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Kaushal I, Kumar B, Dogra S. Serum lipocalin-2 levels in leprosy. Indian J Dermatol Venereol Leprol 2024; 0:1-2. [PMID: 39152853 DOI: 10.25259/ijdvl_566_2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Accepted: 04/29/2024] [Indexed: 08/19/2024]
Affiliation(s)
- Ishita Kaushal
- Department of Dermatology, Venereology and Leprology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Bhushan Kumar
- Department of Dermatology, Shalby Hospital, Mohali, Punjab, India
| | - Sunil Dogra
- Department of Dermatology, Venereology and Leprology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
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2
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Shankar G, Akhter Y. Stealing survival: Iron acquisition strategies of Mycobacteriumtuberculosis. Biochimie 2024:S0300-9084(24)00142-1. [PMID: 38901792 DOI: 10.1016/j.biochi.2024.06.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2024] [Revised: 06/07/2024] [Accepted: 06/18/2024] [Indexed: 06/22/2024]
Abstract
Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), faces iron scarcity within the host due to immune defenses. This review explores the importance of iron for Mtb and its strategies to overcome iron restriction. We discuss how the host limits iron as an innate immune response and how Mtb utilizes various iron acquisition systems, particularly the siderophore-mediated pathway. The review illustrates the structure and biosynthesis of mycobactin, a key siderophore in Mtb, and the regulation of its production. We explore the potential of targeting siderophore biosynthesis and uptake as a novel therapeutic approach for TB. Finally, we summarize current knowledge on Mtb's iron acquisition and highlight promising directions for future research to exploit this pathway for developing new TB interventions.
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Affiliation(s)
- Gauri Shankar
- Department of Biotechnology, Babasaheb Bhimrao Ambedkar University, Vidya Vihar, Raebareli Road, Lucknow, Uttar Pradesh, 226 025, India
| | - Yusuf Akhter
- Department of Biotechnology, Babasaheb Bhimrao Ambedkar University, Vidya Vihar, Raebareli Road, Lucknow, Uttar Pradesh, 226 025, India.
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3
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Wang S, Fang R, Wang H, Li X, Xing J, Li Z, Song N. The role of transcriptional regulators in metal ion homeostasis of Mycobacterium tuberculosis. Front Cell Infect Microbiol 2024; 14:1360880. [PMID: 38529472 PMCID: PMC10961391 DOI: 10.3389/fcimb.2024.1360880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2023] [Accepted: 02/27/2024] [Indexed: 03/27/2024] Open
Abstract
Metal ions are essential trace elements for all living organisms and play critical catalytic, structural, and allosteric roles in many enzymes and transcription factors. Mycobacterium tuberculosis (MTB), as an intracellular pathogen, is usually found in host macrophages, where the bacterium can survive and replicate. One of the reasons why Tuberculosis (TB) is so difficult to eradicate is the continuous adaptation of its pathogen. It is capable of adapting to a wide range of harsh environmental stresses, including metal ion toxicity in the host macrophages. Altering the concentration of metal ions is the common host strategy to limit MTB replication and persistence. This review mainly focuses on transcriptional regulatory proteins in MTB that are involved in the regulation of metal ions such as iron, copper and zinc. The aim is to offer novel insights and strategies for screening targets for TB treatment, as well as for the development and design of new therapeutic interventions.
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Affiliation(s)
- Shuxian Wang
- Key Laboratory of Respiratory Tract Pathogens and Drug Therapy, School of Life Science and Technology, Shandong Second Medical University, Weifang, China
| | - Ren Fang
- Key Laboratory of Respiratory Tract Pathogens and Drug Therapy, School of Life Science and Technology, Shandong Second Medical University, Weifang, China
| | - Hui Wang
- Key Laboratory of Respiratory Tract Pathogens and Drug Therapy, School of Life Science and Technology, Shandong Second Medical University, Weifang, China
| | - Xiaotian Li
- Key Laboratory of Respiratory Tract Pathogens and Drug Therapy, School of Life Science and Technology, Shandong Second Medical University, Weifang, China
| | - Jiayin Xing
- Key Laboratory of Respiratory Tract Pathogens and Drug Therapy, School of Life Science and Technology, Shandong Second Medical University, Weifang, China
| | - Zhaoli Li
- Drug Innovation Research Center, SAFE Pharmaceutical Technology Co. Ltd., Beijing, China
| | - Ningning Song
- Key Laboratory of Respiratory Tract Pathogens and Drug Therapy, School of Life Science and Technology, Shandong Second Medical University, Weifang, China
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4
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Bazid HAS, Shoeib MA, Shoeib MM, Sharaf REA, Mosatafa MI, Abd El Gayed EM. Serum lipocalin-2 levels are decreased in patients with leprosy. Indian J Dermatol Venereol Leprol 2024; 90:59-63. [PMID: 36688893 DOI: 10.25259/ijdvl_116_2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2022] [Accepted: 05/01/2022] [Indexed: 12/13/2022]
Abstract
Background Leprosy is an infectious disease caused by Mycobacterium leprae affecting the skin, peripheral nerves and mucosae. Lipocalin-2 is a key component of the immune system's antimicrobial defence - it prevents iron uptake by binding and sequestering iron-scavenging siderophores and thus inhibits bacterial growth. Aim We evaluated serum lipocalin-2 levels in leprosy patients and its relationship to the pathogenesis and prognosis of the disease. Materials and methods In this case-control study, serum lipocalin-2 levels were measured by ELISA in 20 patients with leprosy and 20 healthy controls. Results Serum levels of lipocalin-2 were significantly reduced (P < 0.001) in leprosy patients as compared to controls. The levels were significantly higher (P < 0.014) in patients with multibacillary leprosy than in those with paucibacillary leprosy. Although the levels of lipocalin-2 were higher in patients with multiple nerve involvement as compared to those with involvement of 1 or 2 nerves, the results were not statistically significant. Limitation of the study The small sample size and the lack of different ethnic groups in the study were the major limitations of this study. Conclusion The lower lipocalin-2 concentrations in leprosy patients point to the importance of the protective functions of lipocalin-2. The elevated levels of lipocalin-2 observed in leprosy patients with neural involvement may be related to the reported neurodegenerative role of lipocalin-2.
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Affiliation(s)
- Heba A S Bazid
- Department of Dermatology, Andrology & STDs, Faculty of Medicine, Menoufia University, Menoufia, Egypt
| | - Mohamed A Shoeib
- Department of Dermatology, Andrology & STDs, Faculty of Medicine, Menoufia University, Menoufia, Egypt
| | - May M Shoeib
- Department of Dermatology, Andrology and STDs, Menoufia University, Menoufia, Egypt
| | - Raghda E A Sharaf
- Department of Dermatology, Andrology & STDs, Faculty of Medicine, Menoufia University, Menoufia, Egypt
| | - Mohammed I Mosatafa
- Department of Clinical Pathology, National Research Center Cairo, Menoufia University, Menoufia, Egypt
| | - Eman M Abd El Gayed
- Department of Medical Biochemistry, Faculty of Medicine, Menoufia University, Menoufia, Egypt
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5
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Kumar G, Adhikrao PA. Targeting Mycobacterium tuberculosis iron-scavenging tools: a recent update on siderophores inhibitors. RSC Med Chem 2023; 14:1885-1913. [PMID: 37859726 PMCID: PMC10583813 DOI: 10.1039/d3md00201b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 08/22/2023] [Indexed: 10/21/2023] Open
Abstract
Among the various bacterial infections, tuberculosis (TB) remains a life-threatening infectious disease responsible as the most significant cause of mortality and morbidity worldwide. The co-infection of human immunodeficiency virus (HIV) in association with TB burdens the healthcare system substantially. Notably, M.tb possesses defence against most antitubercular antibiotic drugs, and the efficacy of existing frontline anti-TB drugs is waning. Also, new and recurring cases of TB from resistant bacteria such as multidrug-resistant TB (MDR), extensively drug-resistant TB (XDR), and totally drug-resistant TB (TDR) strains are increasing. Hence, TB begs the scientific community to explore the new therapeutic class of compounds with their novel mechanism. M.tb requires iron from host cells to sustain, grow, and carry out several biological processes. M.tb has developed strategic methods of acquiring iron from the surrounding environment. In this communication, we discuss an overview of M.tb iron-scavenging tools. Also, we have summarized recently identified MbtA and MbtI inhibitors, which prevent M.tb from scavenging iron. These iron-scavenging tool inhibitors have the potential to be developed as anti-TB agents/drugs.
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Affiliation(s)
- Gautam Kumar
- Department of Natural Products, Chemical Sciences, National Institute of Pharmaceutical Education and Research-Hyderabad (NIPER-Hyderabad) Balanagar Hyderabad 500037 India
| | - Patil Amruta Adhikrao
- Department of Natural Products, Chemical Sciences, National Institute of Pharmaceutical Education and Research-Hyderabad (NIPER-Hyderabad) Balanagar Hyderabad 500037 India
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6
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Meikle V, Zhang L, Niederweis M. Intricate link between siderophore secretion and drug efflux in Mycobacterium tuberculosis. Antimicrob Agents Chemother 2023; 67:e0162922. [PMID: 37676015 PMCID: PMC10583673 DOI: 10.1128/aac.01629-22] [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: 12/06/2022] [Accepted: 06/30/2023] [Indexed: 09/08/2023] Open
Abstract
Drug-resistant Mycobacterium tuberculosis is a worldwide health-care problem rendering current tuberculosis (TB) drugs ineffective. Drug efflux is an important mechanism in bacterial drug resistance. The MmpL4 and MmpL5 transporters form functionally redundant complexes with their associated MmpS4 and MmpS5 proteins and constitute the inner membrane components of an essential siderophore secretion system of M. tuberculosis. Inactivating siderophore secretion is toxic for M. tuberculosis due to self-poisoning at low-iron conditions and leads to a strong virulence defect in mice. In this study, we show that M. tuberculosis mutants lacking components of the MmpS4-MmpL4 and MmpS5-MmpL5 systems are more susceptible to bedaquiline, clofazimine, and rifabutin, important drugs for treatment of drug-resistant TB. While genetic deletion experiments revealed similar functions of the MmpL4 and MmpL5 transporters in siderophore and drug secretion, complementation experiments indicated that the MmpS4-MmpL4 proteins alone are not sufficient to restore drug efflux in an M. tuberculosis mutant lacking both operons, in contrast to MmpS5-MmpL5. Importantly, an M. tuberculosis mutant lacking the recently discovered periplasmic Rv0455c protein, which is also essential for siderophore secretion, is more susceptible to the same drugs. These results reveal a promising target for the development of dual-function TB drugs, which might poison M. tuberculosis by blocking siderophore secretion and synergize with other drugs by impairing drug efflux.
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Affiliation(s)
- Virginia Meikle
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Lei Zhang
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Michael Niederweis
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
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7
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Feizi S, Awad M, Nepal R, Cooksley CM, Psaltis AJ, Wormald PJ, Vreugde S. Deferiprone-gallium-protoporphyrin (IX): A promising treatment modality against Mycobacterium abscessus. Tuberculosis (Edinb) 2023; 142:102390. [PMID: 37506532 DOI: 10.1016/j.tube.2023.102390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 07/18/2023] [Accepted: 07/24/2023] [Indexed: 07/30/2023]
Abstract
Non-Tuberculous Mycobacterial Pulmonary Disease (NTM-PD) caused by Mycobacterium abscessus is a frequent complication in patients with cystic fibrosis (CF) that worsens lung function over time. Currently, there is no cure for NTM-PD, hence new therapies are urgently required. Disrupting bacterial iron uptake pathways using gallium-protoporphyrin (IX) (GaPP), a heme analog, has been proposed as a novel antibacterial approach to tackle multi-drug resistant M. abscessus. However, the antibacterial activity of GaPP has been tested only in iron-deficient media, which cannot accurately mirror the potential activity in vivo. Herein, we investigated the potential synergistic activity between GaPP and the iron-chelating agent deferiprone (Def) in regular media against M. abscessus-infected macrophages. The safety of the treatment was assessed in vitro using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in Nuli-1 and THP-1 cell lines. Def-GaPP had synergistic activity against M. abscessus-infected macrophages where 10 mM-12.5 mg/L of Def-GaPP reduced the viability by up to 0.9 log10. Furthermore, Def-GaPP showed no cytotoxicity to Nuli-1 and THP-1 cell lines at the effective antibacterial concentrations (10 mM-12.5 mg/L) of Def- GaPP. These data encourage future investigation of Def-GaPP as a novel antimicrobial against NTM-PD.
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Affiliation(s)
- Sholeh Feizi
- Department of Surgery-Otolaryngology Head and Neck Surgery, Basil Hetzel Institute for Translational Health Research, Central Adelaide Local Health Network, Woodville South, Australia; The University of Adelaide, Adelaide, Australia
| | - Muhammed Awad
- Department of Surgery-Otolaryngology Head and Neck Surgery, Basil Hetzel Institute for Translational Health Research, Central Adelaide Local Health Network, Woodville South, Australia; The University of Adelaide, Adelaide, Australia; Faculty of Pharmacy, Department of Pharmaceutical Analytical Chemistry, Al-Azhar University, Assiut, Egypt
| | - Roshan Nepal
- Department of Surgery-Otolaryngology Head and Neck Surgery, Basil Hetzel Institute for Translational Health Research, Central Adelaide Local Health Network, Woodville South, Australia; The University of Adelaide, Adelaide, Australia
| | - Clare M Cooksley
- Department of Surgery-Otolaryngology Head and Neck Surgery, Basil Hetzel Institute for Translational Health Research, Central Adelaide Local Health Network, Woodville South, Australia; The University of Adelaide, Adelaide, Australia
| | - Alkis J Psaltis
- Department of Surgery-Otolaryngology Head and Neck Surgery, Basil Hetzel Institute for Translational Health Research, Central Adelaide Local Health Network, Woodville South, Australia; The University of Adelaide, Adelaide, Australia
| | - Peter-John Wormald
- Department of Surgery-Otolaryngology Head and Neck Surgery, Basil Hetzel Institute for Translational Health Research, Central Adelaide Local Health Network, Woodville South, Australia; The University of Adelaide, Adelaide, Australia
| | - Sarah Vreugde
- Department of Surgery-Otolaryngology Head and Neck Surgery, Basil Hetzel Institute for Translational Health Research, Central Adelaide Local Health Network, Woodville South, Australia; The University of Adelaide, Adelaide, Australia.
