. [PMID: 38827133 PMCID: PMC11136922 DOI: 10.1007/s42995-024-00220-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Accepted: 03/04/2024] [Indexed: 06/04/2024]
Abstract
Bacteria with functional DNA repair systems are expected to have low mutation rates due to strong natural selection for genomic stability. However, our study of the wild-type Streptococcus pneumoniae D39, a pathogen responsible for many common diseases, revealed a high spontaneous mutation rate of 0.02 per genome per cell division in mutation-accumulation (MA) lines. This rate is orders of magnitude higher than that of other non-mutator bacteria and is characterized by a high mutation bias in the A/T direction. The high mutation rate may have resulted from a reduction in the overall efficiency of selection, conferred by the tiny effective population size in nature. In line with this, S. pneumoniae D39 also exhibited the lowest DNA mismatch-repair (MMR) efficiency among bacteria. Treatment with the antibiotic penicillin did not elevate the mutation rate, as penicillin did not induce DNA damage and S. pneumoniae lacks a stress response pathway. Our findings suggested that the MA results are applicable to within-host scenarios and provide insights into pathogen evolution. Supplementary Information The online version contains supplementary material available at 10.1007/s42995-024-00220-6.
Collapse
Affiliation(s)
- Wanyue Jiang
- Institute of Evolution and Marine Biodiversity, KLMME, Ocean University of China, Qingdao, 266003 China
- Laboratory for Marine Biology and Biotechnology, Laoshan Laboratory, Qingdao, 266237 China
| | - Tongtong Lin
- Institute of Evolution and Marine Biodiversity, KLMME, Ocean University of China, Qingdao, 266003 China
| | - Jiao Pan
- Institute of Evolution and Marine Biodiversity, KLMME, Ocean University of China, Qingdao, 266003 China
| | - Caitlyn E. Rivera
- Department of Biology, Indiana University, Bloomington, IN 47405 USA
| | - Clayton Tincher
- Department of Biology, Indiana University, Bloomington, IN 47405 USA
| | - Yaohai Wang
- Institute of Evolution and Marine Biodiversity, KLMME, Ocean University of China, Qingdao, 266003 China
| | - Yu Zhang
- School of Mathematics Science, Ocean University of China, Qingdao, 266000 China
| | - Xiang Gao
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, School of Life Science, Shandong University, Qingdao, 266237 China
| | - Yan Wang
- Institute of Evolution and Marine Biodiversity, KLMME, Ocean University of China, Qingdao, 266003 China
| | - Ho-Ching T. Tsui
- Department of Biology, Indiana University, Bloomington, IN 47405 USA
| | | | - Michael Lynch
- Biodesign Center for Mechanisms of Evolution, Arizona State University, Tempe, AZ 85281 USA
| | - Hongan Long
- Institute of Evolution and Marine Biodiversity, KLMME, Ocean University of China, Qingdao, 266003 China
- Laboratory for Marine Biology and Biotechnology, Laoshan Laboratory, Qingdao, 266237 China
| |
Collapse
|
5
|
Ye C, Li Z, Ye C, Yuan L, Wu K, Zhu C. Association between Gut Microbiota and Biological Aging: A Two-Sample Mendelian Randomization Study. Microorganisms 2024; 12:370. [PMID: 38399774 PMCID: PMC10891714 DOI: 10.3390/microorganisms12020370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 02/08/2024] [Accepted: 02/09/2024] [Indexed: 02/25/2024] Open
Abstract
Recent observational studies revealed an association between gut microbiota and aging, but whether gut microbiota are causally associated with the aging process remains unknown. We used a two-sample Mendelian randomization approach to investigate the causal association between gut microbiota and biological age acceleration using the largest available gut microbiota GWAS summary data from the MiBioGen consortium and GWAS data on biological age acceleration. We further conducted sensitivity analysis using MR-PRESSO, MR-Egger regression, Cochran Q test, and reverse MR analysis. Streptococcus (IVW, β = 0.16, p = 0.0001) was causally associated with Bioage acceleration. Eubacterium (rectale group) (IVW, β = 0.20, p = 0.0190), Sellimonas (IVW, β = 0.06, p = 0.019), and Lachnospira (IVW, β = -0.18, p = 0.01) were suggestive of causal associations with Bioage acceleration, with the latter being protective. Actinomyces (IVW, β = 0.26, p = 0.0083), Butyricimonas (IVW, β = 0.21, p = 0.0184), and Lachnospiraceae (FCS020 group) (IVW, β = 0.24, p = 0.0194) were suggestive of causal associations with Phenoage acceleration. This Mendelian randomization study found that Streptococcus was causally associated with Bioage acceleration. Further randomized controlled trials are needed to investigate its role in the aging process.
Collapse
Affiliation(s)
- Chenglin Ye
- Department of Clinical Laboratory, Institute of Translational Medicine, Renmin Hospital of Wuhan University, Wuhan 430060, China; (C.Y.)
| | - Zhiqiang Li
- Department of Clinical Laboratory, Institute of Translational Medicine, Renmin Hospital of Wuhan University, Wuhan 430060, China; (C.Y.)
| | - Chun Ye
- Department of General Surgery, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065, China
| | - Li Yuan
- Department of Clinical Laboratory, Zhongnan Hospital of Wuhan University, Wuhan 430060, China
| | - Kailang Wu
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Chengliang Zhu
- Department of Clinical Laboratory, Institute of Translational Medicine, Renmin Hospital of Wuhan University, Wuhan 430060, China; (C.Y.)
| |
Collapse
|
6
|
Kemnitz N, Fuchs P, Remy R, Ruehrmund L, Bartels J, Klemenz AC, Trefz P, Miekisch W, Schubert JK, Sukul P. Effects of Contagious Respiratory Pathogens on Breath Biomarkers. Antioxidants (Basel) 2024; 13:172. [PMID: 38397770 PMCID: PMC10886173 DOI: 10.3390/antiox13020172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 01/17/2024] [Accepted: 01/23/2024] [Indexed: 02/25/2024] Open
Abstract
Due to their immediate exhalation after generation at the cellular/microbiome levels, exhaled volatile organic compounds (VOCs) may provide real-time information on pathophysiological mechanisms and the host response to infection. In recent years, the metabolic profiling of the most frequent respiratory infections has gained interest as it holds potential for the early, non-invasive detection of pathogens and the monitoring of disease progression and the response to therapy. Using previously unpublished data, randomly selected individuals from a COVID-19 test center were included in the study. Based on multiplex PCR results (non-SARS-CoV-2 respiratory pathogens), the breath profiles of 479 subjects with the presence or absence of flu-like symptoms were obtained using proton-transfer-reaction time-of-flight mass spectrometry. Among 223 individuals, one respiratory pathogen was detected in 171 cases, and more than one pathogen in 52 cases. A total of 256 subjects had negative PCR test results and had no symptoms. The exhaled VOC profiles were affected by the presence of Haemophilus influenzae, Streptococcus pneumoniae, and Rhinovirus. The endogenous ketone, short-chain fatty acid, organosulfur, aldehyde, and terpene concentrations changed, but only a few compounds exhibited concentration changes above inter-individual physiological variations. Based on the VOC origins, the observed concentration changes may be attributed to oxidative stress and antioxidative defense, energy metabolism, systemic microbial immune homeostasis, and inflammation. In contrast to previous studies with pre-selected patient groups, the results of this study demonstrate the broad inter-individual variations in VOC profiles in real-life screening conditions. As no unique infection markers exist, only concentration changes clearly above the mentioned variations can be regarded as indicative of infection or colonization.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | | | - Pritam Sukul
- Rostock Medical Breath Research Analytics and Technologies (ROMBAT), Department of Anaesthesiology, Intensive Care Medicine and Pain Therapy, University Medicine Rostock, 18057 Rostock, Germany
| |
Collapse
|
7
|
Bazant J, Ott B, Hudel M, Hain T, Lucas R, Mraheil MA. Impact of Endogenous Pneumococcal Hydrogen Peroxide on the Activity and Release of Pneumolysin. Toxins (Basel) 2023; 15:593. [PMID: 37888624 PMCID: PMC10611280 DOI: 10.3390/toxins15100593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 09/21/2023] [Accepted: 09/26/2023] [Indexed: 10/28/2023] Open
Abstract
Streptococcus pneumoniae is the leading cause of community-acquired pneumonia. The pore-forming cholesterol-dependent cytolysin (CDC) pneumolysin (PLY) and the physiological metabolite hydrogen peroxide (H2O2) can greatly increase the virulence of pneumococci. Although most studies have focused on the contribution of both virulence factors to the course of pneumococcal infection, it is unknown whether or how H2O2 can affect PLY activity. Of note, S. pneumoniae exploits endogenous H2O2 as an intracellular signalling molecule to modulate the activity of several proteins. Here, we demonstrate that H2O2 negatively affects the haemolytic activity of PLY in a concentration-dependent manner. Prevention of cysteine-dependent sulfenylation upon substitution of the unique and highly conserved cysteine residue to serine in PLY significantly reduces the toxin's susceptibility to H2O2 treatment and completely abolishes the ability of DTT to activate PLY. We also detect a clear gradual correlation between endogenous H2O2 generation and PLY release, with decreased H2O2 production causing a decline in the release of PLY. Comparative transcriptome sequencing analysis of the wild-type S. pneumoniae strain and three mutants impaired in H2O2 production indicates enhanced expression of several genes involved in peptidoglycan (PG) synthesis and in the production of choline-binding proteins (CPBs). One explanation for the impact of H2O2 on PLY release is the observed upregulation of the PG bridge formation alanyltransferases MurM and MurN, which evidentially negatively affect the PLY release. Our findings shed light on the significance of endogenous pneumococcal H2O2 in controlling PLY activity and release.
Collapse
Affiliation(s)
- Jasmin Bazant
- Institute of Medical Microbiology, German Center for Infection Research, Partner Site Giessen-Marburg-Langen, Justus-Liebig University Giessen, Schubertstrasse 81, 35392 Giessen, Germany; (J.B.); (B.O.); (M.H.); (T.H.)
| | - Benjamin Ott
- Institute of Medical Microbiology, German Center for Infection Research, Partner Site Giessen-Marburg-Langen, Justus-Liebig University Giessen, Schubertstrasse 81, 35392 Giessen, Germany; (J.B.); (B.O.); (M.H.); (T.H.)
| | - Martina Hudel
- Institute of Medical Microbiology, German Center for Infection Research, Partner Site Giessen-Marburg-Langen, Justus-Liebig University Giessen, Schubertstrasse 81, 35392 Giessen, Germany; (J.B.); (B.O.); (M.H.); (T.H.)
| | - Torsten Hain
- Institute of Medical Microbiology, German Center for Infection Research, Partner Site Giessen-Marburg-Langen, Justus-Liebig University Giessen, Schubertstrasse 81, 35392 Giessen, Germany; (J.B.); (B.O.); (M.H.); (T.H.)
| | - Rudolf Lucas
- Vascular Biology Center, Department of Pharmacology and Toxicology and Division of Pulmonary Critical Care Medicine, Medical College of Georgia at Augusta University, Augusta, GA 30912, USA;
| | - Mobarak Abu Mraheil
- Institute of Medical Microbiology, German Center for Infection Research, Partner Site Giessen-Marburg-Langen, Justus-Liebig University Giessen, Schubertstrasse 81, 35392 Giessen, Germany; (J.B.); (B.O.); (M.H.); (T.H.)
| |
Collapse
|
8
|
Fritsch VN, Linzner N, Busche T, Said N, Weise C, Kalinowski J, Wahl MC, Antelmann H. The MerR-family regulator NmlR is involved in the defense against oxidative stress in Streptococcus pneumoniae. Mol Microbiol 2023; 119:191-207. [PMID: 36349475 DOI: 10.1111/mmi.14999] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 10/25/2022] [Accepted: 10/30/2022] [Indexed: 11/11/2022]
Abstract
Streptococcus pneumoniae has to cope with the strong oxidant hypochlorous acid (HOCl), during host-pathogen interactions. Thus, we analyzed the global gene expression profile of S. pneumoniae D39 towards HOCl stress. In the RNA-seq transcriptome, the NmlR, SifR, CtsR, HrcA, SczA and CopY regulons and the etrx1-ccdA1-msrAB2 operon were most strongly induced under HOCl stress, which participate in the oxidative, electrophile and metal stress response in S. pneumoniae. The MerR-family regulator NmlR harbors a conserved Cys52 and controls the alcohol dehydrogenase-encoding adhC gene under carbonyl and NO stress. We demonstrated that NmlR senses also HOCl stress to activate transcription of the nmlR-adhC operon. HOCl-induced transcription of adhC required Cys52 of NmlR in vivo. Using mass spectrometry, NmlR was shown to be oxidized to intersubunit disulfides or S-glutathionylated under oxidative stress in vitro. A broccoli-FLAP-based assay further showed that both NmlR disulfides significantly increased transcription initiation at the nmlR promoter by RNAP in vitro, which depends on Cys52. Phenotype analyses revealed that NmlR functions in the defense against oxidative stress and promotes survival of S. pneumoniae during macrophage infections. In conclusion, NmlR was characterized as HOCl-sensing transcriptional regulator, which activates transcription of adhC under oxidative stress by thiol switches in S. pneumoniae.
