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Zhu X, Liang Z, Ma J, Huang J, Wang L, Yao H, Wu Z. The cadDX operon contributes to cadmium resistance, oxidative stress resistance, and virulence in zoonotic streptococci. Vet Res 2024; 55:119. [PMID: 39334407 PMCID: PMC11430099 DOI: 10.1186/s13567-024-01371-1] [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: 07/01/2024] [Accepted: 08/13/2024] [Indexed: 09/30/2024] Open
Abstract
Mobile genetic elements (MGEs) enable bacteria to acquire novel genes and traits. However, the functions of cargo genes within MGEs remain poorly understood. The cadmium resistance operon cadDX is present in many gram-positive bacteria. Although cadDX has been reported to be involved in metal detoxification, its regulatory mechanisms and functions in bacterial pathogenesis are poorly understood. This study revealed that cadDX contributes to cadmium resistance, oxidative stress resistance, and virulence in Streptococcus suis, an important zoonotic pathogen in pigs and humans. CadX represses cadD expression by binding to the cadDX promoter. Notably, cadX responds to H2O2 stress through an additional promoter within the cadDX operon, mitigating the harmful effect of excessive cadD expression during oxidative stress. cadDX resides within an 11 K integrative and mobilizable element that can autonomously form circular structures. Moreover, cadDX is found in diverse MGEs, accounting for its widespread distribution across various bacteria, especially among pathogenic streptococci. Transferring cadDX into another zoonotic pathogen, Streptococcus agalactiae, results in similar phenotypes, including resistance to cadmium and oxidative stresses and increased virulence of S. agalactiae in mice. The new functions and regulatory mechanisms of cadDX shed light on the importance of the cadDX system in driving evolutionary adaptations and survival strategies across diverse gram-positive bacteria.
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Affiliation(s)
- Xinchi Zhu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210014, China
- Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing, 210014, China
- WOAH Reference Lab for Swine Streptococcosis, Nanjing, 210014, China
| | - Zijing Liang
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210014, China
- Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing, 210014, China
- WOAH Reference Lab for Swine Streptococcosis, Nanjing, 210014, China
| | - Jiale Ma
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210014, China
- Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing, 210014, China
- WOAH Reference Lab for Swine Streptococcosis, Nanjing, 210014, China
| | - Jinhu Huang
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210014, China
| | - Liping Wang
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210014, China
| | - Huochun Yao
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210014, China
- Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing, 210014, China
- WOAH Reference Lab for Swine Streptococcosis, Nanjing, 210014, China
| | - Zongfu Wu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210014, China.
- Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing, 210014, China.
- WOAH Reference Lab for Swine Streptococcosis, Nanjing, 210014, China.
- Guangdong Provincial Key Laboratory of Research On the Technology of Pig Breeding and Pig Disease Prevention, Guangzhou, 511400, China.
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Shull LM, Wolter DJ, Kunkle DE, Legg KA, Giedroc DP, Skaar EP, Hoffman LR, Reniere ML. Analysis of genetic requirements and nutrient availability for Staphylococcus aureus growth in cystic fibrosis sputum. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.09.24.614743. [PMID: 39386554 PMCID: PMC11463553 DOI: 10.1101/2024.09.24.614743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 10/12/2024]
Abstract
Staphylococcus aureus is one of the most common pathogens isolated from the lungs of people with cystic fibrosis (CF), but little is known about its ability to colonize this niche. We performed a Tn-seq screen to identify genes necessary for S. aureus growth in media prepared from ex vivo CF sputum. We identified 19 genes that were required for growth in all sputum media tested and dozens more that were required for growth in at least one sputum medium. Depleted mutants of interest included insertions in many genes important for surviving metal starvation as well as the primary regulator of cysteine metabolism cymR . To investigate the mechanisms by which these genes contribute to S. aureus growth in sputum, we quantified low-molecular-weight thiols, nutrient transition metals, and the host metal-sequestration protein calprotectin in sputum from 11 individuals with CF. In all samples, the abundance of calprotectin exceeded nutrient metal concentration, explaining the S. aureus requirement for metal-starvation genes. Further, all samples contain potentially toxic quantities of cysteine and sufficient glutathione to satisfy the organic sulfur requirements of S. aureus . Deletion of the cysteine importer genes tcyA and tcyP in the Δ cymR background restored growth to wild-type levels in CF sputum, suggesting that the mechanism by which cymR is required for growth in sputum is to prevent uncontrolled import of cysteine or cystine from this environment. Overall, this work demonstrates that calprotectin and cysteine limit S. aureus growth in CF sputum. IMPORTANCE Staphylococcus aureus is a major cause of lung infections in people with cystic fibrosis (CF). This work identifies genes required for S. aureus growth in this niche, which represent potential targets for anti-Staphylococcal treatments. We show that genes involved in surviving metal starvation are required for growth in CF sputum. We also found that the primary regulator of cysteine metabolism, CymR, plays a critical role in preventing cysteine intoxication during growth in CF sputum. To support these models, we analyzed sputum from 11 individuals with CF to determine concentrations of calprotectin, nutrient metals, and low-molecular-weight thiols, which have not previously been quantified together in the same samples.
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Affiliation(s)
- Lauren M. Shull
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Daniel J. Wolter
- Department of Pediatrics, University of Washington School of Medicine, Seattle, Washington, USA
| | - Dillon E. Kunkle
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Katherine A. Legg
- Department of Chemistry, Indiana University, Bloomington, Indiana, USA
| | - David P. Giedroc
- Department of Chemistry, Indiana University, Bloomington, Indiana, USA
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana, USA
| | - Eric P. Skaar
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
| | - Lucas R. Hoffman
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, USA
- Department of Pediatrics, University of Washington School of Medicine, Seattle, Washington, USA
| | - Michelle L. Reniere
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, USA
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Su Z, Xu D, Hu X, Zhu W, Kong L, Qian Z, Mei J, Ma R, Shang X, Fan W, Zhu C. Biodegradable oxygen-evolving metalloantibiotics for spatiotemporal sono-metalloimmunotherapy against orthopaedic biofilm infections. Nat Commun 2024; 15:8058. [PMID: 39277594 PMCID: PMC11401848 DOI: 10.1038/s41467-024-52489-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Accepted: 09/10/2024] [Indexed: 09/17/2024] Open
Abstract
Pathogen-host competition for manganese and intricate immunostimulatory pathways severely attenuates the efficacy of antibacterial immunotherapy against biofilm infections associated with orthopaedic implants. Herein, we introduce a spatiotemporal sono-metalloimmunotherapy (SMIT) strategy aimed at efficient biofilm ablation by custom design of ingenious biomimetic metal-organic framework (PCN-224)-coated MnO2-hydrangea nanoparticles (MnPM) as a metalloantibiotic. Upon reaching the acidic H2O2-enriched biofilm microenvironment, MnPM can convert abundant H2O2 into oxygen, which is conducive to significantly enhancing the efficacy of ultrasound (US)-triggered sonodynamic therapy (SDT), thereby exposing bacteria-associated antigens (BAAs). Moreover, MnPM disrupts bacterial homeostasis, further killing more bacteria. Then, the Mn ions released from the degraded MnO2 can recharge immune cells to enhance the cGAS-STING signaling pathway sensing of BAAs, further boosting the immune response and suppressing biofilm growth via biofilm-specific T cell responses. Following US withdrawal, the sustained oxygenation promotes the survival and migration of fibroblasts, stimulates the expression of angiogenic growth factors and angiogenesis, and neutralizes excessive inflammation. Our findings highlight that MnPM may act as an immune costimulatory metalloantibiotic to regulate the cGAS-STING signaling pathway, presenting a promising alternative to antibiotics for orthopaedic biofilm infection treatment and pro-tissue repair.
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Affiliation(s)
- Zheng Su
- Department of Orthopedics, Centre for Leading Medicine and Advanced Technologies of IHM, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230001, China.
| | - Dongdong Xu
- Department of Orthopedics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450000, PR China
| | - Xianli Hu
- Department of Orthopedics, Centre for Leading Medicine and Advanced Technologies of IHM, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230001, China
| | - Wanbo Zhu
- Department of Orthopaedics, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai Jiao Tong University, Shanghai, 200233, PR China.
| | - Lingtong Kong
- Department of Orthopedics, Changhai Hospital of Shanghai, Shanghai, 200433, China
| | - Zhengzheng Qian
- State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, Center of Advanced Pharmaceuticals and Biomaterials, China Pharmaceutical University, Nanjing, 211198, China
| | - Jiawei Mei
- Department of Orthopedics, Centre for Leading Medicine and Advanced Technologies of IHM, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230001, China
| | - Ruixiang Ma
- Department of Orthopedics, Centre for Leading Medicine and Advanced Technologies of IHM, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230001, China
| | - Xifu Shang
- Department of Orthopedics, Centre for Leading Medicine and Advanced Technologies of IHM, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230001, China
| | - Wenpei Fan
- State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, Center of Advanced Pharmaceuticals and Biomaterials, China Pharmaceutical University, Nanjing, 211198, China.
| | - Chen Zhu
- Department of Orthopedics, Centre for Leading Medicine and Advanced Technologies of IHM, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230001, China.
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Peng W, Xu Y, Yin Y, Xie J, Ma R, Song G, Zhang Z, Quan Q, Jiang Q, Li M, Li B. Biological characteristics of manganese transporter MntP in Klebsiella pneumoniae. mSphere 2024; 9:e0037724. [PMID: 38888334 PMCID: PMC11288033 DOI: 10.1128/msphere.00377-24] [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: 05/05/2024] [Accepted: 05/29/2024] [Indexed: 06/20/2024] Open
Abstract
Klebsiella pneumoniae is an important opportunistic pathogen that causes a variety of infections. It is critical for bacteria to maintain metal homeostasis during infection. By using an isogenic mntP deletion mutant of K. pneumoniae strain NTUH-K2044, we found that MntP was a manganese efflux pump. Manganese increased the tolerance to oxidative stress, and oxidative stress could increase the intracellular manganese concentration. In oxidative stress, the mntP deletion mutant exhibited significantly higher sensitivity to manganese. Furthermore, iron could increase the tolerance of the mntP deletion mutant to manganese. Inductively coupled plasma mass spectrometry analysis revealed that the mntP deletion mutant had higher intracellular manganese and iron concentrations than wild-type and complementary strains. These findings suggested that iron could increase manganese tolerance in K. pneumoniae. This work elucidated the role of MntP in manganese detoxification and Mn/Fe homeostasis in K. pneumoniae.IMPORTANCEMetal homeostasis plays an important role during the process of bacterial infection. Herein, we revealed that MntP was involved in intracellular manganese homeostasis. Manganese promoted resistance to oxidative stress in Klebsiella pneumoniae. Furthermore, we demonstrated that the mntP deletion mutant exhibited significantly lower survival under manganese and H2O2 conditions. Oxidative stress increased the intracellular manganese content of the mntP deletion mutant. MntP played a critical role in maintaining intracellular manganese and iron concentrations. MntP contributed to manganese detoxification and Mn/Fe homeostasis in K. pneumoniae.
