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Gulati M, Thomas JM, Ennis CL, Hernday AD, Rawat M, Nobile CJ. The bacillithiol pathway is required for biofilm formation in Staphylococcus aureus. Microb Pathog 2024; 191:106657. [PMID: 38649100 DOI: 10.1016/j.micpath.2024.106657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 04/16/2024] [Accepted: 04/18/2024] [Indexed: 04/25/2024]
Abstract
Staphylococcus aureus is a major human pathogen that can cause infections that range from superficial skin and mucosal infections to life threatening disseminated infections. S. aureus can attach to medical devices and host tissues and form biofilms that allow the bacteria to evade the host immune system and provide protection from antimicrobial agents. To counter host-generated oxidative and nitrosative stress mechanisms that are part of the normal host responses to invading pathogens, S. aureus utilizes low molecular weight (LMW) thiols, such as bacillithiol (BSH). Additionally, S. aureus synthesizes its own nitric oxide (NO), which combined with its downstream metabolites may also protect the bacteria against specific host responses. We have previously shown that LMW thiols are required for biofilm formation in Mycobacterium smegmatis and Pseudomonas aeruginosa. Here, we show that the S. aureus bshC mutant strain, which is defective in the last step of the BSH pathway and lacks BSH, is impaired in biofilm formation. We also identify a possible S-nitrosobacillithiol reductase (BSNOR), similar in sequence to an S-nitrosomycothiol reductase found in M. smegmatis and show that the putative S. aureus bsnoR mutant strain has reduced levels of BSH and decreased biofilm formation. Our studies also show that NO plays an important role in biofilm formation and that acidified sodium nitrite severely reduces biofilm thickness. These studies provide insight into the roles of oxidative and nitrosative stress mechanisms on biofilm formation and indicate that BSH and NO are key players in normal biofilm formation in S. aureus.
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Affiliation(s)
- Megha Gulati
- Department of Molecular and Cell Biology, University of California Merced, Merced, CA, USA
| | - Jason M Thomas
- Department of Biology, California State University-Fresno, Fresno, CA, USA
| | - Craig L Ennis
- Department of Molecular and Cell Biology, University of California Merced, Merced, CA, USA; Quantitative and Systems Biology Graduate Program, University of California, Merced, CA, USA
| | - Aaron D Hernday
- Department of Molecular and Cell Biology, University of California Merced, Merced, CA, USA; Health Sciences Research Institute, University of California, Merced, CA, USA
| | - Mamta Rawat
- Department of Biology, California State University-Fresno, Fresno, CA, USA.
| | - Clarissa J Nobile
- Department of Molecular and Cell Biology, University of California Merced, Merced, CA, USA; Health Sciences Research Institute, University of California, Merced, CA, USA.
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2
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Hauserman MR, Ferraro MJ, Carroll RK, Rice KC. Altered quorum sensing and physiology of Staphylococcus aureus during spaceflight detected by multi-omics data analysis. NPJ Microgravity 2024; 10:2. [PMID: 38191486 PMCID: PMC10774393 DOI: 10.1038/s41526-023-00343-7] [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: 07/10/2023] [Accepted: 12/15/2023] [Indexed: 01/10/2024] Open
Abstract
Staphylococcus aureus colonizes the nares of approximately 30% of humans, a risk factor for opportunistic infections. To gain insight into S. aureus virulence potential in the spaceflight environment, we analyzed RNA-Seq, cellular proteomics, and metabolomics data from the "Biological Research in Canisters-23" (BRIC-23) GeneLab spaceflight experiment, a mission designed to measure the response of S. aureus to growth in low earth orbit on the international space station. This experiment used Biological Research in Canisters-Petri Dish Fixation Units (BRIC-PDFUs) to grow asynchronous ground control and spaceflight cultures of S. aureus for 48 h. RNAIII, the effector of the Accessory Gene Regulator (Agr) quorum sensing system, was the most highly upregulated gene transcript in spaceflight relative to ground controls. The agr operon gene transcripts were also highly upregulated during spaceflight, followed by genes encoding phenol-soluble modulins and secreted proteases, which are positively regulated by Agr. Upregulated spaceflight genes/proteins also had functions related to urease activity, type VII-like Ess secretion, and copper transport. We also performed secretome analysis of BRIC-23 culture supernatants, which revealed that spaceflight samples had increased abundance of secreted virulence factors, including Agr-regulated proteases (SspA, SspB), staphylococcal nuclease (Nuc), and EsxA (secreted by the Ess system). These data also indicated that S. aureus metabolism is altered in spaceflight conditions relative to the ground controls. Collectively, these data suggest that S. aureus experiences increased quorum sensing and altered expression of virulence factors in response to the spaceflight environment that may impact its pathogenic potential.
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Affiliation(s)
- Matthew R Hauserman
- Department of Microbiology and Cell Science, IFAS, University of Florida, Gainesville, FL, USA
| | - Mariola J Ferraro
- Department of Microbiology and Cell Science, IFAS, University of Florida, Gainesville, FL, USA
| | - Ronan K Carroll
- Department of Biological Sciences, Ohio University, Athens, OH, USA
| | - Kelly C Rice
- Department of Microbiology and Cell Science, IFAS, University of Florida, Gainesville, FL, USA.
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3
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Brandwein JN, Sculthorpe TS, Ridder MJ, Bose JL, Rice KC. Factors impacting the regulation of nos gene expression in Staphylococcus aureus. Microbiol Spectr 2023; 11:e0168823. [PMID: 37747881 PMCID: PMC10580903 DOI: 10.1128/spectrum.01688-23] [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: 04/25/2023] [Accepted: 07/29/2023] [Indexed: 09/27/2023] Open
Abstract
Staphylococcus aureus nitric oxide synthase (saNOS) contributes to oxidative stress resistance, antibiotic tolerance, virulence, and modulation of aerobic and nitrate-based cellular respiration. Despite its involvement in these essential processes, the genetic regulation of nos expression has not been well characterized. 5' rapid amplification of cDNA ends on nos RNA isolated from S. aureus UAMS-1 (USA200 strain) and AH1263 (USA300 strain) revealed that the nos transcriptional start site mapped to an adenine nucleotide in the predicted Shine-Dalgarno site located 11 bp upstream of the nos ATG start codon, suggesting that the nos transcript may have a leaderless organization or may be subject to processing. The SrrAB two-component system (TCS) was previously identified as a positive regulator of nos RNA levels, and experiments using a β-galactosidase reporter plasmid confirmed that SrrAB is a positive regulator of nos promoter activity. In addition, the quorum-sensing system Agr was identified as a negative regulator of low-oxygen nos expression in UAMS-1, with activity epistatic to SrrAB. Involvement of Agr was strain dependent, as nos expression remained unchanged in an AH1263 agr mutant, which has higher Agr activity compared to UAMS-1. Furthermore, nos promoter activity and RNA levels were significantly stronger in AH1263 relative to UAMS-1 during late-exponential low-oxygen growth, when nos expression is maximal. Global regulators Rex and MgrA were also implicated as negative regulators of low-oxygen nos promoter activity in UAMS-1. Collectively, these results provide new insight into factors that control nos expression.IMPORTANCEBacterial nitric oxide synthase (bNOS) has recently emerged in several species as a key player in resistance to stresses commonly encountered during infection. Although Staphylococcus aureus (sa)NOS has been suggested to be a promising drug target in S. aureus, an obstacle to this in practice is the existence of mammalian NOS, whose oxygenase domain is like bacterial NOS. Increased understanding of the nos regulatory network in S. aureus could allow targeting of saNOS through its regulators, bypassing the issue of also inhibiting mammalian NOS. Furthermore, the observed strain-dependent differences in S. aureus nos regulation presented in this study reinforce the importance of studying bacterial NOS regulation and function at both the strain and species levels.