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Kathamuthu GR, Rajamanickam A, Sridhar R, Baskaran D, Babu S. Strongyloidiasis stercoralis coinfection is associated with altered iron status biomarkers in tuberculous lymphadenitis. Front Immunol 2022; 13:999614. [PMID: 36341407 PMCID: PMC9632344 DOI: 10.3389/fimmu.2022.999614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 10/07/2022] [Indexed: 11/26/2022] Open
Abstract
Soil-transmitted helminth [mainly Strongyloidiasis stercoralis (Ss)] and tuberculous lymphadenitis (TBL) coinfection in humans is a significant public health problem. We have previously shown that TBL+Ss+ coinfection significantly alters diverse cytokine, matrix metalloproteinase, and tissue inhibitors of metalloproteinase profiles. However, no data is available to understand the influence of Ss coinfection in TBL disease with respect to iron status biomarkers. Hence, we have studied the effect of Ss coinfection on the circulating levels of iron status (ferritin, transferrin [TF], apotransferrin [ApoT], hepcidin, hemopexin) biomarkers in TBL disease. Our results show that TBL+Ss+ and/or TBL+Ss- individuals are associated with significantly altered biochemical and hematological (red blood cell (RBC) counts, hemoglobin (Hb), hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH) were decreased, and platelets were increased) parameters compared to TBL-Ss+ individuals. Our results also show that TBL+Ss+ coinfection is associated with diminished circulating levels of ferritin, ApoT, hepcidin, and hemopexin compared to TBL+Ss- individuals. TBL+Ss+ and TBL+Ss- groups are associated with altered iron status biomarkers (decreased ferritin [TBL+Ss+ alone] and increased TF, ApoT, hepcidin and hemopexin [TBL+Ss- alone]) compared to TBL-Ss+ group. The heat map expression profile and principal component analysis (PCA) analysis of iron status biomarkers were significantly altered in TBL+Ss+ compared to TBL+Ss- and/or TBL-Ss+ individuals. A significant correlation (positive/negative) was obtained among the biochemical and hematological parameters (white blood cells (WBC)/ferritin, TF, and hepcidin, mean corpuscular hemoglobin concentration (MCHC)/ferritin and hemopexin) with iron status biomarkers. Finally, receiver operating characteristic (ROC) analysis revealed that hemopexin was significantly associated with greater specificity and sensitivity in discriminating TBL+Ss+ and TBL+Ss- coinfected individuals. Thus, our data conclude that Ss coinfection is associated with altered iron status biomarkers indicating that coinfection might alter the host-Mtb interface and could influence the disease pathogenesis.
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Affiliation(s)
- Gokul Raj Kathamuthu
- National Institutes of Health-NIRT-International Center for Excellence in Research, Chennai, India
- Indian Council of Medical Research-National Institute for Research in Tuberculosis (ICMR-NIRT), Chennai, India
- *Correspondence: Gokul Raj Kathamuthu,
| | - Anuradha Rajamanickam
- National Institutes of Health-NIRT-International Center for Excellence in Research, Chennai, India
| | | | - Dhanaraj Baskaran
- Indian Council of Medical Research-National Institute for Research in Tuberculosis (ICMR-NIRT), Chennai, India
| | - Subash Babu
- National Institutes of Health-NIRT-International Center for Excellence in Research, Chennai, India
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
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9
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Mizzi R, Plain KM, Whittington R, Timms VJ. Global Phylogeny of Mycobacterium avium and Identification of Mutation Hotspots During Niche Adaptation. Front Microbiol 2022; 13:892333. [PMID: 35602010 PMCID: PMC9121174 DOI: 10.3389/fmicb.2022.892333] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 04/06/2022] [Indexed: 12/27/2022] Open
Abstract
Mycobacterium avium is separated into four subspecies: M. avium subspecies avium (MAA), M. avium subspecies silvaticum (MAS), M. avium subspecies hominissuis (MAH), and M. avium subspecies paratuberculosis (MAP). Understanding the mechanisms of host and tissue adaptation leading to their clinical significance is vital to reduce the economic, welfare, and public health concerns associated with diseases they may cause in humans and animals. Despite substantial phenotypic diversity, the subspecies nomenclature is controversial due to high genetic similarity. Consequently, a set of 1,230 M. avium genomes was used to generate a phylogeny, investigate SNP hotspots, and identify subspecies-specific genes. Phylogeny reiterated the findings from previous work and established that Mycobacterium avium is a species made up of one highly diverse subspecies, known as MAH, and at least two clonal pathogens, named MAA and MAP. Pan-genomes identified coding sequences unique to each subspecies, and in conjunction with a mapping approach, mutation hotspot regions were revealed compared to the reference genomes for MAA, MAH, and MAP. These subspecies-specific genes may serve as valuable biomarkers, providing a deeper understanding of genetic differences between M. avium subspecies and the virulence mechanisms of mycobacteria. Furthermore, SNP analysis demonstrated common regions between subspecies that have undergone extensive mutations during niche adaptation. The findings provide insights into host and tissue specificity of this genetically conserved but phenotypically diverse species, with the potential to provide new diagnostic targets and epidemiological and therapeutic advances.
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Affiliation(s)
- Rachel Mizzi
- Farm Animal Health, School of Veterinary Science, Faculty of Science, The University of Sydney, Camden, NSW, Australia
| | - Karren M Plain
- Farm Animal Health, School of Veterinary Science, Faculty of Science, The University of Sydney, Camden, NSW, Australia.,Microbiology and Parasitology Research, Elizabeth Macarthur Agricultural Institute, Menangle, NSW, Australia
| | - Richard Whittington
- Farm Animal Health, School of Veterinary Science, Faculty of Science, The University of Sydney, Camden, NSW, Australia
| | - Verlaine J Timms
- Neilan Laboratory of Microbial and Molecular Diversity, College of Engineering, Science and Environment, The University of Newcastle, Newcastle, NSW, Australia
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10
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Choi SR, Britigan BE, Narayanasamy P. Synthesis and in vitro analysis of novel gallium tetrakis(4-methoxyphenyl)porphyrin and its long-acting nanoparticle as a potent antimycobacterial agent. Bioorg Med Chem Lett 2022; 62:128645. [PMID: 35219822 DOI: 10.1016/j.bmcl.2022.128645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 02/21/2022] [Accepted: 02/21/2022] [Indexed: 11/24/2022]
Abstract
Bacterial heme uptake pathways offer a novel target for antimicrobial drug discovery. Recently, gallium (Ga) porphyrin complexes were found to be effective against mycobacterial heme uptake pathways. The goal of the current study is to build on this foundation and develop a new Ga(III) porphyrin and its nanoparticles, formulated by a single emulsion-evaporation technique to inhibit the growth of Mycobacterium avium complex (MAC) with enhanced properties. Gallium 5,10,15,20-tetrakis(4-methoxyphenyl)porphyrin chloride (GaMeOTP) was synthesized from 5,10,15,20-tetrakis(4-methoxyphenyl)porphyrin and GaCl3. GaMeOTP showed enhanced antimicrobial activity against MAC104 and some clinical M. avium isolates. The synthesized Ga(III) porphyrin antimicrobial activity resulted in the overproduction of reactive oxygen species. Our study also demonstrated that F127 nanoparticles encapsulating GaMeOTP exhibited a smaller size than GaTP nanoparticles and a better duration of activity in MAC-infected macrophages compared to the free GaMeOTP. The nanoparticles were trafficked to endosomal compartments within MAC-infected macrophages, likely contributing to the antimicrobial activity of the drug.
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Affiliation(s)
- Seoung-Ryoung Choi
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, NE, USA
| | - Bradley E Britigan
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, NE, USA; Department of Internal Medicine, College of Medicine, University of Nebraska Medical Center, Omaha, NE, USA; Department of Internal Medicine and Research Service, Veterans Affairs Medical Center-Nebraska Western Iowa, Omaha, NE, USA
| | - Prabagaran Narayanasamy
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, NE, USA.
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11
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Prabhakar PK. Bacterial Siderophores and Their Potential Applications: A Review. Curr Mol Pharmacol 2021; 13:295-305. [PMID: 32418535 DOI: 10.2174/1874467213666200518094445] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Revised: 04/15/2020] [Accepted: 04/23/2020] [Indexed: 12/16/2022]
Abstract
The bacterial infection is one of the major health issues throughout the world. To protect humans from the infection and infectious agents, it is important to understand the mechanism of interaction of pathogens along with their susceptible hosts. This will help us to develop a novel strategy for designing effective new drugs or vaccines. As iron is an essential metal ion required for all the living systems for their growth, as well, it is needed by pathogenic bacterial cells for their growth and development inside host tissues. To get iron from the host tissues, microbes developed an iron-chelating system called siderophore and also corresponding receptors. Siderophores are low molecular weight organic complex produced by different strains of bacteria for the procurement of iron from the environment or host body under the iron deficient-conditions. Mostly in the environment at physiological pH, the iron is present in the ferric ionic form (Fe3+), which is water- insoluble and thus inaccessible for them. Such a condition promotes the generation of siderophores. These siderophores have been used in different areas such as agriculture, treatment of diseases, culture the unculturable strains of bacteria, promotion of plant growth, controlling phytopathogens, detoxification of heavy metal contamination, etc. In the medical field, siderophores can be used as "Trojan Horse Strategy", which forms a complex with antibiotics and also delivers these antibiotics to the desired locations, especially in antibiotic-resistant bacteria. The promising application of siderophore-based use of antibiotics for the management of bacterial resistance can be strategies to be used.
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Affiliation(s)
- Pranav Kumar Prabhakar
- Department of Transdisciplinary Research, Lovely Professional University, Phagwara, Punjab-144411, India
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12
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Martin DR, Sibuyi NR, Dube P, Fadaka AO, Cloete R, Onani M, Madiehe AM, Meyer M. Aptamer-Based Diagnostic Systems for the Rapid Screening of TB at the Point-of-Care. Diagnostics (Basel) 2021; 11:1352. [PMID: 34441287 PMCID: PMC8391981 DOI: 10.3390/diagnostics11081352] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 07/07/2021] [Accepted: 07/12/2021] [Indexed: 12/17/2022] Open
Abstract
The transmission of Tuberculosis (TB) is very rapid and the burden it places on health care systems is felt globally. The effective management and prevention of this disease requires that it is detected early. Current TB diagnostic approaches, such as the culture, sputum smear, skin tuberculin, and molecular tests are time-consuming, and some are unaffordable for low-income countries. Rapid tests for disease biomarker detection are mostly based on immunological assays that use antibodies which are costly to produce, have low sensitivity and stability. Aptamers can replace antibodies in these diagnostic tests for the development of new rapid tests that are more cost effective; more stable at high temperatures and therefore have a better shelf life; do not have batch-to-batch variations, and thus more consistently bind to a specific target with similar or higher specificity and selectivity and are therefore more reliable. Advancements in TB research, in particular the application of proteomics to identify TB specific biomarkers, led to the identification of a number of biomarker proteins, that can be used to develop aptamer-based diagnostic assays able to screen individuals at the point-of-care (POC) more efficiently in resource-limited settings.
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Affiliation(s)
- Darius Riziki Martin
- DSI/Mintek Nanotechnology Innovation Centre-Biolabels Node, Department of Biotechnology, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa; (D.R.M.); (N.R.S.); (P.D.); (A.O.F.); (A.M.M.)
- South African Medical Research Council Bioinformatics Unit, South African National Bioinformatics Institute, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa;
| | - Nicole Remaliah Sibuyi
- DSI/Mintek Nanotechnology Innovation Centre-Biolabels Node, Department of Biotechnology, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa; (D.R.M.); (N.R.S.); (P.D.); (A.O.F.); (A.M.M.)
| | - Phumuzile Dube
- DSI/Mintek Nanotechnology Innovation Centre-Biolabels Node, Department of Biotechnology, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa; (D.R.M.); (N.R.S.); (P.D.); (A.O.F.); (A.M.M.)
| | - Adewale Oluwaseun Fadaka
- DSI/Mintek Nanotechnology Innovation Centre-Biolabels Node, Department of Biotechnology, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa; (D.R.M.); (N.R.S.); (P.D.); (A.O.F.); (A.M.M.)
| | - Ruben Cloete
- South African Medical Research Council Bioinformatics Unit, South African National Bioinformatics Institute, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa;
| | - Martin Onani
- Department of Chemistry, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa;
| | - Abram Madimabe Madiehe
- DSI/Mintek Nanotechnology Innovation Centre-Biolabels Node, Department of Biotechnology, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa; (D.R.M.); (N.R.S.); (P.D.); (A.O.F.); (A.M.M.)
| | - Mervin Meyer
- DSI/Mintek Nanotechnology Innovation Centre-Biolabels Node, Department of Biotechnology, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa; (D.R.M.); (N.R.S.); (P.D.); (A.O.F.); (A.M.M.)