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Affiliation(s)
- Wei Peng
- School of Basic Medicine, Hubei University of Medicine, Shiyan, Hubei, China
- Biomedical Research Institute, Hubei University of Medicine, Shiyan, Hubei, China
| | - Yafei Xu
- School of Basic Medicine, Hubei University of Medicine, Shiyan, Hubei, China
| | - Yilin Yin
- School of Basic Medicine, Hubei University of Medicine, Shiyan, Hubei, China
| | - Jichen Xie
- School of Basic Medicine, Hubei University of Medicine, Shiyan, Hubei, China
| | - Renhui Ma
- School of Basic Medicine, Hubei University of Medicine, Shiyan, Hubei, China
| | - Guoyuan Song
- School of Basic Medicine, Hubei University of Medicine, Shiyan, Hubei, China
| | - Zhiqiang Zhang
- School of Basic Medicine, Hubei University of Medicine, Shiyan, Hubei, China
| | - Qiuhang Quan
- School of Basic Medicine, Hubei University of Medicine, Shiyan, Hubei, China
| | - Qinggen Jiang
- School of Basic Medicine, Hubei University of Medicine, Shiyan, Hubei, China
| | - Moran Li
- School of Basic Medicine, Hubei University of Medicine, Shiyan, Hubei, China
| | - Bei Li
- School of Basic Medicine, Hubei University of Medicine, Shiyan, Hubei, China
- Biomedical Research Institute, Hubei University of Medicine, Shiyan, Hubei, China
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Reyes Ruiz VM, Freiberg JA, Weiss A, Green ER, Jobson ME, Felton E, Shaw LN, Chazin WJ, Skaar EP. Coordinated adaptation of Staphylococcus aureus to calprotectin-dependent metal sequestration. mBio 2024; 15:e0138924. [PMID: 38920392 PMCID: PMC11253595 DOI: 10.1128/mbio.01389-24] [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: 05/07/2024] [Accepted: 05/21/2024] [Indexed: 06/27/2024] Open
Abstract
The host protein calprotectin inhibits the growth of a variety of bacterial pathogens through metal sequestration in a process known as "nutritional immunity." Staphylococcus aureus growth is inhibited by calprotectin in vitro, and calprotectin is localized in vivo to staphylococcal abscesses during infection. However, the staphylococcal adaptations that provide defense against nutritional immunity and the role of metal-responsive regulators are not fully characterized. In this work, we define the transcriptional response of S. aureus and the role of the metal-responsive regulators, Zur, Fur, and MntR, in response to metal limitation by calprotectin exposure. Additionally, we identified genes affecting the fitness of S. aureus during metal limitation through a Transposon sequencing (Tn-seq) approach. Loss of function mutations in clpP, which encodes a proteolytic subunit of the ATP-dependent Clp protease, demonstrate reduced fitness of S. aureus to the presence of calprotectin. ClpP contributes to pathogenesis in vivo in a calprotectin-dependent manner. These studies establish a critical role for ClpP to combat metal limitation by calprotectin and reveal the genes required for S. aureus to outcompete the host for metals. IMPORTANCE Staphylococcus aureus is a leading cause of skin and soft tissue infections, bloodstream infections, and endocarditis. Antibiotic treatment failures during S. aureus infections are increasingly prevalent, highlighting the need for novel antimicrobial agents. Metal chelator-based therapeutics have tremendous potential as antimicrobials due to the strict requirement for nutrient metals exhibited by bacterial pathogens. The high-affinity transition metal-binding properties of calprotectin represents a potential therapeutic strategy that functions through metal chelation. Our studies provide a foundation to define mechanisms by which S. aureus combats nutritional immunity and may be useful for the development of novel therapeutics to counter the ability of S. aureus to survive in a metal-limited environment.
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Affiliation(s)
- Valeria M. Reyes Ruiz
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Jeffrey A. Freiberg
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Division of Infectious Diseases, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Andy Weiss
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Erin R. Green
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Mary-Elizabeth Jobson
- Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, Florida, USA
| | - Emily Felton
- Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, Florida, USA
| | - Lindsey N. Shaw
- Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, Florida, USA
| | - Walter J. Chazin
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, USA
| | - Eric P. Skaar
- Department of Pathology, Microbiology, and 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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Sachla AJ, Soni V, Piñeros M, Luo Y, Im JJ, Rhee KY, Helmann JD. The Bacillus subtilis yqgC-sodA operon protects magnesium-dependent enzymes by supporting manganese efflux. J Bacteriol 2024; 206:e0005224. [PMID: 38819154 PMCID: PMC11332163 DOI: 10.1128/jb.00052-24] [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: 02/13/2024] [Accepted: 05/08/2024] [Indexed: 06/01/2024] Open
Abstract
Microbes encounter a myriad of stresses during their life cycle. Dysregulation of metal ion homeostasis is increasingly recognized as a key factor in host-microbe interactions. Bacterial metal ion homeostasis is tightly regulated by dedicated metalloregulators that control uptake, sequestration, trafficking, and efflux. Here, we demonstrate that deletion of the Bacillus subtilis yqgC-sodA (YS) complex operon, but not deletion of the individual genes, causes hypersensitivity to manganese (Mn). YqgC is an integral membrane protein of unknown function, and SodA is a Mn-dependent superoxide dismutase (MnSOD). The YS strain has reduced expression of two Mn efflux proteins, MneP and MneS, consistent with the observed Mn sensitivity. The YS strain accumulated high levels of Mn, had increased reactive radical species (RRS), and had broad metabolic alterations that can be partially explained by the inhibition of Mg-dependent enzymes. Although the YS operon deletion strain and an efflux-deficient mneP mneS double mutant both accumulate Mn and have similar metabolic perturbations, they also display phenotypic differences. Several mutations that suppressed Mn intoxication of the mneP mneS efflux mutant did not benefit the YS mutant. Further, Mn intoxication in the YS mutant, but not the mneP mneS strain, was alleviated by expression of Mg-dependent, chorismate-utilizing enzymes of the menaquinone, siderophore, and tryptophan (MST) family. Therefore, despite their phenotypic similarities, the Mn sensitivity in the mneP mneS and the YS deletion mutants results from distinct enzymatic vulnerabilities.IMPORTANCEBacteria require multiple trace metal ions for survival. Metal homeostasis relies on the tightly regulated expression of metal uptake, storage, and efflux proteins. Metal intoxication occurs when metal homeostasis is perturbed and often results from enzyme mis-metalation. In Bacillus subtilis, Mn-dependent superoxide dismutase (MnSOD) is the most abundant Mn-containing protein and is important for oxidative stress resistance. Here, we report novel roles for MnSOD and a co-regulated membrane protein, YqgC, in Mn homeostasis. Loss of both MnSOD and YqgC (but not the individual proteins) prevents the efficient expression of Mn efflux proteins and leads to a large-scale perturbation of the metabolome due to inhibition of Mg-dependent enzymes, including key chorismate-utilizing MST (menaquinone, siderophore, and tryptophan) family enzymes.
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Affiliation(s)
- Ankita J. Sachla
- Department of Microbiology, Cornell University, Ithaca, New York, USA
| | - Vijay Soni
- Division of Infectious Diseases, Weill Department of Medicine, Weill Cornell Medicine, New York, New York, USA
| | - Miguel Piñeros
- School of Integrative Plant Sciences, Plant Biology Section, Cornell University, Ithaca, New York, USA
- Robert W. Holley Center for Agriculture and Health, USDA-ARS, Ithaca, New York, USA
| | - Yuanchan Luo
- Department of Microbiology, Cornell University, Ithaca, New York, USA
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Janice J. Im
- Department of Microbiology, Cornell University, Ithaca, New York, USA
| | - Kyu Y. Rhee
- Division of Infectious Diseases, Weill Department of Medicine, Weill Cornell Medicine, New York, New York, USA
| | - John D. Helmann
- Department of Microbiology, Cornell University, Ithaca, New York, USA
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Mohite SV, Sharma KK. Gut microbial metalloproteins and its role in xenobiotics degradation and ROS scavenging. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2024; 141:495-538. [PMID: 38960484 DOI: 10.1016/bs.apcsb.2024.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/05/2024]
Abstract
The gut microbial metalloenzymes play an important role in maintaining the balance between gut microbial ecosystem, human physiologically processes and immune system. The metals coordinated into active site contribute in various detoxification and defense strategies to avoid unfavourable environment and ensure bacterial survival in human gut. Metallo-β-lactamase is a potent degrader of antibiotics present in periplasmic space of both commensals and pathogenic bacteria. The resistance to anti-microbial agents developed in this enzyme is one of the global threats for human health. The organophosphorus eliminator, organophosphorus hydrolases have evolved over a course of time to hydrolyze toxic organophosphorus compounds and decrease its effect on human health. Further, the redox stress responders namely superoxide dismutase and catalase are key metalloenzymes in reducing both endogenous and exogenous oxidative stress. They hold a great importance for pathogens as they contribute in pathogenesis in human gut along with reduction of oxidative stress. The in-silico study on these enzymes reveals the importance of point mutation for the evolution of these enzymes in order to enhance their enzyme activity and stability. Various mutation studies were conducted to investigate the catalytic activity of these enzymes. By using the "directed evolution" method, the enzymes involved in detoxification and defense system can be engineered to produce new variants with enhance catalytic features, which may be used to predict the severity due to multi-drug resistance and degradation pattern of organophosphorus compounds in human gut.
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Affiliation(s)
- Shreya Vishwas Mohite
- Laboratory of Enzymology and Gut Microbiology, Department of Microbiology, Maharshi Dayanand University, Rohtak, Haryana, India
| | - Krishna Kant Sharma
- Laboratory of Enzymology and Gut Microbiology, Department of Microbiology, Maharshi Dayanand University, Rohtak, Haryana, India.
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Lê-Bury P, Echenique-Rivera H, Pizarro-Cerdá J, Dussurget O. Determinants of bacterial survival and proliferation in blood. FEMS Microbiol Rev 2024; 48:fuae013. [PMID: 38734892 PMCID: PMC11163986 DOI: 10.1093/femsre/fuae013] [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: 11/06/2023] [Revised: 04/29/2024] [Accepted: 05/10/2024] [Indexed: 05/13/2024] Open
Abstract
Bloodstream infection is a major public health concern associated with high mortality and high healthcare costs worldwide. Bacteremia can trigger fatal sepsis whose prevention, diagnosis, and management have been recognized as a global health priority by the World Health Organization. Additionally, infection control is increasingly threatened by antimicrobial resistance, which is the focus of global action plans in the framework of a One Health response. In-depth knowledge of the infection process is needed to develop efficient preventive and therapeutic measures. The pathogenesis of bloodstream infection is a dynamic process resulting from the invasion of the vascular system by bacteria, which finely regulate their metabolic pathways and virulence factors to overcome the blood immune defenses and proliferate. In this review, we highlight our current understanding of determinants of bacterial survival and proliferation in the bloodstream and discuss their interactions with the molecular and cellular components of blood.
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Affiliation(s)
- Pierre Lê-Bury
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Yersinia Research Unit, 28 rue du Dr Roux, 75015 Paris, France
- Université Paris-Saclay, Inserm, CEA, Center for Immunology of Viral, Autoimmune, Hematological and Bacterial Diseases (IMVA-HB/IDMIT), 18 route du Panorama, 92260 Fontenay-aux-Roses, France
| | - Hebert Echenique-Rivera
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Yersinia Research Unit, 28 rue du Dr Roux, 75015 Paris, France
| | - Javier Pizarro-Cerdá
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Yersinia Research Unit, 28 rue du Dr Roux, 75015 Paris, France
- Institut Pasteur, Université Paris Cité, Yersinia National Reference Laboratory, WHO Collaborating Research & Reference Centre for Plague FRA-146, 28 rue du Dr Roux, 75015 Paris, France
| | - Olivier Dussurget
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Yersinia Research Unit, 28 rue du Dr Roux, 75015 Paris, France
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Sachla AJ, Soni V, Piñeros M, Luo Y, Im JJ, Rhee KY, Helmann JD. The Bacillus subtilis yqgC-sodA operon protects magnesium-dependent enzymes by supporting manganese efflux. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.14.580342. [PMID: 38405924 PMCID: PMC10888875 DOI: 10.1101/2024.02.14.580342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Microbes encounter a myriad of stresses during their life cycle. Dysregulation of metal ion homeostasis is increasingly recognized as a key factor in host-microbe interactions. Bacterial metal ion homeostasis is tightly regulated by dedicated metalloregulators that control uptake, sequestration, trafficking, and efflux. Here, we demonstrate that deletion of the Bacillus subtilis yqgC-sodA (YS) complex operon, but not deletion of the individual genes, causes hypersensitivity to manganese (Mn). YqgC is an integral membrane protein of unknown function and SodA is a Mn-dependent superoxide dismutase (MnSOD). The YS strain has reduced expression of two Mn efflux proteins, MneP and MneS, consistent with the observed Mn sensitivity. The YS strain accumulated high levels of Mn, had increased reactive radical species (RRS), and had broad metabolic alterations that can be partially explained by the inhibition of Mg-dependent enzymes. Although the YS operon deletion strain and an efflux-deficient mneP mneS double mutant both accumulate Mn and have similar metabolic perturbations they also display phenotypic differences. Several mutations that suppressed Mn intoxication of the mneP mneS efflux mutant did not benefit the YS mutant. Further, Mn intoxication in the YS mutant, but not the mneP mneS strain, was alleviated by expression of Mg-dependent, chorismate-utilizing enzymes of the menaquinone, siderophore, and tryptophan (MST) family. Therefore, despite their phenotypic similarities, the Mn sensitivity in the mneP mneS and the yqgC-sodA deletion mutants results from distinct enzymatic vulnerabilities.