Collapse
Affiliation(s)
| | - Nico Linzner
- Institute of Biology-Microbiology, Freie Universität Berlin, Berlin, Germany
| | - Tobias Busche
- Center for Biotechnology, University Bielefeld, Bielefeld, Germany.,NGS Core Facility, Medical School OWL, Bielefeld University, Bielefeld, Germany
| | - Nelly Said
- Laboratory of Structural Biochemistry, Freie Universität Berlin, Berlin, Germany
| | - Christoph Weise
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
| | - Jörn Kalinowski
- Center for Biotechnology, University Bielefeld, Bielefeld, Germany
| | - Markus C Wahl
- Laboratory of Structural Biochemistry, Freie Universität Berlin, Berlin, Germany.,Macromolecular Crystallography, Helmholtz-Zentrum Berlin für Materialien und Energie, Berlin, Germany
| | - Haike Antelmann
- Institute of Biology-Microbiology, Freie Universität Berlin, Berlin, Germany
| |
Collapse
|
9
|
Hernandez-Morfa M, Reinoso-Vizcaíno NM, Olivero NB, Zappia VE, Cortes PR, Jaime A, Echenique J. Host Cell Oxidative Stress Promotes Intracellular Fluoroquinolone Persisters of Streptococcus pneumoniae. Microbiol Spectr 2022; 10:e0436422. [PMID: 36445159 PMCID: PMC9769771 DOI: 10.1128/spectrum.04364-22] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 11/11/2022] [Indexed: 12/02/2022] Open
Abstract
Bacterial persisters represent a small subpopulation that tolerates high antibiotic concentrations without acquiring heritable resistance, and it may be generated by environmental factors. Here, we report the first antibiotic persistence mechanism in Streptococcus pneumoniae, which is induced by oxidative stress conditions and allows the pneumococcus to survive in the presence of fluoroquinolones. We demonstrated that fluoroquinolone persistence is prompted by both the impact of growth arrest and the oxidative stress response induced by H2O2 in bacterial cells. This process protected pneumococci against the deleterious effects of high ROS levels induced by fluoroquinolones. Importantly, S. pneumoniae develops persistence during infection, and is dependent on the oxidative stress status of the host cells, indicating that its transient intracellular life contributes to this mechanism. Furthermore, our findings suggest persistence may influence the outcome of antibiotic therapy and be part of a multistep mechanism in the evolution of fluoroquinolone resistance. IMPORTANCE In S. pneumoniae, different mechanisms that counteract antibiotic effects have been described, such as vancomycin tolerance, heteroresistance to penicillin and fluoroquinolone resistance, which critically affect the therapeutic efficacy. Antibiotic persistence is a type of antibiotic tolerance that allows a bacterial subpopulation to survive lethal antimicrobial concentrations. In this work, we used a host-cell infection model to reveal fluoroquinolone persistence in S. pneumoniae. This mechanism is induced by oxidative stress that the pneumococcus must overcome to survive in host cells. Many fluoroquinolones, such as levofloxacin and moxifloxacin, have a broad spectrum of activity against bacterial pathogens of community-acquired pneumonia, and they are used to treat pneumococcal diseases. However, the emergence of fluoroquinolone-resistant strains complicates antibiotic treatment of invasive infections. Consequently, antibiotic persistence in S. pneumoniae is clinically relevant due to prolonged exposure to fluoroquinolones likely favors the acquisition of mutations that generate antibiotic resistance in persisters. In addition, this work contributes to the knowledge of antibiotic persistence mechanisms in bacteria.
Collapse
Affiliation(s)
- Mirelys Hernandez-Morfa
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, Argentina
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Nicolás M. Reinoso-Vizcaíno
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, Argentina
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Nadia B. Olivero
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, Argentina
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Victoria E. Zappia
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, Argentina
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Paulo R. Cortes
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, Argentina
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Andrea Jaime
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, Argentina
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - José Echenique
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, Argentina
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| |
Collapse
|
10
|
Mitochondrial ROS production by neutrophils is required for host antimicrobial function against Streptococcus pneumoniae and is controlled by A2B adenosine receptor signaling. PLoS Pathog 2022; 18:e1010700. [DOI: 10.1371/journal.ppat.1010700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 11/28/2022] [Accepted: 11/07/2022] [Indexed: 11/15/2022] Open
Abstract
Polymorphonuclear cells (PMNs) control Streptococcus pneumoniae (pneumococcus) infection through various antimicrobial activities. We previously found that reactive oxygen species (ROS) were required for optimal antibacterial function, however, the NADPH oxidase is known to be dispensable for the ability of PMNs to kill pneumococci. In this study, we explored the role of ROS produced by the mitochondria in PMN antimicrobial defense against pneumococci. We found that the mitochondria are an important source of overall intracellular ROS produced by murine PMNs in response to infection. We investigated the host and bacterial factors involved and found that mitochondrial ROS (MitROS) are produced independent of bacterial capsule or pneumolysin but presence of live bacteria that are in direct contact with PMNs enhanced the response. We further found that MyD88-/- PMNs produced less MitROS in response to pneumococcal infection suggesting that released bacterial products acting as TLR ligands are sufficient for inducing MitROS production in PMNs. To test the role of MitROS in PMN function, we used an opsonophagocytic killing assay and found that MitROS were required for the ability of PMNs to kill pneumococci. We then investigated the role of MitROS in host resistance and found that MitROS are produced by PMNs in response to pneumococcal infection. Importantly, treatment of mice with a MitROS scavenger prior to systemic challenge resulted in reduced survival of infected hosts. In exploring host pathways that control MitROS, we focused on extracellular adenosine, which is known to control PMN anti-pneumococcal activity, and found that signaling through the A2B adenosine receptor inhibits MitROS production by PMNs. A2BR-/- mice produced more MitROS and were significantly more resistant to infection. Finally, we verified the clinical relevance of our findings using human PMNs. In summary, we identified a novel pathway that controls MitROS production by PMNs, shaping host resistance against S. pneumoniae.
Collapse
|
11
|
A newly identified flavoprotein disulfide reductase Har protects Streptococcus pneumoniae against hypothiocyanous acid. J Biol Chem 2022; 298:102359. [PMID: 35952759 PMCID: PMC9483559 DOI: 10.1016/j.jbc.2022.102359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 08/04/2022] [Accepted: 08/05/2022] [Indexed: 11/25/2022] Open
Abstract
Hypothiocyanous acid (HOSCN) is an antimicrobial oxidant produced from hydrogen peroxide and thiocyanate anions by heme peroxidases in secretory fluids such as in the human respiratory tract. Some respiratory tract pathogens display tolerance to this oxidant, which suggests that there might be therapeutic value in targeting HOSCN defense mechanisms. However, surprisingly little is known about how bacteria protect themselves from HOSCN. We hypothesized that tolerant pathogens have a flavoprotein disulfide reductase that uses NAD(P)H to directly reduce HOSCN, similar to thioredoxin reductase in mammalian cells. Here, we report the discovery of a previously uncharacterized flavoprotein disulfide reductase with HOSCN reductase activity, which we term Har (hypothiocyanous acid reductase), in Streptococcus pneumoniae, a bacterium previously found to be tolerant of HOSCN. S. pneumoniae generates large amounts of hydrogen peroxide that can be converted to HOSCN in the respiratory tract. Using deletion mutants, we demonstrate that the HOSCN reductase is dispensable for growth of S. pneumoniae in the presence of lactoperoxidase and thiocyanate. However, bacterial growth in the HOSCN-generating system was completely crippled when deletion of HOSCN reductase activity was combined with disruption of GSH import or recycling. Our findings identify a new bacterial HOSCN reductase and demonstrate a role for this protein in combination with GSH utilization to protect S. pneumoniae from HOSCN.
Collapse
|
12
|
Induction of the macrolide-resistance efflux pump Mega inhibits intoxication of Staphylococcus aureus strains by Streptococcus pneumoniae. Microbiol Res 2022; 263:127134. [PMID: 35905580 DOI: 10.1016/j.micres.2022.127134] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 07/06/2022] [Accepted: 07/13/2022] [Indexed: 11/21/2022]
Abstract
Streptococcus pneumoniae (Spn) kills Staphylococcus aureus (Sau) through a contact-dependent mechanism that is catalyzed by cations, including iron, to convert hydrogen peroxide (H2O2) to highly toxic hydroxyl radicals (•OH). There are two well-characterized ABC transporters that contribute to the pool of iron in Spn, named Pia and Piu. Some Spn strains have acquired genes mef(E)/mel encoding another ABC trasporter (Mega) that produces an inducible efflux pump for resistance to macrolides. In macrolide-resistant Spn clinical isolates the insertion of Mega class 1. IV and 2. IVc deleted the locus piaABCD and these strains were attenuated for intoxicating Sau. The goal of this study was to investigate if the disruption of iron acquisition, or the antimicrobial-resistance activity of Mega, contributed to inhibiting the killing mechanism. Neither depletion of iron with 2,2'-dipyridyl-d8 (DP) nor incubating with a double knockout mutant SpnΔpiaAΔpiuA, inhibited killing of Sau. Clinical Spn strains carrying Mega1. IV or Mega2. IVc showed a significant delay for killing Sau. An ex vivo recombination system was used to transfer Mega1. IV or Mega2. IVc to reference Spn strains, which was confirmed by whole genome sequencing, and recombinants TIGR4Mega2. IVc, D39Mega2. IVc, and D39Mega1. IV were delayed for killing Sau. We then compared Sau killing of selected Mega-carrying Spn strains when incubated with sub-inhibitory erythromycin (Mega-induced) or sub-inhibitory cefuroxime. Remarkably, killing of Sau was completely inhibited under the Mega-induced condition whereas incubation with cefuroxime did not interfere with killing. Both mef(E) and mel were upregulated > 400-fold, and spxB (encoding an enzyme responsible for production of most H2O2) was upregulated 14.2-fold, whereas transcription of the autolysin (lytA) gene was downregulated when incubated with erythromycin. We demonstrated that erythromycin induction of Mega inhibits the •OH-mediated intoxication of Sau and that the inhibition occurred at the post-translational level suggesting that an imbalance of ions in the membrane inhibits these reactions.
Collapse
|
13
|
Abstract
Regulated proteolysis is where AAA+ ATPases (ClpX, ClpC, and ClpE) are coupled to a protease subunit (ClpP) to facilitate degradation of misfolded and native regulatory proteins in the cell. The process is intricately linked to protein quality control and homeostasis and modulates several biological processes. In streptococci, regulated proteolysis is vital to various functions, including virulence expression, competence development, bacteriocin production, biofilm formation, and stress responses. Among the various Clp ATPases, ClpX is the major one that recognizes specific amino acid residues in its substrates and delivers them to the ClpP proteolytic chamber for degradation. While multiple ClpX substrates have been identified in Escherichia coli and other bacteria, little is known about the identity of these substrates in streptococci. Here, we used a preliminary proteomic analysis to identify putative ClpX substrates using Streptococcus mutans as a model organism. SMU.961 is one such putative substrate where we identified the Glu-Lue-Gln (ELQ) motif at the C terminus that is recognized by ClpX/P. We identified several other proteins, including MecA, which also harbor ELQ and are degraded by ClpX/P. This is surprising since MecA is known to be degraded by ClpC/P in Bacillus subtilis; however, ClpX/P-mediated MecA degradation is unknown. We also identified Glu and Gln as the crucial residues for ClpX recognition. Our data indicate a species and perhaps strain-specific recognition of ELQ by streptococcal ClpX/P. At present, we do not know whether this species-dependent degradation by ClpX/P is unique to S. mutans, and we are currently examining the phenomenon in other pathogenic streptococci. IMPORTANCE ClpX/P is a major intracellular proteolytic complex that is responsible for protein quality control in the cell. ClpX, an AAA+ ATPase, distinguishes the potential substrates by recognizing short motifs at the C-terminal end of proteins and delivers the substrates for degradation by ClpP protease. The identity of these ClpX substrates, which varies greatly among bacteria, is known only for a few well-studied species. Here, we used Streptococcus mutans as a model organism to identify ClpX substrates. We found that a short motif of three residues is successfully recognized by ClpX/P. Interestingly, the motif is not present at the ultimate C-terminal end; rather it is present close to the end. This result suggests that streptococcal ClpX ATPase can recognize internal motifs.
Collapse
|
14
|
Resistance of Streptococcus pneumoniae to hypothiocyanous acid generated by host peroxidases. Infect Immun 2022; 90:e0053021. [PMID: 35156851 DOI: 10.1128/iai.00530-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Streptococcus pneumoniae is a serious human respiratory pathogen. It generates hydrogen peroxide (H2O2) as part of its normal metabolism, yet it lacks enzymes that remove this oxidant. Here we show that lactoperoxidase and myeloperoxidase, two host enzymes present in the respiratory tract, convert bacterial H2O2 into HOSCN that S. pneumoniae can resist. We found that incubation of S. pneumoniae with myeloperoxidase in chloride-rich buffer killed the bacteria due to formation of toxic hypochlorous acid (HOCl). However, the addition of physiological concentrations of thiocyanate protected the bacteria. Similarly, S. pneumoniae remained viable in the presence of lactoperoxidase and thiocyanate even though the majority of bacterial H2O2 was converted to hypothiocyanous acid (HOSCN). S. pneumoniae and Pseudomonas aeruginosa, another respiratory pathogen, were similarly sensitive to H2O2 and HOCl. In contrast, S. pneumoniae tolerated much higher doses of HOSCN than P. aeruginosa. When associated with neutrophil extracellular traps (NETs), S. pneumoniae continued to generate H2O2, which was converted to HOCl by MPO present on NETs. However, there was no loss in bacterial viability because HOCl was scavenged by the NET proteins. We conclude that at sites of infection, bacteria will be protected from HOCl by thiocyanate and extracellular proteins including those associated with NETs. Resistance to HOSCN may give S. pneumoniae a survival advantage over other pathogenic bacteria. Understanding the mechanisms by which S. pneumoniae protects itself from HOSCN may reveal novel strategies for limiting the colonization and pathogenicity of this deadly pathogen.
Collapse
|
15
|
Shearer HL, Paton JC, Hampton MB, Dickerhof N. Glutathione utilization protects Streptococcus pneumoniae against lactoperoxidase-derived hypothiocyanous acid. Free Radic Biol Med 2022; 179:24-33. [PMID: 34923101 DOI: 10.1016/j.freeradbiomed.2021.12.261] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 12/01/2021] [Accepted: 12/14/2021] [Indexed: 12/31/2022]
Abstract
Streptococcus pneumoniae is the leading cause of community-acquired pneumonia, resulting in more than one million deaths each year worldwide. This pathogen generates large amounts of hydrogen peroxide (H2O2), which will be converted to hypothiocyanous acid (HOSCN) by lactoperoxidase (LPO) in the human respiratory tract. S. pneumoniae has been shown to be more resistant to HOSCN than some bacteria, and sensitizing S. pneumoniae to HOSCN may be a novel treatment strategy for combating this deadly pathogen. In this study we investigated the role of the low molecular weight thiol glutathione in HOSCN resistance. S. pneumoniae does not synthesize glutathione but imports it from the environment via an ABC transporter. Upon treatment of S. pneumoniae with HOSCN, bacterial glutathione was reversibly oxidized in a time- and dose-dependent manner, and intracellular proteins became glutathionylated. Bacterial death was observed when the reduced glutathione pool dropped below 20%. A S. pneumoniae mutant unable to import glutathione (ΔgshT) was more readily killed by exogenous HOSCN. Furthermore, bacterial growth in the presence of LPO converting bacterial H2O2 to HOSCN was significantly impeded in mutants that were unable to import glutathione, or mutants unable to recycle oxidized glutathione (Δgor). This research highlights the importance of glutathione in protecting S. pneumoniae from HOSCN. Limiting glutathione utilization by S. pneumoniae may be a way to limit colonization and pathogenicity.