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13
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Effect of Helicobacter pylori and Helminth Coinfection on the Immune Response to Mycobacterium tuberculosis. Curr Microbiol 2021; 78:3351-3371. [PMID: 34251513 DOI: 10.1007/s00284-021-02604-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Accepted: 06/30/2021] [Indexed: 02/07/2023]
Abstract
Tuberculosis remains one of the main causes of morbidity and mortality worldwide despite decades of efforts to eradicate the disease. Although the immune response controls the infection in most infected individuals (90%), the ability of the bacterium to persist throughout the host's life leads to a risk of reactivation. Underlying conditions including human immunodeficiency virus (HIV) infection, organ transplantation, and immunosuppressive therapies are considered risk factors for progression to active disease. However, many individuals infected with Mycobacterium tuberculosis may develop clinical disease in the absence of underlying immunosuppression. It is also possible that unknown conditions may drive the progression to disease. The human microbiota can be an important modulator of the immune system; it can not only trigger inflammatory disorders, but also drive the response to other infectious diseases. In developing countries, chronic mucosal infections with Helicobacter pylori and helminths may be particularly important, as these infections frequently coexist throughout the host's life. However, little is known about the interactions of these pathogens with the immune system and their effects on M. tuberculosis clinical disease, if any. In this review, we discuss the potential effects of H. pylori and helminth co-infections on the immune response to M. tuberculosis. This may contribute to our understanding of host-pathogen interactions and in designing new strategies for the prevention and control of tuberculosis.
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14
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Holzheimer M, Buter J, Minnaard AJ. Chemical Synthesis of Cell Wall Constituents of Mycobacterium tuberculosis. Chem Rev 2021; 121:9554-9643. [PMID: 34190544 PMCID: PMC8361437 DOI: 10.1021/acs.chemrev.1c00043] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
![]()
The pathogen Mycobacterium tuberculosis (Mtb), causing
tuberculosis disease, features an extraordinary
thick cell envelope, rich in Mtb-specific lipids,
glycolipids, and glycans. These cell wall components are often directly
involved in host–pathogen interaction and recognition, intracellular
survival, and virulence. For decades, these mycobacterial natural
products have been of great interest for immunology and synthetic
chemistry alike, due to their complex molecular structure and the
biological functions arising from it. The synthesis of many of these
constituents has been achieved and aided the elucidation of their
function by utilizing the synthetic material to study Mtb immunology. This review summarizes the synthetic efforts of a quarter
century of total synthesis and highlights how the synthesis layed
the foundation for immunological studies as well as drove the field
of organic synthesis and catalysis to efficiently access these complex
natural products.
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Affiliation(s)
- Mira Holzheimer
- Stratingh Institute for Chemistry, University of Groningen, 9747 AG Groningen, The Netherlands
| | - Jeffrey Buter
- Stratingh Institute for Chemistry, University of Groningen, 9747 AG Groningen, The Netherlands
| | - Adriaan J Minnaard
- Stratingh Institute for Chemistry, University of Groningen, 9747 AG Groningen, The Netherlands
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15
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Sweet M, Villela H, Keller-Costa T, Costa R, Romano S, Bourne DG, Cárdenas A, Huggett MJ, Kerwin AH, Kuek F, Medina M, Meyer JL, Müller M, Pollock FJ, Rappé MS, Sere M, Sharp KH, Voolstra CR, Zaccardi N, Ziegler M, Peixoto R. Insights into the Cultured Bacterial Fraction of Corals. mSystems 2021; 6:e0124920. [PMID: 34156291 PMCID: PMC8269258 DOI: 10.1128/msystems.01249-20] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 05/13/2021] [Indexed: 02/06/2023] Open
Abstract
Bacteria associated with coral hosts are diverse and abundant, with recent studies suggesting involvement of these symbionts in host resilience to anthropogenic stress. Despite their putative importance, the work dedicated to culturing coral-associated bacteria has received little attention. Combining published and unpublished data, here we report a comprehensive overview of the diversity and function of culturable bacteria isolated from corals originating from tropical, temperate, and cold-water habitats. A total of 3,055 isolates from 52 studies were considered by our metasurvey. Of these, 1,045 had full-length 16S rRNA gene sequences, spanning 138 formally described and 12 putatively novel bacterial genera across the Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria phyla. We performed comparative genomic analysis using the available genomes of 74 strains and identified potential signatures of beneficial bacterium-coral symbioses among the strains. Our analysis revealed >400 biosynthetic gene clusters that underlie the biosynthesis of antioxidant, antimicrobial, cytotoxic, and other secondary metabolites. Moreover, we uncovered genomic features-not previously described for coral-bacterium symbioses-potentially involved in host colonization and host-symbiont recognition, antiviral defense mechanisms, and/or integrated metabolic interactions, which we suggest as novel targets for the screening of coral probiotics. Our results highlight the importance of bacterial cultures to elucidate coral holobiont functioning and guide the selection of probiotic candidates to promote coral resilience and improve holistic and customized reef restoration and rehabilitation efforts. IMPORTANCE Our paper is the first study to synthesize currently available but decentralized data of cultured microbes associated with corals. We were able to collate 3,055 isolates across a number of published studies and unpublished collections from various laboratories and researchers around the world. This equated to 1,045 individual isolates which had full-length 16S rRNA gene sequences, after filtering of the original 3,055. We also explored which of these had genomes available. Originally, only 36 were available, and as part of this study, we added a further 38-equating to 74 in total. From this, we investigated potential genetic signatures that may facilitate a host-associated lifestyle. Further, such a resource is an important step in the selection of probiotic candidates, which are being investigated for promoting coral resilience and potentially applied as a novel strategy in reef restoration and rehabilitation efforts. In the spirit of open access, we have ensured this collection is available to the wider research community through the web site http://isolates.reefgenomics.org/ with the hope many scientists across the globe will ask for access to these cultures for future studies.
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Affiliation(s)
- Michael Sweet
- Aquatic Research Facility, Environmental Sustainability Research Centre, University of Derby, Derby, United Kingdom
| | - Helena Villela
- Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Tina Keller-Costa
- Institute for Bioengineering and Biosciences (iBB), University of Lisbon, Lisbon, Portugal
- Instituto Superior Técnico (IST), University of Lisbon, Lisbon, Portugal
| | - Rodrigo Costa
- Institute for Bioengineering and Biosciences (iBB), University of Lisbon, Lisbon, Portugal
- Instituto Superior Técnico (IST), University of Lisbon, Lisbon, Portugal
- Department of Energy, Joint Genome Institute and Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Stefano Romano
- Gut Microbes and Health, Quadram Institute Bioscience, Norwich, United Kingdom
| | - David G. Bourne
- College of Science and Engineering, James Cook University, Townsville, Australia
- Australian Institute of Marine Science, Townsville, Australia
| | - Anny Cárdenas
- Department of Biology, University of Konstanz, Konstanz, Germany
| | - Megan J. Huggett
- School of Environmental and Life Sciences, The University of Newcastle, Ourimbah, NSW, Australia
- Centre for Marine Ecosystems Research, Edith Cowan University, Joondalup, WA, Australia
| | | | - Felicity Kuek
- Australian Institute of Marine Science, Townsville, Australia
- College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, Australia
| | - Mónica Medina
- Department of Biology, Pennsylvania State University, University Park, Pennsylvania, USA
| | - Julie L. Meyer
- Soil and Water Sciences Department, Genetics Institute, University of Florida, Gainesville, Florida, USA
| | - Moritz Müller
- Faculty of Engineering, Computing and Science, Swinburne University of Technology Sarawak Campus, Kuching, Sarawak, Malaysia
| | - F. Joseph Pollock
- Department of Biology, Pennsylvania State University, University Park, Pennsylvania, USA
- Hawaii and Palmyra Programs, The Nature Conservancy, Honolulu, Hawaii, USA
| | - Michael S. Rappé
- Hawaii Institute of Marine Biology, University of Hawaii, Kaneohe, Hawaii, USA
| | - Mathieu Sere
- Aquatic Research Facility, Environmental Sustainability Research Centre, University of Derby, Derby, United Kingdom
| | - Koty H. Sharp
- Department of Biology and Marine Biology, Roger Williams University, Bristol, Rhode Island, USA
| | | | - Nathan Zaccardi
- Department of Biology and Marine Biology, Roger Williams University, Bristol, Rhode Island, USA
| | - Maren Ziegler
- Department of Animal Ecology and Systematics, Justus Liebig University Giessen, Giessen, Germany
| | - Raquel Peixoto
- Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Red Sea Research Center (RSRC), Division of Biological and Environmental Science and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
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16
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von Rosen T, Keller LM, Weber-Ban E. Survival in Hostile Conditions: Pupylation and the Proteasome in Actinobacterial Stress Response Pathways. Front Mol Biosci 2021; 8:685757. [PMID: 34179091 PMCID: PMC8223512 DOI: 10.3389/fmolb.2021.685757] [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: 03/25/2021] [Accepted: 05/04/2021] [Indexed: 12/31/2022] Open
Abstract
Bacteria employ a multitude of strategies to cope with the challenges they face in their natural surroundings, be it as pathogens, commensals or free-living species in rapidly changing environments like soil. Mycobacteria and other Actinobacteria acquired proteasomal genes and evolved a post-translational, ubiquitin-like modification pathway called pupylation to support their survival under rapidly changing conditions and under stress. The proteasomal 20S core particle (20S CP) interacts with ring-shaped activators like the hexameric ATPase Mpa that recruits pupylated substrates. The proteasomal subunits, Mpa and pupylation enzymes are encoded in the so-called Pup-proteasome system (PPS) gene locus. Genes in this locus become vital for bacteria to survive during periods of stress. In the successful human pathogen Mycobacterium tuberculosis, the 20S CP is essential for survival in host macrophages. Other members of the PPS and proteasomal interactors are crucial for cellular homeostasis, for example during the DNA damage response, iron and copper regulation, and heat shock. The multiple pathways that the proteasome is involved in during different stress responses suggest that the PPS plays a vital role in bacterial protein quality control and adaptation to diverse challenging environments.
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Affiliation(s)
- Tatjana von Rosen
- Institute of Molecular Biology and Biophysics, ETH Zurich, Zurich, Switzerland
| | - Lena Ml Keller
- Institute of Molecular Biology and Biophysics, ETH Zurich, Zurich, Switzerland
| | - Eilika Weber-Ban
- Institute of Molecular Biology and Biophysics, ETH Zurich, Zurich, Switzerland
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17
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Klebba PE, Newton SMC, Six DA, Kumar A, Yang T, Nairn BL, Munger C, Chakravorty S. Iron Acquisition Systems of Gram-negative Bacterial Pathogens Define TonB-Dependent Pathways to Novel Antibiotics. Chem Rev 2021; 121:5193-5239. [PMID: 33724814 PMCID: PMC8687107 DOI: 10.1021/acs.chemrev.0c01005] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Iron is an indispensable metabolic cofactor in both pro- and eukaryotes, which engenders a natural competition for the metal between bacterial pathogens and their human or animal hosts. Bacteria secrete siderophores that extract Fe3+ from tissues, fluids, cells, and proteins; the ligand gated porins of the Gram-negative bacterial outer membrane actively acquire the resulting ferric siderophores, as well as other iron-containing molecules like heme. Conversely, eukaryotic hosts combat bacterial iron scavenging by sequestering Fe3+ in binding proteins and ferritin. The variety of iron uptake systems in Gram-negative bacterial pathogens illustrates a range of chemical and biochemical mechanisms that facilitate microbial pathogenesis. This document attempts to summarize and understand these processes, to guide discovery of immunological or chemical interventions that may thwart infectious disease.
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Affiliation(s)
- Phillip E Klebba
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506, United States
| | - Salete M C Newton
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506, United States
| | - David A Six
- Venatorx Pharmaceuticals, Inc., 30 Spring Mill Drive, Malvern, Pennsylvania 19355, United States
| | - Ashish Kumar
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506, United States
| | - Taihao Yang
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506, United States
| | - Brittany L Nairn
- Department of Biological Sciences, Bethel University, 3900 Bethel Drive, St. Paul, Minnesota 55112, United States
| | - Colton Munger
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506, United States
| | - Somnath Chakravorty
- Jacobs School of Medicine and Biomedical Sciences, SUNY Buffalo, Buffalo, New York 14203, United States
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18
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Fu J, Hall S, Boon EM. Recent evidence for multifactorial biofilm regulation by heme sensor proteins NosP and H-NOX. CHEM LETT 2021; 50:1095-1103. [PMID: 36051866 PMCID: PMC9432776 DOI: 10.1246/cl.200945] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/28/2023]
Abstract
Heme is involved in signal transduction by either acting as a cofactor of heme-based gas/redox sensors or binding reversely to heme-responsive proteins. Bacteria respond to low concentrations of nitric oxide (NO) to modulate group behaviors such as biofilms through the well-characterized H-NOX family and the newly discovered heme sensor protein NosP. NosP shares functional similarities with H-NOX as a heme-based NO sensor; both regulate two-component systems and/or cyclic-di-GMP metabolizing enzymes, playing roles in processes such as quorum sensing and biofilm regulation. Interestingly, aside from its role in NO signaling, recent studies suggest that NosP may also sense labile heme. In this Highlight Review, we briefly summarize H-NOX-dependent NO signaling in bacteria, then focus on recent advances in NosP-mediated NO signaling and labile heme sensing.
