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Kumar C, Shrivastava K, Singh A, Chauhan V, Giri A, Gupta S, Sharma NK, Bose M, Sharma S, Varma-Basil M. Expression of mammalian cell entry genes in clinical isolates of M. tuberculosis and the cell entry potential and immunological reactivity of the Rv0590A protein. Med Microbiol Immunol 2023; 212:407-419. [PMID: 37787822 DOI: 10.1007/s00430-023-00781-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 08/31/2023] [Indexed: 10/04/2023]
Abstract
Mammalian cell entry (mce) operons play a vital role in cell invasion and survival of M. tuberculosis. Of the mce genes, the function of Rv0590A is still unknown. The present study was performed to investigate the function and immunogenic properties of the protein Rv0590A. Human leukemia monocytic cell line (THP-1) derived macrophages were infected with M. tuberculosis H37Rv at 3, 6, and 24 h of infection. The maximum colony forming units (CFU) were observed at 6 h (p < 0.005), followed by 3 h after infection. M. tuberculosis H37Rv and clinical isolates representative of Delhi/CAS, EAI, Beijing, Haarlem and Euro-American-superlineage were included in the study for expression analysis of mce1A, mce2A, mce3A, mce4A, and Rv0590A genes. Maximum upregulation of all mce genes was observed at 3 h of infection. All the five clinical isolates and H37Rv upregulated Rv0590A at various time points. Macrophage infection with M. tuberculosis H37Rv-overexpressing Rv0590A gene showed higher intracellular CFU as compared to that of wild-type H37Rv. Further, purified Rv0590A protein stimulated the production of TNFα, IFNγ, and IL-10 in macrophages. Thus, Rv0590A was found to be involved in cell invasion and showed good immunological response.
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Affiliation(s)
- Chanchal Kumar
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, 110007, India
| | - Kamal Shrivastava
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, 110007, India
| | - Anupriya Singh
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, 110007, India
| | - Varsha Chauhan
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, 110007, India
- Maharshi Dayanand University, Rohtak, Haryana, India
| | - Astha Giri
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, 110007, India
- Deshbandhu College, University of Delhi, Delhi, India
| | - Shraddha Gupta
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, 110007, India
| | - Naresh Kumar Sharma
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, 110007, India
- University of Manitoba, Winnipeg, MB, Canada
| | - Mridula Bose
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, 110007, India
| | - Sadhna Sharma
- Department of Zoology, Miranda House, University of Delhi, Delhi, 110007, India
| | - Mandira Varma-Basil
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, 110007, India.
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Maity D, Singh D, Bandhu A. Mce1R of Mycobacterium tuberculosis prefers long-chain fatty acids as specific ligands: a computational study. Mol Divers 2023; 27:2523-2543. [PMID: 36385433 DOI: 10.1007/s11030-022-10566-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Accepted: 11/04/2022] [Indexed: 11/17/2022]
Abstract
The mce1 operon of Mycobacterium tuberculosis, which codes the Mce1 transporter, facilitates the transport of fatty acids. Fatty acids are one of the major sources for carbon and energy for the pathogen during its intracellular survival and pathogenicity. The mce1 operon is transcriptionally regulated by Mce1R, a VanR-type regulator, which could bind specific ligands and control the expression of the mce1 operon accordingly. This work reports computational identification of Mce1R-specific ligands. Initially by employing cavity similarity search algorithm by the ProBis server, the cavities of the proteins similar to that of Mce1R and the bound ligands were identified from which fatty acids were selected as the potential ligands. From the earlier-generated monomeric structure, the dimeric structure of Mce1R was then modeled by the GalaxyHomomer server and validated computationally to use in molecular docking and molecular dynamics simulation analysis. The fatty acid ligands were found to dock within the cavity of Mce1R and the docked complexes were subjected to molecular dynamics simulation to explore their stabilities and other dynamic properties. The data suggest that Mce1R preferably binds to long-chain fatty acids and undergoes distinct structural changes upon binding.
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Affiliation(s)
- Dipanwita Maity
- Department of Biotechnology, National Institute of Technology Warangal, Warangal, Telangana, 506004, India
| | - Dheeraj Singh
- Department of Biotechnology, National Institute of Technology Warangal, Warangal, Telangana, 506004, India
| | - Amitava Bandhu
- Department of Biotechnology, National Institute of Technology Warangal, Warangal, Telangana, 506004, India.
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3
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Renau-Mínguez C, Herrero-Abadía P, Ruiz-Rodriguez P, Sentandreu V, Torrents E, Chiner-Oms Á, Torres-Puente M, Comas I, Julián E, Coscolla M. Genomic analysis of Mycobacterium brumae sustains its nonpathogenic and immunogenic phenotype. Front Microbiol 2023; 13:982679. [PMID: 36687580 PMCID: PMC9850167 DOI: 10.3389/fmicb.2022.982679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 12/06/2022] [Indexed: 01/07/2023] Open
Abstract
Mycobacterium brumae is a rapid-growing, non-pathogenic Mycobacterium species, originally isolated from environmental and human samples in Barcelona, Spain. Mycobacterium brumae is not pathogenic and it's in vitro phenotype and immunogenic properties have been well characterized. However, the knowledge of its underlying genetic composition is still incomplete. In this study, we first describe the 4 Mb genome of the M. brumae type strain ATCC 51384T assembling PacBio reads, and second, we assess the low intraspecies variability by comparing the type strain with Illumina reads from three additional strains. Mycobacterium brumae genome is composed of a circular chromosome with a high GC content of 69.2% and containing 3,791 CDSs, 97 pseudogenes, one prophage and no CRISPR loci. Mycobacterium brumae has shown no pathogenic potential in in vivo experiments, and our genomic analysis confirms its phylogenetic position with other non-pathogenic and rapid growing mycobacteria. Accordingly, we determined the absence of virulence-related genes, such as ESX-1 locus and most PE/PPE genes, among others. Although the immunogenic potential of M. brumae was proved to be as high as Mycobacterium bovis BCG, the only mycobacteria licensed to treat cancer, the genomic content of M. tuberculosis T cell and B cell antigens in M. brumae genome is considerably lower than those antigens present in M. bovis BCG genome. Overall, this work provides relevant genomic data on one of the species of the mycobacterial genus with high therapeutic potential.
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Affiliation(s)
| | - Paula Herrero-Abadía
- Genetics and Microbiology Department, Faculty of Biosciences, Autonomous University of Barcelona, Barcelona, Spain
| | | | - Vicente Sentandreu
- Genomics Unit, Central Service for Experimental Research (SCSIE), University of Valencia, Burjassot, Spain
| | - Eduard Torrents
- Bacterial Infections and Antimicrobial Therapies Group, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain,Microbiology Section, Department of Genetics, Microbiology, and Statistics, Biology Faculty, Universitat de Barcelona, Barcelona, Spain
| | | | | | - Iñaki Comas
- Instituto de Biomedicina de Valencia (IBV), CSIC, Valencia, Spain
| | - Esther Julián
- Genetics and Microbiology Department, Faculty of Biosciences, Autonomous University of Barcelona, Barcelona, Spain,Esther Julián, ✉
| | - Mireia Coscolla
- I2SysBio, University of Valencia-FISABIO Joint Unit, Paterna, Spain,*Correspondence: Mireia Coscolla, ✉
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4
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Ma W, Jin W, He X, Sun Y, Yin H, Wang Z, Shi S. Mycobacterium tuberculosis Induced Osteoblast Dysregulation Involved in Bone Destruction in Spinal Tuberculosis. Front Cell Infect Microbiol 2022; 12:780272. [PMID: 35463641 PMCID: PMC9019588 DOI: 10.3389/fcimb.2022.780272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 02/21/2022] [Indexed: 11/24/2022] Open
Abstract
Disturbance of bone homeostasis caused by Mycobacterium tuberculosis (Mtb) is a key clinical manifestation in spinal tuberculosis (TB). However, the complete mechanism of this process has not been established, and an effective treatment target does not exist. Increasing evidence shows that abnormal osteoclastogenesis triggered by an imbalance of the receptor activator of NF-κB ligand (RANKL)/osteoprotegerin (OPG) axis may play a key role in the disturbance of bone homeostasis. Previous studies reported that RANKL is strongly activated in patients with spinal TB; however, the OPG levels in these patients were not investigated in previous studies. In this study, we investigated the OPG levels in patients with spinal TB and the dysregulation of osteoblasts caused by Mtb infection. Inhibition of the Mce4a gene of Mtb by an antisense locked nucleic acid (LNA) gapmer (Mce4a-ASO) was also investigated. Analysis of the serum OPG levels in clinical samples showed that the OPG levels were significantly decreased in patients with spinal TB compared to those in the group of non-TB patients. The internalization of Mtb in osteoblasts, the known major source of OPG, was investigated using the green fluorescent protein (GFP)-labeled Mycobacterium strain H37Ra (H37RaGFP). The cell-associated fluorescence measurements showed that Mtb can efficiently enter osteoblast cells. In addition, Mtb infection caused a dose-dependent increase of the CD40 mRNA expression and cytokine (interleukin 6, IL-6) secretion in osteoblast cells. Ligation of CD40 by soluble CD154 reversed the increased secretion of IL-6. This means that the induced CD40 is functional. Considering that the interaction between CD154-expressing T lymphocytes and bone-forming osteoblast cells plays a pivotal role in bone homeostasis, the CD40 molecule might be a strong candidate for mediating the target for treatment of bone destruction in spinal TB. Additionally, we also found that Mce4a-ASO could dose-dependently inhibit the Mce4a gene of Mtb and reverse the decreased secretion of IL-6 and the impaired secretion of OPG caused by Mtb infection of osteoblast cells. Taken together, the current finding provides breakthrough ideas for the development of therapeutic agents for spinal TB.
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Affiliation(s)
- Wenxin Ma
- Department of Spine Surgery, General Hospital of Ningxia Medical University, Ningxia, China
| | - Weidong Jin
- Department of Spine Surgery, General Hospital of Ningxia Medical University, Ningxia, China
| | - Xijing He
- Department of Spine Surgery, Xi’an International Medical Center Hospital Affiliated to Northwest University, Shaanxi, China
| | - Yuhang Sun
- Department of Orthopedics, Liaocheng Hospital of Traditional Chinese Medicine, Liaocheng, China
| | - Huquan Yin
- Department of Biochemistry, Inteliex Biotechnology Corp, Tampa, FL, United States
| | - Zili Wang
- Department of Spine Surgery, General Hospital of Ningxia Medical University, Ningxia, China
- Department of Spine Surgery, Xi’an International Medical Center Hospital Affiliated to Northwest University, Shaanxi, China
- *Correspondence: Zili Wang, ; Shiyuan Shi,
| | - Shiyuan Shi
- Department of Orthopedics, Hangzhou Chest Hospital affiliated to Zhejiang University Medical College, Zhejiang, China
- *Correspondence: Zili Wang, ; Shiyuan Shi,
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Wei Y, Chen T, Yang W, Li H, Fang C, Liu Q, Chen Y, Mei Q. Detection of a novel antigen for Crohn's disease. Scand J Gastroenterol 2021; 56:1427-1433. [PMID: 34487462 DOI: 10.1080/00365521.2021.1973088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND AND AIMS Accurate serological assays are desirable for the diagnosis of inflammatory bowel disease (IBD). We identify an antigen-like substance called Crohn's disease (CD) antibody binding polypeptide (CABP). As a serological marker, anti-CABP may contribute to the diagnosis of IBD. The present study aims to evaluate the clinical role of anti-CABP as a serological antibody for IBD. METHODS Using enzyme-linked immunosorbent assay (ELISA), serum anti-CABP, anti-Saccharomyces cerevisiae antibody (ASCA) and perinuclear anti-neutrophil cytoplasmic antibody (pANCA), titers were tested in 168 CD patients, 123 ulcerative colitis (UC) patients and 170 controls. The correlation between serum antibody and clinical characteristics was investigated. The diagnostic potential of the anti-CABP was evaluated by receiver operating characteristic (ROC) analysis. RESULTS The titers of anti-CABP (IgA or IgG) and ASCA IgG of CD patients were significantly higher than non-CD group (all p < .01). In the differential diagnosis of CD and non-CD, anti-CABP IgA revealed an area under the curve (AUC) of 0.706 and anti-CABP IgG demonstrated an AUC of 0.788. As an individual antibody, anti-CABP could effectively distinguish CD from non-CD (AUC 0.816), and the diagnostic efficacy was better than that of ASCA (AUC 0.680). The combined use of anti-CABP, ASCA and pANCA significantly improved the diagnostic value (AUC 0.857). Anti-CABP positive rates were associated with perianal lesions and disease location in CD patients (both p < .05). CONCLUSIONS Our results suggested that anti-CABP could be used as a serological marker to assist the diagnosis of CD. CLINICAL TRIAL REGISTRATION This trial is registered with clinical trial registration unique identifier ChiCTR2000037094.