Collapse
Affiliation(s)
- Heather L Shearer
- From the Centre for Free Radical Research, Department of Pathology and Biomedical Science, University of Otago Christchurch, Christchurch, New Zealand
| | - James C Paton
- Research Centre for Infectious Diseases, Department of Molecular and Biomedical Science, University of Adelaide, Australia
| | - Mark B Hampton
- From the Centre for Free Radical Research, Department of Pathology and Biomedical Science, University of Otago Christchurch, Christchurch, New Zealand
| | - Nina Dickerhof
- From the Centre for Free Radical Research, Department of Pathology and Biomedical Science, University of Otago Christchurch, Christchurch, New Zealand.
| |
Collapse
|
16
|
Vaillancourt K, Frenette M, Gottschalk M, Grenier D. Streptococcus pluranimalium 2N12 Exerts an Antagonistic Effect Against the Swine Pathogen Actinobacillus pleuropneumoniae by Producing Hydrogen Peroxide. Front Vet Sci 2021; 8:787241. [PMID: 34957284 PMCID: PMC8692661 DOI: 10.3389/fvets.2021.787241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 11/16/2021] [Indexed: 12/01/2022] Open
Abstract
Actinobacillus pleuropneumoniae is the causal agent of porcine pleuropneumonia, a highly contagious and often deadly respiratory disease that causes major economic losses in the swine industry worldwide. The aim of the present study was to investigate the hydrogen peroxide (H2O2)-dependent antagonistic activity of Streptococcus pluranimalium 2N12 (pig nasal isolate) against A. pleuropneumoniae. A fluorimetric assay showed that S. pluranimalium produces H2O2 dose- and time-dependently. The production of H2O2 increased in the presence of exogenous lactate, suggesting the involvement of lactate oxidase. All 20 strains of A. pleuropneumoniae tested, belonging to 18 different serovars, were susceptible to H2O2, with minimal inhibitory concentrations and minimal bactericidal concentrations ranging from 0.57 to 2.3 mM. H2O2, as well as a culture supernatant of S. pluranimalium, killed planktonic cells of A. pleuropneumoniae. Treating the culture supernatant with catalase abolished its bactericidal property. H2O2 was also active against a pre-formed biofilm-like structure of A. pleuropneumoniae albeit to a lesser extent. A checkerboard assay was used to show that there were antibacterial synergistic interactions between H2O2 and conventional antibiotics, more particularly ceftiofur. Based on our results and within the limitations of this in vitro study, the production of H2O2 by S. pluranimalium could be regarded as a potential protective mechanism of the upper respiratory tract against H2O2-sensitive pathogens such as A. pleuropneumoniae.
Collapse
Affiliation(s)
- Katy Vaillancourt
- Groupe de Recherche en Écologie Buccale, Faculté de Médecine Dentaire, Université Laval, Quebec City, QC, Canada
| | - Michel Frenette
- Groupe de Recherche en Écologie Buccale, Faculté de Médecine Dentaire, Université Laval, Quebec City, QC, Canada.,Centre de Recherche en Infectiologie Porcine et Avicole, Fonds de Recherche du Québec-Nature et Technologies, Saint-Hyacinthe, QC, Canada
| | - Marcelo Gottschalk
- Centre de Recherche en Infectiologie Porcine et Avicole, Fonds de Recherche du Québec-Nature et Technologies, Saint-Hyacinthe, QC, Canada.,Groupe de Recherche sur les Maladies Infectieuses du Porc, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, QC, Canada
| | - Daniel Grenier
- Groupe de Recherche en Écologie Buccale, Faculté de Médecine Dentaire, Université Laval, Quebec City, QC, Canada.,Centre de Recherche en Infectiologie Porcine et Avicole, Fonds de Recherche du Québec-Nature et Technologies, Saint-Hyacinthe, QC, Canada
| |
Collapse
|
17
|
Anil A, Apte S, Joseph J, Parthasarathy A, Madhavan S, Banerjee A. Pyruvate Oxidase as a Key Determinant of Pneumococcal Viability during Transcytosis across Brain Endothelium. J Bacteriol 2021; 203:e0043921. [PMID: 34606370 PMCID: PMC8604078 DOI: 10.1128/jb.00439-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 09/23/2021] [Indexed: 01/23/2023] Open
Abstract
Streptococcus pneumoniae invades a myriad of host tissues following efficient breaching of cellular barriers. However, strategies adopted by pneumococcus for evasion of host intracellular defenses governing successful transcytosis across host cellular barriers remain elusive. In this study, using brain endothelium as a model host barrier, we observed that pneumococcus containing endocytic vacuoles (PCVs), formed following S. pneumoniae internalization into brain microvascular endothelial cells (BMECs), undergo early maturation and acidification, with a major subset acquiring lysosome-like characteristics. Exploration of measures that would preserve pneumococcal viability in the lethal acidic pH of these lysosome-like vacuoles revealed a critical role of the two-component system response regulator, CiaR, which was previously implicated in induction of acid tolerance response. Pyruvate oxidase (SpxB), a key sugar-metabolizing enzyme that catalyzes oxidative decarboxylation of pyruvate to acetyl phosphate, was found to contribute to acid stress tolerance, presumably via acetyl phosphate-mediated phosphorylation and activation of CiaR, independent of its cognate kinase CiaH. Hydrogen peroxide, the by-product of an SpxB-catalyzed reaction, was also found to improve pneumococcal intracellular survival by oxidative inactivation of lysosomal cysteine cathepsins, thus compromising the degradative capacity of the host lysosomes. As expected, a ΔspxB mutant was found to be significantly attenuated in its ability to survive inside the BMEC endocytic vacuoles, reflecting its reduced transcytosis ability. Collectively, our studies establish SpxB as an important virulence determinant facilitating pneumococcal survival inside host cells, ensuring successful trafficking across host cellular barriers. IMPORTANCE Host cellular barriers have innate immune defenses to restrict microbial passage into sterile compartments. Here, by focusing on the blood-brain barrier endothelium, we investigated mechanisms that enable Streptococcus pneumoniae to traverse through host barriers. Pyruvate oxidase, a pneumococcal sugar-metabolizing enzyme, was found to play a crucial role in this via generation of acetyl phosphate and hydrogen peroxide. A two-pronged approach consisting of acetyl phosphate-mediated activation of acid tolerance response and hydrogen peroxide-mediated inactivation of lysosomal enzymes enabled pneumococci to maintain viability inside the degradative vacuoles of the brain endothelium for successful transcytosis across the barrier. Thus, pyruvate oxidase is a key virulence determinant and can potentially serve as a viable candidate for therapeutic interventions for better management of invasive pneumococcal diseases.
Collapse
Affiliation(s)
- Anjali Anil
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra, India
| | - Shruti Apte
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra, India
| | - Jincy Joseph
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra, India
| | - Akhila Parthasarathy
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra, India
| | - Shilpa Madhavan
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra, India
| | - Anirban Banerjee
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra, India
| |
Collapse
|
18
|
RNase Z Oxidative Degradation Impedes tRNA Maturation and is Involved in Streptococcal Translation Regulation in Response to Oxidative Stress. Microbiol Spectr 2021; 9:e0116721. [PMID: 34704809 PMCID: PMC8549757 DOI: 10.1128/spectrum.01167-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
When encountering oxidative stress, organisms selectively upregulate antioxidant genes and simultaneously suppress the translation of most other proteins. Eukaryotes employ multiple strategies to adjust translation at both the initiation and elongation stages; however, how prokaryotes modulate translation under oxidative stress remains unclear. Here, we report that upon hydrogen peroxide (H2O2) challenge, Streptococcus oligofermentans reduced translation via RNase Z (So-RNaseZ) oxidative degradation, thus hindering tRNA maturation. S. oligofermentans encodes all CCA-less tRNAs that require So-RNaseZ for 3′ end maturation. A combination of nonreducing SDS-PAGE and liquid chromatography/tandem mass spectrometry (LC/MS-MS) assays demonstrated that H2O2 oxidation induced Cys38-Cys149 disulfide linkages in recombinant So-RNaseZ protein, and serine substitution of Cys38 or Cys149 abolished these disulfide linkages. Consistently, redox Western blotting also determined intramolecular disulfide-linked So-RNaseZ in H2O2-treated S. oligofermentans cells. The disulfide-linked So-RNaseZ and monomer were both subject to proteolysis, whereas C149S mutation alleviated oxidative degradation of So-RNaseZ, suggesting that H2O2-mediated disulfide linkages substantially contributed to So-RNaseZ degradation. Accordingly, Northern blotting determined that tRNA precursor accumulation and mature tRNA species decrease in H2O2-treated S. oligofermentans. Moreover, reduced overall protein synthesis, as indicated by puromycin incorporation, and retarded growth of S. oligofermentans occurred in an H2O2 concentration-dependent manner. Overexpression of So-RNaseZ not only elevated tRNA precursor processing and protein synthesis but also partly rescued H2O2-suppressed S. oligofermentans growth. Moreover, So-RNaseZ oxidative degradation-mediated translation repression elevated S. oligofermentans survival under high H2O2 stress. Therefore, this work found that So-RNaseZ oxidative degradation-impeded tRNA maturation contributes to streptococcal translation repression and provides the oxidative stress adaptability for S. oligofermentans. IMPORTANCE Translation regulation is a common strategy used by organisms to reduce oxidative damage. Catalase-negative streptococci produce as well as tolerate high levels of H2O2. This work reports a novel translation regulation mechanism employed by Streptococcus oligofermentans in response to H2O2 challenge, in which the key tRNA endonuclease So-RNaseZ is oxidized to form Cys38-Cys149 disulfide linkages and both the disulfide-linked So-RNaseZ and monomers are subject to proteolysis; thus, tRNA maturation, protein translation, and growth are all suppressed. Notably, So-RNaseZ oxidative degradation-mediated translation repression offers oxidative adaptability to S. oligofermentans and enhances its survival against high H2O2 challenge. So-RNaseZ orthologs and H2O2-sensitive cysteines (Cys38 and Cys149) are widely distributed in Streptococcus and Lactococcus species genomes, which also encode all CCA-less tRNAs and lack catalase. Therefore, RNase Z oxidative degradation-based translation regulation could be widely employed by these lactic acid bacteria, including pathogenic streptococci, to cope with H2O2.
Collapse
|
19
|
A Novel Aquaporin Subfamily Imports Oxygen and Contributes to Pneumococcal Virulence by Controlling the Production and Release of Virulence Factors. mBio 2021; 12:e0130921. [PMID: 34399618 PMCID: PMC8406300 DOI: 10.1128/mbio.01309-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Aquaporins, integral membrane proteins widely distributed in organisms, facilitate the transport of water, glycerol, and other small uncharged solutes across cellular membranes and play important physiological roles in eukaryotes. However, characterizations and physiological functions of the prokaryotic aquaporins remain largely unknown. Here, we report that Streptococcus pneumoniae (pneumococcus) AqpC (Pn-AqpC), representing a new aquaporin subfamily possessing a distinct substrate-selective channel, functions as an oxygen porin by facilitating oxygen movement across the cell membrane and contributes significantly to pneumococcal virulence. The use of a phosphorescent oxygen probe showed that Pn-AqpC facilitates oxygen permeation into pneumococcal and Pn-AqpC-expressing yeast cells. Reconstituting Pn-AqpC into liposomes prepared with pneumococcal and Escherichia coli cellular membranes further verified that Pn-AqpC transports O2 but not water or glycerol. Alanine substitution showed that Pro232 in the substrate channel is key for Pn-AqpC in O2 transport. The deletion of Pn-aqpC significantly reduced H2O2 production and resistance to H2O2 and NO of pneumococci, whereas low-H2O2 treatment helped the ΔPn-aqpC mutant resist higher levels of H2O2 and even NO, indicating that Pn-AqpC-facilitated O2 permeation contributes to pneumococcal resistance to H2O2 and NO. Remarkably, the lack of Pn-aqpC alleviated cell autolysis, thus reducing pneumolysin (Ply) release and decreasing the hemolysis of pneumococci. Accordingly, the ΔPn-aqpC mutant markedly reduced survival in macrophages, decreased damage to macrophages, and significantly reduced lethality in mice. Therefore, the oxygen porin Pn-AqpC, through modulating H2O2 production and pneumolysin release, the two major pneumococcal virulence factors, controls the virulence of pneumococcus. Pn-AqpC orthologs are widely distributed in various pneumococcal serotypes, highlighting that the oxygen porin is important for pneumococcal pathogenicity.
Collapse
|
20
|
Green AE, Howarth D, Chaguza C, Echlin H, Langendonk RF, Munro C, Barton TE, Hinton JCD, Bentley SD, Rosch JW, Neill DR. Pneumococcal Colonization and Virulence Factors Identified Via Experimental Evolution in Infection Models. Mol Biol Evol 2021; 38:2209-2226. [PMID: 33502519 PMCID: PMC8136498 DOI: 10.1093/molbev/msab018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Streptococcus pneumoniae is a commensal of the human nasopharynx and a major cause of respiratory and invasive disease. We examined adaptation and evolution of pneumococcus, within nasopharynx and lungs, in an experimental system where the selective pressures associated with transmission were removed. This was achieved by serial passage of pneumococci, separately, in mouse models of nasopharyngeal carriage or pneumonia. Passaged pneumococci became more effective colonizers of the respiratory tract and we observed several examples of potential parallel evolution. The cell wall-modifying glycosyltransferase LafA was under strong selection during lung passage, whereas the surface expressed pneumococcal vaccine antigen gene pvaA and the glycerol-3-phosphate dehydrogenase gene gpsA were frequent targets of mutation in nasopharynx-passaged pneumococci. These mutations were not identified in pneumococci that were separately evolved by serial passage on laboratory agar. We focused on gpsA, in which the same single nucleotide polymorphism arose in two independently evolved nasopharynx-passaged lineages. We describe a new role for this gene in nasopharyngeal carriage and show that the identified single nucleotide change confers resistance to oxidative stress and enhanced nasopharyngeal colonization potential. We demonstrate that polymorphisms in gpsA arise and are retained during human colonization. These findings highlight how within-host environmental conditions can determine trajectories of bacterial evolution. Relative invasiveness or attack rate of pneumococcal lineages may be defined by genes that make niche-specific contributions to bacterial fitness. Experimental evolution in animal infection models is a powerful tool to investigate the relative roles played by pathogen virulence and colonization factors within different host niches.