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Affiliation(s)
- Jessica N. Brandwein
- Department of Microbiology & Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida, USA
| | - Tiffany S. Sculthorpe
- Department of Microbiology & Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida, USA
| | - Miranda J. Ridder
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Jeffrey L. Bose
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Kelly C. Rice
- Department of Microbiology & Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida, USA
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4
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Shu X, Shi Y, Huang Y, Yu D, Sun B. Transcription tuned by S-nitrosylation underlies a mechanism for Staphylococcus aureus to circumvent vancomycin killing. Nat Commun 2023; 14:2318. [PMID: 37085493 PMCID: PMC10120478 DOI: 10.1038/s41467-023-37949-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 04/06/2023] [Indexed: 04/23/2023] Open
Abstract
Treatment of Staphylococcus aureus infections is a constant challenge due to emerging resistance to vancomycin, a last-resort drug. S-nitrosylation, the covalent attachment of a nitric oxide (NO) group to a cysteine thiol, mediates redox-based signaling for eukaryotic cellular functions. However, its role in bacteria is largely unknown. Here, proteomic analysis revealed that S-nitrosylation is a prominent growth feature of vancomycin-intermediate S. aureus. Deletion of NO synthase (NOS) or removal of S-nitrosylation from the redox-sensitive regulator MgrA or WalR resulted in thinner cell walls and increased vancomycin susceptibility, which was due to attenuated promoter binding and released repression of genes involved in cell wall metabolism. These genes failed to respond to H2O2-induced oxidation, suggesting distinct transcriptional responses to alternative modifications of the cysteine residue. Furthermore, treatment with a NOS inhibitor significantly decreased vancomycin resistance in S. aureus. This study reveals that transcriptional regulation via S-nitrosylation underlies a mechanism for NO-mediated bacterial antibiotic resistance.
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Affiliation(s)
- Xueqin Shu
- Department of Oncology, The First Affiliated Hospital, University of Science and Technology of China, Hefei, China
- Department of Life Science and Medicine, University of Science and Technology of China, Hefei, China
| | - Yingying Shi
- Department of Oncology, The First Affiliated Hospital, University of Science and Technology of China, Hefei, China
- Department of Life Science and Medicine, University of Science and Technology of China, Hefei, China
| | - Yi Huang
- Department of Oncology, The First Affiliated Hospital, University of Science and Technology of China, Hefei, China
- Department of Life Science and Medicine, University of Science and Technology of China, Hefei, China
| | - Dan Yu
- Laboratory of Dermatology, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, Key Laboratory of Major Diseases in Children, Ministry of Education, National Center for Children's Health, Beijing, China.
| | - Baolin Sun
- Department of Oncology, The First Affiliated Hospital, University of Science and Technology of China, Hefei, China.
- Department of Life Science and Medicine, University of Science and Technology of China, Hefei, China.
- CAS Laboratory of Innate Immunity and Chronic Disease, University of Science and Technology of China, Hefei, China.
- Hefei National Laboratory for Physical Sciences at Microscale, Hefei, China.
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5
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Ruiz B, Sauviac L, Brouquisse R, Bruand C, Meilhoc E. Role of Nitric Oxide of Bacterial Origin in the Medicago truncatula-Sinorhizobium meliloti Symbiosis. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2022; 35:887-892. [PMID: 35762680 DOI: 10.1094/mpmi-05-22-0118-sc] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Nitric oxide (NO) is a small ubiquitous gaseous molecule that has been found in many host-pathogen interactions. NO has been shown to be part of the defense arsenal of animal cells and more recently of plant cells. To fight this molecular weapon, pathogens have evolved responses consisting of adaptation to NO or degradation of this toxic molecule. More recently, it was shown that NO could also be produced by the pathogen and contributes likewise to the success of the host cell infection. NO is also present during symbiotic interactions. Despite growing knowledge about the role of NO during friendly interactions, data on the specificity of action of NO produced by each partner are scarce, partly due to the multiplicity of NO production systems. In the nitrogen-fixing symbiosis between the soil bacterium Sinorhizobium meliloti and the model legume Medicago truncatula, NO has been detected at all steps of the interaction, where it displays various roles. Both partners contribute to NO production inside the legume root nodules where nitrogen fixation occurs. The study focuses on the role of bacterial NO in this interaction. We used a genetic approach to identify bacterial NO sources in the symbiotic context and to test the phenotype in planta of bacterial mutants affected in NO production. Our results show that only denitrification is a source of bacterial NO in Medicago nodules, giving insight into the role of bacteria-derived NO at different steps of the symbiotic interaction. [Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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Affiliation(s)
- Bryan Ruiz
- Laboratoire des Interactions Plantes-Microbes-Environnement (LIPME), Université de Toulouse, INRAE, CNRS, INSA, Castanet-Tolosan, France
| | - Laurent Sauviac
- Laboratoire des Interactions Plantes-Microbes-Environnement (LIPME), Université de Toulouse, INRAE, CNRS, INSA, Castanet-Tolosan, France
| | - Renaud Brouquisse
- Institut Sophia Agrobiotech (ISA), INRAE, CNRS, Université Côte d'Azur, 06903 Sophia Antipolis Cedex, France
| | - Claude Bruand
- Laboratoire des Interactions Plantes-Microbes-Environnement (LIPME), Université de Toulouse, INRAE, CNRS, INSA, Castanet-Tolosan, France
| | - Eliane Meilhoc
- Laboratoire des Interactions Plantes-Microbes-Environnement (LIPME), Université de Toulouse, INRAE, CNRS, INSA, Castanet-Tolosan, France
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6
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Gonçalves LG, Santos S, Gomes LP, Armengaud J, Miragaia M, Coelho AV. Skin-to-blood pH shift triggers metabolome and proteome global remodelling in Staphylococcus epidermidis. Front Microbiol 2022; 13:1000737. [PMID: 36246270 PMCID: PMC9554481 DOI: 10.3389/fmicb.2022.1000737] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 08/29/2022] [Indexed: 11/13/2022] Open
Abstract
Staphylococcus epidermidis is one of the most common bacteria of the human skin microbiota. Despite its role as a commensal, S. epidermidis has emerged as an opportunistic pathogen, associated with 80% of medical devices related infections. Moreover, these bacteria are extremely difficult to treat due to their ability to form biofilms and accumulate resistance to almost all classes of antimicrobials. Thus new preventive and therapeutic strategies are urgently needed. However, the molecular mechanisms associated with S. epidermidis colonisation and disease are still poorly understood. A deeper understanding of the metabolic and cellular processes associated with response to environmental factors characteristic of SE ecological niches in health and disease might provide new clues on colonisation and disease processes. Here we studied the impact of pH conditions, mimicking the skin pH (5.5) and blood pH (7.4), in a S. epidermidis commensal strain by means of next-generation proteomics and 1H NMR-based metabolomics. Moreover, we evaluated the metabolic changes occurring during a sudden pH change, simulating the skin barrier break produced by a catheter. We found that exposure of S. epidermidis to skin pH induced oxidative phosphorylation and biosynthesis of peptidoglycan, lipoteichoic acids and betaine. In contrast, at blood pH, the bacterial assimilation of monosaccharides and its oxidation by glycolysis and fermentation was promoted. Additionally, several proteins related to virulence and immune evasion, namely extracellular proteases and membrane iron transporters were more abundant at blood pH. In the situation of an abrupt skin-to-blood pH shift we observed the decrease in the osmolyte betaine and changes in the levels of several metabolites and proteins involved in cellular redoxl homeostasis. Our results suggest that at the skin pH S. epidermidis cells are metabolically more active and adhesion is promoted, while at blood pH, metabolism is tuned down and cells have a more virulent profile. pH increase during commensal-to-pathogen conversion appears to be a critical environmental signal to the remodelling of the S. epidermidis metabolism toward a more pathogenic state. Targeting S. epidermidis proteins induced by pH 7.4 and promoting the acidification of the medical device surface or surrounding environment might be new strategies to treat and prevent S. epidermidis infections.