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Affiliation(s)
- Yarong Wei
- Department of Gastroenterology, the Key Laboratory of Digestive Diseases of Anhui Province, the First Affiliated Hospital of Anhui Medical University, Hefei, China
| | | | - Wu Yang
- Shanxi Ruihao Biotechnology Co. LTD, Taiyuan, China
| | - Huihui Li
- Department of Gastroenterology, the Key Laboratory of Digestive Diseases of Anhui Province, the First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Chen Fang
- Department of Gastroenterology, the Key Laboratory of Digestive Diseases of Anhui Province, the First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Qiuyuan Liu
- Department of Gastroenterology, the Key Laboratory of Digestive Diseases of Anhui Province, the First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Yonghao Chen
- Department of Gastroenterology, the Key Laboratory of Digestive Diseases of Anhui Province, the First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Qiao Mei
- Department of Gastroenterology, the Key Laboratory of Digestive Diseases of Anhui Province, the First Affiliated Hospital of Anhui Medical University, Hefei, China
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6
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Asthana P, Singh D, Pedersen JS, Hynönen MJ, Sulu R, Murthy AV, Laitaoja M, Jänis J, Riley LW, Venkatesan R. Structural insights into the substrate-binding proteins Mce1A and Mce4A from Mycobacterium tuberculosis. IUCRJ 2021; 8:757-774. [PMID: 34584737 PMCID: PMC8420772 DOI: 10.1107/s2052252521006199] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 06/15/2021] [Indexed: 05/28/2023]
Abstract
Mycobacterium tuberculosis (Mtb), which is responsible for more than a million deaths annually, uses lipids as the source of carbon and energy for its survival in the latent phase of infection. Mtb cannot synthesize all of the lipid molecules required for its growth and pathogenicity. Therefore, it relies on transporters such as the mammalian cell entry (Mce) complexes to import lipids from the host across the cell wall. Despite their importance for the survival and pathogenicity of Mtb, information on the structural properties of these proteins is not yet available. Each of the four Mce complexes in Mtb (Mce1-4) comprises six substrate-binding proteins (SBPs; MceA-F), each of which contains four conserved domains (N-terminal transmembrane, MCE, helical and C-terminal unstructured tail domains). Here, the properties of the various domains of Mtb Mce1A and Mce4A, which are involved in the import of mycolic/fatty acids and cholesterol, respectively, are reported. In the crystal structure of the MCE domain of Mce4A (MtMce4A39-140) a domain-swapped conformation is observed, whereas solution studies, including small-angle X-ray scattering (SAXS), indicate that all Mce1A and Mce4A domains are predominantly monomeric. Further, structural comparisons show interesting differences from the bacterial homologs MlaD, PqiB and LetB, which form homohexamers when assembled as functional transporter complexes. These data, and the fact that there are six SBPs in each Mtb mce operon, suggest that the MceA-F SBPs from Mce1-4 may form heterohexamers. Also, interestingly, the purification and SAXS analysis showed that the helical domains interact with the detergent micelle, suggesting that when assembled the helical domains of MceA-F may form a hydrophobic pore for lipid transport, as observed in EcPqiB. Overall, these data highlight the unique structural properties of the Mtb Mce SBPs.
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Affiliation(s)
- Pooja Asthana
- Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Dhirendra Singh
- Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Jan Skov Pedersen
- Department of Chemistry and Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus, Denmark
| | - Mikko J. Hynönen
- Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Ramita Sulu
- Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Abhinandan V. Murthy
- Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Mikko Laitaoja
- Department of Chemistry, University of Eastern Finland, Joensuu, Finland
| | - Janne Jänis
- Department of Chemistry, University of Eastern Finland, Joensuu, Finland
| | - Lee W. Riley
- School of Public Health, University of California, Berkeley, California, USA
| | - Rajaram Venkatesan
- Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
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Ma F, Zhou H, Yang Z, Wang C, An Y, Ni L, Liu M, Wang Y, Yu L. Gene expression profile analysis and target gene discovery of Mycobacterium tuberculosis biofilm. Appl Microbiol Biotechnol 2021; 105:5123-5134. [PMID: 34125278 DOI: 10.1007/s00253-021-11361-4] [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: 11/04/2020] [Revised: 04/27/2021] [Accepted: 05/20/2021] [Indexed: 10/21/2022]
Abstract
Tuberculosis (TB) caused by Mycobacterium tuberculosis (M. tuberculosis) is a fatal infectious disease to human health, and the drug tolerance and immune evasion of M. tuberculosis were reported to be related to its biofilm formation; however, the difficulty of M. tuberculosis biofilm culture and its unknown global mechanism impede its further research. Here, we developed a modified in vitro M. tuberculosis biofilm model with shorter culture time. Then we used Illumina RNA-seq technology to determine the global gene expression profile of M. tuberculosis H37Rv biofilms. Over 437 genes are expressed at significantly different levels in biofilm cells than in planktonic cells; among them, 153 were downregulated and 284 were upregulated. Go enrichment analysis and KEGG pathway analysis showed that genes involved in biosynthesis and metabolism of sulfur metabolism, steroid degradation, atrazine degradation, mammalian cell entry protein complex, etc. are involved in M. tuberculosis biofilm cells. Especially, ATP-binding cassette (ABC) transporters Rv1217c and Rv1218c were significantly upregulated in biofilm, whereas efflux pump inhibitors (EPIs) piperine and 1-(1-naphthylmethyl)-piperazine (NMP) inhibited biofilm formation and the expression of the Rv1217c and Rv1218c genes in a concentration-dependent manner, respectively, indicating Rv1217c and Rv1218c are potential target genes of M. tuberculosis biofilm. This study is the first RNA-Seq-based transcriptome profiling of M. tuberculosis biofilms and provides insights into a potential strategy for M. tuberculosis biofilm inhibition. KEY POINTS: • Characterize M. tuberculosis transcriptomes in biofilm cells by RNA-seq. • Inhibit the expression of Rv1217c and Rv1218c repressed biofilm formation.
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Affiliation(s)
- Fangxue Ma
- Key Laboratory for Zoonoses Research, Ministry of Education, Institute of Zoonosis, Department of Infectious Diseases, First Hospital of Jilin University, College of Veterinary Medicine, Jilin University, Changchun, 130062, China
| | - Hong Zhou
- Key Laboratory for Zoonoses Research, Ministry of Education, Institute of Zoonosis, Department of Infectious Diseases, First Hospital of Jilin University, College of Veterinary Medicine, Jilin University, Changchun, 130062, China
| | - Zhiqiang Yang
- Institute of Biomedical Sciences, School of Life Science, Shanxi University, Taiyuan, 030006, China
| | - Chao Wang
- Department of Immunology, Binzhou Medical University, Yantai, 264000, China
| | - Yanan An
- Department of Physiology, Binzhou Medical University, Yantai, 264000, China
| | - Lihui Ni
- Key Laboratory for Zoonoses Research, Ministry of Education, Institute of Zoonosis, Department of Infectious Diseases, First Hospital of Jilin University, College of Veterinary Medicine, Jilin University, Changchun, 130062, China
| | - Mingyuan Liu
- Key Laboratory for Zoonoses Research, Ministry of Education, Institute of Zoonosis, Department of Infectious Diseases, First Hospital of Jilin University, College of Veterinary Medicine, Jilin University, Changchun, 130062, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009, China
| | - Yang Wang
- Key Laboratory for Zoonoses Research, Ministry of Education, Institute of Zoonosis, Department of Infectious Diseases, First Hospital of Jilin University, College of Veterinary Medicine, Jilin University, Changchun, 130062, China.
| | - Lu Yu
- Key Laboratory for Zoonoses Research, Ministry of Education, Institute of Zoonosis, Department of Infectious Diseases, First Hospital of Jilin University, College of Veterinary Medicine, Jilin University, Changchun, 130062, China.
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Madan R, Pandit K, Bhati L, Kumar H, Kumari N, Singh S. Mining the Mycobacterium tuberculosis proteome for identification of potential T-cell epitope based vaccine candidates. Microb Pathog 2021; 157:104996. [PMID: 34044044 DOI: 10.1016/j.micpath.2021.104996] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 05/07/2021] [Accepted: 05/10/2021] [Indexed: 12/22/2022]
Abstract
Identification of protective antigens for designing a high-efficacy tuberculosis vaccine is the need of the hour. Till date only 7% of the Mycobacterium tuberculosis proteome has been explored for discovering antigens capable of activating T-cell responses. Therefore, it becomes crucial to screen the remaining Mycobacterium tuberculosis proteome for more immunodominant T-cell epitopes. An extensive knowledge of the epitopes recognized by our immune system can aid this process of finding potential T cell antigens for development of a better TB vaccine. In the present in-silico study, 237 proteins belonging to the 'virulence, detoxification, and adaptation' category of Mycobacterium tuberculosis proteome were targeted for T-cell epitope screening. 50825 MHC Class I and 49357 MHC Class II epitopes were generated using NetMHC3.4 and IEDB servers respectively and tested for their antigenicity and cytokine stimulation. The highest antigenic epitopes were analyzed for their world population coverage and epitope conservancy. Molecular docking and molecular dynamics simulation studies were performed to corroborate the binding affinities and structural stability of the peptide-MHC complexes. We predicted a total of 3 MHC Class I (ILLKMCWPA, FAVGMNVYV, and SLAGNSAKV) and 7 MHC Class II (DLTIGFFLHIPFPPV, RPDLTIGFFLHIPFP, LTIGFFLHIPFPPVE, VLVFALVVALVYLQF, LVFALVVALVYLQFR, PNLVAARFIQLTPVY, and LVLVFALVVALVYLQ) epitopes that can be promising vaccine candidates. These predicted epitopes belong to 6 distinct proteins: Rv0169 (mce1a), Rv3490 (ostA), Rv3496 (mce4D), Rv1085c, Rv0563 (HtpX), Rv3497c (mce4C). All these proteins are expressed at different stages in the life cycle of Mycobacterium tuberculosis and thus, the predicted epitopes could be employed as candidates for designing a multistage-multiepitopic vaccine.
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Affiliation(s)
- Riya Madan
- Department of Zoology, Hansraj College, University of Delhi, India.
| | - Kushankur Pandit
- Department of Zoology, Hansraj College, University of Delhi, India.
| | - Lavi Bhati
- Department of Zoology, Hansraj College, University of Delhi, India.
| | - Hindesh Kumar
- Department of Zoology, Hansraj College, University of Delhi, India.
| | - Neha Kumari
- Department of Zoology, Hansraj College, University of Delhi, India.
| | - Swati Singh
- Department of Zoology, Hansraj College, University of Delhi, India.
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9
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Molecular Cloning, Purification and Characterization of Mce1R of Mycobacterium tuberculosis. Mol Biotechnol 2021; 63:200-220. [PMID: 33423211 DOI: 10.1007/s12033-020-00293-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/18/2020] [Indexed: 10/22/2022]
Abstract
The mce1 operon of Mycobacterium tuberculosis, important for lipid metabolism/transport, host cell invasion, modulation of host immune response and pathogenicity, is under the transcriptional control of Mce1R. Hence characterizing Mce1R is an important step for novel anti-tuberculosis drug discovery. The present study reports functional and in silico characterization of Mce1R. In this work, we have computationally modeled the structure of Mce1R and have validated the structure by computational and experimental methods. Mce1R has been shown to harbor the canonical VanR-like structure with a flexible N-terminal 'arm', carrying conserved positively charged residues, most likely involved in the operator DNA binding. The mce1R gene has been cloned, expressed, purified and its DNA-binding activity has been measured in vitro. The Kd value for Mce1R-operator DNA interaction has been determined to be 0.35 ± 0.02 µM which implies that Mce1R binds to DNA with moderate affinity compared to the other FCD family of regulators. So far, this is the first report for measuring the DNA-binding affinity of any VanR-type protein. Despite significant sequence similarity at the N-terminal domain, the wHTH motif of Mce1R exhibits poor conservancy of amino acid residues, critical for DNA-binding, thus results in moderate DNA-binding affinity. The N-terminal DNA-binding domain is structurally dynamic while the C-terminal domain showed significant stability and such profile of structural dynamics is most likely to be preserved in the structural orthologs of Mce1R. In addition to this, a cavity has been detected in the C-terminal domain of Mce1R which contains a few conserved residues. Comparison with other FCD family of regulators suggests that most of the conserved residues might be critical for binding to specific ligand. The max pKd value and drug score for the cavity are estimated to be 9.04 and 109 respectively suggesting that the cavity represents a suitable target site for novel anti-tuberculosis drug discovery approaches.