Collapse
Affiliation(s)
- Angharad E Green
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Deborah Howarth
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Chrispin Chaguza
- Parasites and Microbes Programme, Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, United Kingdom
| | - Haley Echlin
- Department of Infectious Disease, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - R Frèdi Langendonk
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Connor Munro
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Thomas E Barton
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Jay C D Hinton
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Stephen D Bentley
- Parasites and Microbes Programme, Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, United Kingdom
| | - Jason W Rosch
- Department of Infectious Disease, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Daniel R Neill
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| |
Collapse
|
21
|
Mraheil MA, Toque HA, La Pietra L, Hamacher J, Phanthok T, Verin A, Gonzales J, Su Y, Fulton D, Eaton DC, Chakraborty T, Lucas R. Dual Role of Hydrogen Peroxide as an Oxidant in Pneumococcal Pneumonia. Antioxid Redox Signal 2021; 34:962-978. [PMID: 32283950 PMCID: PMC8035917 DOI: 10.1089/ars.2019.7964] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Significance:Streptococcus pneumoniae (Spn), a facultative anaerobic Gram-positive human pathogen with increasing rates of penicillin and macrolide resistance, is a major cause of lower respiratory tract infections worldwide. Pneumococci are a primary agent of severe pneumonia in children younger than 5 years and of community-acquired pneumonia in adults. A major defense mechanism toward Spn is the generation of reactive oxygen species, including hydrogen peroxide (H2O2), during the oxidative burst of neutrophils and macrophages. Paradoxically, Spn produces high endogenous levels of H2O2 as a strategy to promote colonization. Recent Advances: Pneumococci, which express neither catalase nor common regulators of peroxide stress resistance, have developed unique mechanisms to protect themselves from H2O2. Spn generates high levels of H2O2 as a strategy to promote colonization. Production of H2O2 moreover constitutes an important virulence phenotype and its cellular activities overlap and complement those of other virulence factors, such as pneumolysin, in modulating host immune responses and promoting organ injury. Critical Issues: This review examines the dual role of H2O2 in pneumococcal pneumonia, from the viewpoint of both the pathogen (defense mechanisms, lytic activity toward competing pathogens, and virulence) and the resulting host-response (inflammasome activation, endoplasmic reticulum stress, and damage to the alveolar-capillary barrier in the lungs). Future Directions: An understanding of the complexity of H2O2-mediated host-pathogen interactions is necessary to develop novel strategies that target these processes to enhance lung function during severe pneumonia.
Collapse
Affiliation(s)
- Mobarak Abu Mraheil
- Institute for Medical Microbiology, Justus-Liebig University, Giessen, Germany
| | - Haroldo A Toque
- Vascular Biology Center and Medical College of Georgia at Augusta University, Augusta, Georgia, USA.,Department of Pharmacology and Toxicology, Medical College of Georgia at Augusta University, Augusta, Georgia, USA
| | - Luigi La Pietra
- Institute for Medical Microbiology, Justus-Liebig University, Giessen, Germany
| | - Juerg Hamacher
- Internal Medicine and Pneumology, Lindenhofspital, Bern, Switzerland.,Lungen- und Atmungsstiftung Bern, Bern, Switzerland.,Internal Medicine V-Pneumology, Allergology, Respiratory and Environmental Medicine, Faculty of Medicine, Saarland University, Saarbrücken, Germany
| | - Tenzing Phanthok
- Department of Medicine, Medical College of Georgia at Augusta University, Augusta, Georgia, USA
| | - Alexander Verin
- Vascular Biology Center and Medical College of Georgia at Augusta University, Augusta, Georgia, USA.,Department of Medicine, Medical College of Georgia at Augusta University, Augusta, Georgia, USA
| | - Joyce Gonzales
- Department of Medicine, Medical College of Georgia at Augusta University, Augusta, Georgia, USA
| | - Yunchao Su
- Department of Pharmacology and Toxicology, Medical College of Georgia at Augusta University, Augusta, Georgia, USA
| | - David Fulton
- Vascular Biology Center and Medical College of Georgia at Augusta University, Augusta, Georgia, USA.,Department of Pharmacology and Toxicology, Medical College of Georgia at Augusta University, Augusta, Georgia, USA
| | - Douglas C Eaton
- Department of Medicine, Emory School of Medicine, Atlanta, Georgia, USA
| | - Trinad Chakraborty
- Institute for Medical Microbiology, Justus-Liebig University, Giessen, Germany
| | - Rudolf Lucas
- Vascular Biology Center and Medical College of Georgia at Augusta University, Augusta, Georgia, USA.,Department of Pharmacology and Toxicology, Medical College of Georgia at Augusta University, Augusta, Georgia, USA.,Department of Medicine, Medical College of Georgia at Augusta University, Augusta, Georgia, USA
| |
Collapse
|
22
|
Su T, Nakamoto R, Chun YY, Chua WZ, Chen JH, Zik JJ, Sham LT. Decoding capsule synthesis in Streptococcus pneumoniae. FEMS Microbiol Rev 2020; 45:6041728. [PMID: 33338218 DOI: 10.1093/femsre/fuaa067] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 12/07/2020] [Indexed: 12/20/2022] Open
Abstract
Streptococcus pneumoniae synthesizes more than one hundred types of capsular polysaccharides (CPS). While the diversity of the enzymes and transporters involved is enormous, it is not limitless. In this review, we summarized the recent progress on elucidating the structure-function relationships of CPS, the mechanisms by which they are synthesized, how their synthesis is regulated, the host immune response against them, and the development of novel pneumococcal vaccines. Based on the genetic and structural information available, we generated provisional models of the CPS repeating units that remain unsolved. In addition, to facilitate cross-species comparisons and assignment of glycosyltransferases, we illustrated the biosynthetic pathways of the known CPS in a standardized format. Studying the intricate steps of pneumococcal CPS assembly promises to provide novel insights for drug and vaccine development as well as improve our understanding of related pathways in other species.
Collapse
Affiliation(s)
- Tong Su
- Infectious Diseases Translational Research Programme, Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117545, Singapore
| | - Rei Nakamoto
- Infectious Diseases Translational Research Programme, Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117545, Singapore
| | - Ye Yu Chun
- Infectious Diseases Translational Research Programme, Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117545, Singapore
| | - Wan Zhen Chua
- Infectious Diseases Translational Research Programme, Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117545, Singapore
| | - Jia Hui Chen
- Infectious Diseases Translational Research Programme, Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117545, Singapore
| | - Justin J Zik
- Infectious Diseases Translational Research Programme, Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117545, Singapore
| | - Lok-To Sham
- Infectious Diseases Translational Research Programme, Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117545, Singapore
| |
Collapse
|
23
|
Gingerich AD, Doja F, Thomason R, Tóth E, Bradshaw JL, Douglass MV, McDaniel LS, Rada B. Oxidative killing of encapsulated and nonencapsulated Streptococcus pneumoniae by lactoperoxidase-generated hypothiocyanite. PLoS One 2020; 15:e0236389. [PMID: 32730276 PMCID: PMC7392276 DOI: 10.1371/journal.pone.0236389] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 07/06/2020] [Indexed: 01/04/2023] Open
Abstract
Streptococcus pneumoniae (Pneumococcus) infections affect millions of people worldwide, cause serious mortality and represent a major economic burden. Despite recent successes due to pneumococcal vaccination and antibiotic use, Pneumococcus remains a significant medical problem. Airway epithelial cells, the primary responders to pneumococcal infection, orchestrate an extracellular antimicrobial system consisting of lactoperoxidase (LPO), thiocyanate anion and hydrogen peroxide (H2O2). LPO oxidizes thiocyanate using H2O2 into the final product hypothiocyanite that has antimicrobial effects against a wide range of microorganisms. However, hypothiocyanite’s effect on Pneumococcus has never been studied. Our aim was to determine whether hypothiocyanite can kill S. pneumoniae. Bactericidal activity was measured in a cell-free in vitro system by determining the number of surviving pneumococci via colony forming units on agar plates, while bacteriostatic activity was assessed by measuring optical density of bacteria in liquid cultures. Our results indicate that hypothiocyanite generated by LPO exerted robust killing of both encapsulated and nonencapsulated pneumococcal strains. Killing of S. pneumoniae by a commercially available hypothiocyanite-generating product was even more pronounced than that achieved with laboratory reagents. Catalase, an H2O2 scavenger, inhibited killing of pneumococcal by hypothiocyanite under all circumstances. Furthermore, the presence of the bacterial capsule or lytA-dependent autolysis had no effect on hypothiocyanite-mediated killing of pneumococci. On the contrary, a pneumococcal mutant deficient in pyruvate oxidase (main bacterial H2O2 source) had enhanced susceptibility to hypothiocyanite compared to its wild-type strain. Overall, results shown here indicate that numerous pneumococcal strains are susceptible to LPO-generated hypothiocyanite.
Collapse
Affiliation(s)
- Aaron D. Gingerich
- Department of Infectious Diseases, College of Veterinary Medicine, The University of Georgia, Athens, Georgia, United States of America
| | - Fayhaa Doja
- Department of Infectious Diseases, College of Veterinary Medicine, The University of Georgia, Athens, Georgia, United States of America
| | - Rachel Thomason
- Department of Infectious Diseases, College of Veterinary Medicine, The University of Georgia, Athens, Georgia, United States of America
| | - Eszter Tóth
- Department of Infectious Diseases, College of Veterinary Medicine, The University of Georgia, Athens, Georgia, United States of America
| | - Jessica L. Bradshaw
- Department of Microbiology and Immunology, University of Mississippi Medical Center, Jackson, Mississippi, United States of America
| | - Martin V. Douglass
- Department of Infectious Diseases, College of Veterinary Medicine, The University of Georgia, Athens, Georgia, United States of America
| | - Larry S. McDaniel
- Department of Microbiology and Immunology, University of Mississippi Medical Center, Jackson, Mississippi, United States of America
| | - Balázs Rada
- Department of Infectious Diseases, College of Veterinary Medicine, The University of Georgia, Athens, Georgia, United States of America
- * E-mail:
| |
Collapse
|
24
|
Wang L, Sha Y, Wu D, Wei Q, Chen D, Yang S, Jia F, Yuan Q, Han X, Wang J. Surfactant induces ROS-mediated cell membrane permeabilization for the enhancement of mannatide production. Process Biochem 2020. [DOI: 10.1016/j.procbio.2019.12.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
|
25
|
Abstract
The catalase-negative streptococci produce as well as tolerate high levels of H2O2. This work reports the molecular mechanisms of low-H2O2-concentration-induced adaptation to higher H2O2 stress in a Streptococcus species, in which the peroxide-responsive repressor PerR and its redox regulons play the major role. Distinct from the Bacillus subtilis PerR, which is inactivated by H2O2 through histidine oxidation by the Fe2+-triggered Fenton reaction, the streptococcal PerR is inactivated by H2O2 oxidation of the structural Zn2+ binding cysteine residues and thus derepresses the expression of genes defending against oxidative stress. The reversible cysteine oxidation could provide flexibility for PerR regulation in streptococci, and the mechanism might be widely used by lactic acid bacteria, including pathogenic streptococci, containing high levels of cellular manganese, in coping with oxidative stress. The adaptation mechanism could also be applied in oral hygiene by facilitating the fitness and adaptability of the oral commensal streptococci to suppress the pathogens. Preexposure to a low concentration of H2O2 significantly increases the survivability of catalase-negative streptococci in the presence of a higher concentration of H2O2. However, the mechanisms of this adaptation remain unknown. Here, using a redox proteomics assay, we identified 57 and 35 cysteine-oxidized proteins in Streptococcus oligofermentans bacteria that were anaerobically cultured and then pulsed with 40 μM H2O2 and that were statically grown in a 40-ml culture, respectively. The oxidized proteins included the peroxide-responsive repressor PerR, the manganese uptake repressor MntR, thioredoxin system proteins Trx and Tpx, and most glycolytic proteins. Cysteine oxidations of these proteins were verified through redox Western blotting, immunoprecipitation, and liquid chromatography-tandem mass spectrometry assays. In particular, Zn2+-coordinated Cys139 and Cys142 mutations eliminated the H2O2 oxidation of PerR, and inductively coupled plasma mass spectrometry detected significantly decreased amounts of Zn2+ in H2O2-treated PerR, demonstrating that cysteine oxidation results in Zn2+ loss. An electrophoretic mobility shift assay (EMSA) determined that the DNA binding of Mn2+-bound PerR protein (PerR:Zn,Mn) was abolished by H2O2 treatment but was restored by dithiothreitol reduction, verifying that H2O2 inactivates streptococcal PerR:Zn,Mn through cysteine oxidation, analogous to the findings for MntR. Quantitative PCR and EMSA demonstrated that tpx, mntA, mntR, and dpr belonged to the PerR regulons but that only dpr was directly regulated by PerR; mntA was also controlled by MntR. Deletion of mntR significantly reduced the low-H2O2-concentration-induced adaptation of S. oligofermentans to a higher H2O2 concentration, while the absence of PerR completely abolished the self-protection. Therefore, a low H2O2 concentration resulted in the cysteine-reversible oxidations of PerR and MntR to derepress their regulons, which function in cellular metal and redox homeostasis and which endow streptococci with the antioxidative capability. This work reveals a novel Cys redox-based H2O2 defense strategy employed by catalase-negative streptococci in Mn2+-rich cellular environments. IMPORTANCE The catalase-negative streptococci produce as well as tolerate high levels of H2O2. This work reports the molecular mechanisms of low-H2O2-concentration-induced adaptation to higher H2O2 stress in a Streptococcus species, in which the peroxide-responsive repressor PerR and its redox regulons play the major role. Distinct from the Bacillus subtilis PerR, which is inactivated by H2O2 through histidine oxidation by the Fe2+-triggered Fenton reaction, the streptococcal PerR is inactivated by H2O2 oxidation of the structural Zn2+ binding cysteine residues and thus derepresses the expression of genes defending against oxidative stress. The reversible cysteine oxidation could provide flexibility for PerR regulation in streptococci, and the mechanism might be widely used by lactic acid bacteria, including pathogenic streptococci, containing high levels of cellular manganese, in coping with oxidative stress. The adaptation mechanism could also be applied in oral hygiene by facilitating the fitness and adaptability of the oral commensal streptococci to suppress the pathogens.