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Affiliation(s)
- Ankita J. Sachla
- Cornell University, Department of Microbiology, Ithaca, NY, 14853-8101, USA
| | - Vijay Soni
- Division of Infectious Diseases, Weill Department of Medicine, Weill Cornell Medicine, New York, NY 10065, USA
| | - Miguel Piñeros
- School of Integrative Plant Sciences, Plant Biology Section, Cornell University, Ithaca, NY 14853, USA
- Robert W. Holley Center for Agriculture and Health, USDA-ARS, Ithaca, NY 14853, USA
| | - Yuanchan Luo
- Cornell University, Department of Microbiology, Ithaca, NY, 14853-8101, USA
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Janice J. Im
- Cornell University, Department of Microbiology, Ithaca, NY, 14853-8101, USA
| | - Kyu Y. Rhee
- Division of Infectious Diseases, Weill Department of Medicine, Weill Cornell Medicine, New York, NY 10065, USA
| | - John D. Helmann
- Cornell University, Department of Microbiology, Ithaca, NY, 14853-8101, USA
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10
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Chen Q, Guo F, Huang L, Wang M, Shi C, Zhang S, Yao Y, Wang M, Zhu D, Jia R, Chen S, Zhao X, Yang Q, Wu Y, Zhang S, Tian B, Huang J, Ou X, Gao Q, Sun D, Zhang L, Yu Y, He Y, Wu Z, Götz F, Cheng A, Liu M. Functional characterization of a TerC family protein of Riemerella anatipestifer in manganese detoxification and virulence. Appl Environ Microbiol 2024; 90:e0135023. [PMID: 38084999 PMCID: PMC10807442 DOI: 10.1128/aem.01350-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 11/02/2023] [Indexed: 12/20/2023] Open
Abstract
Manganese (Mn) is an essential element for bacteria, but the overload of manganese is toxic. In a previous study, we showed that the cation diffusion facilitator protein MetA and the resistance-nodulation-division efflux pump MetB are responsible for Mn efflux in the bacterial pathogen Riemerella anatipestifer CH-1. However, whether this bacterium encodes additional manganese efflux proteins is unclear. In this study, we show that R. anatipestifer CH-1 encodes a tellurium resistance C (TerC) family protein with low similarity to other characterized TerC family proteins. Compared to the wild type (WT), the terC mutant of R. anatipestifer CH-1 (∆terC) is sensitive to Mn(II) intoxication. The ability of TerC to export manganese is higher than that of MetB but lower than that of MetA. Consistently, terC deletion (∆terC) led to intracellular accumulation of Mn2+ under excess manganese conditions. Further study showed that ∆terC was more sensitive than the WT to the oxidant hypoclorite but not to hydrogen peroxide. Mutagenesis studies showed that the mutant at amino acid sites of Glu116 (E116), Asp122 (D122), Glu245 (E245) Asp248 (D248), and Asp254 (D254) may be involved in the ability of TerC to export manganese. The transcription of terC was upregulated under excess manganese and downregulated under iron-limited conditions. However, this was not dependent on the manganese metabolism regulator MetR. In contrast to a strain lacking the manganese efflux pump MetA or MetB, the terC mutant is attenuated in virulence in a duckling model of infection due to increased sensitivity to duck serum. Finally, comparative analysis showed that homologs of TerC are distributed across the bacterial kingdom, suggesting that TerC exerts a conserved manganese efflux function.IMPORTANCERiemerella anatipestifer is a notorious bacterial pathogen of ducks and other birds. In R. anatipestifer, the genes involved in manganese efflux have not been completely identified, although MetA and MetB have been identified as two manganese exporters. Additionally, the function of TerC family proteins in manganese efflux is controversial. Here, we demonstrated that a TerC family protein helps prevent Mn(II) intoxication in R. anatipestifer and that the ability of TerC to export manganese is intermediate compared to that of MetA and MetB. Sequence analysis and mutagenesis studies showed that the conserved key amino sites of TerC are Glu116, Asp122, Glu245, Asp248, and Asp254. The transcription of terC was regulated by manganese excess and iron limitation. Finally, we show that TerC plays a role in the virulence of R. anatipestifer due to the increased sensitivity to duck serum, rather than the increased sensitivity to manganese. Taken together, these results expand our understanding of manganese efflux and the pathogenic mechanisms of R. anatipestifer.
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Affiliation(s)
- Qinyuan Chen
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Fang Guo
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Li Huang
- College of Animal Husbandry and Veterinary Medicine, Southwest Minzu University, Chengdu, China
| | - Mengying Wang
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Chunfeng Shi
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Shutong Zhang
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Yizhou Yao
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Mingshu Wang
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Dekang Zhu
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Renyong Jia
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Shun Chen
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Xinxin Zhao
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Qiao Yang
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Ying Wu
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Shaqiu Zhang
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Bin Tian
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Juan Huang
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Xumin Ou
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Qun Gao
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Di Sun
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Ling Zhang
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Yanling Yu
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Yu He
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Zhen Wu
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Friedrich Götz
- Microbial Genetics, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany
| | - Anchun Cheng
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Mafeng Liu
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
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11
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Huang L, Guo F, Li X, Wang M, Zhu D, Wang M, Jia R, Chen S, Zhao X, Zhang S, Gao Q, Yang Q, Wu Y, Huang J, Tian B, Ou X, Sun D, Mao S, Zhang L, Yu Y, Götz F, Cheng A, Liu M. Functional characterization of two TolC in the resistance to drugs and metals and in the virulence of Riemerella anatipestifer. Appl Environ Microbiol 2023; 89:e0130823. [PMID: 38038982 PMCID: PMC10734528 DOI: 10.1128/aem.01308-23] [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: 07/29/2023] [Accepted: 10/18/2023] [Indexed: 12/02/2023] Open
Abstract
IMPORTANCE Riemerella anatipestifer (RA) is a notorious duck pathogen, characterized by a multitude of serotypes that exhibit no cross-reaction with one another. Moreover, RA is resistant to various antibacterial agents. Consequently, understanding the mechanisms behind resistance and identifying potential targets for drug development have become pressing needs. In this study, we show that the two TolC proteins play a role in the resistance to different drugs and metals and in the virulence. The results suggest that TolCA has a wider range of efflux substrates than TolCB. Except for gentamicin, neither TolCA nor TolCB was involved in the efflux of the other tested antibiotics. Strikingly, TolCA but not TolCB enhanced the frequency of resistance-conferring mutations. Moreover, TolCA was involved in RA virulence. Given its conservation in RA, TolCA has potential as a drug target for the development of therapeutics against RA infections.
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Affiliation(s)
- Li Huang
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- College of Animal Husbandry and Veterinary Medicine, Southwest Minzu University, Chengdu, China
| | - Fang Guo
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Xiao Li
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Mengying Wang
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Dekang Zhu
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Mingshu Wang
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Renyong Jia
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Shun Chen
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Xinxin Zhao
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Shaqiu Zhang
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Qun Gao
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Qiao Yang
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Ying Wu
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Juan Huang
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Bin Tian
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Xumin Ou
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Di Sun
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Sai Mao
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Ling Zhang
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - YanLing Yu
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Friedrich Götz
- Microbial Genetics, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany
| | - Anchun Cheng
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Mafeng Liu
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
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12
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Hong Y, Mackenzie ES, Firth SJ, Bolton JRF, Stewart LJ, Waldron KJ, Djoko KY. Mis-regulation of Zn and Mn homeostasis is a key phenotype of Cu stress in Streptococcus pyogenes. Metallomics 2023; 15:mfad064. [PMID: 37849243 PMCID: PMC10644519 DOI: 10.1093/mtomcs/mfad064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Accepted: 10/16/2023] [Indexed: 10/19/2023]
Abstract
All bacteria possess homeostastic mechanisms that control the availability of micronutrient metals within the cell. Cross-talks between different metal homeostasis pathways within the same bacterial organism have been reported widely. In addition, there have been previous suggestions that some metal uptake transporters can promote adventitious uptake of the wrong metal. This work describes the cross-talk between Cu and the Zn and Mn homeostasis pathways in Group A Streptococcus (GAS). Using a ∆copA mutant strain that lacks the primary Cu efflux pump and thus traps excess Cu in the cytoplasm, we show that growth in the presence of supplemental Cu promotes downregulation of genes that contribute to Zn or Mn uptake. This effect is not associated with changes in cellular Zn or Mn levels. Co-supplementation of the culture medium with Zn or, to a lesser extent, Mn alleviates key Cu stress phenotypes, namely bacterial growth and secretion of the fermentation end-product lactate. However, neither co-supplemental Zn nor Mn influences cellular Cu levels or Cu availability in Cu-stressed cells. In addition, we provide evidence that the Zn or Mn uptake transporters in GAS do not promote Cu uptake. Together, the results from this study strengthen and extend our previous proposal that mis-regulation of Zn and Mn homeostasis is a key phenotype of Cu stress in GAS.
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Affiliation(s)
- YoungJin Hong
- Department of Biosciences, Durham University, Durham DH1 3LE, UK
| | - Eilidh S Mackenzie
- Biosciences Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Samantha J Firth
- Department of Biosciences, Durham University, Durham DH1 3LE, UK
| | - Jack R F Bolton
- Department of Biosciences, Durham University, Durham DH1 3LE, UK
| | - Louisa J Stewart
- Department of Biosciences, Durham University, Durham DH1 3LE, UK
| | - Kevin J Waldron
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106 Warsaw, Poland
- Previous affiliation: Biosciences Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Karrera Y Djoko
- Department of Biosciences, Durham University, Durham DH1 3LE, UK
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13
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Kunkle DE, Skaar EP. Moving metals: How microbes deliver metal cofactors to metalloproteins. Mol Microbiol 2023; 120:547-554. [PMID: 37408317 PMCID: PMC10592388 DOI: 10.1111/mmi.15117] [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: 02/13/2023] [Revised: 06/08/2023] [Accepted: 06/13/2023] [Indexed: 07/07/2023]
Abstract
First row d-block metal ions serve as vital cofactors for numerous essential enzymes and are therefore required nutrients for all forms of life. Despite this requirement, excess free transition metals are toxic. Free metal ions participate in the production of noxious reactive oxygen species and mis-metalate metalloproteins, rendering enzymes catalytically inactive. Thus, bacteria require systems to ensure metalloproteins are properly loaded with cognate metal ions to maintain protein function, while avoiding metal-mediated cellular toxicity. In this perspective we summarize the current mechanistic understanding of bacterial metallocenter maturation with specific emphasis on metallochaperones; a group of specialized proteins that both shield metal ions from inadvertent reactions and distribute them to cognate target metalloproteins. We highlight several recent advances in the field that have implicated new classes of proteins in the distribution of metal ions within bacterial proteins, while speculating on the future of the field of bacterial metallobiology.
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Affiliation(s)
- Dillon E. Kunkle
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Eric P. Skaar
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, TN, USA
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14
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Guo F, Wang M, Huang M, Jiang Y, Gao Q, Zhu D, Wang M, Jia R, Chen S, Zhao X, Yang Q, Wu Y, Zhang S, Huang J, Tian B, Ou X, Mao S, Sun D, Cheng A, Liu M. Manganese Efflux Achieved by MetA and MetB Affects Oxidative Stress Resistance and Iron Homeostasis in Riemerella anatipestifer. Appl Environ Microbiol 2023; 89:e0183522. [PMID: 36815770 PMCID: PMC10057955 DOI: 10.1128/aem.01835-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 01/29/2023] [Indexed: 02/24/2023] Open
Abstract
In bacteria, manganese homeostasis is controlled by import, regulation, and efflux. Here, we identified 2 Mn exporters, MetA and MetB (manganese efflux transporters A and B), in Riemerella anatipestifer CH-1, encoding a putative cation diffusion facilitator (CDF) protein and putative resistance-nodulation-division (RND) efflux pump, respectively. Compared with the wild type (WT), ΔmetA, ΔmetB, and ΔmetAΔmetB exhibited sensitivity to manganese, since they accumulated more intracellular Mn2+ than the WT under excess manganese conditions, while the amount of iron in the mutants was decreased. Moreover, ΔmetA, ΔmetB, and ΔmetAΔmetB were more sensitive to the oxidant NaOCl than the WT. Further study showed that supplementation with iron sources could alleviate manganese toxicity and that excess manganese inhibited bacterial cell division. RNA-Seq showed that manganese stress resulted in the perturbation of iron metabolism genes, further demonstrating that manganese efflux is critical for iron homeostasis. metA transcription was upregulated under excess manganese but was not activated by MetR, a DtxR family protein, although MetR was also involved in manganese detoxification, while metB transcription was downregulated under iron depletion conditions and in fur mutants. Finally, homologues of MetA and MetB were found to be mainly distributed in members of Flavobacteriaceae. Specifically, MetB represents a novel manganese exporter in Gram-negative bacteria. IMPORTANCE Manganese is required for the function of many proteins in bacteria, but in excess, manganese can mediate toxicity. Therefore, the intracellular levels of manganese must be tightly controlled. Manganese efflux transporters have been characterized in some other bacteria; however, their homologues could not be found in the genome of Riemerella anatipestifer through sequence comparison. This indicated that other types of manganese efflux transporters likely exist. In this study, we characterized 2 transporters, MetA and MetB, that mediate manganese efflux in R. anatipestifer in response to manganese overload. MetA encodes a putative cation diffusion facilitator (CDF) protein, which has been characterized as a manganese transporter in other bacteria, while this is the first observation of a putative resistance-nodulation-division (RND) transporter contributing to manganese export in Gram-negative bacteria. In addition, the mechanism of manganese toxicity was studied by observing morphological changes and by transcriptome sequencing. Taken together, these results are important for expanding our understanding of manganese transporters and revealing the mechanism of manganese toxicity.