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Affiliation(s)
- Luis Gafeira Gonçalves
- Laboratory of Proteomics of Non-Model Organisms, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Susana Santos
- Laboratory of Proteomics of Non-Model Organisms, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Laidson Paes Gomes
- Laboratory of Proteomics of Non-Model Organisms, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Jean Armengaud
- Département Médicaments et Technologies pour la Santé, SPI, Université Paris-Saclay, CEA, INRAE, Bagnols-sur-Cèze, France
| | - Maria Miragaia
- Laboratory of Bacterial Evolution and Molecular Epidemiology, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
- *Correspondence: Maria Miragaia,
| | - Ana Varela Coelho
- Laboratory of Proteomics of Non-Model Organisms, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
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7
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The Evolution of Nitric Oxide Function: From Reactivity in the Prebiotic Earth to Examples of Biological Roles and Therapeutic Applications. Antioxidants (Basel) 2022; 11:antiox11071222. [PMID: 35883712 PMCID: PMC9311577 DOI: 10.3390/antiox11071222] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 06/14/2022] [Accepted: 06/16/2022] [Indexed: 12/01/2022] Open
Abstract
Nitric oxide was once considered to be of marginal interest to the biological sciences and medicine; however, there is now wide recognition, but not yet a comprehensive understanding, of its functions and effects. NO is a reactive, toxic free radical with numerous biological targets, especially metal ions. However, NO and its reaction products also play key roles as reductant and oxidant in biological redox processes, in signal transduction, immunity and infection, as well as other roles. Consequently, it can be sensed, metabolized and modified in biological systems. Here, we present a brief overview of the chemistry and biology of NO—in particular, its origins in geological time and in contemporary biology, its toxic consequences and its critical biological functions. Given that NO, with its intrinsic reactivity, appeared in the early Earth’s atmosphere before the evolution of complex lifeforms, we speculate that the potential for toxicity preceded biological function. To examine this hypothesis, we consider the nature of non-biological and biological targets of NO, the evolution of biological mechanisms for NO detoxification, and how living organisms generate this multifunctional gas.
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The nuclear receptor ERR cooperates with the cardiogenic factor GATA4 to orchestrate cardiomyocyte maturation. Nat Commun 2022; 13:1991. [PMID: 35418170 PMCID: PMC9008061 DOI: 10.1038/s41467-022-29733-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 03/30/2022] [Indexed: 12/19/2022] Open
Abstract
Estrogen-related receptors (ERR) α and γ were shown recently to serve as regulators of cardiac maturation, yet the underlying mechanisms have not been delineated. Herein, we find that ERR signaling is necessary for induction of genes involved in mitochondrial and cardiac-specific contractile processes during human induced pluripotent stem cell-derived cardiomyocyte (hiPSC-CM) differentiation. Genomic interrogation studies demonstrate that ERRγ occupies many cardiomyocyte enhancers/super-enhancers, often co-localizing with the cardiogenic factor GATA4. ERRγ interacts with GATA4 to cooperatively activate transcription of targets involved in cardiomyocyte-specific processes such as contractile function, whereas ERRγ-mediated control of metabolic genes occurs independent of GATA4. Both mechanisms require the transcriptional coregulator PGC-1α. A disease-causing GATA4 mutation is shown to diminish PGC-1α/ERR/GATA4 cooperativity and expression of ERR target genes are downregulated in human heart failure samples suggesting that dysregulation of this circuitry may contribute to congenital and acquired forms of heart failure. Mature cardiac muscle requires high mitochondrial ATP production and specialized contractile proteins. Here the authors demonstrate that cardiomyocyte-specific contractile maturation involves cooperation between the nuclear receptor ERRγ and cardiogenic transcription factor GATA4, but ERRγ controls metabolic genes independently.
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9
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Defenses of multidrug resistant pathogens against reactive nitrogen species produced in infected hosts. Adv Microb Physiol 2022; 80:85-155. [PMID: 35489794 DOI: 10.1016/bs.ampbs.2022.02.001] [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] [Indexed: 01/27/2023]
Abstract
Bacterial pathogens have sophisticated systems that allow them to survive in hosts in which innate immunity is the frontline of defense. One of the substances produced by infected hosts is nitric oxide (NO) that together with its derived species leads to the so-called nitrosative stress, which has antimicrobial properties. In this review, we summarize the current knowledge on targets and protective systems that bacteria have to survive host-generated nitrosative stress. We focus on bacterial pathogens that pose serious health concerns due to the growing increase in resistance to currently available antimicrobials. We describe the role of nitrosative stress as a weapon for pathogen eradication, the detoxification enzymes, protein/DNA repair systems and metabolic strategies that contribute to limiting NO damage and ultimately allow survival of the pathogen in the host. Additionally, this systematization highlights the lack of available data for some of the most important human pathogens, a gap that urgently needs to be addressed.