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10
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Vega-Dominguez P, Peterson E, Pan M, Di Maio A, Singh S, Umapathy S, Saini DK, Baliga N, Bhatt A. Biofilms of the non-tuberculous Mycobacterium chelonae form an extracellular matrix and display distinct expression patterns. Cell Surf 2020; 6:100043. [PMID: 32803022 PMCID: PMC7421604 DOI: 10.1016/j.tcsw.2020.100043] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 07/28/2020] [Accepted: 07/29/2020] [Indexed: 12/18/2022] Open
Abstract
Mycobacterium chelonae is an environmental, non-tuberculous mycobacterial species, capable of causing infections in humans. Biofilm formation is a key strategy used by M. chelonae in colonising niches in the environment and in the host. We studied a water-air interface (pellicle) biofilm of M. chelonae using a wide array of approaches to outline the molecular structure and composition of the biofilm. Scanning electron micrographs showed that M. chelonae biofilms produced an extracellular matrix. Using a combination of biochemical analysis, Raman spectroscopy, and fluorescence microscopy, we showed the matrix to consist of proteins, carbohydrates, lipids and eDNA. Glucose was the predominant sugar present in the biofilm matrix, and its relative abundance decreased in late (established) biofilms. RNA-seq analysis of the biofilms showed upregulation of genes involved in redox metabolism. Additionally, genes involved in mycolic acid, other lipid and glyoxylate metabolism were also upregulated in the early biofilms.
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Affiliation(s)
- Perla Vega-Dominguez
- School of Biosciences and Institute of Microbiology and Infection, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | | | - Min Pan
- Institute for Systems Biology, Seattle, WA 98109, USA
| | - Alessandro Di Maio
- School of Biosciences and Institute of Microbiology and Infection, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Saumya Singh
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India
| | - Siva Umapathy
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India
| | - Deepak K. Saini
- Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore 560012, India
| | - Nitin Baliga
- Institute for Systems Biology, Seattle, WA 98109, USA
| | - Apoorva Bhatt
- School of Biosciences and Institute of Microbiology and Infection, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
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11
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Zaychikova MV, Danilenko VN. The Actinobacterial mce Operon: Structure and Functions. BIOLOGY BULLETIN REVIEWS 2020. [PMCID: PMC7709480 DOI: 10.1134/s2079086420060079] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- M. V. Zaychikova
- Vavilov Institute of General Genetics, Russian Academy of Sciences, 117971 Moscow, Russia
| | - V. N. Danilenko
- Vavilov Institute of General Genetics, Russian Academy of Sciences, 117971 Moscow, Russia
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12
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Ji X, Zhang X, Sun L, Hou X, Song J, Tan X, Song H, Qiu X, Li M, Tang L, Han L, Li Z. Mce1C and Mce1D facilitate N. farcinica invasion of host cells and suppress immune responses by inhibiting innate signaling pathways. Sci Rep 2020; 10:14908. [PMID: 32913259 PMCID: PMC7484815 DOI: 10.1038/s41598-020-71860-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 08/06/2020] [Indexed: 11/22/2022] Open
Abstract
The mammalian cell entry (Mce) family of proteins consists of invasin-like membrane-associated proteins. The roles of Mce1C and Mce1D proteins in host–pathogen interactions have not been investigated. In this study, we demonstrate that Mce1C and Mce1D protein is localized in the cell wall fraction of N. farcinica. Both N. farcinica Mce1C and Mce1D proteins are expressed at the level of protein and mRNA and elicit antibody responses during infection. Mce1C and Mce1D facilitate the internalization of Escherichia coli expressing Mce1C protein or latex beads coated with Mce1D protein by HeLa cells, respectively. We further demonstrate that Mce1C and Mce1D can suppress the secretion of the proinflammatory factors TNF-α and IL-6 in macrophages infected with Mycobacterium smegmatis expressing Mce1C or Mce1D and promote the survival of M. smegmatis expressing Mce1C or Mce1D in macrophages. In addition, Mce1C and Mce1D supress the activation of the NF-κB and MAPK signaling pathways by blocking the phosphorylation of AKT, P65, ERK1/2, JNK, or P38 in macrophages. These findings suggest that Mce1C and Mce1D proteins facilitate N. farcinica invasion of HeLa cells and suppress host innate immune responses by manipulating NF-κB and MAPK signaling pathways, which may provide a target for N. farcinica treatment.
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Affiliation(s)
- Xingzhao Ji
- Shandong Academy of Clinical Medicine, Provincial Hospital Affiliated to Shandong First Medical University, Jinan, 250000, China.,State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, 155 Changbai Road Changping District, Beijing, 102206, China
| | - Xiujuan Zhang
- Department of Endocrinology, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China
| | - Lina Sun
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, 155 Changbai Road Changping District, Beijing, 102206, China
| | - Xuexin Hou
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, 155 Changbai Road Changping District, Beijing, 102206, China
| | - Jingdong Song
- National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Xiaoluo Tan
- Chenzhou Center for Disease Control and Prevention, Chenzhou, China
| | - Han Song
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, 155 Changbai Road Changping District, Beijing, 102206, China
| | - Xiaotong Qiu
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, 155 Changbai Road Changping District, Beijing, 102206, China
| | - Minghui Li
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, 155 Changbai Road Changping District, Beijing, 102206, China
| | - Lu Tang
- First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Lichao Han
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, 155 Changbai Road Changping District, Beijing, 102206, China
| | - Zhenjun Li
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, 155 Changbai Road Changping District, Beijing, 102206, China.
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13
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Hemati Z, Derakhshandeh A, Haghkhah M, Chaubey KK, Gupta S, Singh M, Singh SV, Dhama K. Mammalian cell entry operons; novel and major subset candidates for diagnostics with special reference to Mycobacterium avium subspecies paratuberculosis infection. Vet Q 2020; 39:65-75. [PMID: 31282842 PMCID: PMC6830979 DOI: 10.1080/01652176.2019.1641764] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Mammalian cell entry (mce) genes are the components of the mce operon and play a vital role in the entry of Mycobacteria into the mammalian cell and their survival within phagocytes and epithelial cells. Mce operons are present in the DNA of Mycobacteria and translate proteins associated with the invasion and long-term existence of these pathogens in macrophages. The exact mechanism of action of mce genes and their functions are not clear yet. However, with the loss of these genes Mycobacteria lose their pathogenicity. Mycobacterium avium subspecies paratuberculosis (MAP), the etiological agent of Johne’s disease, is the cause of chronic enteritis of animals and significantly affects economic impact on the livestock industry. Since MAP is not inactivated during pasteurization, human population is continuously at the risk of getting exposed to MAP infection through consumption of dairy products. There is need for new candidate genes and/or proteins for developing improved diagnostic assays for the diagnosis of MAP infection and for the control of disease. Increasing evidences showed that expression of mce genes is important for the virulence of MAP. Whole-genome DNA microarray representing MAP revealed that there are 14 large sequence polymorphisms with LSPP12 being the most widely conserved MAP-specific region that included a cluster of six homologs of mce-family involved in lipid metabolism. On the other hand, LSP11 comprising part of mce2 operon was absent in MAP isolates. This review summarizes the advancement of research on mce genes of Mycobacteria with special reference to the MAP infection.
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Affiliation(s)
- Zahra Hemati
- Department of Pathobiology, School of Veterinary Medicine, Shiraz University , Shiraz , Iran
| | - Abdollah Derakhshandeh
- Department of Pathobiology, School of Veterinary Medicine, Shiraz University , Shiraz , Iran
| | - Masoud Haghkhah
- Department of Pathobiology, School of Veterinary Medicine, Shiraz University , Shiraz , Iran
| | - Kundan Kumar Chaubey
- Department of Biotechnology, Institute of Applied Sciences and Humanities, GLA University , Mathura , India
| | - Saurabh Gupta
- Department of Biotechnology, Institute of Applied Sciences and Humanities, GLA University , Mathura , India
| | - Manju Singh
- Department of Biotechnology, Institute of Applied Sciences and Humanities, GLA University , Mathura , India
| | - Shoorvir V Singh
- Department of Biotechnology, Institute of Applied Sciences and Humanities, GLA University , Mathura , India
| | - Kuldeep Dhama
- Department of Pathology, Indian Veterinary Research Institute , Bareilly , India
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14
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Seto S, Morimoto K, Yoshida T, Hiramatsu M, Hijikata M, Nagata T, Kikuchi F, Shiraishi Y, Kurashima A, Keicho N. Proteomic Profiling Reveals the Architecture of Granulomatous Lesions Caused by Tuberculosis and Mycobacterium avium Complex Lung Disease. Front Microbiol 2020; 10:3081. [PMID: 32010116 PMCID: PMC6978656 DOI: 10.3389/fmicb.2019.03081] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 12/20/2019] [Indexed: 12/28/2022] Open
Abstract
Tuberculosis (TB) and Mycobacterium avium complex lung disease (MAC-LD) are both characterized pathologically by granuloma lesions, which are typically composed of a necrotic caseum at the center surrounded by fibrotic cells and lymphocytes. Although the histological characterization of TB and MAC-LD granulomas has been well-documented, their molecular signatures have not been fully evaluated. In this research we applied mass spectrometry-based proteomics combined with laser microdissection to investigate the unique protein markers in human mycobacterial granulomatous lesions. Comparing the protein abundance between caseous and cellular sub-compartments of mycobacterial granulomas, we found distinct differences. Proteins involved in cellular metabolism in transcription and translation were abundant in cellular regions, while in caseous regions proteins related to antimicrobial response accumulated. To investigate the determinants of their heterogeneity, we compared the protein abundance in caseous regions between TB and MAC-LD granulomas. We found that several proteins were significantly abundant in the MAC-LD caseum of which proteomic profiles were different from those of the TB caseum. Immunohistochemistry demonstrated that one of these proteins, Angiogenin, specifically localized to the caseous regions of selected MAC-LD granulomas. We also detected peptides derived from mycobacterial proteins in the granulomas of both diseases. This study provides new insights into the architecture of granulomatous lesions in TB and MAC-LD.