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Affiliation(s)
- Fang Guo
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, People’s Republic of China
| | - Mengying Wang
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, People’s Republic of China
| | - Mi Huang
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, People’s Republic of China
| | - Yin Jiang
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, People’s Republic of China
| | - Qun Gao
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, People’s Republic of China
| | - Dekang Zhu
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, People’s Republic of China
| | - Mingshu Wang
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, People’s Republic of China
| | - Renyong Jia
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, People’s Republic of China
| | - Shun Chen
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, People’s Republic of China
| | - Xinxin Zhao
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, People’s Republic of China
| | - Qiao Yang
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, People’s Republic of China
| | - Ying Wu
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, People’s Republic of China
| | - Shaqiu Zhang
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, People’s Republic of China
| | - Juan Huang
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, People’s Republic of China
| | - Bin Tian
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, People’s Republic of China
| | - Xumin Ou
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, People’s Republic of China
| | - Sai Mao
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, People’s Republic of China
| | - Di Sun
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, People’s Republic of China
| | - Anchun Cheng
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, People’s Republic of China
| | - Mafeng Liu
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, People’s Republic of China
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15
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Ha N, Lee EJ. Manganese Transporter Proteins in Salmonella enterica serovar Typhimurium. J Microbiol 2023; 61:289-296. [PMID: 36862278 DOI: 10.1007/s12275-023-00027-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 02/08/2023] [Accepted: 02/08/2023] [Indexed: 03/03/2023]
Abstract
The metal cofactors are essential for the function of many enzymes. The host restricts the metal acquisition of pathogens for their immunity and the pathogens have evolved many ways to obtain metal ions for their survival and growth. Salmonella enterica serovar Typhimurium also needs several metal cofactors for its survival, and manganese has been found to contribute to Salmonella pathogenesis. Manganese helps Salmonella withstand oxidative and nitrosative stresses. In addition, manganese affects glycolysis and the reductive TCA, which leads to the inhibition of energetic and biosynthetic metabolism. Therefore, manganese homeostasis is crucial for full virulence of Salmonella. Here, we summarize the current information about three importers and two exporters of manganese that have been identified in Salmonella. MntH, SitABCD, and ZupT have been shown to participate in manganese uptake. mntH and sitABCD are upregulated by low manganese concentration, oxidative stress, and host NRAMP1 level. mntH also contains a Mn2+-dependent riboswitch in its 5' UTR. Regulation of zupT expression requires further investigation. MntP and YiiP have been identified as manganese efflux proteins. mntP is transcriptionally activated by MntR at high manganese levels and repressed its activity by MntS at low manganese levels. Regulation of yiiP requires further analysis, but it has been shown that yiiP expression is not dependent on MntS. Besides these five transporters, there might be additional transporters that need to be identified.
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Affiliation(s)
- Nakyeong Ha
- Department of Life Sciences, Korea University, Seoul, 02841, Republic of Korea
| | - Eun-Jin Lee
- Department of Life Sciences, Korea University, Seoul, 02841, Republic of Korea.
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16
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Čapek J, Večerek B. Why is manganese so valuable to bacterial pathogens? Front Cell Infect Microbiol 2023; 13:943390. [PMID: 36816586 PMCID: PMC9936198 DOI: 10.3389/fcimb.2023.943390] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 01/04/2023] [Indexed: 02/05/2023] Open
Abstract
Apart from oxygenic photosynthesis, the extent of manganese utilization in bacteria varies from species to species and also appears to depend on external conditions. This observation is in striking contrast to iron, which is similar to manganese but essential for the vast majority of bacteria. To adequately explain the role of manganese in pathogens, we first present in this review that the accumulation of molecular oxygen in the Earth's atmosphere was a key event that linked manganese utilization to iron utilization and put pressure on the use of manganese in general. We devote a large part of our contribution to explanation of how molecular oxygen interferes with iron so that it enhances oxidative stress in cells, and how bacteria have learned to control the concentration of free iron in the cytosol. The functioning of iron in the presence of molecular oxygen serves as a springboard for a fundamental understanding of why manganese is so valued by bacterial pathogens. The bulk of this review addresses how manganese can replace iron in enzymes. Redox-active enzymes must cope with the higher redox potential of manganese compared to iron. Therefore, specific manganese-dependent isoenzymes have evolved that either lower the redox potential of the bound metal or use a stronger oxidant. In contrast, redox-inactive enzymes can exchange the metal directly within the individual active site, so no isoenzymes are required. It appears that in the physiological context, only redox-inactive mononuclear or dinuclear enzymes are capable of replacing iron with manganese within the same active site. In both cases, cytosolic conditions play an important role in the selection of the metal used. In conclusion, we summarize both well-characterized and less-studied mechanisms of the tug-of-war for manganese between host and pathogen.
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Affiliation(s)
- Jan Čapek
- *Correspondence: Jan Čapek, ; Branislav Večerek,
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17
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Steingard CH, Pinochet-Barros A, Wendel BM, Helmann JD. Iron homeostasis in Bacillus subtilis relies on three differentially expressed efflux systems. MICROBIOLOGY (READING, ENGLAND) 2023; 169:001289. [PMID: 36748638 PMCID: PMC9993123 DOI: 10.1099/mic.0.001289] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
In Bacillus subtilis, iron homeostasis is maintained by the ferric uptake regulator (Fur) and manganese homeostasis relies on the manganese transport regulator (MntR). Both Fur and MntR function as bi-functional metalloregulators that repress import and activate metal ion efflux systems. The ferrous iron efflux ATPase, PfeT, is derepressed by hydrogen peroxide (H2O2) as sensed by PerR and induced by iron as sensed by Fur. Mutants lacking PfeT are sensitive to iron intoxication. Here, we show that mntR mutants are also iron-sensitive, largely due to decreased expression of the MntR-activated MneP and MneS cation diffusion facilitator (CDF) proteins previously defined for their role in Mn2+ export. The ability of MneP and MneS to export iron is apparent even when their expression is not induced by Mn2+. Our results demonstrate that PfeT, MneP and MneS each contribute to iron homeostasis, and a triple mutant lacking all three is more iron-sensitive than any single mutant. We further show that sensitivity to H2O2 does not correlate with iron sensitivity. For example, an mntR mutant is H2O2-sensitive due to elevated Mn(II) that increases PerR-mediated repression of peroxide resistance genes, and this repression is antagonized by elevated Fe2+ in an mntR pfeT mutant. Thus, H2O2-sensitivity reflects the relative levels of Mn2+ and Fe2+ as sensed by the PerR regulatory protein. These results underscore the complex interplay between manganese, iron and oxidative stress in B. subtilis.
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Affiliation(s)
- Caroline H Steingard
- Department of Microbiology, Cornell University, Ithaca, New York 14853-8101, USA
| | - Azul Pinochet-Barros
- Department of Microbiology, Cornell University, Ithaca, New York 14853-8101, USA
| | - Brian M Wendel
- Department of Microbiology, Cornell University, Ithaca, New York 14853-8101, USA
| | - John D Helmann
- Department of Microbiology, Cornell University, Ithaca, New York 14853-8101, USA
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18
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Dey S, Shahrear S, Afroj Zinnia M, Tajwar A, Islam ABMMK. Functional Annotation of Hypothetical Proteins From the Enterobacter cloacae B13 Strain and Its Association With Pathogenicity. Bioinform Biol Insights 2022; 16:11779322221115535. [PMID: 35958299 PMCID: PMC9358594 DOI: 10.1177/11779322221115535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 06/11/2022] [Indexed: 11/25/2022] Open
Abstract
Enterobacter cloacae B13 strain is a rod-shaped gram-negative bacterium that belongs to the Enterobacteriaceae family. It can cause respiratory and urinary tract infections, and is responsible for several outbreaks in hospitals. E. cloacae has become an important pathogen and an emerging global threat because of its opportunistic and multidrug resistant ability. However, little knowledge is present about a large portion of its proteins and functions. Therefore, functional annotation of the hypothetical proteins (HPs) can provide an improved understanding of this organism and its virulence activity. The workflow in the study included several bioinformatic tools which were utilized to characterize functions, family and domains, subcellular localization, physiochemical properties, and protein-protein interactions. The E. cloacae B13 strain has overall 604 HPs, among which 78 were functionally annotated with high confidence. Several proteins were identified as enzymes, regulatory, binding, and transmembrane proteins with essential functions. Furthermore, 23 HPs were predicted to be virulent factors. These virulent proteins are linked to pathogenesis with their contribution to biofilm formation, quorum sensing, 2-component signal transduction or secretion. Better knowledge about the HPs’ characteristics and functions will provide a greater overview of the proteome. Moreover, it will help against E. cloacae in neonatal intensive care unit (NICU) outbreaks and nosocomial infections.
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Affiliation(s)
- Supantha Dey
- Department of Genetic Engineering and Biotechnology, University of Dhaka, Dhaka, Bangladesh
| | - Sazzad Shahrear
- Department of Genetic Engineering and Biotechnology, University of Dhaka, Dhaka, Bangladesh
| | | | - Ahnaf Tajwar
- Department of Genetic Engineering and Biotechnology, University of Dhaka, Dhaka, Bangladesh
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19
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Stephens AC, Richardson AR. Recent developments in our understanding of the physiology and nitric oxide-resistance of Staphylococcus aureus. Adv Microb Physiol 2022; 81:111-135. [PMID: 36167441 DOI: 10.1016/bs.ampbs.2022.06.003] [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: 01/27/2023]
Abstract
Staphylococcus aureus is an important human pathogen causing a wide range of disease presentations. It harbors a vast array of virulence factors and drug-resistance determinants. All of these factors are coordinately regulated by a hand full of key transcriptional regulators. The regulation and expression of these factors are tightly intertwined with the metabolic state of the cell. Furthermore, alterations in central metabolism are also key to the ability of S. aureus to resist clearance by the host innate immune response, including nitric oxide (NO·) production. Given the fact that central metabolism directly influences virulence, drug resistance and immune tolerance in S. aureus, a better understanding of the metabolic capabilities of this pathogen is critical. This work highlights some of the major findings within the last five years surrounding S. aureus central metabolism, both organic and inorganic. These are also put in the context of the unique NO·-resistance associated with this pathogen as well as their contributions to virulence. The more we understand the intersection between central metabolism and virulence capabilities in S. aureus, the better the chances of developing novel therapeutics so desperately needed to treat this pathogen.
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Affiliation(s)
- Amelia C Stephens
- Department of Microbiology & Molecular Genetics, University of Pittsburgh, Pittsburgh, PA, United States
| | - Anthony R Richardson
- Department of Microbiology & Molecular Genetics, University of Pittsburgh, Pittsburgh, PA, United States.