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10
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Wang X, Li W, Wang W, Wang S, Xu T, Chen J, Zhang W. Involvement of Small Colony Variant-Related Heme Biosynthesis Genes in Staphylococcus aureus Persister Formation in vitro. Front Microbiol 2021; 12:756809. [PMID: 35003000 PMCID: PMC8733728 DOI: 10.3389/fmicb.2021.756809] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 11/24/2021] [Indexed: 11/17/2022] Open
Abstract
Background: Persisters are important reasons for persistent infections, and they can lead to antibiotic treatment failure in patients and consequently chronic infection. Staphylococcus aureus small colony variants (SCVs) have been shown to be related to persistent infection. Mutations in the genes of the heme biosynthesis pathway lead to the formation of SCVs. However, the relationship between heme production genes and persister has not been tested. Methods: HemA and hemB were knocked out by allelic replacement from S. aureus strain USA500 separately, and then, the heme deficiency was complemented by overexpression of related genes and the addition of hemin. The stress-related persister assay was conducted. RNA-sequencing was performed to find genes and pathways involved in heme-related persister formation, and relative genes and operons were further knocked out and overexpressed to confirm their role in each process. Results: We found that heme biosynthesis deficiency can lead to decreased persister. After complementing the corresponding genes or hemin, the persister levels could be restored. RNA-seq on knockout strains showed that various metabolic pathways were influenced, such as energy metabolism, amino acid metabolism, carbohydrate metabolism, and membrane transport. Overexpression of epiF and operon asp23 could restore USA500∆hemA persister formation under acid stress. Knocking out operon arc in USA500∆hemA could further reduce USA500∆hemA persister formation under acid and oxidative stress. Conclusion: Heme synthesis has a role in S. aureus persister formation.
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Affiliation(s)
- Xuyang Wang
- Department of Infectious Diseases, National Medical Center for Infectious Diseases, Shanghai Key Laboratory of Infectious Diseases and Biosafety Emergency Response, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Weizheng Li
- Department of Infectious Diseases, Putuo Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Wenjie Wang
- Department of Infectious Diseases, National Medical Center for Infectious Diseases, Shanghai Key Laboratory of Infectious Diseases and Biosafety Emergency Response, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Shiyong Wang
- Department of Infectious Diseases, National Medical Center for Infectious Diseases, Shanghai Key Laboratory of Infectious Diseases and Biosafety Emergency Response, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Tao Xu
- Department of Infectious Diseases, National Medical Center for Infectious Diseases, Shanghai Key Laboratory of Infectious Diseases and Biosafety Emergency Response, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Jiazhen Chen
- Department of Infectious Diseases, National Medical Center for Infectious Diseases, Shanghai Key Laboratory of Infectious Diseases and Biosafety Emergency Response, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Wenhong Zhang
- Department of Infectious Diseases, National Medical Center for Infectious Diseases, Shanghai Key Laboratory of Infectious Diseases and Biosafety Emergency Response, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
- National Clinical Research Center for Aging and Medicine, Huashan Hospital, Fudan University, Shanghai, China
- Key Laboratory of Medical Molecular Virology (MOE/MOH) Shanghai Medical College, Fudan University, Shanghai, China
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11
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Lehnert N, Kim E, Dong HT, Harland JB, Hunt AP, Manickas EC, Oakley KM, Pham J, Reed GC, Alfaro VS. The Biologically Relevant Coordination Chemistry of Iron and Nitric Oxide: Electronic Structure and Reactivity. Chem Rev 2021; 121:14682-14905. [PMID: 34902255 DOI: 10.1021/acs.chemrev.1c00253] [Citation(s) in RCA: 96] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Nitric oxide (NO) is an important signaling molecule that is involved in a wide range of physiological and pathological events in biology. Metal coordination chemistry, especially with iron, is at the heart of many biological transformations involving NO. A series of heme proteins, nitric oxide synthases (NOS), soluble guanylate cyclase (sGC), and nitrophorins, are responsible for the biosynthesis, sensing, and transport of NO. Alternatively, NO can be generated from nitrite by heme- and copper-containing nitrite reductases (NIRs). The NO-bearing small molecules such as nitrosothiols and dinitrosyl iron complexes (DNICs) can serve as an alternative vehicle for NO storage and transport. Once NO is formed, the rich reaction chemistry of NO leads to a wide variety of biological activities including reduction of NO by heme or non-heme iron-containing NO reductases and protein post-translational modifications by DNICs. Much of our understanding of the reactivity of metal sites in biology with NO and the mechanisms of these transformations has come from the elucidation of the geometric and electronic structures and chemical reactivity of synthetic model systems, in synergy with biochemical and biophysical studies on the relevant proteins themselves. This review focuses on recent advancements from studies on proteins and model complexes that not only have improved our understanding of the biological roles of NO but also have provided foundations for biomedical research and for bio-inspired catalyst design in energy science.
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Affiliation(s)
- Nicolai Lehnert
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Eunsuk Kim
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Hai T Dong
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Jill B Harland
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Andrew P Hunt
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Elizabeth C Manickas
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Kady M Oakley
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - John Pham
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Garrett C Reed
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Victor Sosa Alfaro
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
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12
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Quantifying Staphylococcus aureus Membrane Potential Using Flow Cytometry. Methods Mol Biol 2021. [PMID: 34264465 DOI: 10.1007/978-1-0716-1550-8_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Quantifying fluorescent markers in cell populations using flow cytometry has been a powerful technological advance. Fluorescent properties of cyanine dyes coupled with flow cytometry allow investigators to monitor the membrane potential (MP), an important component of the proton motive force (PMF). MP (or ΔΨ) is the electrical potential across the cell membrane. The other component of the PMF is ΔpH, or the difference in interior and exterior proton concentrations. MP plays a critical role in bacterial physiology. In Staphylococcus aureus, MP is required for generation of ATP, regulating autolytic activity, maintaining ion homeostasis, and resistance to some classes of antibiotics. This protocol exploits unique spectral and physical properties of the cyanine-based molecule diethyloxacarbocyanine iodide, or DiOC, and flow cytometry technology to quantify MP in S. aureus. This assay has been used by researchers to define the electron transport chain of S. aureus as well as determine how intrinsic and extrinsic factors affect MP.
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James KL, Rice KC. Best Practices for Preparation of Staphylococcus aureus Metabolomics Samples. Methods Mol Biol 2021; 2341:103-116. [PMID: 34264466 DOI: 10.1007/978-1-0716-1550-8_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Developments in mass spectrometry have made it possible to identify individual biomolecules in complex samples. This has led to advances in the detection and quantification of both extracellular and intracellular metabolites, such as amino acids, organic acids, fatty acids, nucleotides, and CoA-esters from growth media and cellular extracts. However, the reproducibility of metabolite data can be problematic if the concentrations and/or stability of metabolites fluctuate during culture harvesting and processing. Herein we describe a standardized and efficient collection protocol and best practices for preservation and harvesting of Staphylococcus aureus cellular and supernatant samples to improve reproducibility, reliability, and consistency in mass-spectrometry-based metabolite data sets.