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Affiliation(s)
| | | | - Elizabeth M. Boon
- To whom correspondence should be addressed: Elizabeth M. Boon: Tel.: (631) 632-7945. Fax: (631) 632-7960.
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19
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Abreu R, Giri P, Quinn F. Host-Pathogen Interaction as a Novel Target for Host-Directed Therapies in Tuberculosis. Front Immunol 2020; 11:1553. [PMID: 32849525 PMCID: PMC7396704 DOI: 10.3389/fimmu.2020.01553] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 06/12/2020] [Indexed: 12/13/2022] Open
Abstract
Tuberculosis (TB) has been a transmittable human disease for many thousands of years, and M. tuberculosis is again the number one cause of death worldwide due to a single infectious agent. The intense 6- to 10-month process of multi-drug treatment, combined with the adverse side effects that can run the spectrum from gastrointestinal disturbances to liver toxicity or peripheral neuropathy are major obstacles to patient compliance and therapy completion. The consequent increase in multidrug resistant TB (MDR-TB) and extensively drug resistant TB (XDR-TB) cases requires that we increase our arsenal of effective drugs, particularly novel therapeutic approaches. Over the millennia, host and pathogen have evolved mechanisms and relationships that greatly influence the outcome of infection. Understanding these evolutionary interactions and their impact on bacterial clearance or host pathology will lead the way toward rational development of new therapeutics that favor enhancing a host protective response. These host-directed therapies have recently demonstrated promising results against M. tuberculosis, adding to the effectiveness of currently available anti-mycobacterial drugs that directly kill the organism or slow mycobacterial replication. Here we review the host-pathogen interactions during M. tuberculosis infection, describe how M. tuberculosis bacilli modulate and evade the host immune system, and discuss the currently available host-directed therapies that target these bacterial factors. Rather than provide an exhaustive description of M. tuberculosis virulence factors, which falls outside the scope of this review, we will instead focus on the host-pathogen interactions that lead to increased bacterial growth or host immune evasion, and that can be modulated by existing host-directed therapies.
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Affiliation(s)
| | | | - Fred Quinn
- Department of Infectious Diseases, University of Georgia, Athens, GA, United States
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20
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Borodulina EA, Yakovleva EV. [Iron metabolism and indicators reflecting its changes in pulmonary tuberculosis (literature review).]. Klin Lab Diagn 2020; 65:149-154. [PMID: 32163688 DOI: 10.18821/0869-2084-2020-65-3-149-154] [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: 11/28/2019] [Accepted: 12/28/2019] [Indexed: 11/17/2022]
Abstract
Iron is an essential element for human and bacteria, including mycobacterium tuberculosis. Over review includesthe literature on the problem of iron metabolism in patients with tuberculosis and with comorbid pathology HIV infection and tuberculosis. The literature was searched for when writing this review using the RSCI, CyberLeninka, Scopus, Web of Science, MedLine, PubMed databases using the following keywords: iron, ferritin, hepsidin, lactoferrin, tuberculosis, pneumonia, HIV infection. Iron compounds are involved in many redox reactions: oxygen transport, cellular respiration, the trichloroacetic acid cycle, DNA biosynthesis, and others. The ratio of intracellular and extracellular iron in the body is regulated by the low molecular weight hormone hepcidin, the mechanism of action of which is to block the function of ferroportin, an exporter of iron from cells, which leads to the accumulation of the intracellular iron pool and the prevention of the toxic effect of free iron. The role of iron in the interaction of the human body with ferro-dependent bacteria has been established. Iron is necessary for the growth and development of bacterial cells, and the methods for its production from the host are different. Information on the effect of iron metabolism on pulmonary tuberculosis is scarce and contradictory: some authors have identified a decrease in hemoglobin and transferrin in combination with elevated levels of ferritin in patients with tuberculosis; according to other sources, hyperferritinemia in tuberculosis cannot be predictive, but is a marker inflammation. At the same time, there are studies that indicate a significant increase in ferritin in patients with disseminated tuberculosis relative to other clinical forms. Currently, the incidence of tuberculosis in patients with HIV infection is increasing, while diagnostic tests are not very informative. The search for diagnostic markers in terms of iron metabolism may open up new possibilities for the diagnosis of pulmonary tuberculosis.
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Affiliation(s)
| | - E V Yakovleva
- Samara State Medical University, 443099, Samara, Russia
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21
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de Oliveira Custódio JM, Enokida IM, Gonçalves DA, Leone de Oliveira SMDV, Venturini J, Carvalho LR, Mendes RP, Paniago AMM. Dynamics of plasma micronutrient concentrations and their correlation with serum proteins and thyroid hormones in patients with paracoccidioidomycosis. PLoS One 2019; 14:e0226609. [PMID: 31877169 PMCID: PMC6932777 DOI: 10.1371/journal.pone.0226609] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Accepted: 12/01/2019] [Indexed: 01/08/2023] Open
Abstract
Minerals, such as zinc, copper, and iron are reported to play roles in chronic infectious diseases; however, their role in paracoccidioidomycosis (PCM) remains unknown. This study aimed to examine the micronutrient dynamics and their correlation with serum proteins and thyroid hormones in patients with PCM. In 14 patients with PCM and 10 healthy subjects, we evaluated the body mass index (BMI) along with serum levels of hemoglobin, iron, ferritin, zinc, copper, magnesium, albumin, globulin, thyroid stimulating hormone (TSH), thyroxine (free T4), and triiodothyronine (T3). Evaluations were conducted at the first appointment, before treatment, and at the end of the first, second, fourth, and sixth month of PCM treatment. The control group was only evaluated once. We observed that before treatment, patients with PCM, had higher levels of copper and lower level of iron than those of the control group. After one month of treatment, the iron levels increased, whereas the levels of copper after six months of treatment. Reduction in inflammatory activity, indicated by the normalization of C-reactive protein, ferritin, albumin, and globulin levels, was observed during treatment. However, no correlation was observed between the serum levels of minerals and inflammatory activity or thyroid function in this study. In conclusion, our results showed higher serum copper levels in control group compared to those in pretreatment patients; the clinical importance of this observation should be investigated in further studies. After treatment, serum copper levels showed a tendency to decrease. In addition, serum iron levels were decreased at the stage of active disease, and were increased after treatment. Thus, serum iron levels can be used as a better biomarker for treatment control.
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Affiliation(s)
| | - Iasmim Mayumi Enokida
- Scientific initiation CNPq, Faculty of Medicine - FAMED, Federal University of Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil
| | - Daniel Araujo Gonçalves
- Department of Chemistry, Minas Gerais State University - UEMG, Ituiutaba, Minas Gerais, Brazil
| | - Sandra Maria do Valle Leone de Oliveira
- Faculty of Medicine- FAMED, Center for Biological and Health Sciences- CCBS, Federal University of Mato Grosso do Sul, Mato Grosso do Sul, Campo Grande, Brazil
| | - James Venturini
- Faculty of Medicine- FAMED, Center for Biological and Health Sciences- CCBS, Federal University of Mato Grosso do Sul, Mato Grosso do Sul, Campo Grande, Brazil
| | - Lidia Raquel Carvalho
- Department of Biostatistics, Institute of Biosciences, State University Paulista "Júlio de Mesquita Filho" -UNESP, Botucatu, São Paulo Brazil
| | - Rinaldo Poncio Mendes
- Department of Tropical Diseases, Botucatu Medical School, Universidade Estadual Paulista (UNESP), Botucatu, São Paulo, Brazil
| | - Anamaria Mello Miranda Paniago
- Faculty of Medicine- FAMED, Center for Biological and Health Sciences- CCBS, Federal University of Mato Grosso do Sul, Mato Grosso do Sul, Campo Grande, Brazil
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22
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Dai Y, Shan W, Yang Q, Guo J, Zhai R, Tang X, Tang L, Tan Y, Cai Y, Chen X. Biomarkers of iron metabolism facilitate clinical diagnosis in M ycobacterium tuberculosis infection. Thorax 2019; 74:1161-1167. [PMID: 31611342 PMCID: PMC6902069 DOI: 10.1136/thoraxjnl-2018-212557] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 07/05/2019] [Accepted: 09/11/2019] [Indexed: 02/07/2023]
Abstract
BACKGROUND Perturbed iron homeostasis is a risk factor for tuberculosis (TB) progression and an indicator of TB treatment failure and mortality. Few studies have evaluated iron homeostasis as a TB diagnostic biomarker. METHODS We recruited participants with TB, latent TB infection (LTBI), cured TB (RxTB), pneumonia (PN) and healthy controls (HCs). We measured serum levels of three iron biomarkers including serum iron, ferritin and transferrin, then established and validated our prediction model. RESULTS We observed and verified that the three iron biomarker levels correlated with patient status (TB, HC, LTBI, RxTB or PN) and with the degree of lung damage and bacillary load in patients with TB. We then built a TB prediction model, neural network (NNET), incorporating the data of the three iron biomarkers. The model showed good performance for diagnosis of TB, with 83% (95% CI 77 to 87) sensitivity and 86% (95% CI 83 to 89) specificity in the training data set (n=663) and 70% (95% CI 58 to 79) sensitivity and 92% (95% CI 86 to 96) specificity in the test data set (n=220). The area under the curves (AUCs) of the NNET model to discriminate TB from HC, LTBI, RxTB and PN were all >0.83. Independent validation of the NNET model in a separate cohort (n=967) produced an AUC of 0.88 (95% CI 0.85 to 0.91) with 74% (95% CI 71 to 77) sensitivity and 92% (95% CI 87 to 96) specificity. CONCLUSIONS The established NNET TB prediction model discriminated TB from HC, LTBI, RxTB and PN in a large cohort of patients. This diagnostic assay may augment current TB diagnostics.
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Affiliation(s)
- Youchao Dai
- Guangdong Key Laboratory of Regional Immunity and Diseases, Department of Pathogen Biology, Shenzhen University School of Medicine, Shenzhen, China.,Research Institute of Infectious Diseases, Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou, China
| | - Wanshui Shan
- Shenzhen Key Laboratory of Infection & Immunity, Shenzhen Third People's Hospital, Shenzhen University School of Medicine, Shenzhen, China
| | - Qianting Yang
- Shenzhen Key Laboratory of Infection & Immunity, Shenzhen Third People's Hospital, Shenzhen University School of Medicine, Shenzhen, China
| | - Jiubiao Guo
- Guangdong Key Laboratory of Regional Immunity and Diseases, Department of Pathogen Biology, Shenzhen University School of Medicine, Shenzhen, China
| | - Rihong Zhai
- Department of Preventive Medicine, Shenzhen University Health Science Center, Shenzhen, Guangdong, China
| | - Xiaoping Tang
- Research Institute of Infectious Diseases, Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou, China
| | - Lu Tang
- Department of Biostatistics, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Yaoju Tan
- State Key Laboratory of Respiratory Disease, Department of Clinical Laboratory, Guangzhou Chest Hospital, Guangzhou, China
| | - Yi Cai
- Guangdong Key Laboratory of Regional Immunity and Diseases, Department of Pathogen Biology, Shenzhen University School of Medicine, Shenzhen, China
| | - Xinchun Chen
- Guangdong Key Laboratory of Regional Immunity and Diseases, Department of Pathogen Biology, Shenzhen University School of Medicine, Shenzhen, China
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23
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Ferguson L, Wells G, Bhakta S, Johnson J, Guzman J, Parish T, Prentice RA, Brucoli F. Integrated Target-Based and Phenotypic Screening Approaches for the Identification of Anti-Tubercular Agents That Bind to the Mycobacterial Adenylating Enzyme MbtA. ChemMedChem 2019; 14:1735-1741. [PMID: 31454170 PMCID: PMC6800809 DOI: 10.1002/cmdc.201900217] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 08/20/2019] [Indexed: 12/27/2022]
Abstract
Iron is essential for the pathogenicity and virulence of Mycobacterium tuberculosis, which synthesises salicyl-capped siderophores (mycobactins) to acquire this element from the host. MbtA is the adenylating enzyme that catalyses the initial reaction of mycobactin biosynthesis and is solely expressed by mycobacteria. A 3200-member library comprised of lead-like, structurally diverse compounds was screened against M. tuberculosis for whole-cell inhibitory activity. A set of 846 compounds that inhibited the tubercle bacilli growth were then tested for their ability to bind to MbtA using a fluorescence-based thermal shift assay and NMR-based Water-LOGSY and saturation transfer difference (STD) experiments. We identified an attractive hit molecule, 5-hydroxyindol-3-ethylamino-(2-nitro-4-trifluoromethyl)benzene (5), that bound with high affinity to MbtA and produced a MIC90 value of 13 μm. The ligand was docked into the MbtA crystal structure and displayed an excellent fit within the MbtA active pocket, adopting a binding mode different from that of the established MbtA inhibitor Sal-AMS.