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Abstract
Klebsiella pneumoniae is an opportunistic Gram-negative pathogen that is a leading cause of healthcare-associated infections, including pneumonia, urinary tract infections, and sepsis. Essential to the colonization and infection by K. pneumoniae is the acquisition of nutrients, such as the transition metal ion zinc. Zinc has crucial structural and catalytic roles in the proteome of all organisms. Nevertheless, in excess, it has the potential to mediate significant toxicity by dysregulating the homeostasis of other transition elements, disrupting enzymatic processes, and perturbing metalloprotein cofactor acquisition. Here, we sought to elucidate the zinc detoxification mechanisms of K. pneumoniae, which remain poorly defined. Using the representative K. pneumoniae AJ218 strain, we showed that the P-type ATPase, ZntA, which is upregulated in response to cellular zinc stress, was the primary zinc efflux pathway. Deletion of zntA rendered K. pneumoniae AJ218 highly susceptible to exogenous zinc stress and manifested as an impaired growth phenotype and increased cellular accumulation of the metal. Loss of zntA also increased sensitivity to cadmium stress, indicating a role for this efflux pathway in cadmium resistance. Disruption of zinc homeostasis in the K. pneumoniae AJ218 ΔzntA strain also impacted manganese and iron homeostasis and was associated with increased production of biofilm. Collectively, this work showed the critical role of ZntA in K. pneumoniae zinc tolerance and provided a foundation for further studies on zinc homeostasis and the future development of novel antimicrobials to target this pathway. IMPORTANCE Klebsiella pneumoniae is a leading cause of healthcare-associated infections, including pneumonia, urinary tract infections, and sepsis. Treatment of K. pneumoniae infections is becoming increasingly challenging due to high levels of antibiotic resistance and the rising prevalence of carbapenem-resistant, extended-spectrum β-lactamases producing strains. Zinc is essential to the colonization and infection by many bacterial pathogens but toxic in excess. This work described the first dissection of the pathways associated with resisting extracellular zinc stress in K. pneumoniae. This study revealed that the P-type ATPase ZntA was highly upregulated in response to exogenous zinc stress and played a major role in maintaining bacterial metal homeostasis. Knowledge of how this major bacterial pathogen resists zinc stress provided a foundation for antimicrobial development studies to target and abrogate their essential function.
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21
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MntP and YiiP Contribute to Manganese Efflux in Salmonella enterica Serovar Typhimurium under Conditions of Manganese Overload and Nitrosative Stress. Microbiol Spectr 2022; 10:e0131621. [PMID: 35019706 PMCID: PMC8754126 DOI: 10.1128/spectrum.01316-21] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
The divalent transition metal cation manganese is important for protein function, particularly under conditions of iron limitation, nitrosative stress, and oxidative stress, but can mediate substantial toxicity in excess. Salmonella enterica serovar Typhimurium possesses multiple manganese importers, but the pathways for manganese efflux remain poorly defined. The S. Typhimurium ATCC 14028s genome was analyzed for putative manganese export pathways, which identified a previously uncharacterized homologue of the Escherichia coli manganese exporter mntP, stm1834, and two cation diffusion facilitator family transporters, zitB (stm0758) and yiiP (stm4061). Manganese acquisition by S. Typhimurium has been shown to occur in response to nitric oxide, an important chemical mediator of the mammalian innate immune response. However, cellular manganese can rapidly return to prechallenge levels, strongly suggesting that one or more S. Typhimurium exporters may contribute to this process. Here, we report that mntP and yiiP contribute to manganese resistance and export in S. Typhimurium. YiiP, also known as FieF, has previously been associated with zinc and iron transport, although its physiological role remains ambiguous due to a lack of zinc-sensitive phenotypes in yiiP mutant strains of S. Typhimurium and E. coli. We report that S. Typhimurium ΔmntP ΔyiiP mutants are exquisitely sensitive to manganese and show that both YiiP and MntP contribute to manganese efflux following nitric oxide exposure. IMPORTANCE Transition metal cations are required for the function of many proteins but can mediate toxicity when present in excess. Identifying transporters that facilitate metal ion export, the conditions under which they are expressed, and the role they play in bacterial physiology is an evolving area of interest for environmental and pathogenic organisms. Determining the native targets of metal transporters has proved challenging since bioinformatic predictions, in vitro transport data, and mutant phenotypes do not always agree. This work identifies two transporters that mediate manganese efflux from the Gram-negative pathogen Salmonella enterica serovar Typhimurium in response to manganese overload and nitric oxide stress. While homologues of MntP have been characterized previously, this is the first observation of YiiP contributing to manganese export.
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22
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Charbonnier M, González-Espinoza G, Kehl-Fie TE, Lalaouna D. Battle for Metals: Regulatory RNAs at the Front Line. Front Cell Infect Microbiol 2022; 12:952948. [PMID: 35865816 PMCID: PMC9294342 DOI: 10.3389/fcimb.2022.952948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 06/09/2022] [Indexed: 11/13/2022] Open
Abstract
Metal such as iron, zinc, manganese, and nickel are essential elements for bacteria. These nutrients are required in crucial structural and catalytic roles in biological processes, including precursor biosynthesis, DNA replication, transcription, respiration, and oxidative stress responses. While essential, in excess these nutrients can also be toxic. The immune system leverages both of these facets, to limit bacterial proliferation and combat invaders. Metal binding immune proteins reduce the bioavailability of metals at the infection sites starving intruders, while immune cells intoxicate pathogens by providing metals in excess leading to enzyme mismetallation and/or reactive oxygen species generation. In this dynamic metal environment, maintaining metal homeostasis is a critical process that must be precisely coordinated. To achieve this, bacteria utilize diverse metal uptake and efflux systems controlled by metalloregulatory proteins. Recently, small regulatory RNAs (sRNAs) have been revealed to be critical post-transcriptional regulators, working in conjunction with transcription factors to promote rapid adaptation and to fine-tune bacterial adaptation to metal abundance. In this mini review, we discuss the expanding role for sRNAs in iron homeostasis, but also in orchestrating adaptation to the availability of other metals like manganese and nickel. Furthermore, we describe the sRNA-mediated interdependency between metal homeostasis and oxidative stress responses, and how regulatory networks controlled by sRNAs contribute to survival and virulence.
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Affiliation(s)
- Mathilde Charbonnier
- Université de Strasbourg, CNRS, Architecture et Réactivité de l'ARN, UPR9002, Strasbourg, France
| | | | - Thomas E Kehl-Fie
- Department of Microbiology, University of Illinois Urbana-Champaign, Urbana IL, United States.,Carl R. Woese Institute for Genomic Biology University of Illinois Urbana-Champaign, Urbana IL, United States
| | - David Lalaouna
- Université de Strasbourg, CNRS, Architecture et Réactivité de l'ARN, UPR9002, Strasbourg, France
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23
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A Unique Reverse Adaptation Mechanism Assists Bordetella pertussis in Resistance to Both Scarcity and Toxicity of Manganese. mBio 2021; 12:e0190221. [PMID: 34700381 PMCID: PMC8546581 DOI: 10.1128/mbio.01902-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The ability of bacterial pathogens to acquire essential micronutrients is critical for their survival in the host environment. Manganese plays a complex role in the virulence of a variety of pathogens due to its function as an antioxidant and enzymatic cofactor. Therefore, host cells deprive pathogens of manganese to prevent or attenuate infection. Here, we show that evolution of the human-restricted pathogen Bordetella pertussis has selected for an inhibitory duplication within a manganese exporter of the calcium:cation antiporter superfamily. Intriguingly, upon exposure to toxic levels of manganese, the nonfunctional exporter becomes operative in resister cells due to a unique reverse adaptation mechanism. However, compared with wild-type (wt) cells, the resisters carrying a functional copy of the exporter displayed strongly reduced intracellular levels of manganese and impaired growth under oxidative stress. Apparently, inactivation of the manganese exporter and the resulting accumulation of manganese in the cytosol benefited the pathogen by improving its survival under stress conditions. The inhibitory duplication within the exporter gene is highly conserved among B. pertussis strains, absent from all other Bordetella species and from a vast majority of organisms across all kingdoms of life. Therefore, we conclude that inactivation of the exporter gene represents an exceptional example of a flexible genome decay strategy employed by a human pathogen to adapt to its exclusive host.
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Nakamya MF, Ayoola MB, Shack LA, Swiatlo E, Nanduri B. The Effect of Impaired Polyamine Transport on Pneumococcal Transcriptome. Pathogens 2021; 10:pathogens10101322. [PMID: 34684271 PMCID: PMC8540371 DOI: 10.3390/pathogens10101322] [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: 09/20/2021] [Revised: 10/10/2021] [Accepted: 10/12/2021] [Indexed: 12/13/2022] Open
Abstract
Infections due to Streptococcus pneumoniae, a commensal in the nasopharynx, still claim a significant number of lives worldwide. Genome plasticity, antibiotic resistance, and limited serotype coverage of the available polysaccharide-based conjugate vaccines confounds therapeutic interventions to limit the spread of this pathogen. Pathogenic mechanisms that allow successful adaption and persistence in the host could be potential innovative therapeutic targets. Polyamines are ubiquitous polycationic molecules that regulate many cellular processes. We previously reported that deletion of polyamine transport operon potABCD, which encodes a putrescine/spermidine transporter (ΔpotABCD), resulted in an unencapsulated attenuated phenotype. Here, we characterize the transcriptome, metabolome, and stress responses of polyamine transport-deficient S. pneumoniae. Compared with the wild-type strain, the expression of genes involved in oxidative stress responses and the nucleotide sugar metabolism was reduced, while expression of genes involved in the Leloir, tagatose, and pentose phosphate pathways was higher in ΔpotABCD. A metabolic shift towards the pentose phosphate pathway will limit the synthesis of precursors of capsule polysaccharides. Metabolomics results show reduced levels of glutathione and pyruvate in the mutant. Our results also show that the potABCD operon protects pneumococci against hydrogen peroxide and nitrosative stress. Our findings demonstrate the importance of polyamine transport in pneumococcal physiology that could impact in vivo fitness. Thus, polyamine transport in pneumococci represents a novel target for therapeutic interventions.
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Affiliation(s)
- Mary F. Nakamya
- Department of Comparative Biomedical Sciences, College of Veterinary Medicine, Mississippi State University, Starkville, MS 39762, USA; (M.F.N.); (M.B.A.); (L.A.S.)
| | - Moses B. Ayoola
- Department of Comparative Biomedical Sciences, College of Veterinary Medicine, Mississippi State University, Starkville, MS 39762, USA; (M.F.N.); (M.B.A.); (L.A.S.)
| | - Leslie A. Shack
- Department of Comparative Biomedical Sciences, College of Veterinary Medicine, Mississippi State University, Starkville, MS 39762, USA; (M.F.N.); (M.B.A.); (L.A.S.)
| | - Edwin Swiatlo
- Section of Infectious Diseases, Southeast Louisiana Veterans Health Care System, New Orleans, LA 70112, USA;
| | - Bindu Nanduri
- Department of Comparative Biomedical Sciences, College of Veterinary Medicine, Mississippi State University, Starkville, MS 39762, USA; (M.F.N.); (M.B.A.); (L.A.S.)
- Correspondence: ; Tel.: +1-662-325-5859; Fax: +1-662-325-1031
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Zheng C, Wei M, Qiu J, Jia M, Zhou X, Jiao X. TroR Negatively Regulates the TroABCD System and Is Required for Resistance to Metal Toxicity and Virulence in Streptococcus suis. Appl Environ Microbiol 2021; 87:e0137521. [PMID: 34378993 PMCID: PMC8478451 DOI: 10.1128/aem.01375-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 08/05/2021] [Indexed: 11/20/2022] Open
Abstract
Streptococcus suis is an emerging zoonotic pathogen that causes severe swine and human infections. Metals are essential nutrients for life; however, excess metals are toxic to bacteria. Therefore, maintenance of intracellular metal homeostasis is important for bacterial survival. Here, we characterize a DtxR family metalloregulator, TroR, in S. suis. TroR is located upstream of the troABCD operon, whose expression was found to be significantly downregulated in response to excess manganese (Mn). Deletion of troR resulted in reduced growth when S. suis was cultured in metal-replete medium supplemented with elevated concentrations of zinc (Zn), copper (Cu), or cobalt (Co). Mn supplementation could alleviate the growth defects of the ΔtroR mutant under Zn and Co excess conditions; however, it impaired the growth of the wild-type (WT) and complemented (CΔtroR) strains under Cu excess conditions. The growth of ΔtroR was also inhibited in metal-depleted medium supplemented with elevated concentrations of Mn. Moreover, the ΔtroR mutant accumulated increased levels of intracellular Mn and Co, rather than Zn and Cu. Deletion of troR in S. suis led to significant upregulation of the troABCD operon. Furthermore, troA expression in the WT strain was induced by ferrous iron [Fe(II)] and Co and repressed by Mn and Cu; the repression of troA was mediated by TroR. Finally, TroR is required for S. suis virulence in an intranasal mouse model. Together, these data suggest that TroR is a negative regulator of the TroABCD system and contributes to resistance to metal toxicity and virulence in S. suis. IMPORTANCE Metals are essential nutrients for life; however, the accumulation of excess metals in cells can be toxic to bacteria. In the present study, we identified a metalloregulator, TroR, in Streptococcus suis, which is an emerging zoonotic pathogen. In contrast to the observations in other species that TroR homologs usually contribute to the maintenance of homeostasis of one or two metals, we demonstrated that TroR is required for resistance to the toxicity conferred by multiple metals in S. suis. We also found that deletion of troR resulted in significant upregulation of the troABCD operon, which has been demonstrated to be involved in manganese acquisition in S. suis. Moreover, we demonstrated that TroR is required for the virulence of S. suis in an intranasal mouse model. Collectively, these results suggest that TroR is a negative regulator of the TroABCD system and contributes to resistance to metal toxicity and virulence in S. suis.