Collapse
|
26
|
Martínez SR, Aiassa V, Sola C, Becerra MC. Oxidative stress response in reference and clinical Staphylococcus aureus strains under Linezolid exposure. J Glob Antimicrob Resist 2020; 22:257-262. [PMID: 32169679 DOI: 10.1016/j.jgar.2020.02.032] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 02/12/2020] [Accepted: 02/21/2020] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Methicillin-resistant Staphylococcus aureus (MRSA) strains are some of the most widespread pathogens with multi-resistant to antimicrobial agents (AA). AA provoke several changes inside bacteria, which cannot be solely explained by the main mechanisms of action reported. OBJECTIVE The role of oxidative stress in bacteria exposed to bacteriostatic AA has not been widely studied; hence, the aim of our work was to investigate the effect of linezolid (LZD) on S. aureus strains. METHODS Oxidative stress markers, such as superoxide dismutase (SOD) enzyme activity, the global antioxidant response, advanced oxidation protein products (AOPP) and basal levels of glutathione in 28 clinical and 2 reference strains were measured. RESULTS AND CONCLUSIONS We identified 10 of 30 strains showing a slight increase in reactive species under LZD treatment with respect to the untreated control (between 22% and 56%). Higher generation was detected in clinical strains compared with the reference strains; however, the impact on the antioxidant response was not significant, and the oxidized protein levels were almost undetectable. The strains exposed to this oxazolidinone did not suffer acute oxidative stress. This is the first work reporting the behaviour of clinical and reference strains of S. aureus exposed to LZD, showing negligible oxidative stress.
Collapse
Affiliation(s)
- Sol Romina Martínez
- InstitutoMultidisciplinario de Biología Vegetal (IMBIV), CONICET and Departamento de Ciencias Farmacéuticas, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, X5000HUA Córdoba, Argentina.
| | - Virginia Aiassa
- Unidad de Investigación y Desarrollo en Tecnología Farmacéutica (UNITEFA), CONICET and Departamento de Ciencias Farmacéuticas, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, X5000HUA Córdoba, Argentina.
| | - Claudia Sola
- Departamento Bioquímica Clínica, Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI) CONICET, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, X5000HUA Córdoba, Argentina.
| | - María Cecilia Becerra
- InstitutoMultidisciplinario de Biología Vegetal (IMBIV), CONICET and Departamento de Ciencias Farmacéuticas, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, X5000HUA Córdoba, Argentina.
| |
Collapse
|
27
|
Du GF, Le YJ, Sun X, Yang XY, He QY. Proteomic investigation into the action mechanism of berberine against Streptococcus pyogenes. J Proteomics 2020; 215:103666. [DOI: 10.1016/j.jprot.2020.103666] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Revised: 12/16/2019] [Accepted: 01/22/2020] [Indexed: 12/12/2022]
|
28
|
Preston JA, Bewley MA, Marriott HM, McGarry Houghton A, Mohasin M, Jubrail J, Morris L, Stephenson YL, Cross S, Greaves DR, Craig RW, van Rooijen N, Bingle CD, Read RC, Mitchell TJ, Whyte MKB, Shapiro SD, Dockrell DH. Alveolar Macrophage Apoptosis-associated Bacterial Killing Helps Prevent Murine Pneumonia. Am J Respir Crit Care Med 2020; 200:84-97. [PMID: 30649895 DOI: 10.1164/rccm.201804-0646oc] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Rationale: Antimicrobial resistance challenges therapy of pneumonia. Enhancing macrophage microbicidal responses would combat this problem but is limited by our understanding of how alveolar macrophages (AMs) kill bacteria. Objectives: To define the role and mechanism of AM apoptosis-associated bacterial killing in the lung. Methods: We generated a unique CD68.hMcl-1 transgenic mouse with macrophage-specific overexpression of the human antiapoptotic Mcl-1 protein, a factor upregulated in AMs from patients at increased risk of community-acquired pneumonia, to address the requirement for apoptosis-associated killing. Measurements and Main Results: Wild-type and transgenic macrophages demonstrated comparable ingestion and initial phagolysosomal killing of bacteria. Continued ingestion (for ≥12 h) overwhelmed initial killing, and a second, late-phase microbicidal response killed viable bacteria in wild-type macrophages, but this response was blunted in CD68.hMcl-1 transgenic macrophages. The late phase of bacterial killing required both caspase-induced generation of mitochondrial reactive oxygen species and nitric oxide, the peak generation of which coincided with the late phase of killing. The CD68.hMcl-1 transgene prevented mitochondrial reactive oxygen species but not nitric oxide generation. Apoptosis-associated killing enhanced pulmonary clearance of Streptococcus pneumoniae and Haemophilus influenzae in wild-type mice but not CD68.hMcl-1 transgenic mice. Bacterial clearance was enhanced in vivo in CD68.hMcl-1 transgenic mice by reconstitution of apoptosis with BH3 mimetics or clodronate-encapsulated liposomes. Apoptosis-associated killing was not activated during Staphylococcus aureus lung infection. Conclusions: Mcl-1 upregulation prevents macrophage apoptosis-associated killing and establishes that apoptosis-associated killing is required to allow AMs to clear ingested bacteria. Engagement of macrophage apoptosis should be investigated as a novel, host-based antimicrobial strategy.
Collapse
Affiliation(s)
- Julie A Preston
- 1 The Florey Institute for Host-Pathogen Interactions and.,2 Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield Medical School, Sheffield, United Kingdom
| | - Martin A Bewley
- 1 The Florey Institute for Host-Pathogen Interactions and.,2 Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield Medical School, Sheffield, United Kingdom
| | - Helen M Marriott
- 1 The Florey Institute for Host-Pathogen Interactions and.,2 Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield Medical School, Sheffield, United Kingdom
| | - A McGarry Houghton
- 3 Clinical Research Division, Fred Hutchinson Cancer Research Center, and.,4 Division of Pulmonary and Critical Care Medicine, University of Washington, Seattle, Washington
| | - Mohammed Mohasin
- 5 Department of Biochemistry and Molecular Biology, University of Dhaka, Dhaka, Bangladesh
| | | | - Lucy Morris
- 1 The Florey Institute for Host-Pathogen Interactions and.,2 Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield Medical School, Sheffield, United Kingdom
| | - Yvonne L Stephenson
- 1 The Florey Institute for Host-Pathogen Interactions and.,2 Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield Medical School, Sheffield, United Kingdom
| | - Simon Cross
- 1 The Florey Institute for Host-Pathogen Interactions and.,2 Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield Medical School, Sheffield, United Kingdom.,7 Sheffield Teaching Hospitals, Sheffield, United Kingdom
| | - David R Greaves
- 8 Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Ruth W Craig
- 9 Department of Pharmacology and Toxicology, Geissel School of Medicine at Dartmouth, Hanover, New Hampshire
| | - Nico van Rooijen
- 10 Department of Molecular Cell Biology and Immunology, VU University Medical Center, Amsterdam, the Netherlands
| | - Colin D Bingle
- 1 The Florey Institute for Host-Pathogen Interactions and.,2 Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield Medical School, Sheffield, United Kingdom
| | - Robert C Read
- 11 University of Southampton Medical School, Southampton, United Kingdom.,12 National Institute for Health Research Southampton Biomedical Research Centre, Southampton, United Kingdom
| | - Timothy J Mitchell
- 13 Institute of Microbiology and Infection, School of Immunity and Infection, University of Birmingham, Birmingham, United Kingdom; and
| | - Moira K B Whyte
- 6 MRC Centre for Inflammation Research.,14 Department of Respiratory Medicine, and
| | - Steven D Shapiro
- 15 Division of Pulmonary, Allergy and Critical Care Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania
| | - David H Dockrell
- 6 MRC Centre for Inflammation Research.,16 Infection Medicine, University of Edinburgh, Edinburgh, United Kingdom
| |
Collapse
|
29
|
Siwapornchai N, Lee JN, Tchalla EYI, Bhalla M, Yeoh JH, Roggensack SE, Leong JM, Bou Ghanem EN. Extracellular adenosine enhances the ability of PMNs to kill Streptococcus pneumoniae by inhibiting IL-10 production. J Leukoc Biol 2020; 108:867-882. [PMID: 32017200 DOI: 10.1002/jlb.4ma0120-115rr] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 01/14/2020] [Accepted: 01/17/2020] [Indexed: 12/18/2022] Open
Abstract
Polymorphonuclear leukocytes (PMNs) are crucial for initial control of Streptococcus pneumoniae (pneumococcus) lung infection; however, as the infection progresses their persistence in the lungs becomes detrimental. Here we explored why the antimicrobial efficacy of PMNs declines over the course of infection. We found that the progressive inability of PMNs to control infection correlated with phenotypic differences characterized by a decrease in CD73 expression, an enzyme required for production of extracellular adenosine (EAD). EAD production by CD73 was crucial for the ability of both murine and human PMNs to kill S. pneumoniae. In exploring the mechanisms by which CD73 controlled PMN function, we found that CD73 mediated its antimicrobial activity by inhibiting IL-10 production. PMNs from wild-type mice did not increase IL-10 production in response to S. pneumoniae; however, CD73-/- PMNs up-regulated IL-10 production upon pneumococcal infection in vitro and during lung challenge. IL-10 inhibited the ability of WT PMNs to kill pneumococci. Conversely, blocking IL-10 boosted the bactericidal activity of CD73-/- PMNs as well as host resistance of CD73-/- mice to pneumococcal pneumonia. CD73/IL-10 did not affect apoptosis, bacterial uptake, and intracellular killing or production of antimicrobial neutrophil elastase and myeloperoxidase. Rather, inhibition of IL-10 production by CD73 was important for optimal reactive oxygen species (ROS) production by PMNs. ROS contributed to PMN antimicrobial function as their removal or detoxification impaired the ability of PMNs to efficiently kill S. pneumoniae. This study demonstrates that CD73 controls PMN antimicrobial phenotype during S. pneumoniae infection.
Collapse
Affiliation(s)
- Nalat Siwapornchai
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - James N Lee
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - Essi Y I Tchalla
- Department of Microbiology and Immunology, University at Buffalo School of Medicine, Buffalo, New York, USA
| | - Manmeet Bhalla
- Department of Microbiology and Immunology, University at Buffalo School of Medicine, Buffalo, New York, USA
| | - Jun Hui Yeoh
- Department of Microbiology and Immunology, University at Buffalo School of Medicine, Buffalo, New York, USA
| | - Sara E Roggensack
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - John M Leong
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - Elsa N Bou Ghanem
- Department of Microbiology and Immunology, University at Buffalo School of Medicine, Buffalo, New York, USA
| |
Collapse
|
30
|
Meng Y, Sheen CR, Magon NJ, Hampton MB, Dobson RCJ. Structure-function analyses of alkylhydroperoxidase D from Streptococcus pneumoniae reveal an unusual three-cysteine active site architecture. J Biol Chem 2020; 295:2984-2999. [PMID: 31974167 DOI: 10.1074/jbc.ra119.012226] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 01/19/2020] [Indexed: 12/12/2022] Open
Abstract
During aerobic growth, the Gram-positive facultative anaerobe and opportunistic human pathogen Streptococcus pneumoniae generates large amounts of hydrogen peroxide that can accumulate to millimolar concentrations. The mechanism by which this catalase-negative bacterium can withstand endogenous hydrogen peroxide is incompletely understood. The enzyme alkylhydroperoxidase D (AhpD) has been shown to contribute to pneumococcal virulence and oxidative stress responses in vivo We demonstrate here that SpAhpD exhibits weak thiol-dependent peroxidase activity and, unlike the previously reported Mycobacterium tuberculosis AhpC/D system, SpAhpD does not mediate electron transfer to SpAhpC. A 2.3-Å resolution crystal structure revealed several unusual structural features, including a three-cysteine active site architecture that is buried in a deep pocket, in contrast to the two-cysteine active site found in other AhpD enzymes. All single-cysteine SpAhpD variants remained partially active, and LC-MS/MS analyses revealed that the third cysteine, Cys-163, formed disulfide bonds with either of two cysteines in the canonical Cys-78-X-X-Cys-81 motif. We observed that SpAhpD formed a dimeric quaternary structure both in the crystal and in solution, and that the highly conserved Asn-76 of the AhpD core motif is important for SpAhpD folding. In summary, SpAhpD is a weak peroxidase and does not transfer electrons to AhpC, and therefore does not fit existing models of bacterial AhpD antioxidant defense mechanisms. We propose that it is unlikely that SpAhpD removes peroxides either directly or via AhpC, and that SpAhpD cysteine oxidation may act as a redox switch or mediate electron transfer with other thiol proteins.
Collapse
Affiliation(s)
- Yanxiang Meng
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, Christchurch 8041, New Zealand
| | - Campbell R Sheen
- Callaghan Innovation, University of Canterbury, Christchurch 8041, New Zealand
| | - Nicholas J Magon
- Centre for Free Radical Research, Department of Pathology and Biomedical Science, University of Otago, Christchurch 8011, New Zealand
| | - Mark B Hampton
- Centre for Free Radical Research, Department of Pathology and Biomedical Science, University of Otago, Christchurch 8011, New Zealand.
| | - Renwick C J Dobson
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, Christchurch 8041, New Zealand; Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria 3010, Australia.
| |
Collapse
|
31
|
Tóthpál A, Desobry K, Joshi SS, Wyllie AL, Weinberger DM. Variation of growth characteristics of pneumococcus with environmental conditions. BMC Microbiol 2019; 19:304. [PMID: 31878880 PMCID: PMC6933730 DOI: 10.1186/s12866-019-1671-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 12/02/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Pneumococcus is exposed to a variety of temperature and oxygen levels in the upper respiratory tract and as it invades the lung, tissues, and blood. We sought to determine the effect of environmental variability on growth in vitro and to assess variability between strains. We evaluated the effect of temperature and oxygen on the growth of 256 isolates representing 53 serotypes, recovered from healthy carriers and disease patients. Strains were grown at a range of temperatures, anaerobically or in ambient air with catalase, and were monitored by reading the optical density. Regression models evaluated variation in the characteristics of the growth curves. RESULTS Most isolates grew to the maximal density at low temperatures (~33C) and under aerobic conditions. There was considerable variability between strains, and some of this variability was linked to serotype. However, capsule-switch experiments suggest that the production of different capsules might not be sufficient to explain this variation, suggesting there could be interactions between the capsule and genetic background. CONCLUSIONS Pneumococcal strains vary in how they respond to environmental variations, some of this variation can be explained by the capsule type being produced, but capsule production itself is not sufficient to explain the variability. This variability could help to explain why different lineages of pneumococcus are more common in carriage or disease.