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Affiliation(s)
- Kimberly L James
- Department of Microbiology and Cell Science, IFAS, University of Florida, Gainesville, FL, USA.
| | - Kelly C Rice
- Department of Microbiology and Cell Science, IFAS, University of Florida, Gainesville, FL, USA
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Orsini SS, James KL, Reyes DJ, Couto‐Rodriguez RL, Gulko MK, Witte A, Carroll RK, Rice KC. Bacterial-like nitric oxide synthase in the haloalkaliphilic archaeon Natronomonas pharaonis. Microbiologyopen 2020; 9:e1124. [PMID: 33306280 PMCID: PMC7658456 DOI: 10.1002/mbo3.1124] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 09/08/2020] [Accepted: 09/10/2020] [Indexed: 12/19/2022] Open
Abstract
Bacterial nitric oxide (NO) synthases (bNOS) play diverse and important roles in microbial physiology, stress resistance, and virulence. Although bacterial and mammalian NOS enzymes have been well-characterized, comparatively little is known about the prevalence and function of NOS enzymes in Archaea. Analysis of archaeal genomes revealed that highly conserved bNOS homologs were restricted to members of the Halobacteria. Of these, Natronomonas pharaonis NOS (npNOS) was chosen for further characterization. NO production was confirmed in heterologously expressed His-tagged npNOS by coupling nitrite production from N-hydroxy-L-arginine in an H2O2-supported reaction. Additionally, the nos gene was successfully targeted and disrupted to create a Nmn. pharaonis nos mutant by adapting an established Natrialba magadii transformation protocol. Genome re-sequencing of this mutant revealed an additional frameshift in a putative cation-acetate symporter gene, which could contribute to altered acetate metabolism in the nos mutant. Inactivation of Nmn. pharaonis nos was also associated with several phenotypes congruent with bacterial nos mutants (altered growth, increased oxygen consumption, increased pigment, increased UV susceptibility), suggesting that NOS function may be conserved between bacteria and archaea. These studies are the first to describe genetic inactivation and characterization of a Nmn. pharaonis gene and provides enhanced tools for probing its physiology.
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Affiliation(s)
- Silvia S. Orsini
- Department of Microbiology and Cell ScienceIFASUniversity of FloridaGainesvilleFLUSA
- Present address:
Pharma ServicesViral Vector ServicesThermo Fisher ScientificAlachuaFLUSA
| | - Kimberly L. James
- Department of Microbiology and Cell ScienceIFASUniversity of FloridaGainesvilleFLUSA
| | - Destiny J. Reyes
- Department of Microbiology and Cell ScienceIFASUniversity of FloridaGainesvilleFLUSA
- Present address:
Pharma ServicesViral Vector ServicesThermo Fisher ScientificAlachuaFLUSA
| | | | - Miriam K. Gulko
- Department OesterheltMax Planck Institut für BiochemieMartinsriedGermany
| | - Angela Witte
- Department of Microbiology, Immunobiology and GeneticsMPL LaboratoriesUniversity of ViennaViennaAustria
| | | | - Kelly C. Rice
- Department of Microbiology and Cell ScienceIFASUniversity of FloridaGainesvilleFLUSA
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Exogenous Fatty Acids Remodel Staphylococcus aureus Lipid Composition through Fatty Acid Kinase. J Bacteriol 2020; 202:JB.00128-20. [PMID: 32366591 DOI: 10.1128/jb.00128-20] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 04/29/2020] [Indexed: 12/30/2022] Open
Abstract
Staphylococcus aureus can utilize exogenous fatty acids for phospholipid synthesis. The fatty acid kinase FakA is essential for this utilization by phosphorylating exogenous fatty acids for incorporation into lipids. How FakA impacts the lipid membrane composition is unknown. In this study, we used mass spectrometry to determine the membrane lipid composition and properties of S. aureus in the absence of fakA We found the fakA mutant to have increased abundance of lipids containing longer acyl chains. Since S. aureus does not synthesize unsaturated fatty acids, we utilized oleic acid (18:1) to track exogenous fatty acid incorporation into lipids. We observed a concentration-dependent incorporation of exogenous fatty acids into the membrane that required FakA. We also tested how FakA and exogenous fatty acids impact membrane-related physiology and identified changes in membrane potential, cellular respiration, and membrane fluidity. To mimic the host environment, we characterized the lipid composition of wild-type and fakA mutant bacteria grown in mouse skin homogenate. We show that wild-type S. aureus can incorporate exogenous unsaturated fatty acids from host tissue, highlighting the importance of FakA in the presence of host skin tissue. In conclusion, FakA is important for maintaining the composition and properties of the phospholipid membrane in the presence of exogenous fatty acids, impacting overall cell physiology.IMPORTANCE Environmental fatty acids can be harvested to supplement endogenous fatty acid synthesis to produce membranes and circumvent fatty acid biosynthesis inhibitors. However, how the inability to use these fatty acids impacts lipids is unclear. Our results reveal lipid composition changes in response to fatty acid addition and when S. aureus is unable to activate fatty acids through FakA. We identify concentration-dependent utilization of oleic acid that, when combined with previous work, provides evidence that fatty acids can serve as a signal to S. aureus Furthermore, using mouse skin homogenates as a surrogate for in vivo conditions, we showed that S. aureus can incorporate host fatty acids. This study highlights how exogenous fatty acids impact bacterial membrane composition and function.
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Sakamoto T, Matsuura TR, Wan S, Ryba DM, Kim J, Won KJ, Lai L, Petucci C, Petrenko N, Musunuru K, Vega RB, Kelly DP. A Critical Role for Estrogen-Related Receptor Signaling in Cardiac Maturation. Circ Res 2020; 126:1685-1702. [PMID: 32212902 PMCID: PMC7274895 DOI: 10.1161/circresaha.119.316100] [Citation(s) in RCA: 75] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
RATIONALE The heart undergoes dramatic developmental changes during the prenatal to postnatal transition, including maturation of cardiac myocyte energy metabolic and contractile machinery. Delineation of the mechanisms involved in cardiac postnatal development could provide new insight into the fetal shifts that occur in the diseased heart and unveil strategies for driving maturation of stem cell-derived cardiac myocytes. OBJECTIVE To delineate transcriptional drivers of cardiac maturation. METHODS AND RESULTS We hypothesized that ERR (estrogen-related receptor) α and γ, known transcriptional regulators of postnatal mitochondrial biogenesis and function, serve a role in the broader cardiac maturation program. We devised a strategy to knockdown the expression of ERRα and γ in heart after birth (pn-csERRα/γ [postnatal cardiac-specific ERRα/γ]) in mice. With high levels of knockdown, pn-csERRα/γ knockdown mice exhibited cardiomyopathy with an arrest in mitochondrial maturation. RNA sequence analysis of pn-csERRα/γ knockdown hearts at 5 weeks of age combined with chromatin immunoprecipitation with deep sequencing and functional characterization conducted in human induced pluripotent stem cell-derived cardiac myocytes (hiPSC-CM) demonstrated that ERRγ activates transcription of genes involved in virtually all aspects of postnatal developmental maturation, including mitochondrial energy transduction, contractile function, and ion transport. In addition, ERRγ was found to suppress genes involved in fibroblast activation in hearts of pn-csERRα/γ knockdown mice. Disruption of Esrra and Esrrg in mice during fetal development resulted in perinatal lethality associated with structural and genomic evidence of an arrest in cardiac maturation, including persistent expression of early developmental and noncardiac lineage gene markers including cardiac fibroblast signatures. Lastly, targeted deletion of ESRRA and ESRRG in hiPSC-CM derepressed expression of early (transcription factor 21 or TCF21) and mature (periostin, collagen type III) fibroblast gene signatures. CONCLUSIONS ERRα and γ are critical regulators of cardiac myocyte maturation, serving as transcriptional activators of adult cardiac metabolic and structural genes, an.d suppressors of noncardiac lineages including fibroblast determination.