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Affiliation(s)
- Chengkun Zheng
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China
| | - Man Wei
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China
| | - Jun Qiu
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China
| | - Mengdie Jia
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China
| | - Xiaohui Zhou
- Department of Pathobiology and Veterinary Science, University of Connecticut, Storrs, Connecticut, USA
| | - Xinan Jiao
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agri-food Safety and Quality, the Ministry of Agriculture of China, Yangzhou University, Yangzhou, China
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Analysis of the Manganese and MntR Regulon in Corynebacterium diphtheriae. J Bacteriol 2021; 203:e0027421. [PMID: 34370555 DOI: 10.1128/jb.00274-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Corynebacterium diphtheriae is the causative agent of a severe respiratory disease in humans. The bacterial systems required for infection are poorly understood, but the acquisition of metals such as manganese (Mn) is likely critical for host colonization. MntR is a Mn-dependent transcriptional regulator in C. diphtheriae that represses the expression of the mntABCD genes, which encode a putative ABC metal transporter. However, other targets of Mn and MntR regulation in C. diphtheriae have not been identified. In this study, we use comparisons between the gene expression profiles of wild-type C. diphtheriae strain 1737 grown without or with Mn supplementation and comparisons of gene expression between wild-type and an mntR deletion mutant to characterize the C. diphtheriae Mn and MntR regulon. MntR was observed to both repress and induce various target genes in a Mn-dependent manner. Genes induced by MntR include the Mn-superoxide dismutase, sodA, and the putative ABC transporter locus, iutABCD. DNA binding studies showed that MntR interacts with the promoter regions for several genes identified in the expression study, and a 17-bp consensus MntR DNA binding site was identified. We found that an mntR mutant displayed increased sensitivity to Mn and cadmium that could be alleviated by the additional deletion of the mntABCD transport locus, providing evidence that the MntABCD transporter functions as a Mn uptake system in C. diphtheriae. The findings in this study further our understanding of metal uptake systems and global metal regulatory networks in this important human pathogen. Importance Mechanisms for metal scavenging are critical to the survival and success of bacterial pathogens, including Corynebacterium diphtheriae. Metal import systems in pathogenic bacteria have been studied as possible vaccine components due to high conservation, critical functionality, and surface localization. In this study, we expand our understanding of the genes controlled by the global manganese regulator, MntR. We determined a role for the MntABCD transporter in manganese import using evidence from manganese and cadmium toxicity assays. Understanding the nutritional requirements of C. diphtheriae and the tools used to acquire essential metals will aid in the development of future vaccines.
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Sachla AJ, Luo Y, Helmann JD. Manganese impairs the QoxABCD terminal oxidase leading to respiration-associated toxicity. Mol Microbiol 2021; 116:729-742. [PMID: 34097790 DOI: 10.1111/mmi.14767] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 06/02/2021] [Accepted: 06/03/2021] [Indexed: 11/29/2022]
Abstract
Cell physiology relies on metalloenzymes and can be easily disrupted by imbalances in metal ion pools. Bacillus subtilis requires manganese for growth and has highly regulated mechanisms for import and efflux that help maintain homeostasis. Cells defective for manganese (Mn) efflux are highly sensitive to intoxication, but the processes impaired by Mn excess are often unknown. Here, we employed a forward genetics approach to identify pathways affected by manganese intoxication. Our results highlight a central role for the membrane-localized electron transport chain in metal intoxication during aerobic growth. In the presence of elevated manganese, there is an increased generation of reactive radical species associated with dysfunction of the major terminal oxidase, the cytochrome aa3 heme-copper menaquinol oxidase (QoxABCD). Intoxication is suppressed by diversion of menaquinol to alternative oxidases or by a mutation affecting heme A synthesis that is known to convert QoxABCD from an aa3 to a bo3 -type oxidase. Manganese sensitivity is also reduced by derepression of the MhqR regulon, which protects cells against reactive quinones. These results suggest that dysfunction of the cytochrome aa3 -type quinol oxidase contributes to metal-induced intoxication.
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Affiliation(s)
- Ankita J Sachla
- Department of Microbiology, Cornell University, Ithaca, NY, USA
| | - Yuanchan Luo
- Department of Microbiology, Cornell University, Ithaca, NY, USA.,State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - John D Helmann
- Department of Microbiology, Cornell University, Ithaca, NY, USA
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Wang Z, Shen H, He B, Teng M, Guo Q, Li X. The structural mechanism for the nucleoside tri- and diphosphate hydrolysis activity of Ntdp from Staphylococcus aureus. FEBS J 2021; 288:6019-6034. [PMID: 33955674 DOI: 10.1111/febs.15911] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 03/27/2021] [Accepted: 05/04/2021] [Indexed: 02/04/2023]
Abstract
Staphylococcus aureus is a well-known clinical pathogenic bacterium. In recent years, due to the emergence of multiple drug-resistant strains of S. aureus in clinical practice, S. aureus infections have become an increasingly severe clinical problem. Ntdp (nucleoside tri- and diphosphatase, also known as Sa1684) is a nucleotide phosphatase that has a significant effect on the proliferation of S. aureus colonies and the killing ability of the host. Here, we identified the nucleoside tri- and diphosphate hydrolysis activity of Ntdp and obtained the three-dimensional structures of apo-Ntdp and three substrate analog (ATPγ S, GDPβ S, and GTPγ S) complexes of Ntdp. Through structural analysis and biochemical verification, we illustrated the structural basis for the divalent cation selectivity, substrate recognition model, and catalytic mechanism of Ntdp. We also revealed a possible basal functional pattern of the DUF402 domain and hypothesized the potential pathways by which the protein regulates the expression of the two-component regulatory factor agr and the downstream virulence factors. Overall, the above findings provide crucial insights into our understanding of the Ntdp functional mechanism in the infection process.
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Affiliation(s)
- Zhenhua Wang
- National Synchrotron Radiation Laboratory, Hefei National Laboratory for Physical Sciences at Microscale, School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Hui Shen
- National Synchrotron Radiation Laboratory, Hefei National Laboratory for Physical Sciences at Microscale, School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Binbin He
- National Synchrotron Radiation Laboratory, Hefei National Laboratory for Physical Sciences at Microscale, School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Maikun Teng
- National Synchrotron Radiation Laboratory, Hefei National Laboratory for Physical Sciences at Microscale, School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Qiong Guo
- National Synchrotron Radiation Laboratory, Hefei National Laboratory for Physical Sciences at Microscale, School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Xu Li
- National Synchrotron Radiation Laboratory, Hefei National Laboratory for Physical Sciences at Microscale, School of Life Sciences, University of Science and Technology of China, Hefei, China
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Arginine Decarboxylase Is Essential for Pneumococcal Stress Responses. Pathogens 2021; 10:pathogens10030286. [PMID: 33801541 PMCID: PMC7998104 DOI: 10.3390/pathogens10030286] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 02/20/2021] [Accepted: 02/24/2021] [Indexed: 02/08/2023] Open
Abstract
Polyamines such as putrescine, cadaverine, and spermidine are small cationic molecules that play significant roles in cellular processes, including bacterial stress responses and host–pathogen interactions. Streptococcus pneumoniae is an opportunistic human pathogen, which causes several diseases that account for significant morbidity and mortality worldwide. As it transits through different host niches, S. pneumoniae is exposed to and must adapt to different types of stress in the host microenvironment. We earlier reported that S. pneumoniae TIGR4, which harbors an isogenic deletion of an arginine decarboxylase (ΔspeA), an enzyme that catalyzes the synthesis of agmatine in the polyamine synthesis pathway, has a reduced capsule. Here, we report the impact of arginine decarboxylase deletion on pneumococcal stress responses. Our results show that ΔspeA is more susceptible to oxidative, nitrosative, and acid stress compared to the wild-type strain. Gene expression analysis by qRT-PCR indicates that thiol peroxidase, a scavenger of reactive oxygen species and aguA from the arginine deiminase system, could be important for peroxide stress responses in a polyamine-dependent manner. Our results also show that speA is essential for endogenous hydrogen peroxide and glutathione production in S. pneumoniae. Taken together, our findings demonstrate the critical role of arginine decarboxylase in pneumococcal stress responses that could impact adaptation and survival in the host.
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Li H, Zhou X, Huang Y, Liao B, Cheng L, Ren B. Reactive Oxygen Species in Pathogen Clearance: The Killing Mechanisms, the Adaption Response, and the Side Effects. Front Microbiol 2021; 11:622534. [PMID: 33613470 PMCID: PMC7889972 DOI: 10.3389/fmicb.2020.622534] [Citation(s) in RCA: 89] [Impact Index Per Article: 29.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 12/28/2020] [Indexed: 02/05/2023] Open
Abstract
Reactive oxygen species (ROS) are attractive weapons in both antibiotic-mediated killing and host-mediated killing. However, the involvement of ROS in antibiotic-mediated killing and complexities in host environments challenge the paradigm. In the case of bacterial pathogens, the examples of some certain pathogens thriving under ROS conditions prompt us to focus on the adaption mechanism that pathogens evolve to cope with ROS. Based on these, we here summarized the mechanisms of ROS-mediated killing of either antibiotics or the host, the examples of bacterial adaption that successful pathogens evolved to defend or thrive under ROS conditions, and the potential side effects of ROS in pathogen clearance. A brief section for new antibacterial strategies centered around ROS was also addressed.
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Affiliation(s)
- Hao Li
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xuedong Zhou
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Yuyao Huang
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Binyou Liao
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Lei Cheng
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Biao Ren
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
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Pidwill GR, Gibson JF, Cole J, Renshaw SA, Foster SJ. The Role of Macrophages in Staphylococcus aureus Infection. Front Immunol 2021; 11:620339. [PMID: 33542723 PMCID: PMC7850989 DOI: 10.3389/fimmu.2020.620339] [Citation(s) in RCA: 137] [Impact Index Per Article: 45.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 12/02/2020] [Indexed: 12/23/2022] Open
Abstract
Staphylococcus aureus is a member of the human commensal microflora that exists, apparently benignly, at multiple sites on the host. However, as an opportunist pathogen it can also cause a range of serious diseases. This requires an ability to circumvent the innate immune system to establish an infection. Professional phagocytes, primarily macrophages and neutrophils, are key innate immune cells which interact with S. aureus, acting as gatekeepers to contain and resolve infection. Recent studies have highlighted the important roles of macrophages during S. aureus infections, using a wide array of killing mechanisms. In defense, S. aureus has evolved multiple strategies to survive within, manipulate and escape from macrophages, allowing them to not only subvert but also exploit this key element of our immune system. Macrophage-S. aureus interactions are multifaceted and have direct roles in infection outcome. In depth understanding of these host-pathogen interactions may be useful for future therapeutic developments. This review examines macrophage interactions with S. aureus throughout all stages of infection, with special emphasis on mechanisms that determine infection outcome.