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Affiliation(s)
- Lindsay Ferguson
- School of Science, University of the West of Scotland, Paisley, PA1 2BE, Scotland, UK
| | - Geoff Wells
- UCL School of Pharmacy, University College London, 29/39 Brunswick Square, London, WC1N 1AX, UK
| | - Sanjib Bhakta
- Department of Biological Sciences, Institute of Structural and Molecular Biology, Birkbeck, University of London, London, WC1E 7HX, UK
| | - James Johnson
- TB Discovery Research, Infectious Disease Research Institute, 1616 Eastlake Avenue East, Seattle, WA 98102, USA
| | - Junitta Guzman
- TB Discovery Research, Infectious Disease Research Institute, 1616 Eastlake Avenue East, Seattle, WA 98102, USA
| | - Tanya Parish
- TB Discovery Research, Infectious Disease Research Institute, 1616 Eastlake Avenue East, Seattle, WA 98102, USA
| | - Robin A. Prentice
- Seattle Structural Genomics Center for Infectious Disease, Seattle WA, USA
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, 307 Westlake Avenue North, Suite 500, Seattle, USA
| | - Federico Brucoli
- Leicester School of Pharmacy, De Montfort University, Leicester, LE1 9BH, UK
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24
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Dragset MS, Ioerger TR, Zhang YJ, Mærk M, Ginbot Z, Sacchettini JC, Flo TH, Rubin EJ, Steigedal M. Genome-wide Phenotypic Profiling Identifies and Categorizes Genes Required for Mycobacterial Low Iron Fitness. Sci Rep 2019; 9:11394. [PMID: 31388080 PMCID: PMC6684656 DOI: 10.1038/s41598-019-47905-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 07/18/2019] [Indexed: 11/26/2022] Open
Abstract
Iron is vital for nearly all living organisms, but during infection, not readily available to pathogens. Infectious bacteria therefore depend on specialized mechanisms to survive when iron is limited. These mechanisms make attractive targets for new drugs. Here, by genome-wide phenotypic profiling, we identify and categorize mycobacterial genes required for low iron fitness. Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), can scavenge host-sequestered iron by high-affinity iron chelators called siderophores. We take advantage of siderophore redundancy within the non-pathogenic mycobacterial model organism M. smegmatis (Msmeg), to identify genes required for siderophore dependent and independent fitness when iron is low. In addition to genes with a potential function in recognition, transport or utilization of mycobacterial siderophores, we identify novel putative low iron survival strategies that are separate from siderophore systems. We also identify the Msmeg in vitro essential gene set, and find that 96% of all growth-required Msmeg genes have a mutual ortholog in Mtb. Of these again, nearly 90% are defined as required for growth in Mtb as well. Finally, we show that a novel, putative ferric iron ABC transporter contributes to low iron fitness in Msmeg, in a siderophore independent manner.
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Affiliation(s)
- Marte S Dragset
- NTNU Norwegian University of Science and Technology, Centre of Molecular Inflammation Research and Department of Clinical and Molecular Medicine, Trondheim, 7491, Norway. .,Harvard T.H. Chan School of Public Health, Department of Immunology and Infectious Diseases, Boston, MA, 02115, USA. .,Germans Trias i Pujol Research Institute, Tuberculosis Research Unit, Badalona, 80916, Spain.
| | - Thomas R Ioerger
- Texas A&M University, Department of Computer Science, College Station, TX, 77843, USA
| | - Yanjia J Zhang
- Harvard T.H. Chan School of Public Health, Department of Immunology and Infectious Diseases, Boston, MA, 02115, USA
| | - Mali Mærk
- NTNU Norwegian University of Science and Technology, Centre of Molecular Inflammation Research and Department of Clinical and Molecular Medicine, Trondheim, 7491, Norway
| | - Zekarias Ginbot
- NTNU Norwegian University of Science and Technology, Centre of Molecular Inflammation Research and Department of Clinical and Molecular Medicine, Trondheim, 7491, Norway
| | - James C Sacchettini
- Texas A&M University, Department of Biochemistry and Biophysics, College Station, TX, 77843, USA
| | - Trude H Flo
- NTNU Norwegian University of Science and Technology, Centre of Molecular Inflammation Research and Department of Clinical and Molecular Medicine, Trondheim, 7491, Norway
| | - Eric J Rubin
- Harvard T.H. Chan School of Public Health, Department of Immunology and Infectious Diseases, Boston, MA, 02115, USA
| | - Magnus Steigedal
- NTNU Norwegian University of Science and Technology, Centre of Molecular Inflammation Research and Department of Clinical and Molecular Medicine, Trondheim, 7491, Norway.,Harvard T.H. Chan School of Public Health, Department of Immunology and Infectious Diseases, Boston, MA, 02115, USA.,St. Olavs University Hospital, Department of Medical Microbiology, Trondheim, 7030, Norway
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25
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Treatment of Virulent Mycobacterium tuberculosis and HIV Coinfected Macrophages with Gallium Nanoparticles Inhibits Pathogen Growth and Modulates Macrophage Cytokine Production. mSphere 2019; 4:4/4/e00443-19. [PMID: 31341073 PMCID: PMC6656872 DOI: 10.1128/msphere.00443-19] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
GaNP interrupts iron-mediated enzymatic reactions, leading to growth inhibition of virulent HIV-M. tuberculosis coinfection in macrophages, and also modulates release of cytokines that may contribute to HIV-TB pathogenesis. Macrophage-targeting GaNP are a promising therapeutic approach to provide sustained antimicrobial activity against HIV-M. tuberculosis coinfection. Tuberculosis (TB), caused by Mycobacterium tuberculosis, remains a global threat. The course of TB is negatively impacted by coexistent infection with human immunodeficiency virus type 1 (HIV). Macrophage infection with these pathogens modulates their production of pro- and anti-inflammatory cytokines, which could play a crucial role in pathogenesis. Despite the important role of macrophages in containing infection by a variety of microbes, both HIV and M. tuberculosis infect and replicate within these cells during the course of HIV-M. tuberculosis coinfection. Both M. tuberculosis and HIV require iron for growth and replication. We have previously shown that gallium encapsulated in nanoparticles, which interferes with cellular iron acquisition and utilization, inhibited the growth of HIV and an attenuated strain of M. tuberculosis within human monocyte-derived macrophages (MDMs) in vitro. Whether this was true for a fully virulent strain of M. tuberculosis and whether gallium treatment modulates cytokine production by HIV- and/or M. tuberculosis-infected macrophages have not been previously addressed. Therefore, coinfection of MDMs with HIV and a virulent M. tuberculosis strain (H37Rv) was studied in the presence of different gallium nanoparticles (GaNP). All GaNP were readily internalized by the MDMs, which provided sustained drug (gallium) release for 15 days. This led to significant growth inhibition of both HIV and M. tuberculosis within MDMs for up to 15 days after loading of the cells with all GaNP tested in our study. Cytokine analysis showed that HIV-M. tuberculosis coinfected macrophages secreted large amounts of interleukin 6 (IL-6) and IL-8 and smaller amounts of IL-1β, IL-4, and tumor necrosis factor alpha (TNF-α) cytokines. However, all GaNP were able to regulate the release of cytokines significantly. GaNP interrupts iron-mediated enzymatic reactions, leading to growth inhibition of HIV-M. tuberculosis coinfection in macrophages, and also modulates release of cytokines that may contribute to HIV-TB pathogenesis. IMPORTANCE GaNP interrupts iron-mediated enzymatic reactions, leading to growth inhibition of virulent HIV-M. tuberculosis coinfection in macrophages, and also modulates release of cytokines that may contribute to HIV-TB pathogenesis. Macrophage-targeting GaNP are a promising therapeutic approach to provide sustained antimicrobial activity against HIV-M. tuberculosis coinfection.
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26
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Fieweger RA, Wilburn KM, VanderVen BC. Comparing the Metabolic Capabilities of Bacteria in the Mycobacterium tuberculosis Complex. Microorganisms 2019; 7:E177. [PMID: 31216777 PMCID: PMC6617402 DOI: 10.3390/microorganisms7060177] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 06/10/2019] [Accepted: 06/15/2019] [Indexed: 02/06/2023] Open
Abstract
Pathogenic mycobacteria are known for their ability to maintain persistent infections in various mammals. The canonical pathogen in this genus is Mycobacterium tuberculosis and this bacterium is particularly successful at surviving and replicating within macrophages. Here, we will highlight the metabolic processes that M. tuberculosis employs during infection in macrophages and compare these findings with what is understood for other pathogens in the M. tuberculosis complex.
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Affiliation(s)
- Rachael A Fieweger
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14850, USA.
| | - Kaley M Wilburn
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14850, USA.
| | - Brian C VanderVen
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14850, USA.
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27
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Iron Supplementation Therapy, A Friend and Foe of Mycobacterial Infections? Pharmaceuticals (Basel) 2019; 12:ph12020075. [PMID: 31108902 PMCID: PMC6630247 DOI: 10.3390/ph12020075] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2019] [Revised: 05/14/2019] [Accepted: 05/15/2019] [Indexed: 12/21/2022] Open
Abstract
Iron is an essential element that is required for oxygen transfer, redox, and metabolic activities in mammals and bacteria. Mycobacteria, some of the most prevalent infectious agents in the world, require iron as growth factor. Mycobacterial-infected hosts set up a series of defense mechanisms, including systemic iron restriction and cellular iron distribution, whereas mycobacteria have developed sophisticated strategies to acquire iron from their hosts and to protect themselves from iron’s harmful effects. Therefore, it is assumed that host iron and iron-binding proteins, and natural or synthetic chelators would be keys targets to inhibit mycobacterial proliferation and may have a therapeutic potential. Beyond this hypothesis, recent evidence indicates a host protective effect of iron against mycobacterial infections likely through promoting remodeled immune response. In this review, we discuss experimental procedures and clinical observations that highlight the role of the immune response against mycobacteria under various iron availability conditions. In addition, we discuss the clinical relevance of our knowledge regarding host susceptibility to mycobacteria in the context of iron availability and suggest future directions for research on the relationship between host iron and the immune response and the use of iron as a therapeutic agent.
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28
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Ogawa N, Kato H, Kishida K, Ichihashi E, Ishige T, Yoshikawa H, Nagata Y, Ohtsubo Y, Tsuda M. Suppression of substrate inhibition in phenanthrene-degrading Mycobacterium by co-cultivation with a non-degrading Burkholderia strain. MICROBIOLOGY-SGM 2019; 165:625-637. [PMID: 30994434 DOI: 10.1099/mic.0.000801] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In natural environments contaminated by recalcitrant organic pollutants, efficient biodegradation of such pollutants has been suggested to occur through the cooperation of different bacterial species. A phenanthrene-degrading bacterial consortium, MixEPa4, from polluted soil was previously shown to include a phenanthrene-degrading strain, Mycobacterium sp. EPa45, and a non-polycyclic aromatic hydrocarbon (PAH)-degrading strain, Burkholderia sp. Bcrs1W. In this study, we show that addition of phenanthrene to rich liquid medium resulted in the transient growth arrest of EPa45 during its degradation of phenanthrene. RNA-sequencing analysis of the growth-arrested cells showed the phenanthrene-dependent induction of genes that were predicted to be involved in the catabolism of this compound, and many other cell systems, such as a ferric iron-uptake, were up-regulated, implying iron deficiency of the cells. This negative effect of phenanthrene became much more apparent when using phenanthrene-containing minimal agar medium; colony formation of EPa45 on such agar was significantly inhibited in the presence of phenanthrene and its intermediate degradation products. However, growth inhibition was suppressed by the co-residence of viable Bcrs1W cells. Various Gram-negative bacterial strains, including the three other strains from MixEPa4, also exhibited varying degrees of suppression of the growth inhibition effect on EPa45, strongly suggesting that this effect is not strain-specific. Growth inhibition of EPa45 was also observed by other PAHs, biphenyl and naphthalene, and these two compounds and phenanthrene also inhibited the growth of another mycobacterial strain, M. vanbaalenii PYR-1, that can use them as carbon sources. These phenomena of growth inhibition were also suppressed by Bcrs1W. Our findings suggest that, in natural environments, various non-PAH-degrading bacterial strains play potentially important roles in the facilitation of PAH degradation by the co-residing mycobacteria.
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Affiliation(s)
- Natsumi Ogawa
- 1 Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Sendai 980-8577, Japan
| | - Hiromi Kato
- 1 Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Sendai 980-8577, Japan
| | - Kouhei Kishida
- 1 Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Sendai 980-8577, Japan
| | - Eikichi Ichihashi
- 1 Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Sendai 980-8577, Japan
| | - Taichiro Ishige
- 2 Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Tokyo 156-8502, Japan
| | - Hirofumi Yoshikawa
- 2 Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Tokyo 156-8502, Japan
| | - Yuji Nagata
- 1 Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Sendai 980-8577, Japan
| | - Yoshiyuki Ohtsubo
- 1 Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Sendai 980-8577, Japan
| | - Masataka Tsuda
- 1 Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Sendai 980-8577, Japan
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29
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Dahl SL, Woodworth JS, Lerche CJ, Cramer EP, Nielsen PR, Moser C, Thomsen AR, Borregaard N, Cowland JB. Lipocalin-2 Functions as Inhibitor of Innate Resistance to Mycobacterium tuberculosis. Front Immunol 2018; 9:2717. [PMID: 30534124 PMCID: PMC6275245 DOI: 10.3389/fimmu.2018.02717] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 11/05/2018] [Indexed: 01/14/2023] Open
Abstract
Lipocalin-2 is a constituent of the neutrophil secondary granules and is expressed de novo by macrophages and epithelium in response to inflammation. Lipocalin-2 acts in a bacteriostatic fashion by binding iron-loaded siderophores required for bacterial growth. Mycobacterium tuberculosis (M.tb) produces siderophores that can be bound by lipocalin-2. The impact of lipocalin-2 in the innate immune response toward extracellular bacteria has been established whereas the effect on intracellular bacteria, such as M.tb, is less well-described. Here we show that lipocalin-2 surprisingly confers a growth advantage on M.tb in the early stages of infection (3 weeks post-challenge). Using mixed bone marrow chimeras, we demonstrate that lipocalin-2 derived from granulocytes, but not from epithelia and macrophages, leads to increased susceptibility to M.tb infection. In contrast, lipocalin-2 is not observed to promote mycobacterial growth at later stages of M.tb infection. We demonstrate co-localization of granulocytes and mycobacteria within the nascent granulomas at week 3 post-challenge, but not in the consolidated granulomas at week 5. We hypothesize that neutrophil-derived lipocalin-2 acts to supply a source of iron to M.tb in infected macrophages within the immature granuloma, thereby facilitating mycobacterial growth.