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Affiliation(s)
| | | | - Shibiao Wan
- Institute for Diabetes, Obesity and Metabolism, Dept. Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA
- Center for Applied Bioinformatics, St. Jude Children’s Research Hospital, Memphis, TN 38105
| | | | - Junil Kim
- Institute for Diabetes, Obesity and Metabolism, Dept. Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen, Denmark
| | - Kyoung Jae Won
- Institute for Diabetes, Obesity and Metabolism, Dept. Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen, Denmark
| | | | | | | | | | - Rick B. Vega
- Center for Metabolic Origins of Disease, Sanford Burnham Prebys Medical Discovery Institute at Lake Nona, Orlando, Florida, 32827, USA
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Lee JH, Go Y, Kim DY, Lee SH, Kim OH, Jeon YH, Kwon TK, Bae JH, Song DK, Rhyu IJ, Lee IK, Shong M, Oh BC, Petucci C, Park JW, Osborne TF, Im SS. Isocitrate dehydrogenase 2 protects mice from high-fat diet-induced metabolic stress by limiting oxidative damage to the mitochondria from brown adipose tissue. Exp Mol Med 2020; 52:238-252. [PMID: 32015410 PMCID: PMC7062825 DOI: 10.1038/s12276-020-0379-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 12/19/2019] [Accepted: 12/27/2019] [Indexed: 12/14/2022] Open
Abstract
Isocitrate dehydrogenase 2 (IDH2) is an NADP+-dependent enzyme that catalyzes the oxidative decarboxylation of isocitrate to α-ketoglutarate in the mitochondrial matrix, and is critical for the production of NADPH to limit the accumulation of mitochondrial reactive oxygen species (ROS). Here, we showed that high-fat diet (HFD) feeding resulted in accelerated weight gain in the IDH2KO mice due to a reduction in whole-body energy expenditure. Moreover, the levels of NADP+, NADPH, NAD+, and NADH were significantly decreased in the brown adipose tissue (BAT) of the HFD-fed IDH2KO animals, accompanied by decreased mitochondrial function and reduced expression of key genes involved in mitochondrial biogenesis, energy expenditure, and ROS resolution. Interestingly, these changes were partially reversed when the antioxidant butylated hydroxyanisole was added to the HFD. These observations reveal a crucial role for IDH2 in limiting ROS-dependent mitochondrial damage when BAT metabolism is normally enhanced to limit weight gain in response to dietary caloric overload.
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Affiliation(s)
- Jae-Ho Lee
- Department of Physiology, Keimyung University School of Medicine, Daegu, 42601 Republic of Korea
| | - Younghoon Go
- Department of Internal Medicine, School of Medicine Kyungpook National University, Kyungpook National University Hospital, Daegu, 41944 Republic of Korea
- Leading-Edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University Hospital, Daegu, 41404 South Korea
- Korean Medicine Application Center, Korea Institute of Oriental Medicine, Daegu, 41062 Republic of Korea
| | - Do-Young Kim
- Department of Physiology, Keimyung University School of Medicine, Daegu, 42601 Republic of Korea
| | - Sun Hee Lee
- Department of Physiology, Keimyung University School of Medicine, Daegu, 42601 Republic of Korea
| | - Ok-Hee Kim
- Department of Physiology, Lee Gil Ya Cancer and Diabetes Institute, Gachon University School of Medicine, Younsoo-gu, Inchon, 21999 Republic of Korea
| | - Yong Hyun Jeon
- Laboratory Animal Center, Daegu-Gyeongbuk Medical Innovation Foundation, Daegu, 41061 Republic of Korea
| | - Taeg Kyu Kwon
- Department of Immunology, Keimyung University School of Medicine, Daegu, 42601 Republic of Korea
| | - Jae-Hoon Bae
- Department of Physiology, Keimyung University School of Medicine, Daegu, 42601 Republic of Korea
| | - Dae-Kyu Song
- Department of Physiology, Keimyung University School of Medicine, Daegu, 42601 Republic of Korea
| | - Im Joo Rhyu
- Department of Anatomy, Korea University College of Medicine, Seoul, 02841 Republic of Korea
| | - In-Kyu Lee
- Department of Internal Medicine, School of Medicine Kyungpook National University, Kyungpook National University Hospital, Daegu, 41944 Republic of Korea
- Leading-Edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University Hospital, Daegu, 41404 South Korea
| | - Minho Shong
- Research Center for Endocrinology and Metabolism, Chungnam National University Hospital (CNUH), 282 Munhwaro, Daejeon, 35015 Republic of Korea
| | - Byung-Chul Oh
- Department of Physiology, Lee Gil Ya Cancer and Diabetes Institute, Gachon University School of Medicine, Younsoo-gu, Inchon, 21999 Republic of Korea
| | - Christopher Petucci
- Center for Metabolic Origins of Disease, Sanford Burnham Prebys Medical Discovery Institute, Orlando, FL 32827 USA
- Cardiovascular Institute and Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Jeen-Woo Park
- School of Life Sciences and Biotechnology, College of Natural Science, Kyungpook National University, Daegu, 41566 Republic of Korea
| | - Timothy F. Osborne
- Institute for Fundamental Biomedical Research, Department of Medicine and Biological Chemistry, Johns Hopkins University School of Medicine, St. Petersburg, FL 33701 USA
| | - Seung-Soon Im
- Department of Physiology, Keimyung University School of Medicine, Daegu, 42601 Republic of Korea
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18
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Reactive nitrogen species in host-bacterial interactions. Curr Opin Immunol 2019; 60:96-102. [PMID: 31200187 DOI: 10.1016/j.coi.2019.05.008] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 04/29/2019] [Accepted: 05/11/2019] [Indexed: 12/11/2022]
Abstract
Reactive nitrogen species play diverse and essential roles in host-pathogen interactions. Here, we review selected recent discoveries regarding nitric oxide (NO) in host defense and the pathogenesis of infection, mechanisms of bacterial NO resistance, production of NO by human macrophages, NO-based antimicrobial therapeutics and NO interactions with the gut microbiota.
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Proctor R. Respiration and Small Colony Variants of Staphylococcus aureus. Microbiol Spectr 2019; 7:10.1128/microbiolspec.gpp3-0069-2019. [PMID: 31198131 PMCID: PMC11257146 DOI: 10.1128/microbiolspec.gpp3-0069-2019] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2018] [Indexed: 12/16/2022] Open
Abstract
Respiratory mutants, both naturally occurring and genetically constructed, have taught us about the importance of metabolism in influencing virulence factor production, persistence, and antibiotic resistance. As we learn more about small colony variants, we find that Staphylococcus aureus has many pathways to produce small colony variants, although the respiratory variants are the best described clinically and in the laboratory.