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Affiliation(s)
- Shintaro Seto
- Department of Pathophysiology and Host Defense, Research Institute of Tuberculosis, Japan Anti-Tuberculosis Association, Tokyo, Japan
| | - Kozo Morimoto
- Respiratory Disease Center, Fukujuji Hospital, Japan Anti-Tuberculosis Association, Tokyo, Japan
| | - Tsutomu Yoshida
- Respiratory Disease Center, Fukujuji Hospital, Japan Anti-Tuberculosis Association, Tokyo, Japan
| | - Miyako Hiramatsu
- Respiratory Disease Center, Fukujuji Hospital, Japan Anti-Tuberculosis Association, Tokyo, Japan
| | - Minako Hijikata
- Department of Pathophysiology and Host Defense, Research Institute of Tuberculosis, Japan Anti-Tuberculosis Association, Tokyo, Japan
| | - Toshi Nagata
- Department of Health Science, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Fumihito Kikuchi
- Department of Pathology, Fukujuji Hospital, Japan Anti-Tuberculosis Association, Tokyo, Japan
| | - Yuji Shiraishi
- Respiratory Disease Center, Fukujuji Hospital, Japan Anti-Tuberculosis Association, Tokyo, Japan
| | - Atsuyuki Kurashima
- Respiratory Disease Center, Fukujuji Hospital, Japan Anti-Tuberculosis Association, Tokyo, Japan
| | - Naoto Keicho
- Research Institute of Tuberculosis, Japan Anti-Tuberculosis Association, Tokyo, Japan
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15
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Stamm CE, Pasko BL, Chaisavaneeyakorn S, Franco LH, Nair VR, Weigele BA, Alto NM, Shiloh MU. Screening Mycobacterium tuberculosis Secreted Proteins Identifies Mpt64 as a Eukaryotic Membrane-Binding Bacterial Effector. mSphere 2019; 4:e00354-19. [PMID: 31167949 PMCID: PMC6553557 DOI: 10.1128/msphere.00354-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 05/19/2019] [Indexed: 02/07/2023] Open
Abstract
Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis, is one of the most successful human pathogens. One reason for its success is that Mtb can reside within host macrophages, a cell type that normally functions to phagocytose and destroy infectious bacteria. However, Mtb is able to evade macrophage defenses in order to survive for prolonged periods of time. Many intracellular pathogens secrete virulence factors targeting host membranes and organelles to remodel their intracellular environmental niche. We hypothesized that Mtb secreted proteins that target host membranes are vital for Mtb to adapt to and manipulate the host environment for survival. Thus, we characterized 200 secreted proteins from Mtb for their ability to associate with eukaryotic membranes using a unique temperature-sensitive yeast screen and to manipulate host trafficking pathways using a modified inducible secretion screen. We identified five Mtb secreted proteins that both associated with eukaryotic membranes and altered the host secretory pathway. One of these secreted proteins, Mpt64, localized to the endoplasmic reticulum during Mtb infection of murine and human macrophages and impaired the unfolded protein response in macrophages. These data highlight the importance of secreted proteins in Mtb pathogenesis and provide a basis for further investigation into their molecular mechanisms.IMPORTANCE Advances have been made to identify secreted proteins of Mycobacterium tuberculosis during animal infections. These data, combined with transposon screens identifying genes important for M. tuberculosis virulence, have generated a vast resource of potential M. tuberculosis virulence proteins. However, the function of many of these proteins in M. tuberculosis pathogenesis remains elusive. We have integrated three cell biological screens to characterize nearly 200 M. tuberculosis secreted proteins for eukaryotic membrane binding, host subcellular localization, and interactions with host vesicular trafficking. In addition, we observed the localization of one secreted protein, Mpt64, to the endoplasmic reticulum (ER) during M. tuberculosis infection of macrophages. Interestingly, although Mpt64 is exported by the Sec pathway, its delivery into host cells was dependent upon the action of the type VII secretion system. Finally, we observed that Mpt64 impairs the ER-mediated unfolded protein response in macrophages.
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Affiliation(s)
- Chelsea E Stamm
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Breanna L Pasko
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Sujittra Chaisavaneeyakorn
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Luis H Franco
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Center for Autophagy Research, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Vidhya R Nair
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Bethany A Weigele
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Neal M Alto
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Michael U Shiloh
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
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16
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Khan S, Khan P, Hassan MI, Ahmad F, Islam A. Protein stability: Determination of structure and stability of the transmembrane protein Mce4A from M. tuberculosis in membrane-like environment. Int J Biol Macromol 2019; 126:488-495. [DOI: 10.1016/j.ijbiomac.2018.12.183] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 12/08/2018] [Accepted: 12/21/2018] [Indexed: 10/27/2022]
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17
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Cell wall enrichment unveils proteomic changes in the cell wall during treatment of Mycobacterium smegmatis with sub-lethal concentrations of rifampicin. J Proteomics 2019; 191:166-179. [DOI: 10.1016/j.jprot.2018.02.019] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 02/02/2018] [Accepted: 02/10/2018] [Indexed: 12/21/2022]
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18
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Abhishek S, Saikia UN, Gupta A, Bansal R, Gupta V, Singh N, Laal S, Verma I. Transcriptional Profile of Mycobacterium tuberculosis in an in vitro Model of Intraocular Tuberculosis. Front Cell Infect Microbiol 2018; 8:330. [PMID: 30333960 PMCID: PMC6175983 DOI: 10.3389/fcimb.2018.00330] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 08/28/2018] [Indexed: 12/18/2022] Open
Abstract
Background: Intraocular tuberculosis (IOTB), an extrapulmonary manifestation of tuberculosis of the eye, has unique and varied clinical presentations with poorly understood pathogenesis. As it is a significant cause of inflammation and visual morbidity, particularly in TB endemic countries, it is essential to study the pathogenesis of IOTB. Clinical and histopathologic studies suggest the presence of Mycobacterium tuberculosis in retinal pigment epithelium (RPE) cells. Methods: A human retinal pigment epithelium (ARPE-19) cell line was infected with a virulent strain of M. tuberculosis (H37Rv). Electron microscopy and colony forming units (CFU) assay were performed to monitor the M. tuberculosis adherence, invasion, and intracellular replication, whereas confocal microscopy was done to study its intracellular fate in the RPE cells. To understand the pathogenesis, the transcriptional profile of M. tuberculosis in ARPE-19 cells was studied by whole genome microarray. Three upregulated M. tuberculosis transcripts were also examined in human IOTB vitreous samples. Results: Scanning electron micrographs of the infected ARPE-19 cells indicated adherence of bacilli, which were further observed to be internalized as monitored by transmission electron microscopy. The CFU assay showed that 22.7 and 8.4% of the initial inoculum of bacilli adhered and invaded the ARPE-19 cells, respectively, with an increase in fold CFU from 1 dpi (0.84) to 5dpi (6.58). The intracellular bacilli were co-localized with lysosomal-associated membrane protein-1 (LAMP-1) and LAMP-2 in ARPE-19 cells. The transcriptome study of intracellular bacilli showed that most of the upregulated transcripts correspond to the genes encoding the proteins involved in the processes such as adherence (e.g., Rv1759c and Rv1026), invasion (e.g., Rv1971 and Rv0169), virulence (e.g., Rv2844 and Rv0775), and intracellular survival (e.g., Rv1884c and Rv2450c) as well as regulators of various metabolic pathways. Two of the upregulated transcripts (Rv1971, Rv1230c) were also present in the vitreous samples of the IOTB patients. Conclusions:M. tuberculosis is phagocytosed by RPE cells and utilizes these cells for intracellular multiplication with the involvement of late endosomal/lysosomal compartments and alters its transcriptional profile plausibly for its intracellular adaptation and survival. The findings of the present study could be important to understanding the molecular pathogenesis of IOTB with a potential role in the development of diagnostics and therapeutics for IOTB.
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Affiliation(s)
- Sudhanshu Abhishek
- Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Uma Nahar Saikia
- Department of Histopathology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Amod Gupta
- Department of Ophthalmology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Reema Bansal
- Department of Ophthalmology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Vishali Gupta
- Department of Ophthalmology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Nirbhai Singh
- Department of Ophthalmology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Suman Laal
- Department of Pathology, New York University Langone Medical Center, New York, NY, United States
- Veterans Affairs New York Harbor Healthcare System, New York, NY, United States
| | - Indu Verma
- Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh, India
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19
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Yano H, Iwamoto T, Nishiuchi Y, Nakajima C, Starkova DA, Mokrousov I, Narvskaya O, Yoshida S, Arikawa K, Nakanishi N, Osaki K, Nakagawa I, Ato M, Suzuki Y, Maruyama F. Population Structure and Local Adaptation of MAC Lung Disease Agent Mycobacterium avium subsp. hominissuis. Genome Biol Evol 2018; 9:2403-2417. [PMID: 28957464 PMCID: PMC5622343 DOI: 10.1093/gbe/evx183] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/08/2017] [Indexed: 12/11/2022] Open
Abstract
Mycobacterium avium subsp. hominissuis (MAH) is one of the most common nontuberculous mycobacterial species responsible for chronic lung disease in humans. Despite increasing worldwide incidence, little is known about the genetic mechanisms behind the population evolution of MAH. To elucidate the local adaptation mechanisms of MAH, we assessed genetic population structure, the mutual homologous recombination, and gene content for 36 global MAH isolates, including 12 Japanese isolates sequenced in the present study. We identified five major MAH lineages and found that extensive mutual homologous recombination occurs among them. Two lineages (MahEastAsia1 and MahEastAsia2) were predominant in the Japanese isolates. We identified alleles unique to these two East Asian lineages in the loci responsible for trehalose biosynthesis (treS and mak) and in one mammalian cell entry operon, which presumably originated from as yet undiscovered mycobacterial lineages. Several genes and alleles unique to East Asian strains were located in the fragments introduced via recombination between East Asian lineages, suggesting implication of recombination in local adaptation. These patterns of MAH genomes are consistent with the signature of distribution conjugative transfer, a mode of sexual reproduction reported for other mycobacterial species.
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Affiliation(s)
- Hirokazu Yano
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan.,Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Tomotada Iwamoto
- Department of Infectious Diseases, Kobe Institute of Health, Kobe, Japan
| | - Yukiko Nishiuchi
- Toneyama Institute for Tuberculosis Research, Osaka City University Medical School, Osaka, Japan
| | - Chie Nakajima
- Division of Bioresources, Hokkaido University Research Center for Zoonosis Control, Sapporo, Japan.,The Global Station for Zoonosis Control, Hokkaido University Global Institution for Collaborative Research and Education, Sapporo, Japan
| | | | - Igor Mokrousov
- St. Petersburg Pasteur Institute, St. Petersburg, Russia
| | - Olga Narvskaya
- St. Petersburg Pasteur Institute, St. Petersburg, Russia
| | - Shiomi Yoshida
- Clinical Research Center, National Hospital Organization, Kinki-Chuo Chest Medical Center, Osaka, Japan
| | - Kentaro Arikawa
- Department of Infectious Diseases, Kobe Institute of Health, Kobe, Japan
| | - Noriko Nakanishi
- Department of Infectious Diseases, Kobe Institute of Health, Kobe, Japan
| | - Ken Osaki
- TOMY Digital Biology Co. Ltd, Taito-Ku, Tokyo, Japan
| | - Ichiro Nakagawa
- Department of Microbiology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Manabu Ato
- Department of Immunology, National Institute of Infectious Diseases, Shinjuku-Ku, Tokyo, Japan
| | - Yasuhiko Suzuki
- Division of Bioresources, Hokkaido University Research Center for Zoonosis Control, Sapporo, Japan.,The Global Station for Zoonosis Control, Hokkaido University Global Institution for Collaborative Research and Education, Sapporo, Japan
| | - Fumito Maruyama
- Department of Microbiology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
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20
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Khan S, Khan FI, Mohammad T, Khan P, Hasan GM, Lobb KA, Islam A, Ahmad F, Imtaiyaz Hassan M. Exploring molecular insights into the interaction mechanism of cholesterol derivatives with the Mce4A: A combined spectroscopic and molecular dynamic simulation studies. Int J Biol Macromol 2018; 111:548-560. [DOI: 10.1016/j.ijbiomac.2017.12.160] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 11/16/2017] [Accepted: 12/30/2017] [Indexed: 01/08/2023]
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21
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Indriarini D, Rukmana A, Yasmon A. CLONING AND EXPRESSION OF MCE1A GENE FROM MYCOBACTERIUM TUBERCULOSIS BEIJING AND H37RV STRAIN FOR VACCINE CANDIDATE DEVELOPMENT. Afr J Infect Dis 2018; 12:127-132. [PMID: 29619443 PMCID: PMC5876784 DOI: 10.2101/ajid.12v1s.19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 10/27/2017] [Accepted: 10/30/2017] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Tuberculosis remains the leading cause of death in the world, especially wherever poverty, malnutrition and poor housing prevail. Mycobacterium tuberculosis Beijing strain is the most common strain that causes tuberculosis in Indonesia. The wide spread of tuberculosis has been further aggravated by HIV-AIDS and drug resistance. Unfortunately, Bacille Calmette-Guerin (BCG) as the current vaccine has different protection function and efficacy. According to function analysis, mce1A gene was predicted to have a role in host invasion and survival of Mycobacterium tuberculosis in human macrophages. MATERIALS AND METHODS We performed cloning and protein expression of Mce1A gene of Mycobacterium tuberculosis Beijing strain as local isolate and standard strain H37Rv as a comparison on the expression system Escherichia coli BL21(DE3). Mce1A gene from the strains were amplified by PCR and inserted into the vector pET28a. Each resulting recombinant plasmid was subsequently transformed into E. coli BL21(DE3) and Mce1A protein was expressed with IPTG induction. RESULTS E. coli BL21(DE3) was succesfully transformed with a recombinant plasmid that contains the Mce1A gene insert with correct orientation and reading frame. There was no mutation found in the amino acids sequence for B and T cell epitope. Mce1A expression in E. coli BL21(DE3) showed a protein band that was higher than expected. The protein was confirmed with Western blotting using anti-His detector. CONCLUSION We assumed that Mce1A recombinant protein that has been expressed in E. coli BL21(DE3) is in their dimeric form or alternatively formed aggregates of different sizes.