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Affiliation(s)
- Grace R. Pidwill
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, United Kingdom
- Florey Institute, University of Sheffield, Sheffield, United Kingdom
| | - Josie F. Gibson
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, United Kingdom
- Florey Institute, University of Sheffield, Sheffield, United Kingdom
- The Bateson Centre, University of Sheffield, Sheffield, United Kingdom
| | - Joby Cole
- Florey Institute, University of Sheffield, Sheffield, United Kingdom
- Department of Infection, Immunity and Cardiovascular Disease, Medical School, University of Sheffield, Sheffield, United Kingdom
| | - Stephen A. Renshaw
- Florey Institute, University of Sheffield, Sheffield, United Kingdom
- The Bateson Centre, University of Sheffield, Sheffield, United Kingdom
- Department of Infection, Immunity and Cardiovascular Disease, Medical School, University of Sheffield, Sheffield, United Kingdom
| | - Simon J. Foster
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, United Kingdom
- Florey Institute, University of Sheffield, Sheffield, United Kingdom
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Manganese homeostasis at the host-pathogen interface and in the host immune system. Semin Cell Dev Biol 2021; 115:45-53. [PMID: 33419608 DOI: 10.1016/j.semcdb.2020.12.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 12/17/2020] [Accepted: 12/18/2020] [Indexed: 02/07/2023]
Abstract
Manganese serves as an indispensable catalytic center and the structural core of various enzymes that participate in a plethora of biological processes, including oxidative phosphorylation, glycosylation, and signal transduction. In pathogenic microorganisms, manganese is required for survival by maintaining basic biochemical activity and virulence; in contrast, the host utilizes a process known as nutritional immunity to sequester manganese from invading pathogens. Recent epidemiological and animal studies have shown that manganese increases the immune response in a wide range of vertebrates, including humans, rodents, birds, and fish. On the other hand, excess manganese can cause neurotoxicity and other detrimental effects. Here, we review recent data illustrating the essential role of manganese homeostasis at the host-pathogen interface and in the host immune system. We also discuss the accumulating body of evidence that manganese modulates various signaling pathways in immune processes. Finally, we discuss the key molecular players involved in manganese's immune regulatory function, as well as the clinical implications with respect to cancer immunotherapy.
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Li X, Chen L, Liao J, Hui J, Li W, He ZG. A novel stress-inducible CmtR-ESX3-Zn 2+ regulatory pathway essential for survival of Mycobacterium bovis under oxidative stress. J Biol Chem 2020; 295:17083-17099. [PMID: 33033071 PMCID: PMC7863910 DOI: 10.1074/jbc.ra120.013017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 09/28/2020] [Indexed: 11/06/2022] Open
Abstract
Reactive oxygen species (ROS) are an unavoidable host environmental cue for intracellular pathogens such as Mycobacterium tuberculosis and Mycobacterium bovis; however, the signaling pathway in mycobacteria for sensing and responding to environmental stress remains largely unclear. Here, we characterize a novel CmtR-Zur-ESX3-Zn2+ regulatory pathway in M. bovis that aids mycobacterial survival under oxidative stress. We demonstrate that CmtR functions as a novel redox sensor and that its expression can be significantly induced under H2O2 stress. CmtR can physically interact with the negative regulator Zur and de-represses the expression of the esx-3 operon, which leads to Zn2+ accumulation and promotion of reactive oxygen species detoxication in mycobacterial cells. Zn2+ can also act as an effector molecule of the CmtR regulator, using which the latter can de-repress its own expression for further inducing bacterial antioxidant adaptation. Consistently, CmtR can induce the expression of EsxH, a component of esx-3 operon involved in Zn2+ transportation that has been reported earlier, and inhibit phagosome maturation in macrophages. Lastly, CmtR significantly contributes to bacterial survival in macrophages and in the lungs of infected mice. Our findings reveal the existence of an antioxidant regulatory pathway in mycobacteria and provide novel information on stress-triggered gene regulation and its association with host-pathogen interaction.
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Affiliation(s)
- Xiaohui Li
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Liu Chen
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Jingjing Liao
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Jiechen Hui
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Weihui Li
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, Nanning, China
| | - Zheng-Guo He
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China; State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, Nanning, China.
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Abstract
Staphylococcus aureus is a leading agent of antibiotic-resistant bacterial infections in the world. S. aureus tightly controls metal homeostasis during infection, and disruption of metal uptake systems impairs staphylococcal virulence. We identified small molecules that interfere with metal handling in S. aureus to develop chemical probes to investigate metallobiology in this organism. Compound VU0026921 was identified as a small molecule that kills S. aureus both aerobically and anaerobically. The activity of VU0026921 is modulated by metal supplementation, is enhanced by genetic inactivation of Mn homeostasis genes, and correlates with increased cellular reactive oxygen species. Treatment with VU0026921 causes accumulation of multiple metals within S. aureus cells and concomitant upregulation of genes involved in metal detoxification. This work defines a small-molecule probe for further defining the role of metal toxicity in S. aureus and validates future antibiotic development targeting metal toxicity pathways. Metals are essential nutrients that all living organisms acquire from their environment. While metals are necessary for life, excess metal uptake can be toxic; therefore, intracellular metal levels are tightly regulated in bacterial cells. Staphylococcus aureus, a Gram-positive bacterium, relies on metal uptake and metabolism to colonize vertebrates. Thus, we hypothesized that an expanded understanding of metal homeostasis in S. aureus will lead to the discovery of pathways that can be targeted with future antimicrobials. We sought to identify small molecules that inhibit S. aureus growth in a metal-dependent manner as a strategy to uncover pathways that maintain metal homeostasis. Here, we demonstrate that VU0026921 kills S. aureus through disruption of metal homeostasis. VU0026921 activity was characterized through cell culture assays, transcriptional sequencing, compound structure-activity relationship, reactive oxygen species (ROS) generation assays, metal binding assays, and metal level analyses. VU0026921 disrupts metal homeostasis in S. aureus, increasing intracellular accumulation of metals and leading to toxicity through mismetalation of enzymes, generation of reactive oxygen species, or disruption of other cellular processes. Antioxidants partially protect S. aureus from VU0026921 killing, emphasizing the role of reactive oxygen species in the mechanism of killing, but VU0026921 also kills S. aureus anaerobically, indicating that the observed toxicity is not solely oxygen dependent. VU0026921 disrupts metal homeostasis in multiple Gram-positive bacteria, leading to increased reactive oxygen species and cell death, demonstrating the broad applicability of these findings. Further, this study validates VU0026921 as a probe to further decipher mechanisms required to maintain metal homeostasis in Gram-positive bacteria.
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Jia M, Wei M, Zhang Y, Zheng C. Transcriptomic Analysis of Streptococcus suis in Response to Ferrous Iron and Cobalt Toxicity. Genes (Basel) 2020; 11:genes11091035. [PMID: 32887434 PMCID: PMC7563783 DOI: 10.3390/genes11091035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 08/29/2020] [Accepted: 09/01/2020] [Indexed: 11/22/2022] Open
Abstract
Streptococcus suis is a zoonotic pathogen causing serious infections in swine and humans. Although metals are essential for life, excess amounts of metals are toxic to bacteria. Transcriptome-level data of the mechanisms for resistance to metal toxicity in S. suis are available for no metals other than zinc. Herein, we explored the transcriptome-level changes in S. suis in response to ferrous iron and cobalt toxicity by RNA sequencing. Many genes were differentially expressed in the presence of excess ferrous iron and cobalt. Most genes in response to cobalt toxicity showed the same expression trends as those in response to ferrous iron toxicity. qRT-PCR analysis of the selected genes confirmed the accuracy of RNA sequencing results. Bioinformatic analysis of the differentially expressed genes indicated that ferrous iron and cobalt have similar effects on the cellular processes of S. suis. Ferrous iron treatment resulted in down-regulation of several oxidative stress tolerance-related genes and up-regulation of the genes in an amino acid ABC transporter operon. Expression of several genes in the arginine deiminase system was down-regulated after ferrous iron and cobalt treatment. Collectively, our results suggested that S. suis alters the expression of multiple genes to respond to ferrous iron and cobalt toxicity.
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Affiliation(s)
- Mengdie Jia
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; (M.J.); (M.W.); (Y.Z.)
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou 225009, China
| | - Man Wei
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; (M.J.); (M.W.); (Y.Z.)
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou 225009, China
| | - Yunzeng Zhang
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; (M.J.); (M.W.); (Y.Z.)
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou 225009, China
| | - Chengkun Zheng
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; (M.J.); (M.W.); (Y.Z.)
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou 225009, China
- Correspondence: ; Tel.: +86-1520-527-9658
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Enterococcus faecalis Manganese Exporter MntE Alleviates Manganese Toxicity and Is Required for Mouse Gastrointestinal Colonization. Infect Immun 2020; 88:IAI.00058-20. [PMID: 32229614 DOI: 10.1128/iai.00058-20] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 03/21/2020] [Indexed: 01/13/2023] Open
Abstract
Bacterial pathogens encounter a variety of nutritional environments in the human host, including nutrient metal restriction and overload. Uptake of manganese (Mn) is essential for Enterococcus faecalis growth and virulence; however, it is not known how this organism prevents Mn toxicity. In this study, we examine the role of the highly conserved MntE transporter in E. faecalis Mn homeostasis and virulence. We show that inactivation of mntE results in growth restriction in the presence of excess Mn, but not other metals, demonstrating its specific role in Mn detoxification. Upon growth in the presence of excess Mn, an mntE mutant accumulates intracellular Mn, iron (Fe), and magnesium (Mg), supporting a role for MntE in Mn and Fe export and a role for Mg in offsetting Mn toxicity. Growth of the mntE mutant in excess Fe also results in increased levels of intracellular Fe, but not Mn or Mg, providing further support for MntE in Fe efflux. Inactivation of mntE in the presence of excess iron also results in the upregulation of glycerol catabolic genes and enhanced biofilm growth, and addition of glycerol is sufficient to augment biofilm growth for both the mntE mutant and its wild-type parental strain, demonstrating that glycerol availability significantly enhances biofilm formation. Finally, we show that mntE contributes to colonization of the antibiotic-treated mouse gastrointestinal (GI) tract, suggesting that E. faecalis encounters excess Mn in this niche. Collectively, these findings demonstrate that the manganese exporter MntE plays a crucial role in E. faecalis metal homeostasis and virulence.
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Genetic Regulation of Metal Ion Homeostasis in Staphylococcus aureus. Trends Microbiol 2020; 28:821-831. [PMID: 32381454 DOI: 10.1016/j.tim.2020.04.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 04/01/2020] [Accepted: 04/02/2020] [Indexed: 12/16/2022]
Abstract
The acquisition of metal ions and the proper maturation of holo-metalloproteins are essential processes for all organisms. However, metal ion homeostasis is a double-edged sword. A cytosolic accumulation of metal ions can lead to mismetallation of proteins and cell death. Therefore, maintenance of proper concentrations of intracellular metals is essential for cell fitness and pathogenesis. Staphylococcus aureus, like all bacterial pathogens, uses transcriptional metalloregulatory proteins to aid in the detection and the genetic response to changes in metal ion concentrations. Herein, we review the mechanisms by which S. aureus senses and responds to alterations in the levels of cellular zinc, iron, heme, and copper. The interplay between metal ion sensing and metal-dependent expression of virulence factors is also discussed.
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Waters LS. Bacterial manganese sensing and homeostasis. Curr Opin Chem Biol 2020; 55:96-102. [PMID: 32086169 PMCID: PMC9997548 DOI: 10.1016/j.cbpa.2020.01.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 12/11/2019] [Accepted: 01/14/2020] [Indexed: 12/17/2022]
Abstract
Manganese (Mn) plays a complex role in the survival of pathogenic and symbiotic bacteria in eukaryotic hosts and is also important for free-living bacteria to thrive in stressful environments. This review summarizes new aspects of regulatory strategies to control intracellular Mn levels and gives an overview of several newly identified families of bacterial Mn transporters. Recent illustrative examples of advances in quantification of intracellular Mn pools and characterization of the effects of Mn perturbations are highlighted. These discoveries help define mechanisms of Mn selectivity and toxicity and could enable new strategies to combat pathogenic bacteria and promote growth of desirable bacteria.
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Affiliation(s)
- Lauren S Waters
- Department of Chemistry, University of Wisconsin, Oshkosh, WI, 54901, USA.