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Affiliation(s)
- Richard Proctor
- Department of Medical Microbiology and Immunology University of Wisconsin School of Medicine and Public Health Madison, WI 53705
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20
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The Response of nor and nos Contributes to Staphylococcus aureus Virulence and Metabolism. J Bacteriol 2019; 201:JB.00107-19. [PMID: 30782631 DOI: 10.1128/jb.00107-19] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 02/06/2019] [Indexed: 12/21/2022] Open
Abstract
Staphylococcus aureus causes a wide spectrum of disease, with the site and severity of infection dependent on virulence traits encoded within genetically distinct clonal complexes (CCs) and bacterial responses to host innate immunity. The production of nitric oxide (NO) by activated phagocytes is a major host response to which S. aureus metabolically adapts through multiple strategies that are conserved in all CCs, including an S. aureus nitric oxide synthase (Nos). Previous genome analysis of CC30, a lineage associated with chronic endocardial and osteoarticular infections, revealed a putative NO reductase (Nor) not found in other CCs that potentially contributes to NO resistance and clinical outcome. Here, we demonstrate that Nor has true nitric oxide reductase activity, with nor expression enhanced by NO stress and anaerobic growth. Furthermore, we demonstrate that nor is regulated by MgrA and SrrAB, which modulate S. aureus virulence and hypoxic response. Transcriptome analysis of the S. aureus UAMS-1, UAMS-1 Δnor, and UAMS-1 Δnos strains under NO stress and anaerobic growth demonstrates that Nor contributes to nucleotide metabolism and Nos to glycolysis. We demonstrate that Nor and Nos contribute to enhanced survival in the presence of human human polymorphonuclear cells and have organ-specific seeding in a tail vein infection model. Nor contributes to abscess formation in an osteological implant model. We also demonstrate that Nor has a role in S. aureus metabolism and virulence. The regulation overlap between Nor and Nos points to an intriguing link between regulation of intracellular NO, metabolic adaptation, and persistence in the CC30 lineage.IMPORTANCE Staphylococcus aureus can cause disease at most body sites, and illness spans asymptomatic infection to death. The variety of clinical presentations is due to the diversity of strains, which are grouped into distinct clonal complexes (CCs) based on genetic differences. The ability of S. aureus CC30 to cause chronic infections relies on its ability to evade the oxidative/nitrosative defenses of the immune system and survive under different environmental conditions, including differences in oxygen and nitric oxide concentrations. The significance of this work is the exploration of unique genes involved in resisting NO stress and anoxia. A better understanding of the functions that control the response of S. aureus CC30 to NO and oxygen will guide the treatment of severe disease presentations.
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Interplay of Nitric Oxide Synthase (NOS) and SrrAB in Modulation of Staphylococcus aureus Metabolism and Virulence. Infect Immun 2019; 87:IAI.00570-18. [PMID: 30420450 DOI: 10.1128/iai.00570-18] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 10/26/2018] [Indexed: 12/15/2022] Open
Abstract
Staphylococcus aureus nitric oxide synthase (saNOS) is a major contributor to virulence, stress resistance, and physiology, yet the specific mechanism(s) by which saNOS intersects with other known regulatory circuits is largely unknown. The SrrAB two-component system, which modulates gene expression in response to the reduced state of respiratory menaquinones, is a positive regulator of nos expression. Several SrrAB-regulated genes were also previously shown to be induced in an aerobically respiring nos mutant, suggesting a potential interplay between saNOS and SrrAB. Therefore, a combination of genetic, molecular, and physiological approaches was employed to characterize a nos srrAB mutant, which had significant reductions in the maximum specific growth rate and oxygen consumption when cultured under conditions promoting aerobic respiration. The nos srrAB mutant secreted elevated lactate levels, correlating with the increased transcription of lactate dehydrogenases. Expression of nitrate and nitrite reductase genes was also significantly enhanced in the nos srrAB double mutant, and its aerobic growth defect could be partially rescued with supplementation with nitrate, nitrite, or ammonia. Furthermore, elevated ornithine and citrulline levels and highly upregulated expression of arginine deiminase genes were observed in the double mutant. These data suggest that a dual deficiency in saNOS and SrrAB limits S. aureus to fermentative metabolism, with a reliance on nitrate assimilation and the urea cycle to help fuel energy production. The nos, srrAB, and nos srrAB mutants showed comparable defects in endothelial intracellular survival, whereas the srrAB and nos srrAB mutants were highly attenuated during murine sepsis, suggesting that SrrAB-mediated metabolic versatility is dominant in vivo.
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Redirection of Metabolism in Response to Fatty Acid Kinase in Staphylococcus aureus. J Bacteriol 2018; 200:JB.00345-18. [PMID: 30012726 DOI: 10.1128/jb.00345-18] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 07/06/2018] [Indexed: 12/23/2022] Open
Abstract
Staphylococcus aureus is capable of phosphorylating exogenous fatty acids for incorporation into the bacterium's membrane via the fatty acid kinase, FakA. Additionally, FakA plays a significant role in virulence factor regulation and skin infections. We previously showed that a fakA mutant displays altered growth kinetics in vitro, observed during the late-exponential phase of growth. Here, we demonstrate that the absence of FakA leads to key metabolic changes. First, the fakA mutant has an altered acetate metabolism, with acetate being consumed at an increased rate than in the wild-type strain. Moreover, the growth benefit was diminished with inactivation of the acetate-generating enzyme AckA. Using a mass spectrometry-based approach, we identified altered concentrations of tricarboxylic acid (TCA) cycle intermediates and both intracellular and extracellular amino acids. Together, these data demonstrate a change in carbohydrate carbon utilization and altered amino acid metabolism in the fakA mutant. Energy status analysis revealed the mutant had a similar ADP/ATP ratio to that of the wild type, but a reduced adenylate energy charge. The inactivation of fakA changed the NAD+/NADH and NADP+/NADPH ratios, indicating a more oxidized cellular environment. Evidence points to the global metabolic regulatory proteins CcpA and CodY being important contributors to the altered growth in a fakA mutant. Indeed, it was found that directing amino acids from the urea cycle into the TCA cycle via glutamate dehydrogenase was an essential component of S. aureus growth after glucose depletion. Together, these data identify a previously unidentified role of FakA in the global physiology of S. aureus, linking external fatty acid utilization and central metabolism.IMPORTANCE The fatty acid kinase, FakA, of Staphylococcus aureus plays several important roles in the cell. FakA is important for the activation of the SaeRS two-component system and secreted virulence factors like α-hemolysin. However, the contribution of FakA to cellular metabolism has not been explored. Here, we highlight the metabolic consequence of removal of FakA from the cell. The absence of FakA leads to altered acetate metabolism and altered redox balance, as well as a change in intracellular amino acids. Additionally, the use of environmental amino acid sources is affected by FakA. Together, these results demonstrate for the first time that FakA provides a link between the pathways for exogenous fatty acid use, virulence factor regulation, and other metabolic processes.