Collapse
Affiliation(s)
- Adrienn Tóthpál
- Epidemiology of Microbial Diseases, Yale School of Public Health, 60 College Street, New Haven, CT, 06510, USA. .,Institute of Medical Microbiology, Semmelweis University, Nagyvarad ter 4, Budapest, HU-1089, Hungary.
| | - Katherine Desobry
- Epidemiology of Microbial Diseases, Yale School of Public Health, 60 College Street, New Haven, CT, 06510, USA
| | - Shreyas S Joshi
- Epidemiology of Microbial Diseases, Yale School of Public Health, 60 College Street, New Haven, CT, 06510, USA
| | - Anne L Wyllie
- Epidemiology of Microbial Diseases, Yale School of Public Health, 60 College Street, New Haven, CT, 06510, USA
| | - Daniel M Weinberger
- Epidemiology of Microbial Diseases, Yale School of Public Health, 60 College Street, New Haven, CT, 06510, USA.
| |
Collapse
|
32
|
Wu X, Gordon O, Jiang W, Antezana BS, Angulo-Zamudio UA, Del Rio C, Moller A, Brissac T, Tierney ARP, Warncke K, Orihuela CJ, Read TD, Vidal JE. Interaction between Streptococcus pneumoniae and Staphylococcus aureus Generates ·OH Radicals That Rapidly Kill Staphylococcus aureus Strains. J Bacteriol 2019; 201:e00474-19. [PMID: 31405914 PMCID: PMC6779455 DOI: 10.1128/jb.00474-19] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 08/08/2019] [Indexed: 12/26/2022] Open
Abstract
Streptococcus pneumoniae rapidly kills Staphylococcus aureus by producing membrane-permeable hydrogen peroxide (H2O2). The mechanism by which S. pneumoniae-produced H2O2 mediates S. aureus killing was investigated. An in vitro model that mimicked S. pneumoniae-S. aureus contact during colonization of the nasopharynx demonstrated that S. aureus killing required outcompeting densities of S. pneumoniae Compared to the wild-type strain, isogenic S. pneumoniae ΔlctO and S. pneumoniae ΔspxB, both deficient in production of H2O2, required increased density to kill S. aureus While residual H2O2 activity produced by single mutants was sufficient to eradicate S. aureus, an S. pneumoniae ΔspxB ΔlctO double mutant was unable to kill S. aureus A collection of 20 diverse methicillin-resistant S. aureus (MRSA) and methicillin-susceptible S. aureus (MSSA) strains showed linear sensitivity (R2 = 0.95) for S. pneumoniae killing, but the same strains had different susceptibilities when challenged with pure H2O2 (5 mM). There was no association between the S. aureus clonal complex and sensitivity to either S. pneumoniae or H2O2 To kill S. aureus, S. pneumoniae produced ∼180 μM H2O2 within 4 h of incubation, while the killing-defective S. pneumoniae ΔspxB and S. pneumoniae ΔspxB ΔlctO mutants produced undetectable levels. Remarkably, a sublethal dose (1 mM) of pure H2O2 incubated with S. pneumoniae ΔspxB eradicated diverse S. aureus strains, suggesting that S. pneumoniae bacteria may facilitate conversion of H2O2 to a hydroxyl radical (·OH). Accordingly, S. aureus killing was completely blocked by incubation with scavengers of ·OH radicals, dimethyl sulfoxide (Me2SO), thiourea, or sodium salicylate. The ·OH was detected in S. pneumoniae cells by spin trapping and electron paramagnetic resonance. Therefore, S. pneumoniae produces H2O2, which is rapidly converted to a more potent oxidant, hydroxyl radicals, to rapidly intoxicate S. aureus strains.IMPORTANCEStreptococcus pneumoniae strains produce hydrogen peroxide (H2O2) to kill bacteria in the upper airways, including pathogenic Staphylococcus aureus strains. The targets of S. pneumoniae-produced H2O2 have not been discovered, in part because of a lack of knowledge about the underlying molecular mechanism. We demonstrated that an increased density of S. pneumoniae kills S. aureus by means of H2O2 produced by two enzymes, SpxB and LctO. We discovered that SpxB/LctO-produced H2O2 is converted into a hydroxyl radical (·OH) that rapidly intoxicates and kills S. aureus We successfully inhibited the toxicity of ·OH with three different scavengers and detected ·OH in the supernatant. The target(s) of the hydroxyl radicals represents a new alternative for the development of antimicrobials against S. aureus infections.
Collapse
Affiliation(s)
- Xueqing Wu
- Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
- Department of Infectious Disease, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Oren Gordon
- Department of Pediatrics, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Wenxin Jiang
- Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
| | - Brenda S Antezana
- Graduate Program in Microbiology and Molecular Genetics, Emory University, Atlanta, Georgia, USA
| | - Uriel A Angulo-Zamudio
- Regional Program for the Doctorate in Biotechnology, Faculty of Chemical Sciences Biological, Autonomous University of Sinaloa, Sinaloa, Mexico
| | - Carlos Del Rio
- Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
| | - Abraham Moller
- Graduate Program in Microbiology and Molecular Genetics, Emory University, Atlanta, Georgia, USA
| | - Terry Brissac
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Aimee R P Tierney
- Graduate Program in Microbiology and Molecular Genetics, Emory University, Atlanta, Georgia, USA
| | - Kurt Warncke
- Department of Physics, Emory University, Atlanta, Georgia, USA
| | - Carlos J Orihuela
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Timothy D Read
- Graduate Program in Microbiology and Molecular Genetics, Emory University, Atlanta, Georgia, USA
- Antibiotic Research Center, Emory University, Atlanta, Georgia, USA
- School of Medicine, Emory University, Atlanta, Georgia, USA
| | - Jorge E Vidal
- Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
- Graduate Program in Microbiology and Molecular Genetics, Emory University, Atlanta, Georgia, USA
- Antibiotic Research Center, Emory University, Atlanta, Georgia, USA
| |
Collapse
|
33
|
Gao Y, Xu W, Dou X, Wang H, Zhang X, Yang S, Liao H, Hu X, Wang H. Mitochondrial DNA Leakage Caused by Streptococcus pneumoniae Hydrogen Peroxide Promotes Type I IFN Expression in Lung Cells. Front Microbiol 2019; 10:630. [PMID: 30984149 PMCID: PMC6447684 DOI: 10.3389/fmicb.2019.00630] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Accepted: 03/13/2019] [Indexed: 12/17/2022] Open
Abstract
Streptococcus pneumoniae (S. pn), the bacterial pathogen responsible for invasive pneumococcal diseases, is capable of producing substantial amounts of hydrogen peroxide. However, the impact of S. pn-secreted hydrogen peroxide (H2O2) on the host immune processes is not completely understood. Here, we demonstrated that S. pn-secreted H2O2 caused mitochondrial damage and severe histopathological damage in mouse lung tissue. Additionally, S. pn-secreted H2O2 caused not only oxidative damage to mitochondrial deoxyribonucleic acid (mtDNA), but also a reduction in the mtDNA content in alveolar epithelia cells. This resulted in the release of mtDNA into the cytoplasm, which subsequently induced type I interferons (IFN-I) expression. We also determined that stimulator of interferon genes (STING) signaling was probably involved in S. pn H2O2-inducing IFN-I expression in response to mtDNA damaged by S. pn-secreted H2O2. In conclusion, our study demonstrated that H2O2 produced by S. pn resulted in mtDNA leakage from damaged mitochondria and IFN-I production in alveolar epithelia cells, and STING may be required in this process, and this is a novel mitochondrial damage mechanism by which S. pn potentiates the IFN-I cascade in S. pn infection.
Collapse
Affiliation(s)
- Yue Gao
- Key Laboratory of Diagnostic Medicine Designated by the Ministry of Education, Chongqing Medical University, Chongqing, China.,School of Laboratory Medicine, Chongqing Medical University, Chongqing, China
| | - Wenchun Xu
- Key Laboratory of Diagnostic Medicine Designated by the Ministry of Education, Chongqing Medical University, Chongqing, China.,School of Laboratory Medicine, Chongqing Medical University, Chongqing, China
| | - Xiaoyun Dou
- Institute of Life Sciences, Chongqing Medical University, Chongqing, China
| | - Hong Wang
- Institute of Life Sciences, Chongqing Medical University, Chongqing, China
| | - Xuemei Zhang
- Key Laboratory of Diagnostic Medicine Designated by the Ministry of Education, Chongqing Medical University, Chongqing, China.,School of Laboratory Medicine, Chongqing Medical University, Chongqing, China
| | - Shenghui Yang
- Key Laboratory of Diagnostic Medicine Designated by the Ministry of Education, Chongqing Medical University, Chongqing, China.,School of Laboratory Medicine, Chongqing Medical University, Chongqing, China
| | - Hongyi Liao
- Key Laboratory of Diagnostic Medicine Designated by the Ministry of Education, Chongqing Medical University, Chongqing, China.,School of Laboratory Medicine, Chongqing Medical University, Chongqing, China
| | - Xuexue Hu
- Key Laboratory of Diagnostic Medicine Designated by the Ministry of Education, Chongqing Medical University, Chongqing, China.,School of Laboratory Medicine, Chongqing Medical University, Chongqing, China
| | - Hong Wang
- Key Laboratory of Diagnostic Medicine Designated by the Ministry of Education, Chongqing Medical University, Chongqing, China.,School of Laboratory Medicine, Chongqing Medical University, Chongqing, China
| |
Collapse
|
34
|
Xia X, Qin W, Zhu H, Wang X, Jiang J, Hu J. How Streptococcus suis serotype 2 attempts to avoid attack by host immune defenses. JOURNAL OF MICROBIOLOGY, IMMUNOLOGY, AND INFECTION = WEI MIAN YU GAN RAN ZA ZHI 2019; 52:516-525. [PMID: 30954397 DOI: 10.1016/j.jmii.2019.03.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2018] [Revised: 02/20/2019] [Accepted: 03/07/2019] [Indexed: 01/08/2023]
Abstract
Streptococcus suis (S. suis) type 2 (SS2) is an important zoonotic pathogen that causes swine streptococcosis, a widespread infectious disease that occurs in pig production areas worldwide and causes serious economic losses in the pork industry. Hosts recognize pathogen-associated molecular patterns (PAMPs) through pattern recognition receptors (PRRs) to activate both innate and acquired immune responses. However, S. suis has evolved multiple mechanisms to escape host defenses. Pathogenic proteins, such as enolase, double-component regulatory systems, factor H-combining proteins and other pathogenic and virulence factors, contribute to immune escape by evading host phagocytosis, reactive oxygen species (ROS), complement-mediated immune destruction, etc. SS2 can prevent neutrophil extracellular trap (NET) formation to avoid being trapped by porcine neutrophils and disintegrate host immunoglobulins via IgA1 hydrolases and IgM proteases. Currently, the pathogenesis of arthritis and meningitis caused by SS2 infection remains unclear, and further studies are necessary to elucidate it. Understanding immune evasion mechanisms after SS2 infection is important for developing high-efficiency vaccines and targeted drugs.
Collapse
Affiliation(s)
- Xiaojing Xia
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, China; Postdoctoral Research Base, Henan Institute of Science and Technology, Xinxiang, China; Postdoctoral Research Station, Henan Agriculture University, Zhengzhou, China
| | - Wanhai Qin
- Amsterdam UMC, University of Amsterdam, Center for Experimental and Molecular Medicine, Amsterdam Infection & Immunity, Meibergdreef 9, 1105AZ Amsterdam, Netherlands
| | - Huili Zhu
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, China
| | - Xin Wang
- College of Agriculture and Forestry Science, Linyi University, Linyi, China
| | - Jinqing Jiang
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, China.
| | - Jianhe Hu
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, China; Postdoctoral Research Base, Henan Institute of Science and Technology, Xinxiang, China.
| |
Collapse
|
35
|
Cools F, Torfs E, Aizawa J, Vanhoutte B, Maes L, Caljon G, Delputte P, Cappoen D, Cos P. Optimization and Characterization of a Galleria mellonella Larval Infection Model for Virulence Studies and the Evaluation of Therapeutics Against Streptococcus pneumoniae. Front Microbiol 2019; 10:311. [PMID: 30846978 PMCID: PMC6394149 DOI: 10.3389/fmicb.2019.00311] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 02/05/2019] [Indexed: 12/13/2022] Open
Abstract
Streptococcus pneumoniae is the leading cause of bacterial pneumonia. Infection is linked to high morbidity and mortality rates and antibiotic resistance within this pathogen is on the rise. Therefore, there is a need for novel antimicrobial therapies. To lower the time and costs of the drug discovery process, alternative in vivo models should be considered. As such, Galleria mellonella larvae can be of great value. The larval immunity consisting of several types of haemocytes is remarkably similar to the human innate immune system. Furthermore, these larvae don’t require specific housing, are cheap and are easy to handle. In this study, the use of a G. mellonella infection model to study early pneumococcal infections and treatment is proposed. Firstly, the fitness of this model to study pneumococcal virulence factors is confirmed using streptococcal strains TIGR4, ATCC®49619, D39 and its capsule-deficient counterpart R6 at different inoculum sizes. The streptococcal polysaccharide capsule is considered the most important virulence factor without which streptococci are unable to sustain an in vivo infection. Kaplan–Meier survival curves showed indeed a higher larval survival after infection with streptococcal strain R6 compared to strain D39. Then, the infection was characterized by determining the number of haemocytes, production of oxygen free radicals and bacterial burden at several time points during the course of infection. Lastly, treatment of infected larvae with the standard antibiotics amoxicillin and moxifloxacin was evaluated. Treatment has proven to have a positive outcome on the course of infection, depending on the administered dosage. These data imply that G. mellonella larvae can be used to evaluate antimicrobial therapies against S. pneumoniae, apart from using the larval model to study streptococcal properties. The in-depth knowledge acquired regarding this model, makes it more suitable for use in future research.