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Affiliation(s)
- Sara Louise Dahl
- Granulocyte Research Laboratory, Rigshospitalet, Copenhagen, Denmark
| | - Joshua S Woodworth
- Department of Infectious Disease Immunology, Statens Serum Institute, Copenhagen, Denmark
| | | | | | - Pia Rude Nielsen
- Department of Pathology, Zealand University Hospital, Roskilde, Denmark
| | - Claus Moser
- Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark
| | - Allan Randrup Thomsen
- Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
| | - Niels Borregaard
- Granulocyte Research Laboratory, Rigshospitalet, Copenhagen, Denmark
| | - Jack Bernard Cowland
- Granulocyte Research Laboratory, Rigshospitalet, Copenhagen, Denmark.,Department of Clinical Genetics, Rigshospitalet, Copenhagen, Denmark
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30
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Chao A, Sieminski PJ, Owens CP, Goulding CW. Iron Acquisition in Mycobacterium tuberculosis. Chem Rev 2018; 119:1193-1220. [PMID: 30474981 DOI: 10.1021/acs.chemrev.8b00285] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The highly contagious disease tuberculosis (TB) is caused by the bacterium Mycobacterium tuberculosis (Mtb), which has been evolving drug resistance at an alarming rate. Like all human pathogens, Mtb requires iron for growth and virulence. Consequently, Mtb iron transport is an emerging drug target. However, the development of anti-TB drugs aimed at these metabolic pathways has been restricted by the dearth of information on Mtb iron acquisition. In this Review, we describe the multiple strategies utilized by Mtb to acquire ferric iron and heme iron. Mtb iron uptake is a complex process, requiring biosynthesis and subsequent export of Mtb siderophores, followed by ferric iron scavenging and ferric-siderophore import into Mtb. Additionally, Mtb possesses two possible heme uptake pathways and an Mtb-specific mechanism of heme degradation that yields iron and novel heme-degradation products. We conclude with perspectives for potential therapeutics that could directly target Mtb heme and iron uptake machineries. We also highlight how hijacking Mtb heme and iron acquisition pathways for drug import may facilitate drug transport through the notoriously impregnable Mtb cell wall.
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Affiliation(s)
| | | | - Cedric P Owens
- Schmid College of Science and Technology , Chapman University , Orange , California 92866 , United States
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31
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A reevaluation of iron binding by Mycobactin J. J Biol Inorg Chem 2018; 23:995-1007. [DOI: 10.1007/s00775-018-1592-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 07/03/2018] [Indexed: 12/21/2022]
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32
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Perumal R, Naidoo K, Padayatchi N. TB epidemiology: where are the young women? Know your tuberculosis epidemic, know your response. BMC Public Health 2018; 18:417. [PMID: 29587706 PMCID: PMC5872528 DOI: 10.1186/s12889-018-5362-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2017] [Accepted: 03/22/2018] [Indexed: 11/10/2022] Open
Abstract
Background The global predominance of tuberculosis in men has received significant attention. However, epidemiological studies now demonstrate that there is an increased representation of young women with tuberculosis, especially in high HIV burden settings where young women bear a disproportionate burden of HIV. The role of the HIV epidemic, as well as changes in behavioural, biological, and structural risk factors are explored as potential explanations for the increasing burden of tuberculosis in young women. Discussion As young women are particularly vulnerable to HIV infection in sub-Saharan Africa, it is unsurprising that the TB epidemic in this setting has become increasingly feminised. This age-sex trend of TB in South Africa is similar to WHO estimates for other countries with a high HIV prevalence where there are more female than male cases notified up to the age of 25 years. The high prevalence of anaemia of chronic disease in young women with HIV is an additional potential reason for their increased TB risk. The widespread use of injectable medroxyprogesterone acetate contraception, which has been shown to possess selective glucocorticoid effect and oestrogen suppression, in young women may be an important emerging biological risk factor for tuberculosis in young women. Behavioural factors such as alcohol use and tobacco smoking patterns are further factors which may be responsible for the narrowing of the sex gap in TB epidemiology. In comparison to the significantly higher alcohol consumption rates in men globally, there is a narrowing gap in alcohol consumption between the sexes in South Africa with alarming rates of alcohol abuse in young women. There is a similar narrowing of the tobacco smoking gap between the sexes in South Africa, with increasing smoking prevalence in young women. Conclusion With nearly 70% of all TB patients being co-infected with HIV in our setting, it is not surprising that the age and sex distribution of TB is increasingly resembling the distribution of HIV in this region of dual hyperendemicity. New TB service design must begin to reflect the presence of young women as a significant group burdened by the disease.
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Affiliation(s)
- Rubeshan Perumal
- Centre for the AIDS Programme of Research in South Africa, Nelson R Mandela School of Medicine, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa. .,Division of Pulmonology and Critical Care, Department of Internal Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa. .,Centre for the AIDS Programme of Research in South Africa, Doris Duke Medical Research Institute (2nd floor), 719 Umbilo Road, Private Bag X7, Congella, Durban, 4013, South Africa.
| | - Kogieleum Naidoo
- Centre for the AIDS Programme of Research in South Africa, Nelson R Mandela School of Medicine, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa.,Medical Research Council-CAPRISA HIV-TB Pathogenesis and Treatment Research Unit, Doris Duke Medical Research Institute, University of KwaZulu-Natal, Durban, South Africa
| | - Nesri Padayatchi
- Centre for the AIDS Programme of Research in South Africa, Nelson R Mandela School of Medicine, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa.,Medical Research Council-CAPRISA HIV-TB Pathogenesis and Treatment Research Unit, Doris Duke Medical Research Institute, University of KwaZulu-Natal, Durban, South Africa
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33
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Choi SR, Britigan BE, Switzer B, Hoke T, Moran D, Narayanasamy P. In Vitro Efficacy of Free and Nanoparticle Formulations of Gallium(III) meso-Tetraphenylporphyrine against Mycobacterium avium and Mycobacterium abscessus and Gallium Biodistribution in Mice. Mol Pharm 2018; 15:1215-1225. [DOI: 10.1021/acs.molpharmaceut.7b01036] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Seoung-ryoung Choi
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, Nebraska 68198, United States
| | - Bradley E. Britigan
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, Nebraska 68198, United States
- Department of Internal Medicine, College of Medicine, University of Nebraska Medical Center, Omaha, Nebraska 68198, United States
- Research Service, Veterans Affairs Medical Center-Nebraska Western Iowa, Omaha, Nebraska 68105, United States
| | - Barbara Switzer
- Department of Internal Medicine, College of Medicine, University of Nebraska Medical Center, Omaha, Nebraska 68198, United States
- Research Service, Veterans Affairs Medical Center-Nebraska Western Iowa, Omaha, Nebraska 68105, United States
| | - Traci Hoke
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, Nebraska 68198, United States
- Department of Internal Medicine, College of Medicine, University of Nebraska Medical Center, Omaha, Nebraska 68198, United States
- Research Service, Veterans Affairs Medical Center-Nebraska Western Iowa, Omaha, Nebraska 68105, United States
| | - David Moran
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, Nebraska 68198, United States
| | - Prabagaran Narayanasamy
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, Nebraska 68198, United States
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34
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Harrington-Kandt R, Stylianou E, Eddowes LA, Lim PJ, Stockdale L, Pinpathomrat N, Bull N, Pasricha J, Ulaszewska M, Beglov Y, Vaulont S, Drakesmith H, McShane H. Hepcidin deficiency and iron deficiency do not alter tuberculosis susceptibility in a murine M.tb infection model. PLoS One 2018; 13:e0191038. [PMID: 29324800 PMCID: PMC5764373 DOI: 10.1371/journal.pone.0191038] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 12/27/2017] [Indexed: 12/20/2022] Open
Abstract
Tuberculosis (TB), caused by the macrophage-tropic pathogen Mycobacterium tuberculosis (M.tb) is a highly prevalent infectious disease. Since an immune correlate of protection or effective vaccine have yet to be found, continued research into host-pathogen interactions is important. Previous literature reports links between host iron status and disease outcome for many infections, including TB. For some extracellular bacteria, the iron regulatory hormone hepcidin is essential for protection against infection. Here, we investigated hepcidin (encoded by Hamp1) in the context of murine M.tb infection. Female C57BL/6 mice were infected with M.tb Erdman via aerosol. Hepatic expression of iron-responsive genes was measured by qRT-PCR and bacterial burden determined in organ homogenates. We found that hepatic Hamp1 mRNA levels decreased post-infection, and correlated with a marker of BMP/SMAD signalling pathways. Next, we tested the effect of Hamp1 deletion, and low iron diets, on M.tb infection. Hamp1 knockout mice did not have a significantly altered M.tb mycobacterial load in either the lungs or spleen. Up to 10 weeks of dietary iron restriction did not robustly affect disease outcome despite causing iron deficiency anaemia. Taken together, our data indicate that unlike with many other infections, hepcidin is decreased following M.tb infection, and show that hepcidin ablation does not influence M.tb growth in vivo. Furthermore, because even severe iron deficiency did not affect M.tb mycobacterial load, we suggest that the mechanisms M.tb uses to scavenge iron from the host must be extremely efficient, and may therefore represent potential targets for drugs and vaccines.
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Affiliation(s)
| | - Elena Stylianou
- Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Lucy A. Eddowes
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Pei Jin Lim
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Lisa Stockdale
- Department of Immunology and Infection, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | | | - Naomi Bull
- Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Janet Pasricha
- Jenner Institute, University of Oxford, Oxford, United Kingdom
| | | | - Yulia Beglov
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Sophie Vaulont
- Institut Cochin, INSERM 567, CNRS 8104, Université Paris 5, Paris, France
| | - Hal Drakesmith
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
- * E-mail: (HD); (HMcS)
| | - Helen McShane
- Jenner Institute, University of Oxford, Oxford, United Kingdom
- * E-mail: (HD); (HMcS)
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35
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Briffotaux J, Huang W, Wang X, Gicquel B. MmpS5/MmpL5 as an efflux pump in Mycobacterium species. Tuberculosis (Edinb) 2017; 107:13-19. [DOI: 10.1016/j.tube.2017.08.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 07/31/2017] [Accepted: 08/03/2017] [Indexed: 10/19/2022]
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36
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Elemental Ingredients in the Macrophage Cocktail: Role of ZIP8 in Host Response to Mycobacterium tuberculosis. Int J Mol Sci 2017; 18:ijms18112375. [PMID: 29120360 PMCID: PMC5713344 DOI: 10.3390/ijms18112375] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Revised: 11/01/2017] [Accepted: 11/06/2017] [Indexed: 12/16/2022] Open
Abstract
Tuberculosis (TB) is a global epidemic caused by the infection of human macrophages with the world’s most deadly single bacterial pathogen, Mycobacterium tuberculosis (M.tb). M.tb resides in a phagosomal niche within macrophages, where trace element concentrations impact the immune response, bacterial metal metabolism, and bacterial survival. The manipulation of micronutrients is a critical mechanism of host defense against infection. In particular, the human zinc transporter Zrt-/Irt-like protein 8 (ZIP8), one of 14 ZIP family members, is important in the flux of divalent cations, including zinc, into the cytoplasm of macrophages. It also has been observed to exist on the membrane of cellular organelles, where it can serve as an efflux pump that transports zinc into the cytosol. ZIP8 is highly inducible in response to M.tb infection of macrophages, and we have observed its localization to the M.tb phagosome. The expression, localization, and function of ZIP8 and other divalent cation transporters within macrophages have important implications for TB prevention and dissemination and warrant further study. In particular, given the importance of zinc as an essential nutrient required for humans and M.tb, it is not yet clear whether ZIP-guided zinc transport serves as a host protective factor or, rather, is targeted by M.tb to enable its phagosomal survival.
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37
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Villellas C, Coeck N, Meehan CJ, Lounis N, de Jong B, Rigouts L, Andries K. Unexpected high prevalence of resistance-associated Rv0678 variants in MDR-TB patients without documented prior use of clofazimine or bedaquiline. J Antimicrob Chemother 2017; 72:684-690. [PMID: 28031270 PMCID: PMC5400087 DOI: 10.1093/jac/dkw502] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Accepted: 10/25/2016] [Indexed: 11/13/2022] Open
Abstract
Objectives Resistance-associated variants (RAVs) in Rv0678 , a regulator of the MmpS5-MmpL5 efflux pump, have been shown to lead to increased MICs of bedaquiline (2- to 8- fold) and clofazimine (2- to 4-fold). The prevalence of these Rv0678 RAVs in clinical isolates and their impact on treatment outcomes are important factors to take into account in bedaquiline treatment guidelines. Methods Baseline isolates from two bedaquiline MDR-TB clinical trials were sequenced for Rv0678 RAVs and corresponding bedaquiline MICs were determined on 7H11 agar. Rv0678 RAVs were also investigated in non-MDR-TB sequences of a population-based cohort. Results Rv0678 RAVs were identified in 23/347 (6.3%) of MDR-TB baseline isolates. Surprisingly, bedaquiline MICs for these isolates were high (> 0.24 mg/L, n = 8), normal (0.03-0.24 mg/L, n = 11) or low (< 0.03 mg/L, n = 4). A variant at position -11 in the intergenic region mmpS5 - Rv0678 was identified in 39 isolates (11.3%) and appeared to increase the susceptibility to bedaquiline. In non-MDR-TB isolates, the frequency of Rv0678 RAVs was lower (6/852 or 0.7%). Competition experiments suggested that rifampicin was not the drug selecting for Rv0678 RAVs. Conclusions RAVs in Rv0678 occur more frequently in MDR-TB patients than previously anticipated, are not associated with prior use of bedaquiline or clofazimine, and in the majority of cases do not lead to bedaquiline MICs above the provisional breakpoint (0.24 mg/L). Their origin remains unknown. Given the variety of RAVs in Rv0678 and their variable effects on the MIC, only phenotypic drug-susceptibility methods can currently be used to assess bedaquiline susceptibility.