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Affiliation(s)
- Desi Indriarini
- Department of Microbiology, Faculty of Medicine, University of Nusa Cendana, Kupang, Indonesia
| | - Andriansjah Rukmana
- Department of Microbiology, Faculty of Medicine, University of Indonesia, Jakarta, Indonesia
| | - Andi Yasmon
- Department of Microbiology, Faculty of Medicine, University of Indonesia, Jakarta, Indonesia
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22
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Singh P, Sinha R, Tyagi G, Sharma NK, Saini NK, Chandolia A, Prasad AK, Varma-Basil M, Bose M. PDIM and SL1 accumulation in Mycobacterium tuberculosis is associated with mce4A expression. Gene 2017; 642:178-187. [PMID: 28988960 DOI: 10.1016/j.gene.2017.09.062] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2017] [Revised: 08/30/2017] [Accepted: 09/26/2017] [Indexed: 02/05/2023]
Abstract
Lipid metabolism forms the heart and soul of Mycobacterium tuberculosis life cycle. Starting from macrophage invasion at cholesterol rich micro-domains to a sustainable survival for infection by utilizing cholesterol, Mycobacterium displays the nexus of metabolic pathways around host derived lipids. mce4 operon acts as cholesterol import system in M. tuberculosis and here we demonstrate role of mce4A gene of this operon in cholesterol catabolism. Here M. tuberculosis H37Rv overexpressing Rv3499c (mce4A) recombinant was used as a model to decipher the metabolic flux during intake and utilization of host lipids by mycobacteria. We analysed the impact of mce4A expression on carbon shift initiated during cholesterol utilization necessary for long term survival of mycobacterium. Through transcriptional analysis, upregulation in methylcitrate cycle (MCC) and methylmalonyl pathway (MMP) genes was observed in Rv3499c overexpressing recombinants of M. tuberculosis H37Rv. Up-regulation of methylmalonyl pathway associated enzyme encoding genes increased accumulation of virulence associated mycobacterial lipids phthiocerol dimycocerates (PDIM) and sulfolipid (SL1). We demonstrate that MCC and MMP associated enzyme encoding genes are upregulated upon mce4A overexpression and lead to enhanced accumulation of PDIM and SL1 which are responsible for pathogenicity of M. tuberculosis.
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Affiliation(s)
- Pooja Singh
- Department of Microbiology, V. P. Chest Institute, University of Delhi, Chatra Marg, Delhi, India; Public Health research Institute, New Jersey Medical School - Rutgers, The State University of New Jersey, Newark, NJ, USA
| | - Rajesh Sinha
- Department of Microbiology, V. P. Chest Institute, University of Delhi, Chatra Marg, Delhi, India; Department of Biochemistry, V. P. Chest Institute, University of Delhi, Chatra Marg, Delhi, India
| | - Gaurav Tyagi
- Department of Microbiology, V. P. Chest Institute, University of Delhi, Chatra Marg, Delhi, India
| | - Naresh Kumar Sharma
- Department of Microbiology, V. P. Chest Institute, University of Delhi, Chatra Marg, Delhi, India
| | - Neeraj K Saini
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Amita Chandolia
- Department of Microbiology, V. P. Chest Institute, University of Delhi, Chatra Marg, Delhi, India
| | - Ashok Kumar Prasad
- Department of Chemistry, Bioorganic Laboratory, University of Delhi, Delhi 110007, India
| | - Mandira Varma-Basil
- Department of Microbiology, V. P. Chest Institute, University of Delhi, Chatra Marg, Delhi, India
| | - Mridula Bose
- Department of Microbiology, V. P. Chest Institute, University of Delhi, Chatra Marg, Delhi, India.
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Abstract
The granuloma is the hallmark of tuberculosis and simultaneously signifies acquisition of an infection and induction of a host immune response. But who benefits more from the development of the granuloma, the host or the pathogen? Is microbe or man dictating disease course and progression? Mycobacterial diseases affect humans and animals alike, and the concepts presented in this review reflect host-pathogen interactions that influence not only mycobacterial granulomas in humans and animals but also other infectious granulomatous diseases that are encountered in veterinary medicine. Current dogma supports that an organized granuloma is a mark of an adequate and “restrictive” host immune response. However, the formation of a granuloma also provides a niche for the maturation, growth, and persistence of numerous infectious agents, and these pathogens devote some portion of their genetic machinery to ensuring these structures’ form. An understanding of pathogens’ contributions to granuloma formation can aid the development of host-directed therapies and other antimicrobial and antiparasitic therapies that can tip this balance in favor of a restrictive host response and elimination—not just containment—of the infectious organism. This review discusses animal models that have aided our understanding of pathogens’ contribution to the host response and how mycobacterial virulence genes direct host pathology in ways that may aid disease transmission and/or persistence in the form of latent infection.
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Affiliation(s)
- Amanda J. Martinot
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
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Ji X, Tan X, Hou X, Si C, Xu S, Tang L, Yuan X, Li Z. Cloning, Expression, Invasion, and Immunological Reactivity of a Mammalian Cell Entry Protein Encoded by the mce1 Operon of Nocardia farcinica. Front Microbiol 2017; 8:281. [PMID: 28275374 PMCID: PMC5319979 DOI: 10.3389/fmicb.2017.00281] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 02/09/2017] [Indexed: 11/13/2022] Open
Abstract
Bacterial mammalian cell entry (Mce) proteins have been implicated in pathogen invasion of mammalian host cells. The aim of this study was to examine the invasion-conferring ability of mce1E operon-encoded proteins, in vivo expression of Mce1E in cells from infected mice and rabbits, and Mce1E immunogenicity. Nocardia farcinica mce1E was cloned into pet30a(+) vectors, expressed in Escherichia coli, and purified. Invasion assays, transmission electron microscopy (TEM), immunoblots, and enzyme-linked immunosorbent assay (ELISA) detection of cytokines were conducted. TEM confirmed the invasion of HeLa cells by Mce1E-coated beads. The antigenicity of E. coli-expressed recombinant Mce1E was confirmed in immunoblots with sera from N. farcinica-infected mouse and rabbit sera. Co-incubation of Mce1E with splenocytes of N. farcinica-infected mice demonstrated upregulation of interferon (IFN-γ), but not interleukin (IL)-4 or IL-10, in the cultural supernatant. These findings demonstrate that Mce1E may facilitate N. farcinica interactions with and invasion of mammalian cells. Notably, Mce1E are expressed and elicited antibody responses in mice and rabbits during infection. Besides, it may play a role in cell-mediated immune reactions and cause host inflammation responses to N. farcinica infection.
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Affiliation(s)
- Xingzhao Ji
- State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention Beijing, China
| | - Xiaoluo Tan
- Office of Emergency Response, Chenzhou Center for Disease Control and PreventionChenzhou, China; School of Public Health, University of South ChinaHengyang, China
| | - Xuexin Hou
- State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention Beijing, China
| | - Chenchen Si
- State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention Beijing, China
| | - Shuai Xu
- State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention Beijing, China
| | - Lu Tang
- State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention Beijing, China
| | - Xiuqin Yuan
- School of Public Health, University of South China Hengyang, China
| | - Zhenjun Li
- State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention Beijing, China
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Sengupta S, Naz S, Das I, Ahad A, Padhi A, Naik SK, Ganguli G, Pattanaik KP, Raghav SK, Nandicoori VK, Sonawane A. Mycobacterium tuberculosis EsxL inhibits MHC-II expression by promoting hypermethylation in class-II transactivator loci in macrophages. J Biol Chem 2017; 292:6855-6868. [PMID: 28209712 DOI: 10.1074/jbc.m117.775205] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 02/13/2017] [Indexed: 12/13/2022] Open
Abstract
Mycobacterium tuberculosis is known to modulate the host immune responses to facilitate its persistence inside the host cells. One of the key mechanisms includes repression of class-II transactivator (CIITA) and MHC-II expression in infected macrophages. However, the precise mechanism of CIITA and MHC-II down-regulation is not well studied. M. tuberculosis 6-kDa early secretory antigenic target (ESAT-6) is a known potent virulence and antigenic determinant. The M. tuberculosis genome encodes 23 such ESAT-6 family proteins. We herein report that M. tuberculosis and M. bovis bacillus Calmette-Guérin infection down-regulated the expression of CIITA/MHC-II by inducing hypermethylation in histone H3 lysine 9 (H3K9me2/3). Further, we showed that M. tuberculosis ESAT-6 family protein EsxL, encoded by Rv1198, is responsible for the down-regulation of CIITA/MHC-II by inducing H3K9me2/3. We further report that M. tuberculosis esxL induced the expression of nitric-oxide synthase, NO production, and p38 MAPK pathway, which in turn was responsible for the increased H3K9me2/3 in CIITA via up-regulation of euchromatic histone-lysine N-methyltransferase 2 (G9a). In contrast, inhibition of nitric-oxide synthase, p38 MAPK, and G9a abrogated H3K9me2/3, resulting in increased CIITA expression. A chromatin immunoprecipitation assay confirmed that hypermethylation at the promoter IV region of CIITA is mainly responsible for CIITA down-regulation and subsequent antigen presentation. We found that co-culture of macrophages infected with esxL-expressing M. smegmatis and mouse splenocytes led to down-regulation of IL-2, a key cytokine involved in T-cell proliferation. In summary, we demonstrate that M. tuberculosis EsxL inhibits antigen presentation by enhancing H3K9me2/3 at the CIITA promoter, thereby repressing its expression through NO and p38 MAPK activation.
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Affiliation(s)
- Srabasti Sengupta
- From the School of Biotechnology, KIIT University, Bhubaneswar, Orissa 751024, India
| | - Saba Naz
- the National Institute of Immunology, New Delhi, Delhi 110067, India, and
| | - Ishani Das
- From the School of Biotechnology, KIIT University, Bhubaneswar, Orissa 751024, India
| | - Abdul Ahad
- the Institute of Life Science, Nalco Square, Bhubaneswar, Orissa 751023, India
| | - Avinash Padhi
- From the School of Biotechnology, KIIT University, Bhubaneswar, Orissa 751024, India
| | - Sumanta Kumar Naik
- From the School of Biotechnology, KIIT University, Bhubaneswar, Orissa 751024, India
| | - Geetanjali Ganguli
- From the School of Biotechnology, KIIT University, Bhubaneswar, Orissa 751024, India
| | - Kali Prasad Pattanaik
- From the School of Biotechnology, KIIT University, Bhubaneswar, Orissa 751024, India
| | - Sunil Kumar Raghav
- the Institute of Life Science, Nalco Square, Bhubaneswar, Orissa 751023, India
| | | | - Avinash Sonawane
- From the School of Biotechnology, KIIT University, Bhubaneswar, Orissa 751024, India,
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Faletrov Y, Brzostek A, Plocinska R, Dziadek J, Rudaya E, Edimecheva I, Shkumatov V. Uptake and metabolism of fluorescent steroids by mycobacterial cells. Steroids 2017; 117:29-37. [PMID: 27718364 DOI: 10.1016/j.steroids.2016.10.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2016] [Revised: 09/29/2016] [Accepted: 10/01/2016] [Indexed: 11/26/2022]
Abstract
Fluorescent steroids BODIPY-cholesterol (BPCh) and 7-nitrobenzoxadiazole-4-amino-(NBD)-labeled 22-NBD-chelesterol (22NC) as well as synthesized 20-(NBD)-pregn-5-en-3β-ol (20NP) were found to undergo bioconversions by Mycobacterium tuberculosis H37Rv and M. smegmatis mc2 155. The major fluorescent products were determined to be 4-en-3-one derivatives of the compounds. Degradation of NBD fluorophore was also detected in the cases of 22NC and 20NP, but neither NBD degradation nor steroidal part modification were observed for the synthesized 3-(NBD)-cholestane. Mycobacterial 3β-hydroxysteroid dehydrogenases were concluded to be responsible for the formation of the 4-en-3-one derivatives. All the compounds tested were found to cause staining both membrane lipids and cytosolic lipid droplets when incubated with mycobacteria in different manner, demonstrating ability of the steroids to reside in the compartments. The findings reveal a potential of the compounds for monitoring of steroid interactions with mycobacteria and provide information for design of new probes for this purpose.
