1
|
Chen X, Liu P, Wang J, He X, Wang J, Chen H, Wang G. TMT-Based Quantitative Proteomics Revealed the Antibacterial Mechanism of Cinnamaldehyde against MRSA. J Proteome Res 2024. [PMID: 39269200 DOI: 10.1021/acs.jproteome.4c00520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/15/2024]
Abstract
Natural plant extracts have demonstrated significant potential in alternative antibiotic therapies. Cinnamaldehyde (CA) has garnered considerable attention as a natural antibacterial agent. In this study, Tandem mass tag (TMT) quantitative proteomics combined with Western blot and RT-qPCR methods were employed to explore the antibacterial mechanism of CA against Methicillin-Resistant Staphylococcus aureus (MRSA) at the protein level. The results showed that a total of 254 differentially expressed proteins (DEPs) were identified in the control group and CA treatment group, of which 161 were significantly upregulated and 93 were significantly downregulated. DEPs related to nucleotide synthesis, homeostasis of the internal environment, and protein biosynthesis were significantly upregulated, while DEPs involved in the cell wall, cell membrane, and virulence factors were significantly downregulated. The results of GO and KEGG enrichment analyses demonstrated that CA could exert its antibacterial effects by influencing pyruvate metabolism, the tricarboxylic acid (TCA) cycle, teichoic acid biosynthesis, and the Staphylococcus aureus (S. aureus) infection pathway in MRSA. CA significantly inhibited the expression of recombinant protein MgrA (p < 0.05), significantly reduced the mRNA transcription levels of mgrA, hla, and sdrD genes (p < 0.05), and thermostability migration assays demonstrated that CA can directly interact with MgrA protein, thereby inhibiting its activity. These findings suggest that CA exerts its antibacterial mechanism by regulating the expression of related proteins, providing a theoretical basis for further development of clinical applications of antimicrobial agents derived from natural plant essential oils in the treatment of dairy cow mastitis.
Collapse
Affiliation(s)
- Xiaohui Chen
- College of Animal Science and Technology, Ningxia University, Yinchuan 750021, China
| | - Panpan Liu
- College of Animal Science and Technology, Ningxia University, Yinchuan 750021, China
| | - Jingge Wang
- College of Animal Science and Technology, Ningxia University, Yinchuan 750021, China
| | - Xiaoqiang He
- College of Animal Science and Technology, Ningxia University, Yinchuan 750021, China
| | - Jianchong Wang
- College of Animal Science and Technology, Ningxia University, Yinchuan 750021, China
| | - Haorong Chen
- College of Animal Science and Technology, Ningxia University, Yinchuan 750021, China
| | - Guiqin Wang
- College of Animal Science and Technology, Ningxia University, Yinchuan 750021, China
| |
Collapse
|
2
|
Lei MG, Jorgenson MA, Robbs EJ, Black IM, Archer-Hartmann S, Shalygin S, Azadi P, Lee CY. Characterization of Ssc, an N-acetylgalactosamine-containing Staphylococcus aureus surface polysaccharide. J Bacteriol 2024; 206:e0004824. [PMID: 38712944 PMCID: PMC11112989 DOI: 10.1128/jb.00048-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2024] [Accepted: 04/08/2024] [Indexed: 05/08/2024] Open
Abstract
Whole genome sequencing has revealed that the genome of Staphylococcus aureus possesses an uncharacterized 5-gene operon (SAOUHSC_00088-00092 in strain 8325 genome) that encodes factors with functions related to polysaccharide biosynthesis and export, indicating the existence of a new extracellular polysaccharide species. We designate this locus as ssc for staphylococcal surface carbohydrate. We found that the ssc genes were weakly expressed and highly repressed by the global regulator MgrA. To characterize Ssc, Ssc was heterologously expressed in Escherichia coli and extracted by heat treatment. Ssc was also conjugated to AcrA from Campylobacter jejuni in E. coli using protein glycan coupling technology (PGCT). Analysis of the heat-extracted Ssc and the purified Ssc-AcrA glycoconjugate by tandem mass spectrometry revealed that Ssc is likely a polymer consisting of N-acetylgalactosamine. We further demonstrated that the expression of the ssc genes in S. aureus affected phage adsorption and susceptibility, suggesting that Ssc is surface-exposed. IMPORTANCE Surface polysaccharides play crucial roles in the biology and virulence of bacterial pathogens. Staphylococcus aureus produces four major types of polysaccharides that have been well-characterized. In this study, we identified a new surface polysaccharide containing N-acetylgalactosamine (GalNAc). This marks the first report of GalNAc-containing polysaccharide in S. aureus. Our discovery lays the groundwork for further investigations into the chemical structure, surface location, and role in pathogenesis of this new polysaccharide.