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Correa-Aragunde N, Foresi N, Del Castello F, Lamattina L. A singular nitric oxide synthase with a globin domain found in Synechococcus PCC 7335 mobilizes N from arginine to nitrate. Sci Rep 2018; 8:12505. [PMID: 30131503 PMCID: PMC6104048 DOI: 10.1038/s41598-018-30889-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 08/07/2018] [Indexed: 12/11/2022] Open
Abstract
The enzyme nitric oxide synthase (NOS) oxidizes L-arginine to NO and citrulline. In this work, we characterise the NOS from the cyanobacteria Synechococcus PCC 7335 (SyNOS). SyNOS possesses a canonical mammalian NOS architecture consisting of oxygenase and reductase domains. In addition, SyNOS possesses an unusual globin domain at the N-terminus. Recombinant SyNOS expressed in bacteria is active, and its activity is suppressed by the NOS inhibitor L-NAME. SyNOS allows E. coli to grow in minimum media containing L-arginine as the sole N source, and has a higher growth rate during N deficiency. SyNOS is expressed in Synechococcus PCC 7335 where NO generation is dependent on L-arginine concentration. The growth of Synechococcus is dramatically inhibited by L-NAME, suggesting that SyNOS is essential for this cyanobacterium. Addition of arginine in Synechococcus increases the phycoerythrin content, an N reservoir. The role of the novel globin domain in SyNOS is discussed as an evolutionary advantage, conferring new functional capabilities for N metabolism.
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Affiliation(s)
- Natalia Correa-Aragunde
- Instituto de Investigaciones Biológicas. Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata - CONICET, CC 1245, 7600, Mar del Plata, Argentina
| | - Noelia Foresi
- Instituto de Investigaciones Biológicas. Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata - CONICET, CC 1245, 7600, Mar del Plata, Argentina
| | - Fiorella Del Castello
- Instituto de Investigaciones Biológicas. Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata - CONICET, CC 1245, 7600, Mar del Plata, Argentina
| | - Lorenzo Lamattina
- Instituto de Investigaciones Biológicas. Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata - CONICET, CC 1245, 7600, Mar del Plata, Argentina.
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Ras G, Leroy S, Talon R. Nitric oxide synthase: What is its potential role in the physiology of staphylococci in meat products? Int J Food Microbiol 2018; 282:28-34. [PMID: 29890305 DOI: 10.1016/j.ijfoodmicro.2018.06.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 05/23/2018] [Accepted: 06/06/2018] [Indexed: 12/17/2022]
Abstract
Coagulase-negative staphylococci are frequently isolated from meat products and two species are used as starter cultures in dry fermented sausages. In these products, they face various environmental conditions such as variation of redox potential and oxygen levels that can lead to oxidative stress. Furthermore, when nitrate and nitrite are added as curing salts, staphylococci also experience nitrosative stress. A nos gene encoding a nitric oxide synthase (NOS) is present in the genome of all staphylococci. NOS produces nitric oxide (NO) and citrulline from arginine, but its activity is still poorly characterized, particularly in coagulase-negative staphylococci. NO is highly reactive with a broad spectrum of activity resulting from targeting metal centres (heme and non-heme) and protein thiols. At low concentration, NO acts as a signalling molecule, while at higher concentration it generates stress. Thus, it was initially suggested that staphylococcal NOS counteract oxidative stress in relation to PerR and Fur regulators. In the physiology of staphylococci, it has recently been highlighted that NO controls the rate of aerobic respiration and regulates the transition from aerobic to nitrate respiration and also helps maintain the membrane potential in relation to the two-component systems SrrAB and AirRS. As NO interacts with heme centres, it binds the heme iron atom of myoglobin to form nitrosomyglobin, which is the typical red pigment of cured meat. However, the contribution of NOS to this reaction in meat products has yet to be evaluated.
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Affiliation(s)
- Geoffrey Ras
- Université Clermont Auvergne, INRA, MEDIS, Clermont-Ferrand, France; CHR. HANSEN SAS, Saint-Germain-les-Arpajon, France
| | - Sabine Leroy
- Université Clermont Auvergne, INRA, MEDIS, Clermont-Ferrand, France
| | - Régine Talon
- Université Clermont Auvergne, INRA, MEDIS, Clermont-Ferrand, France.
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Choby JE, Grunenwald CM, Celis AI, Gerdes SY, DuBois JL, Skaar EP. Staphylococcus aureus HemX Modulates Glutamyl-tRNA Reductase Abundance To Regulate Heme Biosynthesis. mBio 2018; 9:e02287-17. [PMID: 29437922 PMCID: PMC5801465 DOI: 10.1128/mbio.02287-17] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 01/08/2018] [Indexed: 12/30/2022] Open
Abstract
Staphylococcus aureus is responsible for a significant amount of devastating disease. Its ability to colonize the host and cause infection is supported by a variety of proteins that are dependent on the cofactor heme. Heme is a porphyrin used broadly across kingdoms and is synthesized de novo from common cellular precursors and iron. While heme is critical to bacterial physiology, it is also toxic in high concentrations, requiring that organisms encode regulatory processes to control heme homeostasis. In this work, we describe a posttranscriptional regulatory strategy in S. aureus heme biosynthesis. The first committed enzyme in the S. aureus heme biosynthetic pathway, glutamyl-tRNA reductase (GtrR), is regulated by heme abundance and the integral membrane protein HemX. GtrR abundance increases dramatically in response to heme deficiency, suggesting a mechanism by which S. aureus responds to the need to increase heme synthesis. Additionally, HemX is required to maintain low levels of GtrR in heme-proficient cells, and inactivation of hemX leads to increased heme synthesis. Excess heme synthesis in a ΔhemX mutant activates the staphylococcal heme stress response, suggesting that regulation of heme synthesis is critical to reduce self-imposed heme toxicity. Analysis of diverse organisms indicates that HemX is widely conserved among heme-synthesizing bacteria, suggesting that HemX is a common factor involved in the regulation of GtrR abundance. Together, this work demonstrates that S. aureus regulates heme synthesis by modulating GtrR abundance in response to heme deficiency and through the activity of the broadly conserved HemX.IMPORTANCEStaphylococcus aureus is a leading cause of skin and soft tissue infections, endocarditis, bacteremia, and osteomyelitis, making it a critical health care concern. Development of new antimicrobials against S. aureus requires knowledge of the physiology that supports this organism's pathogenesis. One component of staphylococcal physiology that contributes to growth and virulence is heme. Heme is a widely utilized cofactor that enables diverse chemical reactions across many enzyme families. S. aureus relies on many critical heme-dependent proteins and is sensitive to excess heme toxicity, suggesting S. aureus must maintain proper intracellular heme homeostasis. Because S. aureus provides heme for heme-dependent enzymes via synthesis from common precursors, we hypothesized that regulation of heme synthesis is one mechanism to maintain heme homeostasis. In this study, we identify that S. aureus posttranscriptionally regulates heme synthesis by restraining abundance of the first heme biosynthetic enzyme, GtrR, via heme and the broadly conserved membrane protein HemX.
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Affiliation(s)
- Jacob E Choby
- Department of Pathology, Microbiology, & Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Graduate Program in Microbiology & Immunology, Vanderbilt University, Nashville, Tennessee, USA
| | - Caroline M Grunenwald
- Department of Pathology, Microbiology, & Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Arianna I Celis
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana, USA
| | | | - Jennifer L DuBois
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana, USA
| | - Eric P Skaar
- Department of Pathology, Microbiology, & Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee, USA
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