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Affiliation(s)
- Yaroslav Faletrov
- Research Institute for Physical Chemical Problems, Belarusian State University, Minsk, Belarus; Faculty of Chemistry, Belarusian State University, Minsk, Belarus.
| | - Anna Brzostek
- Institute of Medical Biology, Polish Academy of Sciences, Lodz, Poland.
| | - Renata Plocinska
- Institute of Medical Biology, Polish Academy of Sciences, Lodz, Poland.
| | - Jarosław Dziadek
- Institute of Medical Biology, Polish Academy of Sciences, Lodz, Poland.
| | - Elena Rudaya
- Research Institute for Physical Chemical Problems, Belarusian State University, Minsk, Belarus; Faculty of Chemistry, Belarusian State University, Minsk, Belarus.
| | - Irina Edimecheva
- Faculty of Chemistry, Belarusian State University, Minsk, Belarus.
| | - Vladimir Shkumatov
- Research Institute for Physical Chemical Problems, Belarusian State University, Minsk, Belarus; Faculty of Chemistry, Belarusian State University, Minsk, Belarus.
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27
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Fozo EM, Rucks EA. The Making and Taking of Lipids: The Role of Bacterial Lipid Synthesis and the Harnessing of Host Lipids in Bacterial Pathogenesis. Adv Microb Physiol 2016; 69:51-155. [PMID: 27720012 DOI: 10.1016/bs.ampbs.2016.07.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
In order to survive environmental stressors, including those induced by growth in the human host, bacterial pathogens will adjust their membrane physiology accordingly. These physiological changes also include the use of host-derived lipids to alter their own membranes and feed central metabolic pathways. Within the host, the pathogen is exposed to many stressful stimuli. A resulting adaptation is for pathogens to scavenge the host environment for readily available lipid sources. The pathogen takes advantage of these host-derived lipids to increase or decrease the rigidity of their own membranes, to provide themselves with valuable precursors to feed central metabolic pathways, or to impact host signalling and processes. Within, we review the diverse mechanisms that both extracellular and intracellular pathogens employ to alter their own membranes as well as their use of host-derived lipids in membrane synthesis and modification, in order to increase survival and perpetuate disease within the human host. Furthermore, we discuss how pathogen employed mechanistic utilization of host-derived lipids allows for their persistence, survival and potentiation of disease. A more thorough understanding of all of these mechanisms will have direct consequences for the development of new therapeutics, and specifically, therapeutics that target pathogens, while preserving normal flora.
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Affiliation(s)
- E M Fozo
- University of Tennessee, Knoxville, TN, United States.
| | - E A Rucks
- Sanford School of Medicine, University of South Dakota, Vermillion, SD, United States.
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28
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Saini NK, Sinha R, Singh P, Sharma M, Pathak R, Rathor N, Varma-Basil M, Bose M. Mce4A protein of Mycobacterium tuberculosis induces pro inflammatory cytokine response leading to macrophage apoptosis in a TNF-α dependent manner. Microb Pathog 2016; 100:43-50. [PMID: 27592091 DOI: 10.1016/j.micpath.2016.08.038] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 08/25/2016] [Accepted: 08/30/2016] [Indexed: 11/19/2022]
Abstract
Mycobacterium tuberculosis subverts the host immune response through numerous immune-evasion strategies. Apoptosis has been identified as one such mechanism and has been well studied in M. tuberculosis infection. Here, we demonstrate that the Mce4A protein of mce4 operon is involved in the induction of host cell apoptosis. Earlier we have shown that the Mce4A was required for the invasion and survival of M. tuberculosis. In this report we present evidence to establish a role for Mce4A in the modulation of THP-1 cell survival. Recombinant Mce4A was expressed and purified from Escherichia coli as inclusion bodies and then refolded. Viability of THP-1 cells decreased in a dose-dependent manner when treated with Mce4A. The secretion of pro-inflammatory cytokines like tumor necrosis factor (TNF-α) or interferon gamma (IFN-γ), and enhanced nitric oxide release was observed when the THP-1 cells, were treated with Mce4A protein. The Mce4A induced apoptosis of the THP-1 cells was TNF-α dependent since blocking with anti TNF-α antibody abrogated this phenomenon. Collectively, these data suggest that Mce4A can induce the THP-1 cells to undergo apoptosis which primarily follows a TNF- α dependent pathway.
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Affiliation(s)
- Neeraj Kumar Saini
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, 110007, India; Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Rajesh Sinha
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, 110007, India; Department of Biochemistry, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, 110007, India
| | - Pooja Singh
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, 110007, India
| | - Monika Sharma
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, 110007, India; Department of Zoology, Miranda House, University of Delhi, Delhi, 110007, India
| | - Rakesh Pathak
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, 110007, India
| | - Nisha Rathor
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, 110007, India
| | - Mandira Varma-Basil
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, 110007, India
| | - Mridula Bose
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, 110007, India.
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29
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Rathor N, Garima K, Sharma NK, Narang A, Varma-Basil M, Bose M. Expression profile of mce4 operon of Mycobacterium tuberculosis following environmental stress. Int J Mycobacteriol 2016; 5:328-332. [PMID: 27847019 DOI: 10.1016/j.ijmyco.2016.08.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 08/06/2016] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND The mce4 operon is one of the four mce operons with eight genes (yrbE4A, yrbE4B, mce4A, mce4B, mce4C, mce4D, mce4E and mce4F) of Mycobacterium tuberculosis. It expresses in the later phase of infection and imports cholesterol for long term survival of the bacilli. To cause latent infection, M. tuberculosis undergoes metabolic reprogramming of its genes to survive in the hostile environment like low availability of oxygen and nutrition depletion inside the host. OBJECTIVE To analyze real time expression profile of mce4 operon under various stress conditions. METHODS M. tuberculosis H37Rv was exposed to surface stress (0.1% SDS for 30min and 90min in late log and stationary phase of culture), hypoxia (5, 10, 15 and 20days) and grown in the presence of either glycerol or cholesterol as sole source of carbon. The expression profile of genes of mce4 operon was analyzed by real time PCR. RESULTS Surface stress induced expression of mce4C and yrbE4B in late log phase on 30min and 90min exposure respectively. The SDS exposure for 30min induced mce4C, mce4D and mce4F in stationary phase. All eight genes were induced significantly on 10th and 15th days of hypoxia and in the presence of cholesterol. CONCLUSION Hypoxia and cholesterol are potent factors for the expression of mce4 operon of M. tuberculosis.
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Affiliation(s)
- Nisha Rathor
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
| | - Kushal Garima
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
| | - Naresh Kumar Sharma
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
| | - Anshika Narang
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
| | - Mandira Varma-Basil
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
| | - Mridula Bose
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India.
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30
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Khan S, Islam A, Hassan MI, Ahmad F. Purification and structural characterization of Mce4A from Mycobacterium tuberculosis. Int J Biol Macromol 2016; 93:235-241. [PMID: 27355757 DOI: 10.1016/j.ijbiomac.2016.06.059] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 06/17/2016] [Accepted: 06/19/2016] [Indexed: 01/08/2023]
Abstract
The mce4A gene of Mycobacterium tuberculosis encodes a 400 amino acid residues protein of 43kDa, which is a mammalian cell entry protein (Mce4A) and plays important role in host cell invasion. Mce4A helps in long-term survival of M. tuberculosis by cholesterol utilization. Host cholesterol utilization mechanism by Mce4A is not clearly understood. In order to investigate the role of Mce4A in M. tuberculosis pathogenesis, we purified the recombinant protein by affinity chromatography, analyzed by SDS-PAGE and confirmed by western blot. We performed structural studies of Mce4A as function of pH and salt concentration by using different spectroscopic techniques. This protein was found to be stable over the wide range of pH 5.5≤pH≤11.5. An addition of sodium chloride up to the concentration of 150mM, shows no significant change in the secondary structure content of the protein. To confirm its activity, we performed isothermal titration calorimetry measurements of Mce4A in the presence of cholesterol. This is the first report of binding of cholesterol to Mce4A in vitro. Binding of cholesterol to Mce4A is sequential four-step and entropy driven process. The structural studies of this protein will help to understand the mechanism of pathogenesis of M. tuberculosis.
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Affiliation(s)
- Shagufta Khan
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi 110025, India
| | - Asimul Islam
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi 110025, India.
| | - Md Imtaiyaz Hassan
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi 110025, India
| | - Faizan Ahmad
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi 110025, India
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31
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Mohanty S, Dal Molin M, Ganguli G, Padhi A, Jena P, Selchow P, Sengupta S, Meuli M, Sander P, Sonawane A. Mycobacterium tuberculosis EsxO (Rv2346c) promotes bacillary survival by inducing oxidative stress mediated genomic instability in macrophages. Tuberculosis (Edinb) 2015; 96:44-57. [PMID: 26786654 DOI: 10.1016/j.tube.2015.11.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 11/09/2015] [Accepted: 11/17/2015] [Indexed: 12/19/2022]
Abstract
Mycobacterium tuberculosis (Mtb) survives inside the macrophages by modulating the host immune responses in its favor. The 6-kDa early secretory antigenic target (ESAT-6; esxA) of Mtb is known as a potent virulence and T-cell antigenic determinant. At least 23 such ESAT-6 family proteins are encoded in the genome of Mtb; however, the function of many of them is still unknown. We herein report that ectopic expression of Mtb Rv2346c (esxO), a member of ESAT-6 family proteins, in non-pathogenic Mycobacterium smegmatis strain (MsmRv2346c) aids host cell invasion and intracellular bacillary persistence. Further mechanistic studies revealed that MsmRv2346c infection abated macrophage immunity by inducing host cell death and genomic instability as evident from the appearance of several DNA damage markers. We further report that the induction of genomic instability in infected cells was due to increase in the hosts oxidative stress responses. MsmRv2346c infection was also found to induce autophagy and modulate the immune function of macrophages. In contrast, blockade of Rv2346c induced oxidative stress by treatment with ROS inhibitor N-acetyl-L-cysteine prevented the host cell death, autophagy induction and genomic instability in infected macrophages. Conversely, MtbΔRv2346c mutant did not show any difference in intracellular survival and oxidative stress responses. We envision that Mtb ESAT-6 family protein Rv2346c dampens antibacterial effector functions namely by inducing oxidative stress mediated genomic instability in infected macrophages, while loss of Rv2346c gene function may be compensated by other redundant ESAT-6 family proteins. Thus EsxO plays an important role in mycobacterial pathogenesis in the context of innate immunity.
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Affiliation(s)
- Soumitra Mohanty
- School of Biotechnology, KIIT University, Bhubaneswar, Odisha, India
| | - Michael Dal Molin
- Institute of Medical Microbiology, University of Zurich, Gloriastrasse 32, CH 8006 Zurich, Switzerland
| | | | - Avinash Padhi
- School of Biotechnology, KIIT University, Bhubaneswar, Odisha, India
| | - Prajna Jena
- School of Biotechnology, KIIT University, Bhubaneswar, Odisha, India
| | - Petra Selchow
- Institute of Medical Microbiology, University of Zurich, Gloriastrasse 32, CH 8006 Zurich, Switzerland
| | - Srabasti Sengupta
- School of Biotechnology, KIIT University, Bhubaneswar, Odisha, India
| | - Michael Meuli
- Institute of Medical Microbiology, University of Zurich, Gloriastrasse 32, CH 8006 Zurich, Switzerland
| | - Peter Sander
- Institute of Medical Microbiology, University of Zurich, Gloriastrasse 32, CH 8006 Zurich, Switzerland; National Reference Laboratory for Mycobacteria, Gloriastrasse 30, CH 8006 Zurich, Switzerland
| | - Avinash Sonawane
- School of Biotechnology, KIIT University, Bhubaneswar, Odisha, India.