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O'Brien J, Pastora A, Stoner A, Spatafora G. The S. mutans mntE gene encodes a manganese efflux transporter. Mol Oral Microbiol 2020; 35:129-140. [PMID: 32129937 DOI: 10.1111/omi.12286] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 02/26/2020] [Accepted: 02/28/2020] [Indexed: 11/28/2022]
Abstract
Streptococcus mutans is a colonizer of the human dentition, and under conditions of dysbiosis is the primary causative agent of dental caries. The pathogenic potential of S. mutans depends, in part, on its ability to regulate the transport of metal ions across the plasma membrane to maintain intracellular metal ion homeostasis. Research in our laboratory has focused on the Mn2+ -specific SloC lipoprotein importer and its regulator encoded by the S. mutans sloR gene. Herein, we used a bioinformatics approach to identify a gene on the S. mutans UA159 chromosome, SMU_1176, as a metal ion efflux transporter that contributes to S. mutans manganese ion homeostasis. Metal ion sensitivity assays performed with the wild-type S. mutans UA159 strain and an isogenic SMU_1176 insertion-deletion mutant, called GMS3000, revealed significantly heightened sensitivity of GMS3000 to MnSO4 challenge. 54 Mn uptake experiments support the accumulation of 54 Mn in GMS3000 cell pellets when compared to 54 Mn concentrations in UA159 or in a complemented strain of GMS3000, called GMS3001. Inductively coupled plasma mass spectrometry (ICP-MS) studies were performed in parallel to quantify intracellular manganese concentrations in these strains, the results of which corroborate the 54 Mn uptake studies, and support the SMU_1176 gene product as a Mn2+ efflux protein. Expression profiling experiments revealed de-repression of SMU_1176 gene transcription in the SloR-deficient GMS584 strain of S. mutans, especially under high manganese conditions. In conclusion, the S. mutans SMU_1176 gene, which we renamed mntE, is a manganese efflux transporter that contributes to essential metal ion homeostasis as part of the SloR regulon.
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Affiliation(s)
- Joseph O'Brien
- Program in Molecular Biology & Biochemistry, Department of Biology, Middlebury College, Middlebury, VT, USA
| | - Alexander Pastora
- Program in Molecular Biology & Biochemistry, Department of Biology, Middlebury College, Middlebury, VT, USA
| | - Andrew Stoner
- Program in Molecular Biology & Biochemistry, Department of Biology, Middlebury College, Middlebury, VT, USA
| | - Grace Spatafora
- Program in Molecular Biology & Biochemistry, Department of Biology, Middlebury College, Middlebury, VT, USA
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Hou B, Yang X, Xia H, Wu H, Ye J, Zhang H. sRNA EsrE Is Transcriptionally Regulated by the Ferric Uptake Regulator Fur in Escherichia coli. J Microbiol Biotechnol 2020; 30:127-135. [PMID: 31693839 PMCID: PMC9728176 DOI: 10.4014/jmb.1907.07026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Small RNAs (sRNAs) are widespread and play major roles in regulation circuits in bacteria. Previously, we have demonstrated that transcription of esrE is under the control of its own promoter. However, the regulatory elements involved in EsrE sRNA expression are still unknown. In this study, we found that different cis-regulatory elements exist in the promoter region of esrE. We then screened and analyzed seven potential corresponding trans-regulatory elements by using pull-down assays based on DNA affinity chromatography. Among these candidate regulators, we investigated the relationship between the ferric uptake regulator (Fur) and the EsrE sRNA. Electrophoresis mobility shift assays (EMSAs) and β-galactosidase activity assays demonstrated that Fur can bind to the promoter region of esrE, and positively regulate EsrE sRNA expression in the presence of Fe2+.
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Affiliation(s)
- Bingbing Hou
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, P.R. China,Department of Applied Biology, East China University of Science and Technology, Shanghai, P.R. China
| | - Xichen Yang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, P.R. China
| | - Hui Xia
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, P.R. China
| | - Haizhen Wu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, P.R. China,Department of Applied Biology, East China University of Science and Technology, Shanghai, P.R. China,Corresponding authors H.W. Phone: +86-021-64252507 Fax: +86-021-64252507 E-mail:
| | - Jiang Ye
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, P.R. China,Department of Applied Biology, East China University of Science and Technology, Shanghai, P.R. China
| | - Huizhan Zhang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, P.R. China,Department of Applied Biology, East China University of Science and Technology, Shanghai, P.R. China,H.Z. Phone: +86-021-64252507 Fax: +86-012-64252507 E-mail:
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Bacillus subtilis TerC Family Proteins Help Prevent Manganese Intoxication. J Bacteriol 2020; 202:JB.00624-19. [PMID: 31685536 DOI: 10.1128/jb.00624-19] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 10/29/2019] [Indexed: 12/24/2022] Open
Abstract
Manganese (Mn) is an essential element and is required for the virulence of many pathogens. In Bacillus subtilis, Mn(II) homeostasis is regulated by MntR, a Mn(II)-responsive, DNA-binding protein. MntR serves as both a repressor of Mn(II) uptake transporters and as a transcriptional activator for expression of two cation diffusion facilitator Mn(II) efflux pumps, MneP and MneS. Mutants lacking either mntR or both mneP and mneS are extremely sensitive to Mn(II) intoxication. Using transposon mutagenesis to select suppressors of Mn(II) sensitivity, we identified YceF, a TerC family membrane protein, as capable of providing Mn(II) resistance. Another TerC paralog, YkoY, is regulated by a Mn(II)-sensing riboswitch and is partially redundant in function with YceF. YkoY is regulated in parallel with an unknown function protein YybP, also controlled by a Mn(II)-sensing riboswitch. Strains lacking between one and five of these known or putative Mn(II) tolerance proteins (MneP, MneS, YceF, YkoY, and YybP) were tested for sensitivity to Mn(II) in growth assays and for accumulation of Mn(II) using inductively coupled plasma mass spectrometry. Loss of YceF and, to a lesser extent, YkoY, sensitizes cells lacking the MneP and MneS efflux transporters to Mn(II) intoxication. This sensitivity correlates with elevated intracellular Mn(II), consistent with the suggestion that TerC proteins function in Mn(II) efflux.IMPORTANCE Manganese homeostasis is primarily regulated at the level of transport. Bacillus subtilis MntR serves as a Mn(II)-activated repressor of importer genes (mntH and mntABC) and an activator of efflux genes (mneP and mneS). Elevated intracellular Mn(II) also binds to Mn-sensing riboswitches to activate transcription of yybP and ykoY, which encodes a TerC family member. Here, we demonstrate that two TerC family proteins, YceF and YkoY, help prevent Mn(II) intoxication. TerC family proteins are widespread in bacteria and may influence host-pathogen interactions, but their effects on Mn(II) homeostasis are unclear. Our results suggest that TerC proteins work by Mn(II) export under Mn(II) overload conditions to help alleviate toxicity.
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The Cation Diffusion Facilitator Family Protein EmfA Confers Resistance to Manganese Toxicity in Brucella abortus 2308 and Is an Essential Virulence Determinant in Mice. J Bacteriol 2019; 202:JB.00357-19. [PMID: 31591273 DOI: 10.1128/jb.00357-19] [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: 05/24/2019] [Accepted: 10/01/2019] [Indexed: 11/20/2022] Open
Abstract
The gene designated bab_rs23470 in the Brucella abortus 2308 genome encodes an ortholog of the cation diffusion facilitator family protein EmfA which has been linked to resistance to Mn toxicity in Rhizobium etli A B. abortus emfA null mutant derived from strain 2308 displays increased sensitivity to elevated levels of Mn in the growth medium compared to that of the parent strain but wild-type resistance to Fe, Mg, Zn, Cu, Co, and Ni. Inductively coupled plasma mass spectroscopy also indicates that the B. abortus emfA mutant retains significantly higher levels of cellular Mn after exposure to this metal than the parent strain, which is consistent with the proposed role of EmfA as a Mn exporter. Phenotypic analysis of mutants indicates that EmfA plays a much more important role in maintaining Mn homeostasis and preventing the toxicity of this metal in Brucella than does the Mn-responsive transcriptional regulator Mur. EmfA is also an essential virulence determinant for B. abortus 2308 in C57BL/6 and C57BL/6Nramp1+/+ mice, which suggests that avoiding Mn toxicity plays a critical role in Brucella pathogenesis.IMPORTANCE Mn nutrition is essential for the basic physiology and virulence of Brucella strains. The results of the study presented here demonstrate that the cation diffusion facilitator (CDF)-type metal exporter EmfA plays critical roles in maintaining Mn homeostasis and preventing Mn toxicity in Brucella and is an essential virulence determinant for these bacteria. EmfA and other cellular components involved in Mn homeostasis represent attractive targets for the development of improved vaccines and chemotherapeutic strategies for preventing and treating brucellosis in humans and animals.
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Hunsaker EW, Franz KJ. Emerging Opportunities To Manipulate Metal Trafficking for Therapeutic Benefit. Inorg Chem 2019; 58:13528-13545. [PMID: 31247859 DOI: 10.1021/acs.inorgchem.9b01029] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The indispensable requirement for metals in life processes has led to the evolution of sophisticated mechanisms that allow organisms to maintain dynamic equilibria of these ions. This dynamic control of the level, speciation, and availability of a variety of metal ions allows organisms to sustain biological processes while avoiding toxicity. When functioning properly, these mechanisms allow cells to return to their metal homeostatic set points following shifts in the metal availability or other stressors. These periods of transition, when cells are in a state of flux in which they work to regain homeostasis, present windows of opportunity to pharmacologically manipulate targets associated with metal-trafficking pathways in ways that could either facilitate a return to homeostasis and the recovery of cellular function or further push cells outside of homeostasis and into cellular distress. The purpose of this Viewpoint is to highlight emerging opportunities for chemists and chemical biologists to develop compounds to manipulate metal-trafficking processes for therapeutic benefit.
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Affiliation(s)
- Elizabeth W Hunsaker
- Department of Chemistry , Duke University , French Family Science Center, 124 Science Drive , Durham , North Carolina 27708 , United States
| | - Katherine J Franz
- Department of Chemistry , Duke University , French Family Science Center, 124 Science Drive , Durham , North Carolina 27708 , United States
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Proteomic Analysis of the Pseudomonas aeruginosa Iron Starvation Response Reveals PrrF Small Regulatory RNA-Dependent Iron Regulation of Twitching Motility, Amino Acid Metabolism, and Zinc Homeostasis Proteins. J Bacteriol 2019; 201:JB.00754-18. [PMID: 30962354 DOI: 10.1128/jb.00754-18] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 03/31/2019] [Indexed: 12/16/2022] Open
Abstract
Iron is a critical nutrient for most microbial pathogens, and the immune system exploits this requirement by sequestering iron. The opportunistic pathogen Pseudomonas aeruginosa exhibits a high requirement for iron yet an exquisite ability to overcome iron deprivation during infection. Upon iron starvation, P. aeruginosa induces the expression of several high-affinity iron acquisition systems, as well as the PrrF small regulatory RNAs (sRNAs) that mediate an iron-sparing response. Here, we used liquid chromatography-tandem mass spectrometry to conduct proteomics of the iron starvation response of P. aeruginosa Iron starvation increased levels of multiple proteins involved in amino acid catabolism, providing the capacity for iron-independent entry of carbons into the tricarboxylic acid (TCA) cycle. Proteins involved in sulfur assimilation and cysteine biosynthesis were reduced upon iron starvation, while proteins involved in iron-sulfur cluster biogenesis were increased, highlighting the central role of iron in P. aeruginosa metabolism. Iron starvation also resulted in changes in the expression of several zinc-responsive proteins and increased levels of twitching motility proteins. Subsequent analyses provided evidence for the regulation of many of these proteins via posttranscriptional regulatory events, some of which are dependent upon the PrrF sRNAs. Moreover, we showed that iron-regulated twitching motility is partially dependent upon the prrF locus, highlighting a novel link between the PrrF sRNAs and motility. These findings add to the known impacts of iron starvation in P. aeruginosa and outline potentially novel roles for the PrrF sRNAs in iron homeostasis and pathogenesis.IMPORTANCE Iron is central for growth and metabolism of almost all microbial pathogens, and as such, this element is sequestered by the host innate immune system to restrict microbial growth. Here, we used label-free proteomics to investigate the Pseudomonas aeruginosa iron starvation response, revealing a broad landscape of metabolic and metal homeostasis changes that have not previously been described. We further provide evidence that many of these processes, including twitching motility, are regulated through the iron-responsive PrrF small regulatory RNAs. As such, this study demonstrates the power of proteomics for defining stress responses of microbial pathogens.
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