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Affiliation(s)
| | - Nele Coeck
- Institute of Tropical Medicine, Antwerp, Belgium
| | | | - Nacer Lounis
- Janssen Research and Development, Beerse, Belgium
| | | | - Leen Rigouts
- Institute of Tropical Medicine, Antwerp, Belgium
| | - Koen Andries
- Janssen Research and Development, Beerse, Belgium
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Moniz T, Leite A, Silva T, Gameiro P, Gomes M, de Castro B, Rangel M. The influence of functional groups on the permeation and distribution of antimycobacterial rhodamine chelators. J Inorg Biochem 2017; 175:138-147. [DOI: 10.1016/j.jinorgbio.2017.07.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 07/10/2017] [Accepted: 07/16/2017] [Indexed: 10/19/2022]
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Application of Distributive Conjugal DNA Transfer in Mycobacterium smegmatis To Establish a Genome-Wide Synthetic Genetic Array. J Bacteriol 2017; 199:JB.00410-17. [PMID: 28784812 DOI: 10.1128/jb.00410-17] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 07/27/2017] [Indexed: 11/20/2022] Open
Abstract
Genetic redundancy can obscure phenotypic effects of single-gene mutations. Two individual mutations may be viable separately but are lethal when combined, thus synthetically linking the two gene products in an essential process. Synthetic genetic arrays (SGAs), in which defined mutations are combined, provide a powerful approach to identify novel genetic interactions and redundant pathways. A genome-scale SGA can offer an initial assignment of function to hypothetical genes by uncovering interactions with known genes or pathways. Here, we take advantage of the chromosomal conjugation system of Mycobacterium smegmatis to combine individual donor and recipient mutations on a genome-wide scale. We demonstrated the feasibility of a high-throughput mycobacterial SGA (mSGA) screen by using mutants of esx3, fxbA, and recA as query genes, which were combined with an arrayed library of transposon mutants by conjugation. The mSGA identified interacting genes that we had predicted and, most importantly, identified novel interacting genes-encoding both proteins and a noncoding RNA (ncRNA). In combination with other molecular genetic approaches, the mSGA has great potential to both reduce the high number of conserved hypothetical protein annotations in mycobacterial genomes and further define mycobacterial pathways and gene interactions.IMPORTANCE Mycobacterium smegmatis is the model organism of choice for the study of mycobacterial pathogens, because it is a fast-growing nonpathogenic species harboring many genes that are conserved throughout mycobacteria. In this work, we describe a synthetic genetic array (mSGA) approach for M. smegmatis, which combines mutations on a genome-wide scale with high efficiency. Analysis of the double mutant strains enables the identification of interacting genes and pathways that are normally hidden by redundant biological pathways. The mSGA is a powerful genetic tool that enables functions to be assigned to the many conserved hypothetical genes found in all mycobacterial species.
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Yang X, Wu JB, Liu Y, Xiong Y, Ji P, Wang SJ, Chen Y, Zhao GP, Lu SH, Wang Y. Identification of mycobacterial bacterioferritin B for immune screening of tuberculosis and latent tuberculosis infection. Tuberculosis (Edinb) 2017; 107:119-125. [PMID: 29050758 DOI: 10.1016/j.tube.2017.08.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 08/14/2017] [Accepted: 08/20/2017] [Indexed: 10/19/2022]
Abstract
OBJECTIVES It remains necessary and urgent to search for novel mycobacterial antigens to increase the sensitivity and specificity for tuberculosis (TB) diagnosis and latent TB infection (LTBI) screening. Antigens capable of inducing strong immune responses during Mycobacterium tuberculosis (M.tb) infection would be good candidates. METHODS Cellular responses specific to M.tb derived bacterioferritin B (BfrB) were assessed by IFN-γ ELISPOT in three human cohorts, including healthy controls (HCs), LTBI population and pulmonary TB (PTB) patients. Its significance in TB diagnosis and LTBI identification was further analyzed. RESULTS BfrB-specific IFN-γ responses in PTB and LTBI groups were significantly higher than that in HCs. However, BfrB-specific IFN-γ release was not as strong as that to ESAT-6 or CFP-10 in PTB patients whereas comparable in LTBI cohort with possible complementary properties to ESAT-6 or CFP-10. More interestingly, there were a considerable number of HCs with high BfrB-specific cellular responses. When HCs with high BfrB-specific cellular responses were subgrouped into ESAT-6/CFP-10hi (SFUs = 3, 4, 5) and ESAT-6/CFP-10lo (SFUs < 3) groups, those who belonged to ESAT-6/CFP-10hi group exhibited higher PPD responsiveness than ESAT-6/CFP-10lo group. CONCLUSIONS PTB and LTBI groups exhibit higher BfrB-specific IFN-γ responses than HCs. Although BfrB is not as immunodominant as ESAT-6/CFP-10 during acute M.tb infection, comparable BfrB-specific cellular immune responses are observed in LTBI population with the potential to increase the sensitivity for LTBI screening. Moreover, strong BfrB-specific IFN-γ release in the healthy cohort is probably cautionary in identifying leaky LTBI from HCs. BfrB might thus be considered as an additional biomarker antigen for LTBI identification.
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Affiliation(s)
- Xinyu Yang
- Shanghai Jiao Tong University School of Medicine, Shanghai Institute of Immunology, Shanghai, 200025, China
| | - Jia-Bao Wu
- Shanghai Jiao Tong University School of Medicine, Shanghai Institute of Immunology, Shanghai, 200025, China; Department of Microbiology, School of Life Sciences, Fudan University, Shanghai, 200438, China
| | - Ying Liu
- Shanghai Jiao Tong University School of Medicine, Shanghai Institute of Immunology, Shanghai, 200025, China
| | - Yanqing Xiong
- Shanghai Public Health Clinical Center, Key Laboratory of Medical Molecular Virology of MOE/MOH, Fudan University, 2901 Caolang Rd., Shanghai, 201508, China
| | - Ping Ji
- Shanghai Jiao Tong University School of Medicine, Shanghai Institute of Immunology, Shanghai, 200025, China
| | - Shu-Jun Wang
- Shanghai Jiao Tong University School of Medicine, Shanghai Institute of Immunology, Shanghai, 200025, China
| | - Yingying Chen
- Shanghai Jiao Tong University School of Medicine, Shanghai Institute of Immunology, Shanghai, 200025, China
| | - Guo-Ping Zhao
- Department of Microbiology, School of Life Sciences, Fudan University, Shanghai, 200438, China; Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai, Shanghai, 201200, China
| | - Shui-Hua Lu
- Shanghai Public Health Clinical Center, Key Laboratory of Medical Molecular Virology of MOE/MOH, Fudan University, 2901 Caolang Rd., Shanghai, 201508, China.
| | - Ying Wang
- Shanghai Jiao Tong University School of Medicine, Shanghai Institute of Immunology, Shanghai, 200025, China; Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai, Shanghai, 201200, China.
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Fang Z, Newton-Foot M, Sampson SL, Gey van Pittius NC. Two promoters in the esx-3 gene cluster of Mycobacterium smegmatis respond inversely to different iron concentrations in vitro. BMC Res Notes 2017; 10:426. [PMID: 28841831 PMCID: PMC6389172 DOI: 10.1186/s13104-017-2752-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 08/23/2017] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND The ESX secretion system, also known as the Type VII secretion system, is mostly found in mycobacteria and plays important roles in nutrient acquisition and host pathogenicity. One of the five ESXs, ESX-3, is associated with mycobactin-mediated iron acquisition. Although the functions of some of the membrane-associated components of the ESX systems have been described, the role of by mycosin-3 remains elusive. The esx-3 gene cluster encoding ESX-3 in both Mycobacterium tuberculosis and Mycobacterium smegmatis has two promoters, suggesting the presence of two transcriptional units. Previous studies indicated that the two promoters only showed a difference in response under acid stress (pH 4.2). This study aimed to study the effect of a mycosin-3 deletion on the physiology of M. smegmatis and to assess the promoter activities in wildtype, mycosin-3 mutant and complementation strains. RESULTS The gene mycP 3 was deleted from wildtype M. smegmatis via homologous recombination. The mycP 3 gene was complemented in the deletion mutant using each of the two intrinsic promoters from the M. smegmatis esx-3 gene cluster. The four strains were compared in term of bacterial growth and intracellular iron content. The two promoter activities were assessed under iron-rich, iron-deprived and iron-rescued conditions by assessing the mycP 3 expression level. Although the mycP 3 gene deletion did not significantly impact bacterial growth or intracellular iron levels in comparison to the wild-type and complemented strains, the two esx-3 promoters were shown to respond inversely to iron deprivation and iron rescue. CONCLUSION This finding correlates with the previously published data that the first promoter upstream of msmeg0615, is upregulated under low iron levels but downregulated under high iron levels. In addition, the second promoter, upstream of msmeg0620, behaves in an inverse fashion to the first promoter implying that the genes downstream may have additional roles when the iron levels are high.
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Affiliation(s)
- Zhuo Fang
- DST/NRF Centre of Excellence in Biomedical Tuberculosis Research, US/MRC Centre for Molecular and Cellular Biology, Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, University of Stellenbosch, Francie van Zijl Drive, Tygerberg, 7505 South Africa
| | - Mae Newton-Foot
- Division of Medical Microbiology, Department of Pathology, Faculty of Medicine and Health Sciences, University of Stellenbosch, Tygerberg, South Africa
- National Health Laboratory Services, Tygerberg Hospital, Francie van Zijl Drive, Tygerberg, 7505 South Africa
| | - Samantha Leigh Sampson
- DST/NRF Centre of Excellence in Biomedical Tuberculosis Research, US/MRC Centre for Molecular and Cellular Biology, Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, University of Stellenbosch, Francie van Zijl Drive, Tygerberg, 7505 South Africa
| | - Nicolaas Claudius Gey van Pittius
- DST/NRF Centre of Excellence in Biomedical Tuberculosis Research, US/MRC Centre for Molecular and Cellular Biology, Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, University of Stellenbosch, Francie van Zijl Drive, Tygerberg, 7505 South Africa
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McLean KJ, Munro AW. Drug targeting of heme proteins in Mycobacterium tuberculosis. Drug Discov Today 2016; 22:566-575. [PMID: 27856345 DOI: 10.1016/j.drudis.2016.11.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Revised: 10/28/2016] [Accepted: 11/02/2016] [Indexed: 01/08/2023]
Abstract
TB, caused by the human pathogen Mycobacterium tuberculosis (Mtb), causes more deaths than any other infectious disease. Iron is crucial for Mtb to infect the host and to sustain infection, with Mtb encoding large numbers of iron-binding proteins. Many of these are hemoproteins with key roles, including defense against oxidative stress, cellular signaling and regulation, host cholesterol metabolism, and respiratory processes. Various heme enzymes in Mtb are validated drug targets and/or products of genes essential for bacterial viability or survival in the host. Here, we review the structure, function, and druggability of key Mtb heme enzymes and strategies used for their inhibition.
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Affiliation(s)
- Kirsty J McLean
- School of Chemistry, The University of Manchester, Manchester Institute of Biotechnology, 131 Princess Street, Manchester M1 7DN, UK
| | - Andrew W Munro
- School of Chemistry, The University of Manchester, Manchester Institute of Biotechnology, 131 Princess Street, Manchester M1 7DN, UK.
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Pharmacological Inhibition of Host Heme Oxygenase-1 Suppresses Mycobacterium tuberculosis Infection In Vivo by a Mechanism Dependent on T Lymphocytes. mBio 2016; 7:mBio.01675-16. [PMID: 27795400 PMCID: PMC5080384 DOI: 10.1128/mbio.01675-16] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Heme oxygenase-1 (HO-1) is a stress response antioxidant enzyme which catalyzes the degradation of heme released during inflammation. HO-1 expression is upregulated in both experimental and human Mycobacterium tuberculosis infection, and in patients it is a biomarker of active disease. Whether the enzyme plays a protective versus pathogenic role in tuberculosis has been the subject of debate. To address this controversy, we administered tin protoporphyrin IX (SnPPIX), a well-characterized HO-1 enzymatic inhibitor, to mice during acute M. tuberculosis infection. These SnPPIX-treated animals displayed a substantial reduction in pulmonary bacterial loads comparable to that achieved following conventional antibiotic therapy. Moreover, when administered adjunctively with antimycobacterial drugs, the HO-1 inhibitor markedly enhanced and accelerated pathogen clearance. Interestingly, both the pulmonary induction of HO-1 expression and the efficacy of SnPPIX treatment in reducing bacterial burden were dependent on the presence of host T lymphocytes. Although M. tuberculosis expresses its own heme-degrading enzyme, SnPPIX failed to inhibit its enzymatic activity or significantly restrict bacterial growth in liquid culture. Together, the above findings reveal mammalian HO-1 as a potential target for host-directed monotherapy and adjunctive therapy of tuberculosis and identify the immune response as a critical regulator of this function. There is no reliable vaccine against tuberculosis (TB), and conventional antibiotic therapy is administered over at least 6 months. This prolonged treatment period can lead to noncompliance resulting in relapsed infection as well as the emergence of multidrug resistance. Thus, there is an urgent need for improved therapeutic regimens that can more rapidly and efficiently control M. tuberculosis in infected patients. Here, we describe a potential strategy for treating TB based on pharmacological inhibition of the host heme-degrading enzyme HO-1. This approach results in significantly reduced bacterial burdens in mice, and when administered in conjunction with conventional antibiotic therapy, leads to faster, more effective pathogen clearance without detectable direct effects on the mycobacteria themselves. Interestingly, the effects of HO-1 inhibition on M. tuberculosis infection in vivo are dependent on the presence of an intact host immune system. These observations establish mammalian HO-1 as a potential target for host-directed therapy of TB.