Collapse
Affiliation(s)
- Mei G. Lei
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Matthew A. Jorgenson
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Emily J. Robbs
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Ian M. Black
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA
| | | | - Sergei Shalygin
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA
| | - Parastoo Azadi
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA
| | - Chia Y. Lee
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| |
Collapse
|
3
|
Campbell MJ, Beenken KE, Ramirez AM, Smeltzer MS. The major role of sarA in limiting Staphylococcus aureus extracellular protease production in vitro is correlated with decreased virulence in diverse clinical isolates in osteomyelitis. Virulence 2023; 14:2175496. [PMID: 36748843 PMCID: PMC9928472 DOI: 10.1080/21505594.2023.2175496] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
We previously demonstrated that MgrA, SarA, SarR, SarS, SarZ, and Rot bind at least three of the four promoters associated with genes encoding primary extracellular proteases in Staphylococcus aureus (Aur, ScpA, SspA/SspB, SplA-F). We also showed that mutation of sarA results in a greater increase in protease production, and decrease in biofilm formation, than mutation of the loci encoding any of these other proteins. However, these conclusions were based on in vitro studies. Thus, the goal of the experiments reported here was to determine the relative impact of the regulatory loci encoding these proteins in vivo. To this end, we compared the virulence of mgrA, sarA, sarR, sarS, sarZ, and rot mutants in a murine osteomyelitis model. Mutants were generated in the methicillin-resistant USA300 strain LAC and the methicillin-sensitive USA200 strain UAMS-1, which was isolated directly from the bone of an osteomyelitis patient during surgical debridement. Mutation of mgrA and rot limited virulence to a statistically significant extent in UAMS-1, but not in LAC, while the sarA mutant exhibited reduced virulence in both strains. The reduced virulence of the sarA mutant was correlated with reduced cytotoxicity for osteoblasts and osteoclasts, reduced biofilm formation, and reduced sensitivity to the antimicrobial peptide indolicidin, all of which were directly attributable to increased protease production in both LAC and UAMS-1. These results illustrate the importance of considering diverse clinical isolates when evaluating the impact of regulatory mutations on virulence and demonstrate the significance of SarA in limiting protease production in vivo in S. aureus.
Collapse
Affiliation(s)
- Mara J. Campbell
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Karen E. Beenken
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Aura M. Ramirez
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | | |
Collapse
|
4
|
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.
Collapse
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
| |
Collapse
|
5
|
Key FM, Khadka VD, Romo-González C, Blake KJ, Deng L, Lynn TC, Lee JC, Chiu IM, García-Romero MT, Lieberman TD. On-person adaptive evolution of Staphylococcus aureus during treatment for atopic dermatitis. Cell Host Microbe 2023; 31:593-603.e7. [PMID: 37054679 PMCID: PMC10263175 DOI: 10.1016/j.chom.2023.03.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Revised: 02/14/2023] [Accepted: 03/10/2023] [Indexed: 04/15/2023]
Abstract
The opportunistic pathogen Staphylococcus aureus frequently colonizes the inflamed skin of people with atopic dermatitis (AD) and worsens disease severity by promoting skin damage. Here, we show, by longitudinally tracking 23 children treated for AD, that S. aureus adapts via de novo mutations during colonization. Each patient's S. aureus population is dominated by a single lineage, with infrequent invasion by distant lineages. Mutations emerge within each lineage at rates similar to those of S. aureus in other contexts. Some variants spread across the body within months, with signatures of adaptive evolution. Most strikingly, mutations in capsule synthesis gene capD underwent parallel evolution in one patient and across-body sweeps in two patients. We confirm that capD negativity is more common in AD than in other contexts, via reanalysis of S. aureus genomes from 276 people. Together, these findings highlight the importance of the mutation level when dissecting the role of microbes in complex disease.