Collapse
Affiliation(s)
- Freya Cools
- Laboratory of Microbiology, Parasitology and Hygiene, Department of Pharmaceutical Sciences, University of Antwerp, Wilrijk, Belgium
| | - Eveline Torfs
- Laboratory of Microbiology, Parasitology and Hygiene, Department of Pharmaceutical Sciences, University of Antwerp, Wilrijk, Belgium
| | - Juliana Aizawa
- Laboratory of Microbiology, Parasitology and Hygiene, Department of Pharmaceutical Sciences, University of Antwerp, Wilrijk, Belgium
| | - Bieke Vanhoutte
- Laboratory of Microbiology, Parasitology and Hygiene, Department of Pharmaceutical Sciences, University of Antwerp, Wilrijk, Belgium
| | - Louis Maes
- Laboratory of Microbiology, Parasitology and Hygiene, Department of Pharmaceutical Sciences, University of Antwerp, Wilrijk, Belgium
| | - Guy Caljon
- Laboratory of Microbiology, Parasitology and Hygiene, Department of Pharmaceutical Sciences, University of Antwerp, Wilrijk, Belgium
| | - Peter Delputte
- Laboratory of Microbiology, Parasitology and Hygiene, Department of Pharmaceutical Sciences, University of Antwerp, Wilrijk, Belgium
| | - Davie Cappoen
- Laboratory of Microbiology, Parasitology and Hygiene, Department of Pharmaceutical Sciences, University of Antwerp, Wilrijk, Belgium
| | - Paul Cos
- Laboratory of Microbiology, Parasitology and Hygiene, Department of Pharmaceutical Sciences, University of Antwerp, Wilrijk, Belgium
| |
Collapse
|
36
|
Mendis N, Trigui H, Saad M, Tsang A, Faucher SP. Deletion of oxyR in Legionella pneumophila causes growth defect on agar. Can J Microbiol 2018; 64:1030-1041. [PMID: 30212639 DOI: 10.1139/cjm-2018-0129] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The intracellular pathogen Legionella pneumophila (Lp) is a strict aerobe, surviving and replicating in environments where it frequently encounters reactive oxygen species (ROS), such as the nutrient-poor water environment and its replicative niche inside host cells. In many proteobacteria, the LysR-type regulator OxyR controls the oxidative stress response; however, the importance of the OxyR homologue in Lp is still unclear. Therefore, we undertook the characterization of phenotypes associated with the deletion of oxyR in Lp. Contrary to the wild type, the oxyR deletion mutant exhibits a severe growth defect on charcoal - yeast extract (CYE) agar lacking α-ketoglutarate supplementation. Growth in AYE broth (CYE without agar and charcoal), in amoeba and in human cultured macrophages, and survival in water is unaffected by the deletion. Supplementing CYE agar with antioxidants that neutralize ROS or introducing the oxyR gene in trans rescues the observed growth defect. Moreover, the mutant grows as well as the wild type on CYE plates made with agarose instead of agar, suggesting that a compound present in the latter is responsible for the growth defect phenotype.
Collapse
Affiliation(s)
- Nilmini Mendis
- Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, QC H9X 3V9, Canada.,Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, QC H9X 3V9, Canada
| | - Hana Trigui
- Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, QC H9X 3V9, Canada.,Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, QC H9X 3V9, Canada
| | - Mariam Saad
- Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, QC H9X 3V9, Canada.,Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, QC H9X 3V9, Canada
| | - Adrianna Tsang
- Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, QC H9X 3V9, Canada.,Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, QC H9X 3V9, Canada
| | - Sébastien P Faucher
- Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, QC H9X 3V9, Canada.,Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, QC H9X 3V9, Canada
| |
Collapse
|
37
|
Bartual SG, Alcorlo M, Martínez-Caballero S, Molina R, Hermoso JA. Three-dimensional structures of Lipoproteins from Streptococcus pneumoniae and Staphylococcus aureus. Int J Med Microbiol 2018; 308:692-704. [DOI: 10.1016/j.ijmm.2017.10.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 10/21/2017] [Indexed: 01/01/2023] Open
|
38
|
Streptococcus pneumoniae two-component regulatory systems: The interplay of the pneumococcus with its environment. Int J Med Microbiol 2018; 308:722-737. [DOI: 10.1016/j.ijmm.2017.11.012] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 11/21/2017] [Accepted: 11/24/2017] [Indexed: 02/06/2023] Open
|
39
|
Redanz S, Cheng X, Giacaman RA, Pfeifer CS, Merritt J, Kreth J. Live and let die: Hydrogen peroxide production by the commensal flora and its role in maintaining a symbiotic microbiome. Mol Oral Microbiol 2018; 33:337-352. [PMID: 29897662 DOI: 10.1111/omi.12231] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/11/2018] [Indexed: 02/05/2023]
Abstract
The majority of commensal oral streptococci are able to generate hydrogen peroxide (H2 O2 ) during aerobic growth, which can diffuse through the cell membrane and inhibit competing species in close proximity. Competing H2 O2 production is mainly dependent upon the pyruvate oxidase SpxB, and to a lesser extent the lactate oxidase LctO, both of which are important for energy generation in aerobic environments. Several studies point to a broad impact of H2 O2 production in the oral environment, including a potential role in biofilm homeostasis, signaling, and interspecies interactions. Here, we summarize the current research regarding oral streptococcal H2 O2 generation, resistance mechanisms, and the ecological impact of H2 O2 production. We also discuss the potential therapeutic utility of H2 O2 for the prevention/treatment of dysbiotic diseases as well as its potential role as a biomarker of oral health.
Collapse
Affiliation(s)
- Sylvio Redanz
- Department of Restorative Dentistry, Oregon Health and Science University, Portland, Oregon
| | - Xingqun Cheng
- The State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.,The Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Rodrigo A Giacaman
- Cariology Unit, Department of Oral Rehabilitation and Interdisciplinary Excellence Research Program on Healthy Aging (PIEI-ES), University of Talca, Talca, Chile
| | - Carmen S Pfeifer
- Department of Restorative Dentistry, Oregon Health and Science University, Portland, Oregon
| | - Justin Merritt
- Department of Restorative Dentistry, Oregon Health and Science University, Portland, Oregon
| | - Jens Kreth
- Department of Restorative Dentistry, Oregon Health and Science University, Portland, Oregon
| |
Collapse
|
40
|
Bayraç AT, Donmez SI. Selection of DNA aptamers to Streptococcus pneumonia and fabrication of graphene oxide based fluorescent assay. Anal Biochem 2018; 556:91-98. [PMID: 29964028 DOI: 10.1016/j.ab.2018.06.024] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 06/23/2018] [Accepted: 06/25/2018] [Indexed: 10/28/2022]
Abstract
Pneumococci are one of the leading causes of infections throughout the world causing problems mainly in children, elderly, and immune-deficient patients. In recent years antibiotic resistant Streptococcus pneumoniae strains become widespread. Therefore simple, rapid, and specific detection methods are needed for public health. In this study, DNA aptamer probes against S. pneumoniae were selected using bacterial Systematic Evolution of Ligands by Exponential Enrichment (SELEX) and these probes were integrated in to a graphene oxide (GO) based fluorescent assay. Among the tested aptamers three candidates Lyd-1, Lyd-2 and Lyd-3 showed Kd values of 844.7 ± 123.6, 1984.8 ± 347.5, and 661.8 ± 111.3 nM, respectively. These candidates showed binding affinity to S. pneumoniae and no specific binding to the bacteria used in negative selection. The binding of aptamers were showed by fluorescence spectroscopy and flow cytometry. GO based label-free fluorescent assay developed using Lyd-3 aptamer had a unique detection limit of 15 cfu mL-1. Thus we believe that the selected aptamers and fabricated GO based assay has potential to be used in the detection of S. pneumoniae. Selected aptamers selectively bind to S. pneumonia with anti-pneumococcal potential and holds great potential to be used as molecular probes for identifying and targeting.
Collapse
Affiliation(s)
- Abdullah Tahir Bayraç
- Department of Bioengineering, Karamanoglu Mehmetbey University, Yunus Emre Campus, 70100 Karaman, Turkey.
| | - Sultan Ilayda Donmez
- Department of Bioengineering, Karamanoglu Mehmetbey University, Yunus Emre Campus, 70100 Karaman, Turkey
| |
Collapse
|
41
|
Brooks LRK, Mias GI. Streptococcus pneumoniae's Virulence and Host Immunity: Aging, Diagnostics, and Prevention. Front Immunol 2018; 9:1366. [PMID: 29988379 PMCID: PMC6023974 DOI: 10.3389/fimmu.2018.01366] [Citation(s) in RCA: 124] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 06/01/2018] [Indexed: 12/14/2022] Open
Abstract
Streptococcus pneumoniae is an infectious pathogen responsible for millions of deaths worldwide. Diseases caused by this bacterium are classified as pneumococcal diseases. This pathogen colonizes the nasopharynx of its host asymptomatically, but overtime can migrate to sterile tissues and organs and cause infections. Pneumonia is currently the most common pneumococcal disease. Pneumococcal pneumonia is a global health concern and vastly affects children under the age of five as well as the elderly and individuals with pre-existing health conditions. S. pneumoniae has a large selection of virulence factors that promote adherence, invasion of host tissues, and allows it to escape host immune defenses. A clear understanding of S. pneumoniae's virulence factors, host immune responses, and examining the current techniques available for diagnosis, treatment, and disease prevention will allow for better regulation of the pathogen and its diseases. In terms of disease prevention, other considerations must include the effects of age on responses to vaccines and vaccine efficacy. Ongoing work aims to improve on current vaccination paradigms by including the use of serotype-independent vaccines, such as protein and whole cell vaccines. Extending our knowledge of the biology of, and associated host immune response to S. pneumoniae is paramount for our improvement of pneumococcal disease diagnosis, treatment, and improvement of patient outlook.
Collapse
Affiliation(s)
- Lavida R. K. Brooks
- Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, United States
- Institute for Quantitative Health Science & Engineering, Michigan State University, East Lansing, MI, United States
| | - George I. Mias
- Institute for Quantitative Health Science & Engineering, Michigan State University, East Lansing, MI, United States
- Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, United States
| |
Collapse
|
42
|
A Capsular Polysaccharide-Specific Antibody Alters Streptococcus pneumoniae Gene Expression during Nasopharyngeal Colonization of Mice. Infect Immun 2018; 86:IAI.00300-18. [PMID: 29735523 DOI: 10.1128/iai.00300-18] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 04/30/2018] [Indexed: 01/13/2023] Open
Abstract
Pneumococcal conjugate vaccines (PCV) elicit opsonophagocytic (opsonic) antibodies to pneumococcal capsular polysaccharides (PPS) and reduce nasopharyngeal (NP) colonization by vaccine-included Streptococcus pneumoniae serotypes. However, nonopsonic antibodies may also be important for protection against pneumococcal disease. For example, 1E2, a mouse IgG1 monoclonal antibody (MAb) to the serotype 3 (ST3) PPS (PPS3), reduced ST3 NP colonization in mice and altered ST3 gene expression in vitro Here, we determined whether 1E2 affects ST3 gene expression in vivo during colonization of mice by performing RNA sequencing on NP lavage fluid from ST3-infected mice treated with 1E2, a control MAb, or phosphate-buffered saline. Compared to the results for the controls, 1E2 significantly altered the expression of over 50 genes. It increased the expression of the piuBCDA operon, which encodes an iron uptake system, and decreased the expression of dpr, which encodes a protein critical for resistance to oxidative stress. 1E2-mediated effects on ST3 in vivo required divalent binding, as Fab fragments did not reduce NP colonization or alter ST3 gene expression. In vitro, 1E2 induced dose-dependent ST3 growth arrest and altered piuB and dpr expression, whereas an opsonic PPS3 MAb, 5F6, did not. 1E2-treated bacteria were more sensitive to hydrogen peroxide and the iron-requiring antibiotic streptonigrin, suggesting that 1E2 may increase iron import and enhance sensitivity to oxidative stress. Finally, 1E2 also induced rapid capsule shedding in vitro, suggesting that this may initiate 1E2-induced changes in sensitivity to oxidative stress and gene expression. Our data reveal a novel mechanism of direct, antibody-mediated antibacterial activity that could inform new directions in antipneumococcal therapy and vaccine development.
Collapse
|
43
|
Glanville DG, Han L, Maule AF, Woodacre A, Thanki D, Abdullah IT, Morrissey JA, Clarke TB, Yesilkaya H, Silvaggi NR, Ulijasz AT. RitR is an archetype for a novel family of redox sensors in the streptococci that has evolved from two-component response regulators and is required for pneumococcal colonization. PLoS Pathog 2018; 14:e1007052. [PMID: 29750817 PMCID: PMC5965902 DOI: 10.1371/journal.ppat.1007052] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Revised: 05/23/2018] [Accepted: 04/23/2018] [Indexed: 01/07/2023] Open
Abstract
To survive diverse host environments, the human pathogen Streptococcus pneumoniae must prevent its self-produced, extremely high levels of peroxide from reacting with intracellular iron. However, the regulatory mechanism(s) by which the pneumococcus accomplishes this balance remains largely enigmatic, as this pathogen and other related streptococci lack all known redox-sensing transcription factors. Here we describe a two-component-derived response regulator, RitR, as the archetype for a novel family of redox sensors in a subset of streptococcal species. We show that RitR works to both repress iron transport and enable nasopharyngeal colonization through a mechanism that exploits a single cysteine (Cys128) redox switch located within its linker domain. Biochemical experiments and phylogenetics reveal that RitR has diverged from the canonical two-component virulence regulator CovR to instead dimerize and bind DNA only upon Cys128 oxidation in air-rich environments. Atomic structures show that Cys128 oxidation initiates a "helical unravelling" of the RitR linker region, suggesting a mechanism by which the DNA-binding domain is then released to interact with its cognate regulatory DNA. Expanded computational studies indicate this mechanism could be shared by many microbial species outside the streptococcus genus.