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32
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George R, Cavalcante R, Jr CC, Marques E, Waugh JB, Unlap MT. Use of siRNA molecular beacons to detect and attenuate mycobacterial infection in macrophages. World J Exp Med 2015; 5:164-181. [PMID: 26309818 PMCID: PMC4543811 DOI: 10.5493/wjem.v5.i3.164] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Revised: 05/05/2015] [Accepted: 06/11/2015] [Indexed: 02/06/2023] Open
Abstract
Tuberculosis is one of the leading infectious diseases plaguing mankind and is mediated by the facultative pathogen, Mycobacterium tuberculosis (MTB). Once the pathogen enters the body, it subverts the host immune defenses and thrives for extended periods of time within the host macrophages in the lung granulomas, a condition called latent tuberculosis (LTB). Persons with LTB are prone to reactivation of the disease when the body’s immunity is compromised. Currently there are no reliable and effective diagnosis and treatment options for LTB, which necessitates new research in this area. The mycobacterial proteins and genes mediating the adaptive responses inside the macrophage is largely yet to be determined. Recently, it has been shown that the mce operon genes are critical for host cell invasion by the mycobacterium and for establishing a persistent infection in both in vitro and in mouse models of tuberculosis. The YrbE and Mce proteins which are encoded by the MTB mce operons display high degrees of homology to the permeases and the surface binding protein of the ABC transports, respectively. Similarities in structure and cell surface location impute a role in cell invasion at cholesterol rich regions and immunomodulation. The mce4 operon is also thought to encode a cholesterol transport system that enables the mycobacterium to derive both energy and carbon from the host membrane lipids and possibly generating virulence mediating metabolites, thus enabling the bacteria in its long term survival within the granuloma. Various deletion mutation studies involving individual or whole mce operon genes have shown to be conferring varying degrees of attenuation of infectivity or at times hypervirulence to the host MTB, with the deletion of mce4A operon gene conferring the greatest degree of attenuation of virulence. Antisense technology using synthetic siRNAs has been used in knocking down genes in bacteria and over the years this has evolved into a powerful tool for elucidating the roles of various genes mediating infectivity and survival in mycobacteria. Molecular beacons are a newer class of antisense RNA tagged with a fluorophore/quencher pair and their use for in vivo detection and knockdown of mRNA is rapidly gaining popularity.
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Gautam US, Mehra S, Kaushal D. In-Vivo Gene Signatures of Mycobacterium tuberculosis in C3HeB/FeJ Mice. PLoS One 2015; 10:e0135208. [PMID: 26270051 PMCID: PMC4535907 DOI: 10.1371/journal.pone.0135208] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Accepted: 07/19/2015] [Indexed: 11/28/2022] Open
Abstract
Despite considerable progress in understanding the pathogenesis of Mycobacterium tuberculosis (Mtb), development of new therapeutics and vaccines against it has proven difficult. This is at least in part due to the use of less than optimal models of in-vivo Mtb infection, which has precluded a study of the physiology of the pathogen in niches where it actually persists. C3HeB/FeJ (Kramnik) mice develop human-like lesions when experimentally infected with Mtb and thus make available, a faithful and highly tractable system to study the physiology of the pathogen in-vivo. We compared the transcriptomics of Mtb and various mutants in the DosR (DevR) regulon derived from Kramnik mouse granulomas to those cultured in-vitro. We recently showed that mutant ΔdosS is attenuated in C3HeB/FeJ mice. Aerosol exposure of mice with the mutant mycobacteria resulted in a substantially different and a relatively weaker transcriptional response (< = 20 genes were induced) for the functional category ‘Information Pathways’ in Mtb:ΔdosR; ‘Lipid Metabolism’ in Mtb:ΔdosT; ‘Virulence, Detoxification, Adaptation’ in both Mtb:ΔdosR and Mtb:ΔdosT; and ‘PE/PPE’ family in all mutant strains compare to wild-type Mtb H37Rv, suggesting that the inability to induce DosR functions to different levels can modulate the interaction of the pathogen with the host. The Mtb genes expressed during growth in C3HeB/FeJ mice appear to reflect adaptation to differential nutrient utilization for survival in mouse lungs. The genes such as glnB, Rv0744c, Rv3281, sdhD/B, mce4A, dctA etc. downregulated in mutant ΔdosS indicate their requirement for bacterial growth and flow of carbon/energy source from host cells. We conclude that genes expressed in Mtb during in-vivo chronic phase of infection in Kramnik mice mainly contribute to growth, cell wall processes, lipid metabolism, and virulence.
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Affiliation(s)
- Uma Shankar Gautam
- Tulane National Primate Research Center, Covington, Louisiana, United States of America
- * E-mail: (DK); (USG)
| | - Smriti Mehra
- Tulane National Primate Research Center, Covington, Louisiana, United States of America
- Louisiana State University School of Veterinary Medicine Department of Pathobiological Sciences, Baton Rouge, Louisiana, United States of America
| | - Deepak Kaushal
- Tulane National Primate Research Center, Covington, Louisiana, United States of America
- Microbiology and Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
- * E-mail: (DK); (USG)
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Viswanathan G, Joshi SV, Sridhar A, Dutta S, Raghunand TR. Identifying novel mycobacterial stress associated genes using a random mutagenesis screen in Mycobacterium smegmatis. Gene 2015. [PMID: 26211627 DOI: 10.1016/j.gene.2015.07.063] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Cell envelope associated components of Mycobacterium tuberculosis (M.tb) have been implicated in stress response, immune modulation and in vivo survival of the pathogen. Although many such factors have been identified, there is a large disparity between the number of genes predicted to be involved in functions linked to the envelope and those described in the literature. To identify and characterise novel stress related factors associated with the mycobacterial cell envelope, we isolated colony morphotype mutants of Mycobacterium smegmatis (M. smegmatis), based on the hypothesis that mutants with unusual colony morphology may have defects in the biosynthesis of cell envelope components. On testing their susceptibility to stress conditions relevant to M.tb physiology, multiple mutants were found to be sensitive to Isoniazid, Diamide and H2O2, indicative of altered permeability due to changes in cell envelope composition. Two mutants showed defects in biofilm formation implying possible roles for the target genes in antibiotic tolerance and/or virulence. These assays identified novel stress associated roles for several mycobacterial genes including sahH, tatB and aceE. Complementation analysis of selected mutants with the M. smegmatis genes and their M.tb homologues showed phenotypic restoration, validating their link to the observed phenotypes. A mutant carrying an insertion in fhaA encoding a forkhead associated domain containing protein, showed reduced survival in THP-1 macrophages, providing in vivo validation to this screen. Taken together, these results suggest that the M.tb homologues of a majority of the identified genes may play significant roles in the pathogenesis of tuberculosis.
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Affiliation(s)
| | - Shrilaxmi V Joshi
- CSIR - Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, India
| | - Aditi Sridhar
- CSIR - Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, India
| | - Sayantanee Dutta
- CSIR - Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, India
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35
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He L, Zhou X, Yin X, Tian L, Yang L, Fan K, Zhao D. Comparative study of the growth and survival of recombinant Mycobacterium smegmatis expressing Mce4A and Mce4E from Mycobacterium bovis. DNA Cell Biol 2014; 34:125-32. [PMID: 25536284 DOI: 10.1089/dna.2014.2487] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Cholesterol is important for the growth and persistence of Mycobacterium tuberculosis in macrophages. The mce4 locus, which is conserved in both M. tuberculosis and Mycobacterium bovis, is thought to be responsible for cholesterol transport into the bacteria. However, the exact roles of specific genes within the sophisticated mce4 system remain poorly understood. In this study, Mce4A and Mce4E of M. bovis, two proteins that are encoded by the mce4 locus, were expressed in Mycobacterium smegmatis. The recombinant strain expressing the Mce4E protein (M. smeg::E) performed better than that expressing the Mce4A protein (M. smeg::A) in a minimal medium with and without glycerol or cholesterol, which may be the reason why M. smeg::E showed better survival in ANA-1 macrophages than did M. smeg::A. Cytokine expression profiles were similar in macrophages infected with either recombinant strain. We also investigated the role of CD36 in recognizing Mce4A and Mce4E proteins. However, CD36 did not appear to be specific for these proteins and showed little impact on the ultimate clearance of the recombinant strains. Reduced interleukin-1β, inducible nitric oxide synthase, and tumor necrosis factor-alpha mRNA expression at 6 h postinfection in macrophages infected with M. smeg::E was observed using a CD36-specific monocular antibody to block the receptor, whereas no obvious changes in the expression of these cytokines were observed in cells infected with M. smeg::A with or without exposure to the CD36 antibody. Conclusively, the different performances of the recombinant strains suggest that the Mce4A and Mce4E proteins enhance mycobacterial adaptation to the harsh environment within macrophages after phagocytosis.
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Affiliation(s)
- Liu He
- 1 The State Key Lab of Agrobiotechnology, Key Lab of Animal Epidemiology and Zoonosis Ministry of Agriculture, National TSE Lab, College of Veterinary Medicine, China Agricultural University , Beijing, People's Republic of China
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36
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Jaglic Z, Desvaux M, Weiss A, Nesse LL, Meyer RL, Demnerova K, Schmidt H, Giaouris E, Sipailiene A, Teixeira P, Kačániová M, Riedel CU, Knøchel S. Surface adhesins and exopolymers of selected foodborne pathogens. MICROBIOLOGY-SGM 2014; 160:2561-2582. [PMID: 25217529 DOI: 10.1099/mic.0.075887-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The ability of bacteria to bind different compounds and to adhere to biotic and abiotic surfaces provides them with a range of advantages, such as colonization of various tissues, internalization, avoidance of an immune response, and survival and persistence in the environment. A variety of bacterial surface structures are involved in this process and these promote bacterial adhesion in a more or less specific manner. In this review, we will focus on those surface adhesins and exopolymers in selected foodborne pathogens that are involved mainly in primary adhesion. Their role in biofilm development will also be considered when appropriate. Both the clinical impact and the implications for food safety of such adhesion will be discussed.
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Affiliation(s)
- Zoran Jaglic
- Veterinary Research Institute, Brno, Czech Republic
| | - Mickaël Desvaux
- INRA, UR454 Microbiologie, F-63122 Saint-Genès Champanelle, France
| | - Agnes Weiss
- Department of Food Microbiology, Institute of Food Science and Biotechnology, University of Hohenheim, Garbenstrasse 28, 70599 Stuttgart, Germany
| | | | - Rikke L Meyer
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, DK-8000 Aarhus C, Denmark
| | - Katerina Demnerova
- Institute of Chemical Technology, Faculty of Food and Biochemical Technology, Department of Biochemistry and Microbiology, Technicka 5, Prague, 166 28, Czech Republic
| | - Herbert Schmidt
- Department of Food Microbiology, Institute of Food Science and Biotechnology, University of Hohenheim, Garbenstrasse 28, 70599 Stuttgart, Germany
| | - Efstathios Giaouris
- Department of Food Science and Nutrition, Faculty of the Environment, University of the Aegean, 81400 Myrina, Lemnos Island, Greece
| | | | - Pilar Teixeira
- CEB - Centre of Biological Engineering, University of Minho, Braga, Portugal
| | | | - Christian U Riedel
- Institute of Microbiology and Biotechnology, University of Ulm, Ulm, Germany
| | - Susanne Knøchel
- Department of Food Science, University of Copenhagen, Rolighedsvej 30, Frederiksberg C 1958, Denmark
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Pasricha R, Saini NK, Rathor N, Pathak R, Sinha R, Varma-Basil M, Mishra K, Brahmachari V, Bose M. The Mycobacterium tuberculosis recombinant LprN protein of mce4 operon induces Th-1 type response deleterious to protection in mice. Pathog Dis 2014; 72:188-96. [PMID: 24989028 DOI: 10.1111/2049-632x.12200] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2013] [Revised: 06/20/2014] [Accepted: 06/20/2014] [Indexed: 11/30/2022] Open
Abstract
Lipoproteins are known to be effective immunogens and affect both innate and adaptive immunity. The lprN gene of Mycobacterium tuberculosis has been predicted to encode for a putative lipoprotein in silico. Here, we studied its function as an immunogen by in vivo studies in mice. The recombinant LprN protein, expressed and purified in Escherichia coli, triggered a cell-mediated immune response in BALB/c mice. This was observed by significantly higher T-cell proliferation and increased production of TNF-α and IFN-γ cytokines. However, pre-exposure to LprN protein failed to provide protection in mice after challenge with a virulent strain of M. tuberculosis. Histological examination showed an increase in tissue destruction in experimental animals, indicating an immunogenic potential for LprN protein that enhanced the virulence of bacilli.