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Iron Homeostasis in Mycobacterium tuberculosis: Mechanistic Insights into Siderophore-Mediated Iron Uptake. J Bacteriol 2016; 198:2399-409. [PMID: 27402628 DOI: 10.1128/jb.00359-16] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Mycobacterium tuberculosis requires iron for normal growth but faces a limitation of the metal ion due to its low solubility at biological pH and the withholding of iron by the mammalian host. The pathogen expresses the Fe(3+)-specific siderophores mycobactin and carboxymycobactin to chelate the metal ion from insoluble iron and the host proteins transferrin, lactoferrin, and ferritin. Siderophore-mediated iron uptake is essential for the survival of M. tuberculosis, as knockout mutants, which were defective in siderophore synthesis or uptake, failed to survive in low-iron medium and inside macrophages. But as excess iron is toxic due to its catalytic role in the generation of free radicals, regulation of iron uptake is necessary to maintain optimal levels of intracellular iron. The focus of this review is to present a comprehensive overview of iron homeostasis in M. tuberculosis that is discussed in the context of mycobactin biosynthesis, transport of iron across the mycobacterial cell envelope, and storage of excess iron. The clinical significance of the serum iron status and the expression of the iron-regulated protein HupB in tuberculosis (TB) patients is presented here, highlighting the potential of HupB as a marker, notably in extrapulmonary TB cases.
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Role of Metal-Dependent Regulation of ESX-3 Secretion in Intracellular Survival of Mycobacterium tuberculosis. Infect Immun 2016; 84:2255-2263. [PMID: 27245412 DOI: 10.1128/iai.00197-16] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 05/19/2016] [Indexed: 12/31/2022] Open
Abstract
More people die every year from Mycobacterium tuberculosis infection than from infection by any other bacterial pathogen. Type VII secretion systems (T7SS) are used by both environmental and pathogenic mycobacteria to secrete proteins across their complex cell envelope. In the nonpathogen Mycobacterium smegmatis, the ESX-1 T7SS plays a role in conjugation, and the ESX-3 T7SS is involved in metal homeostasis. In M. tuberculosis, these secretion systems have taken on roles in virulence, and they also are targets of the host immune response. ESX-3 secretes a heterodimer composed of EsxG (TB9.8) and EsxH (TB10.4), which impairs phagosome maturation in macrophages and is essential for virulence in mice. Given the importance of EsxG and EsxH during infection, we examined their regulation. With M. tuberculosis, the secretion of EsxG and EsxH was regulated in response to iron and zinc, in accordance with the previously described transcriptional response of the esx-3 locus to these metals. While iron regulated the esx-3 expression in both M. tuberculosis and M. smegmatis, there is a significant difference in the dynamics of this regulation. In M. smegmatis, the esx-3 locus behaved like other iron-regulated genes such as mbtB In M. tuberculosis, both iron and zinc modestly repressed esx-3 expression. Diminished secretion of EsxG and EsxH in response to these metals altered the interaction of M. tuberculosis with macrophages, leading to impaired intracellular M. tuberculosis survival. Our findings detail the regulatory differences of esx-3 in M. tuberculosis and M. smegmatis and demonstrate the importance of metal-dependent regulation of ESX-3 for virulence in M. tuberculosis.
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Krajczyk A, Zeidler J, Januszczyk P, Dawadi S, Boshoff HI, Barry CE, Ostrowski T, Aldrich CC. 2-Aryl-8-aza-3-deazaadenosine analogues of 5'-O-[N-(salicyl)sulfamoyl]adenosine: Nucleoside antibiotics that block siderophore biosynthesis in Mycobacterium tuberculosis. Bioorg Med Chem 2016; 24:3133-43. [PMID: 27265685 DOI: 10.1016/j.bmc.2016.05.037] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 05/17/2016] [Accepted: 05/19/2016] [Indexed: 11/16/2022]
Abstract
A series of 5'-O-[N-(salicyl)sulfamoyl]-2-aryl-8-aza-3-deazaadenosines were designed to block mycobactin biosynthesis in Mycobacterium tuberculosis (Mtb) through inhibition of the essential adenylating enzyme MbtA. The synthesis of the 2-aryl-8-aza-3-deazaadenosine nucleosides featured sequential copper-free palladium-catalyzed Sonogashira coupling of a precursor 4-cyano-5-iodo-1,2,3-triazolonucleoside with terminal alkynes and a Minakawa-Matsuda annulation reaction. These modified nucleosides were shown to inhibit MbtA with apparent Ki values ranging from 6.1 to 25nM and to inhibit Mtb growth under iron-deficient conditions with minimum inhibitory concentrations ranging from 12.5 to >50μM.
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Affiliation(s)
- Anna Krajczyk
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
| | - Joanna Zeidler
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
| | - Piotr Januszczyk
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
| | - Surendra Dawadi
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN 55455, USA
| | - Helena I Boshoff
- Tuberculosis Research Section, National Institute of Allergy and Infectious Diseases, Bethesda, MD 20892, USA
| | - Clifton E Barry
- Tuberculosis Research Section, National Institute of Allergy and Infectious Diseases, Bethesda, MD 20892, USA
| | - Tomasz Ostrowski
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland.
| | - Courtney C Aldrich
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN 55455, USA.
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Ferreira D, Seca AML, C G A D, Silva AMS. Targeting human pathogenic bacteria by siderophores: A proteomics review. J Proteomics 2016; 145:153-166. [PMID: 27109355 DOI: 10.1016/j.jprot.2016.04.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 04/03/2016] [Accepted: 04/12/2016] [Indexed: 12/12/2022]
Abstract
UNLABELLED Human bacterial infections are still a major public health problem throughout the world. Therefore it is fundamental to understand how pathogenic bacteria interact with their human host and to develop more advanced drugs or vaccines in response to the increasing bacterial resistance. Since iron is essential to bacterial survival and growth inside the host tissues, these microorganisms have developed highly efficient iron-acquisition systems; the most common one involves the secretion of iron chelators into the extracellular environment, known as siderophores, and the corresponding siderophore-membrane receptors or transporters responsible for the iron uptake. In the past few decades, several biochemical methods and genetic screens have been employed to track down and identify these iron-scavenging molecules. However, compared with the previous "static" approaches, proteomic identification is revealing far more molecules through full protein mapping and becoming more rapid and selective, leading the scientific and medical community to consider standardizing proteomic tools for clinical biomarker detection of bacterial infectious diseases. In this review, we focus on human pathogenic Gram-negative bacteria and discuss the importance of siderophores in their virulence and the available proteomic strategies to identify siderophore-related proteins and their expression level under different growth conditions. The promising use of siderophore antibiotics to overcome bacterial resistance and the future of proteomics in the routine clinical care are also mentioned. SIGNIFICANCE Proteomic strategies to identify siderophore-related proteins and their expression level can be helpful to control and/or find a cure of infectious deseases especially if related with multidrug resistance. Siderophores are low-molecular-weight compounds produced by bacteria which can become clinical biomarkers and/or antibiotics used mainly in "Trojan horse" type strategies. Due to the above mention we think that the promising use of siderophore to overcome bacterial resistance and the future of proteomics in the routine clinical care is a hot topic that should be discussed.
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Affiliation(s)
- Daniela Ferreira
- Department of Chemistry & Organic Chemistry, Natural Products and Food Stuffs (QOPNA), University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
| | - Ana M L Seca
- Department of Chemistry & Organic Chemistry, Natural Products and Food Stuffs (QOPNA), University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal; Department of Technologic Sciences and Development, University of Azores, Rua Mãe de Deus, 9501-801 Ponta Delgada, Azores, Portugal
| | - Diana C G A
- Department of Chemistry & Organic Chemistry, Natural Products and Food Stuffs (QOPNA), University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal.
| | - Artur M S Silva
- Department of Chemistry & Organic Chemistry, Natural Products and Food Stuffs (QOPNA), University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
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Expression and production of soluble Mycobacterium tuberculosis H37Rv mycosin-3. Biochem Biophys Rep 2016; 5:448-452. [PMID: 28955852 PMCID: PMC5600315 DOI: 10.1016/j.bbrep.2016.02.005] [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: 12/15/2015] [Revised: 02/03/2016] [Accepted: 02/04/2016] [Indexed: 11/29/2022] Open
Abstract
Mycobacteria encode five type VII secretion system (T7SS) or ESX for nutrient acquisition and virulence. Mycosins are membrane-anchored components of ESX with serine protease activity but an unidentified substrate range. Establishing the substrate specificity of individual mycosins will help to elucidate individual ESX functions. Mycosin-1 and -3 orthologues from two environmental mycobacterial species, Mycobacterium smegmatis and Mycobacterium thermoresistibile, have been heterologously produced, but mycosins from Mycobacterium tuberculosis (Mtb) remain to be studied. Here we describe the successful production of Mtb mycosin-3 as a first step in investigating its structure and function. Production of soluble mycosin-3 from Mtb H37Rv. Soluble mycosin-3 was produced in E. coli strain Arctic Express. Soluble mycosin-3 without its N-terminal extension region was produced.
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Iron Deprivation Affects Drug Susceptibilities of Mycobacteria Targeting Membrane Integrity. J Pathog 2015; 2015:938523. [PMID: 26779346 PMCID: PMC4686683 DOI: 10.1155/2015/938523] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 11/19/2015] [Accepted: 11/23/2015] [Indexed: 12/28/2022] Open
Abstract
Multidrug resistance (MDR) acquired by Mycobacterium tuberculosis (MTB) through continuous deployment of antitubercular drugs warrants immediate search for novel targets and mechanisms. The ability of MTB to sense and become accustomed to changes in the host is essential for survival and confers the basis of infection. A crucial condition that MTB must surmount is iron limitation, during the establishment of infection, since iron is required by both bacteria and humans. This study focuses on how iron deprivation affects drug susceptibilities of known anti-TB drugs in Mycobacterium smegmatis, a "surrogate of MTB." We showed that iron deprivation leads to enhanced potency of most commonly used first line anti-TB drugs that could be reverted upon iron supplementation. We explored that membrane homeostasis is disrupted upon iron deprivation as revealed by enhanced membrane permeability and hypersensitivity to membrane perturbing agent leading to increased passive diffusion of drug and TEM images showing detectable differences in cell envelope thickness. Furthermore, iron seems to be indispensable to sustain genotoxic stress suggesting its possible role in DNA repair machinery. Taken together, we for the first time established a link between cellular iron and drug susceptibility of mycobacteria suggesting iron as novel determinant to combat MDR.
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Ascenzi P, di Masi A, Leboffe L, Frangipani E, Nardini M, Verde C, Visca P. Structural Biology of Bacterial Haemophores. Adv Microb Physiol 2015; 67:127-76. [PMID: 26616517 DOI: 10.1016/bs.ampbs.2015.09.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Iron plays a key role in a wide range of metabolic and signalling functions representing an essential nutrient for almost all forms of life. However, the ferric form is hardly soluble, whereas the ferrous form is highly toxic. Thus, in biological fluids, most of the iron is sequestered in iron- or haem-binding proteins and the level of free iron is low, making haem and iron acquisition a challenge for pathogenic bacteria during infections. Although toxic to the host, free haem is a major and readily available source of iron for several pathogenic microorganisms. Both Gram-positive and Gram-negative bacteria have developed several strategies to acquire free haem-Fe and protein-bound haem-Fe. Haemophores are a class of secreted and cell surface-exposed proteins promoting free-haem uptake, haem extraction from host haem proteins, and haem presentation to specific outer-membrane receptors that internalize the metal-porphyrins. Here, structural biology of bacterial haemophores is reviewed focusing on haem acquisition, haem internalization, and haem-degrading systems.
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Affiliation(s)
- Paolo Ascenzi
- Laboratorio Interdipartimentale di Microscopia Elettronica, Università Roma Tre, Roma, Italy; Istituto di Bioscienze e BioRisorse, Consiglio Nazionale delle Ricerche, Napoli, Italy.
| | | | - Loris Leboffe
- Dipartimento di Scienze, Università Roma Tre, Roma, Italy
| | | | - Marco Nardini
- Dipartimento di Bioscienze, Università di Milano, Milano, Italy
| | - Cinzia Verde
- Istituto di Bioscienze e BioRisorse, Consiglio Nazionale delle Ricerche, Napoli, Italy; Dipartimento di Scienze, Università Roma Tre, Roma, Italy
| | - Paolo Visca
- Dipartimento di Scienze, Università Roma Tre, Roma, Italy
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