Collapse
Affiliation(s)
- Felix M Key
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA; Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Veda D Khadka
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA; Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Carolina Romo-González
- Experimental Bacteriology Laboratory, National Institute for Pediatrics, Mexico City, Mexico
| | - Kimbria J Blake
- Department of Immunology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Liwen Deng
- Department of Immunology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Tucker C Lynn
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA; Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Jean C Lee
- Division of Infectious Disease, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Isaac M Chiu
- Department of Immunology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | | | - Tami D Lieberman
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA; Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA; Broad Institute, Massachusetts Institute of Technology, Cambridge, MA, USA; Ragon Institute, Massachusetts Institute of Technology, Cambridge, MA, USA.
| |
Collapse
|
6
|
Costa MDOCE, do Nascimento APB, Martins YC, dos Santos MT, Figueiredo AMDS, Perez-Rueda E, Nicolás MF. The gene regulatory network of Staphylococcus aureus ST239-SCC mecIII strain Bmb9393 and assessment of genes associated with the biofilm in diverse backgrounds. Front Microbiol 2023; 13:1049819. [PMID: 36704545 PMCID: PMC9871828 DOI: 10.3389/fmicb.2022.1049819] [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: 09/21/2022] [Accepted: 12/19/2022] [Indexed: 01/12/2023] Open
Abstract
Introduction Staphylococcus aureus is one of the most prevalent and relevant pathogens responsible for a wide spectrum of hospital-associated or community-acquired infections. In addition, methicillin-resistant Staphylococcus aureus may display multidrug resistance profiles that complicate treatment and increase the mortality rate. The ability to produce biofilm, particularly in device-associated infections, promotes chronic and potentially more severe infections originating from the primary site. Understanding the complex mechanisms involved in planktonic and biofilm growth is critical to identifying regulatory connections and ways to overcome the global health problem of multidrug-resistant bacteria. Methods In this work, we apply literature-based and comparative genomics approaches to reconstruct the gene regulatory network of the high biofilm-producing strain Bmb9393, belonging to one of the highly disseminating successful clones, the Brazilian epidemic clone. To the best of our knowledge, we describe for the first time the topological properties and network motifs for the Staphylococcus aureus pathogen. We performed this analysis using the ST239-SCCmecIII Bmb9393 strain. In addition, we analyzed transcriptomes available in the literature to construct a set of genes differentially expressed in the biofilm, covering different stages of the biofilms and genetic backgrounds of the strains. Results and discussion The Bmb9393 gene regulatory network comprises 1,803 regulatory interactions between 64 transcription factors and the non-redundant set of 1,151 target genes with the inclusion of 19 new regulons compared to the N315 transcriptional regulatory network published in 2011. In the Bmb9393 network, we found 54 feed-forward loop motifs, where the most prevalent were coherent type 2 and incoherent type 2. The non-redundant set of differentially expressed genes in the biofilm consisted of 1,794 genes with functional categories relevant for adaptation to the variable microenvironments established throughout the biofilm formation process. Finally, we mapped the set of genes with altered expression in the biofilm in the Bmb9393 gene regulatory network to depict how different growth modes can alter the regulatory systems. The data revealed 45 transcription factors and 876 shared target genes. Thus, the gene regulatory network model provided represents the most up-to-date model for Staphylococcus aureus, and the set of genes altered in the biofilm provides a global view of their influence on biofilm formation from distinct experimental perspectives and different strain backgrounds.