Collapse
Affiliation(s)
- David G. Glanville
- Department of Microbiology and Immunology, Loyola University Chicago; Maywood, IL, United States of America
- MRC Centre for Molecular Bacteriology and Infection (CMBI), Imperial College London, London, United Kingdom
| | - Lanlan Han
- Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, United States of America
| | - Andrew F. Maule
- Department of Horticulture, University of Wisconsin–Madison, Linden Drive, Madison, Wisconsin, United States of America
| | - Alexandra Woodacre
- Department of Genetics, University of Leicester, Leicester, United Kingdom
| | - Devsaagar Thanki
- Department of Genetics, University of Leicester, Leicester, United Kingdom
| | - Iman Tajer Abdullah
- Department of Infection and Immunity, University of Leicester, Leicester, United Kingdom
| | - Julie A. Morrissey
- Department of Genetics, University of Leicester, Leicester, United Kingdom
| | - Thomas B. Clarke
- MRC Centre for Molecular Bacteriology and Infection (CMBI), Imperial College London, London, United Kingdom
| | - Hasan Yesilkaya
- Department of Infection and Immunity, University of Leicester, Leicester, United Kingdom
| | - Nicholas R. Silvaggi
- Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, United States of America
| | - Andrew T. Ulijasz
- Department of Microbiology and Immunology, Loyola University Chicago; Maywood, IL, United States of America
- MRC Centre for Molecular Bacteriology and Infection (CMBI), Imperial College London, London, United Kingdom
- * E-mail:
| |
Collapse
|
44
|
Zhi X, Abdullah IT, Gazioglu O, Manzoor I, Shafeeq S, Kuipers OP, Hiller NL, Andrew PW, Yesilkaya H. Rgg-Shp regulators are important for pneumococcal colonization and invasion through their effect on mannose utilization and capsule synthesis. Sci Rep 2018; 8:6369. [PMID: 29686372 PMCID: PMC5913232 DOI: 10.1038/s41598-018-24910-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 04/05/2018] [Indexed: 01/18/2023] Open
Abstract
Microbes communicate with each other by using quorum sensing (QS) systems and modulate their collective 'behavior' for in-host colonization and virulence, biofilm formation, and environmental adaptation. The recent increase in genome data availability reveals the presence of several putative QS sensing circuits in microbial pathogens, but many of these have not been functionally characterized yet, despite their possible utility as drug targets. To increase the repertoire of functionally characterized QS systems in bacteria, we studied Rgg144/Shp144 and Rgg939/Shp939, two putative QS systems in the important human pathogen Streptococcus pneumoniae. We find that both of these QS circuits are induced by short hydrophobic peptides (Shp) upon sensing sugars found in the respiratory tract, such as galactose and mannose. Microarray analyses using cultures grown on mannose and galactose revealed that the expression of a large number of genes is controlled by these QS systems, especially those encoding for essential physiological functions and virulence-related genes such as the capsular locus. Moreover, the array data revealed evidence for cross-talk between these systems. Finally, these Rgg systems play a key role in colonization and virulence, as deletion mutants of these QS systems are attenuated in the mouse models of colonization and pneumonia.
Collapse
Affiliation(s)
- Xiangyun Zhi
- Department of Infection, Immunity & Inflammation, University of Leicester, Leicester, LE1 9HN, UK
| | - Iman Tajer Abdullah
- Department of Infection, Immunity & Inflammation, University of Leicester, Leicester, LE1 9HN, UK
- Department of Biology, College of Science, University of Kirkuk, Kirkuk, Iraq
| | - Ozcan Gazioglu
- Department of Infection, Immunity & Inflammation, University of Leicester, Leicester, LE1 9HN, UK
| | - Irfan Manzoor
- Molecular Genetics, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands
| | - Sulman Shafeeq
- Molecular Genetics, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands
| | - Oscar P Kuipers
- Molecular Genetics, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands
| | - N Luisa Hiller
- Department of Biological Sciences, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA, 15213, USA
| | - Peter W Andrew
- Department of Infection, Immunity & Inflammation, University of Leicester, Leicester, LE1 9HN, UK
| | - Hasan Yesilkaya
- Department of Infection, Immunity & Inflammation, University of Leicester, Leicester, LE1 9HN, UK.
| |
Collapse
|
45
|
Macrophage Polarization Alters Postphagocytosis Survivability of the Commensal Streptococcus gordonii. Infect Immun 2018; 86:IAI.00858-17. [PMID: 29229734 DOI: 10.1128/iai.00858-17] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 12/05/2017] [Indexed: 12/22/2022] Open
Abstract
Oral streptococci are generally considered commensal organisms; however, they are becoming recognized as important associate pathogens during the development of periodontal disease as well as being associated with several systemic diseases, including as a causative agent of infective endocarditis. An important virulence determinant of these bacteria is an ability to evade destruction by phagocytic cells, yet how this subversion occurs is mostly unknown. Using Streptococcus gordonii as a model commensal oral streptococcus that is also associated with disease, we find that resistance to reactive oxygen species (ROS) with an active ability to damage phagosomes allows the bacterium to avoid destruction within macrophages. This ability to survive relies not only on the ROS resistance capabilities of the bacterium but also on ROS production by macrophages, with both being required for maximal survival of internalized bacteria. Importantly, we also show that this dependence on ROS production by macrophages for resistance has functional significance: S. gordonii intracellular survival increases when macrophages are polarized toward an activated (M1) profile, which is known to result in prolonged phagosomal ROS production compared to that of alternatively (M2) polarized macrophages. We additionally find evidence of the bacterium being capable of both delaying the maturation of and damaging phagosomes. Taken together, these results provide essential insights regarding the mechanisms through which normally commensal oral bacteria can contribute to both local and systemic inflammatory disease.
Collapse
|
46
|
Lewis ML, Surewaard BGJ. Neutrophil evasion strategies by Streptococcus pneumoniae and Staphylococcus aureus. Cell Tissue Res 2017; 371:489-503. [PMID: 29204747 DOI: 10.1007/s00441-017-2737-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 11/06/2017] [Indexed: 02/05/2023]
Abstract
Humans are well equipped to defend themselves against bacteria. The innate immune system employs diverse mechanisms to recognize, control and initiate a response that can destroy millions of different microbes. Microbes that evade the sophisticated innate immune system are able to escape detection and could become pathogens. The pathogens Streptococcus pneumoniae and Staphylococcus aureus are particularly successful due to the development of a wide variety of virulence strategies for bacterial pathogenesis and they invest significant efforts towards mechanisms that allow for neutrophil evasion. Neutrophils are a primary cellular defense and can rapidly kill invading microbes, which is an indispensable function for maintaining host health. This review compares the key features of Streptococcus pneumoniae and Staphylococcus aureus in epidemiology, with a specific focus on virulence mechanisms utilized to evade neutrophils in bacterial pathogenesis. It is important to understand the complex interactions between pathogenic bacteria and neutrophils so that we can disrupt the ability of pathogens to cause disease.
Collapse
Affiliation(s)
- Megan L Lewis
- Department of Physiology & Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
| | - Bas G J Surewaard
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB, Canada. .,Department of Medical Microbiology, University Medical Centre, Utrecht, Netherlands.
| |
Collapse
|
47
|
Staerck C, Gastebois A, Vandeputte P, Calenda A, Larcher G, Gillmann L, Papon N, Bouchara JP, Fleury MJ. Microbial antioxidant defense enzymes. Microb Pathog 2017. [DOI: 10.1016/j.micpath.2017.06.015] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
|
48
|
Turner AG, Ong CLY, Walker MJ, Djoko KY, McEwan AG. Transition Metal Homeostasis in Streptococcus pyogenes and Streptococcus pneumoniae. Adv Microb Physiol 2017; 70:123-191. [PMID: 28528647 DOI: 10.1016/bs.ampbs.2017.01.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Trace metals such as Fe, Mn, Zn and Cu are essential for various biological functions including proper innate immune function. The host immune system has complicated and coordinated mechanisms in place to either starve and/or overload invading pathogens with various metals to combat the infection. Here, we discuss the roles of Fe, Mn and Zn in terms of nutritional immunity, and also the roles of Cu and Zn in metal overload in relation to the physiology and pathogenesis of two human streptococcal species, Streptococcus pneumoniae and Streptococcus pyogenes. S. pneumoniae is a major human pathogen that is carried asymptomatically in the nasopharynx by up to 70% of the population; however, transition to internal sites can cause a range of diseases such as pneumonia, otitis media, meningitis and bacteraemia. S. pyogenes is a human pathogen responsible for diseases ranging from pharyngitis and impetigo, to severe invasive infections. Both species have overlapping capacity with respect to metal acquisition, export and regulation and how metal homeostasis relates to their virulence and ability to invade and survive within the host. It is becoming more apparent that metals have an important role to play in the control of infection, and with further investigations, it could lead to the potential use of metals in novel antimicrobial therapies.
Collapse
Affiliation(s)
- Andrew G Turner
- School of Chemistry and Molecular Biosciences and Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, QLD, Australia
| | - Cheryl-Lynn Y Ong
- School of Chemistry and Molecular Biosciences and Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, QLD, Australia
| | - Mark J Walker
- School of Chemistry and Molecular Biosciences and Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, QLD, Australia
| | - Karrera Y Djoko
- School of Chemistry and Molecular Biosciences and Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, QLD, Australia
| | - Alastair G McEwan
- School of Chemistry and Molecular Biosciences and Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, QLD, Australia.
| |
Collapse
|
49
|
Biological and Chemical Adaptation to Endogenous Hydrogen Peroxide Production in Streptococcus pneumoniae D39. mSphere 2017; 2:mSphere00291-16. [PMID: 28070562 PMCID: PMC5214746 DOI: 10.1128/msphere.00291-16] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 12/04/2016] [Indexed: 12/29/2022] Open
Abstract
Adaptation to endogenous oxidative stress is an integral aspect of Streptococcus pneumoniae colonization and virulence. In this work, we identify key transcriptomic and proteomic features of the pneumococcal endogenous oxidative stress response. The thiol peroxidase TpxD plays a critical role in adaptation to endogenous H2O2 and serves to limit protein sulfenylation of glycolytic, capsule, and nucleotide biosynthesis enzymes in S. pneumoniae. The catalase-negative, facultative anaerobe Streptococcus pneumoniae D39 is naturally resistant to hydrogen peroxide (H2O2) produced endogenously by pyruvate oxidase (SpxB). Here, we investigate the adaptive response to endogenously produced H2O2. We show that lactate oxidase, which converts lactate to pyruvate, positively impacts pyruvate flux through SpxB and that ΔlctO mutants produce significantly lower H2O2. In addition, both the SpxB pathway and a candidate pyruvate dehydrogenase complex (PDHC) pathway contribute to acetyl coenzyme A (acetyl-CoA) production during aerobic growth, and the pyruvate format lyase (PFL) pathway is the major acetyl-CoA pathway during anaerobic growth. Microarray analysis of the D39 strain cultured under aerobic versus strict anaerobic conditions shows upregulation of spxB, a gene encoding a rhodanese-like protein (locus tag spd0091), tpxD, sodA, piuB, piuD, and an Fe-S protein biogenesis operon under H2O2-producing conditions. Proteome profiling of H2O2-induced sulfenylation reveals that sulfenylation levels correlate with cellular H2O2 production, with endogenous sulfenylation of ≈50 proteins. Deletion of tpxD increases cellular sulfenylation 5-fold and has an inhibitory effect on ATP generation. Two major targets of protein sulfenylation are glyceraldehyde-3-phosphate dehydrogenase (GapA) and SpxB itself, but targets also include pyruvate kinase, LctO, AdhE, and acetate kinase (AckA). Sulfenylation of GapA is inhibitory, while the effect on SpxB activity is negligible. Strikingly, four enzymes of capsular polysaccharide biosynthesis are sulfenylated, as are enzymes associated with nucleotide biosynthesis via ribulose-5-phosphate. We propose that LctO/SpxB-generated H2O2 functions as a signaling molecule to downregulate capsule production and drive altered flux through sugar utilization pathways. IMPORTANCE Adaptation to endogenous oxidative stress is an integral aspect of Streptococcus pneumoniae colonization and virulence. In this work, we identify key transcriptomic and proteomic features of the pneumococcal endogenous oxidative stress response. The thiol peroxidase TpxD plays a critical role in adaptation to endogenous H2O2 and serves to limit protein sulfenylation of glycolytic, capsule, and nucleotide biosynthesis enzymes in S. pneumoniae.
Collapse
|
50
|
Devraj G, Beerlage C, Brüne B, Kempf VAJ. Hypoxia and HIF-1 activation in bacterial infections. Microbes Infect 2016; 19:144-156. [PMID: 27903434 DOI: 10.1016/j.micinf.2016.11.003] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 11/14/2016] [Accepted: 11/21/2016] [Indexed: 12/22/2022]
Abstract
For most of the living beings, oxygen is one of the essential elements required to sustain life. Deprivation of oxygen causes tissue hypoxia and this severely affects host cell and organ functions. Tissue hypoxia is a prominent microenvironmental condition occurring in infections and there is a body of evidence that hypoxia and inflammation are interconnected with each other. The primary key factor mediating the mammalian hypoxic response is hypoxia inducible factor (HIF)-1, which regulates oxygen homeostasis on cellular, tissue and organism level. Recent studies show that HIF-1 plays a central role in angiogenesis, cancer and cardiovascular disease but also in bacterial infections. Activation of HIF-1 depends on the nature of the pathogen and the characteristics of infections in certain hosts. Up to date, it is not completely clear whether the phenomenon of HIF-1 activation in infections has a protective or detrimental effect on the host. In this review, we give an overview of whether and how hypoxia and HIF-1 affect the course of infections.
Collapse
Affiliation(s)
- Gayatri Devraj
- Institute of Medical Microbiology and Infection Control, Goethe-University, Paul-Ehrlich-Str. 40, D-60596 Frankfurt am Main, Germany
| | - Christiane Beerlage
- Institute of Medical Microbiology and Infection Control, Goethe-University, Paul-Ehrlich-Str. 40, D-60596 Frankfurt am Main, Germany
| | - Bernhard Brüne
- Institute of Biochemistry I - Pathobiochemistry, Goethe-University, Theodor-Stern-Kai 7, D-60590 Frankfurt am Main, Germany
| | - Volkhard A J Kempf
- Institute of Medical Microbiology and Infection Control, Goethe-University, Paul-Ehrlich-Str. 40, D-60596 Frankfurt am Main, Germany.
| |
Collapse
|