Collapse
Affiliation(s)
| | - Ana Paula Barbosa do Nascimento
- Departamento de Análises Clínicas e Toxicológicas, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, Brazil
| | | | | | - Agnes Marie de Sá Figueiredo
- Instituto de Investigaciones en Matemáticas Aplicadas y en Sistemas, Universidad Nacional Autónoma de México, Unidad Académica Yucatán, Merida, Mexico
| | - Ernesto Perez-Rueda
- Laboratório de Biologia Molecular de Bactérias, Instituto de Microbiologia Paulo de Goés, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil,*Correspondence: Ernesto Perez-Rueda ✉
| | - Marisa Fabiana Nicolás
- Laboratório Nacional de Computação Científica (LNCC), Petrópolis, Brazil,Marisa Fabiana Nicolás ✉
| |
Collapse
|
7
|
Regulation of Staphylococcal Capsule by SarZ is SigA-Dependent. J Bacteriol 2022; 204:e0015222. [PMID: 35862799 PMCID: PMC9380528 DOI: 10.1128/jb.00152-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Production of capsular polysaccharides in Staphylococcus aureus is transcriptionally regulated by a control region of the cap operon that consists of SigA- and SigB-dependent promoters. A large number of regulators have been shown to affect cap gene expression. However, regulation of capsule is only partially understood. Here we found that SarZ was another regulator that activated the cap genes through the SigA-dependent promoter. Gel electrophoresis mobility shift experiments revealed that SarZ is bound to a broad region of the cap promoter including the SigA-dependent promoter but mainly the downstream region. We demonstrated that activation of cap expression by SarZ was independent of MgrA, which also activated capsule through the SigA-dependent promoter. Our results further showed that oxidative stress with hydrogen peroxide (H2O2) treatments enhanced SarZ activation of cap expression, indicating that SarZ is able to sense oxidative stress to regulate capsule production. IMPORTANCE Expression of virulence genes in Staphylococcus aureus is affected by environmental cues and is regulated by a surprisingly large number of regulators. Much is still unknown about how virulence factors are regulated by environment cues at the molecular level. Capsule is an antiphagocytic virulence factor that is highly regulated. In this study, we found SarZ was an activator of capsule and that the regulation of capsule by SarZ was affected by oxidative stress. These results provide an example of how a virulence factor could be regulated in response to an environmental cue. As the host oxidative defense system plays an important role against S. aureus, this study contributes to a better understanding of virulence gene regulation and staphylococcal pathogenesis.
Collapse
|
8
|
Altwiley D, Brignoli T, Edwards A, Recker M, Lee JC, Massey RC. A functional menadione biosynthesis pathway is required for capsule production by Staphylococcus aureus. MICROBIOLOGY (READING, ENGLAND) 2021; 167. [PMID: 34825882 PMCID: PMC8743628 DOI: 10.1099/mic.0.001108] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Staphylococcus aureus is a major human pathogen that utilises a wide array of pathogenic and immune evasion strategies to cause disease. One immune evasion strategy, common to many bacterial pathogens, is the ability of S. aureus to produce a capsule that protects the bacteria from several aspects of the human immune system. To identify novel regulators of capsule production by S. aureus, we applied a genome wide association study (GWAS) to a collection of 300 bacteraemia isolates that represent the two major MRSA clones in UK and Irish hospitals: CC22 and CC30. One of the loci associated with capsule production, the menD gene, encodes an enzyme critical to the biosynthesis of menadione. Mutations in this gene that result in menadione auxotrophy induce the slow growing small-colony variant (SCV) form of S. aureus often associated with chronic infections due to their increased resistance to antibiotics and ability to survive inside phagocytes. Utilising such an SCV, we functionally verified this association between menD and capsule production. Although the clinical isolates with polymorphisms in the menD gene in our collections had no apparent growth defects, they were more resistant to gentamicin when compared to those with the wild-type menD gene. Our work suggests that menadione is involved in the production of the S. aureus capsule, and that amongst clinical isolates polymorphisms exist in the menD gene that confer the characteristic increased gentamicin resistance, but not the major growth defect associated with SCV phenotype.
Collapse
Affiliation(s)
- Dina Altwiley
- School of Cellular and Molecular Medicine, University of Bristol, BS8 1TD, UK.,University of Jeddah, Saudi Arabia
| | - Tarcisio Brignoli
- School of Cellular and Molecular Medicine, University of Bristol, BS8 1TD, UK
| | - Andrew Edwards
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, SW7 2AZ, UK
| | - Mario Recker
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, TR10 9FE, UK
| | - Jean C Lee
- Division of Infectious Diseases, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Ruth C Massey
- School of Cellular and Molecular Medicine, University of Bristol, BS8 1TD, UK.,Schools of Microbiology and Medicine, and APC Microbiome Ireland, University College Cork, Ireland
| |
Collapse
|