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Affiliation(s)
- Rashmi Pasricha
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
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38
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Chandolia A, Rathor N, Sharma M, Saini NK, Sinha R, Malhotra P, Brahmachari V, Bose M. Functional analysis of mce4A gene of Mycobacterium tuberculosis H37Rv using antisense approach. Microbiol Res 2014; 169:780-7. [PMID: 24556072 DOI: 10.1016/j.micres.2013.12.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Revised: 12/17/2013] [Accepted: 12/28/2013] [Indexed: 01/21/2023]
Abstract
Antisense strategy is an attractive substitute for knockout mutations created for gene silencing. mce genes have been shown to be involved in mycobacterial uptake and intracellular survival. Here we report reduced expression of mce4A and mce1A genes of Mycobacterium tuberculosis using antisense technology. For this, 1.1 kb region of mce4A and mce1A was cloned in reverse orientation in pSD5 shuttle vector, resulting into antisense constructs pSD5-4AS and pSD5-1AS, respectively. In M. tuberculosis H37Rv approximately 60% reduction in Mce4A and 66% reduction in expression of Mce1A protein were observed. We also observed significantly reduced intracellular survival ability of both antisense strains in comparison to M. tuberculosis containing pSD5 alone. RT-PCR analysis showed antisense did not alter the transcription of upstream and downstream of mceA genes of the respective operon. The colony morphology, in vitro growth characteristics and drug susceptibility profile of the antisense construct remained unchanged. These results demonstrate that antisense can be a promising approach to assign function of a gene in a multiunit operon and could be suitably applied as a strategy.
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Affiliation(s)
- Amita Chandolia
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi 110007, India.
| | - Nisha Rathor
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi 110007, India.
| | - Monika Sharma
- Department of Zoology, Miranda House, University of Delhi, Delhi 110007, India.
| | - Neeraj Kumar Saini
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi 110007, India.
| | - Rajesh Sinha
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi 110007, India.
| | - Pawan Malhotra
- International Center for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi 110067, India.
| | - Vani Brahmachari
- Dr. B.R. Ambedkar Center for Biomedical Research, University of Delhi, Delhi 110007, India.
| | - Mridula Bose
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi 110007, India.
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Rathor N, Chandolia A, Saini NK, Sinha R, Pathak R, Garima K, Singh S, Varma-Basil M, Bose M. An insight into the regulation of mce4 operon of Mycobacterium tuberculosis. Tuberculosis (Edinb) 2013; 93:389-97. [PMID: 23622789 DOI: 10.1016/j.tube.2013.03.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Revised: 02/19/2013] [Accepted: 03/30/2013] [Indexed: 01/21/2023]
Abstract
The mce4 operon is reported to be involved in cholesterol utilization and intracellular survival of Mycobacterium tuberculosis (M. tuberculosis). The regulatory mechanism of this important operon was unknown so far. Here we report detection of the promoter region and regulatory factors of the mce4 operon. The in silico analyzed putative promoter region was cloned in promoter selection vector and promoter strength was measured by O-Nitrophenyl-β-D-galactopyranosidase (ONPG) assay. The transcription start site was determined by 5' Rapid amplification of C terminal end (5'RACE). Surface stress, hypoxia and presence of cholesterol, were found to be stimulatory for mce4 operon promoter induction. Pull down assay coupled with 2D gel electrophoresis resolved many proteins; few prominent spots were processed for identification. MALDI TOF-TOF identified proteins of M. tuberculosis which supported the regulatory function of the identified promoter region and cholesterol utilization of mce4 operon. Since mce4 operon is involved in cholesterol utilization and intracellular survival of M. tuberculosis in the later phase of infection, identification of the promoter sequence as reported in the present communication may facilitate development of effective inhibitors to regulate expression of mce4 operon which may prove to be a good drug target to prevent latency in tuberculosis.
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Affiliation(s)
- Nisha Rathor
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi 110007, India.
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40
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Ocampo M, Patarroyo MA, Vanegas M, Alba MP, Patarroyo ME. Functional, biochemical and 3D studies ofMycobacterium tuberculosisprotein peptides for an effective anti-tuberculosis vaccine. Crit Rev Microbiol 2013; 40:117-45. [DOI: 10.3109/1040841x.2013.763221] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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41
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Krachler AM, Ham H, Orth K. Turnabout is fair play: use of the bacterial Multivalent Adhesion Molecule 7 as an antimicrobial agent. Virulence 2012; 3:68-71. [PMID: 22086133 DOI: 10.4161/viru.3.1.18172] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Pathogen attachment to host tissues is one of the initial and most crucial events during the establishment of bacterial infections and thus interference with this step could be an efficient strategy to fight bacterial colonization. Our recent work has identified one of the factors involved in initial binding of host cells by a wide range of Gram-negative pathogens, Multivalent Adhesion Molecule (MAM) 7. Interference with MAM7-mediated attachment, for example by pre-incubation of host cells with recombinant MAM7, significantly delays the onset of hallmarks of infection, such as pathogen-mediated cytotoxicity or the development of other adhesive structures such as actin pedestals. Thus, we are trying to develop tools based on MAM7 that can be used to prevent or diminish certain Gram-negative bacterial infections. Herein, we describe the use of bead-coupled MAM7 as an inhibitor of infection with the clinically relevant pathogen Pseudomonas aeruginosa.
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Affiliation(s)
- Anne Marie Krachler
- Department of Molecular Biology, UT Southwestern Medical Center, Dallas, TX, USA
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42
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Polyclonal antibody against conserved sequences of mce1A protein blocks MTB infection in macrophages. Appl Microbiol Biotechnol 2011; 93:2463-73. [PMID: 22159737 DOI: 10.1007/s00253-011-3754-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Revised: 11/03/2011] [Accepted: 11/21/2011] [Indexed: 10/14/2022]
Abstract
The pathogenesis of Mycobacterium tuberculosis is largely due to its ability to enter and survive within human macrophages. It is suggested that a specific protein namely mammalian cell entry protein is involved in the pathogenesis and the specific gene for this protein mce1A has been identified in several pathogenic organisms such as Rickettsia, Shigella, Escherichia coli, Helicobacter, Streptomyces, Klebsiella, Vibrio, Neisseria, Rhodococcus, Nocardioides, Saccharopolyspora erthyrae, and Pseudomonas. Analysis of mce1 operons in the above mentioned organisms through bioinformatics tools has revealed the presence of unique sequences (conserved regions) suggesting that these sequences may be involved in the process of infection. Presently, the mce1A full-length (1,365 bp) region from Mycobacterium bovis and its conserved regions (303 bp) were cloned in to an expression vector and the purified expressed proteins of molecular weight ~47 and ~11 kDa, respectively, were injected to rabbits to raise the polyclonal antibodies. The purified polyclonal antibodies were checked for their ability to inhibit the Mycobacterium infection in cultured human macrophages. In macrophage invasion assay, when antibody added at high concentration, decrease in viable counts was observed in all cell cultures within the first 5 days after infection, where the intracellular bacterial CFU obtained from the infected MTB increased by the 3rd day at low concentration of antibody. The macrophage invasion assay has indicated that the purified antibodies of mce1A conserved region can inhibit the infection of Mycobacterium.
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43
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Krachler AM, Orth K. Functional characterization of the interaction between bacterial adhesin multivalent adhesion molecule 7 (MAM7) protein and its host cell ligands. J Biol Chem 2011; 286:38939-47. [PMID: 21937438 DOI: 10.1074/jbc.m111.291377] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The ability of a pathogen to rapidly form a stable interaction with the host cell surface is key to its success. Bacterial pathogens use a repertoire of virulence factors, but their efficient use relies on close contact between the host and the pathogen. We have recently identified a constitutively expressed MAM7 (multivalent adhesion molecule 7), which is widely distributed in gram-negative pathogens and enables them to establish initial contact with the host cell. Here, we describe the dissection of the MAM7 interaction with the host cell surface into two distinct binding events, involving the host protein fibronectin and the membrane phospholipid phosphatidic acid. We analyzed which domains within MAM7 and fibronectin are necessary for complex formation. We further studied phosphatidic acid binding by MAM7 using site-directed mutagenesis and liposome association assays and demonstrated that a specific distribution of basic charge on MAM7 is required for high affinity binding. Finally, we showed that fibronectin and phosphatidic acid binding to MAM7 are not mutually exclusive and that the three molecules likely assemble into a tripartite complex on the host cell surface.
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Affiliation(s)
- Anne Marie Krachler
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
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44
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Pasricha R, Chandolia A, Ponnan P, Saini NK, Sharma S, Chopra M, Basil MV, Brahmachari V, Bose M. Single nucleotide polymorphism in the genes of mce1 and mce4 operons of Mycobacterium tuberculosis: analysis of clinical isolates and standard reference strains. BMC Microbiol 2011; 11:41. [PMID: 21345183 PMCID: PMC3050694 DOI: 10.1186/1471-2180-11-41] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2010] [Accepted: 02/23/2011] [Indexed: 12/02/2022] Open
Abstract
Background The presence of four mammalian cell entry (mce) operons in Mycobacterium tuberculosis suggests the essentiality of the functions of the genes in these operons. The differential expression of the four mce operons in different phases of in vitro growth and in infected animals reported earlier from our laboratory further justifies the apparent redundancy for these genes in the genome. Here we investigate the extent of polymorphism in eight genes in the mce1 and mce4 operons of M. tuberculosis from four standard reference strains (H37Rv, H37Ra, LVS (Low Virulent Strain) and BCG) and 112 clinical isolates varying in their drug susceptibility profile, analysed by direct sequencing and Sequenom MassARRAY platform. Results We discovered 20 single nucleotide polymorphisms (SNPs) in the two operons. The comparative analysis of the genes of mce1 and mce4 operons revealed that yrbE1A [Rv0167] was most polymorphic in mce1 operon while yrbE4A [Rv3501c] and lprN [Rv3495c] had the highest number of SNPs in the mce4 operon. Of 20 SNPs, 12 were found to be nonsynonymous and were further analysed for their pathological relevance to M. tuberculosis using web servers PolyPhen and PMut, which predicted five deleterious nonsynonymous SNPs. A mutation from proline to serine at position 359 of the native Mce1A protein was most deleterious as predicted by both PolyPhen and PMut servers. Energy minimization of the structure of native Mce1A protein and mutated protein was performed using InsightII. The mutated Mce1A protein showed structural changes that could account for the effects of this mutation. Conclusions Our results show that SNPs in the coding sequences of mce1 and mce4 operons in clinical isolates can be significantly high. Moreover, mce4 operon is significantly more polymorphic than mce1 operon (p < 0.001). However, the frequency of nonsynonymous substitutions is higher in mce1 operon and synonymous substitutions are more in mce4 operon. In silico modeling predict that nonsynonymous SNP at mce1A [Rv0169], a virulence gene could play a pivotal role in causing functional changes in M. tuberculosis that may reflect upon the biology of the bacteria.
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Affiliation(s)
- Rashmi Pasricha
- Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi-110007, India
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45
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Mammalian cell entry gene family of Mycobacterium tuberculosis. Mol Cell Biochem 2011; 352:1-10. [PMID: 21258845 DOI: 10.1007/s11010-011-0733-5] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2010] [Accepted: 01/10/2011] [Indexed: 01/21/2023]
Abstract
Knowledge of virulence factors is important to understand the microbial pathogenesis and find better antibiotics. Mammalian cell entry (mce) is a crucial protein family for the virulence of Mycobacterium tuberculosis (M. tuberculosis). This review summarized the advances on mce genes. The genomic organization, characteristics of mce genes, phylogeny of this family, and their roles in M. tuberculosis virulence are emphasized in this review.
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Cáceres SM, Ocampo M, Arévalo-Pinzón G, Jimenez RA, Patarroyo ME, Patarroyo MA. The Mycobacterium tuberculosis membrane protein Rv0180c: Evaluation of peptide sequences implicated in mycobacterial invasion of two human cell lines. Peptides 2011; 32:1-10. [PMID: 20883740 DOI: 10.1016/j.peptides.2010.09.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2010] [Revised: 09/21/2010] [Accepted: 09/21/2010] [Indexed: 01/14/2023]
Abstract
The identification and characterization of hypothetical membrane proteins from Mycobacterium tuberculosis have led to a better understanding of the mechanisms used by this pathogen to invade and survive inside host cells. This study assessed the presence, transcription, localization and possible biological activity of the conserved hypothetical protein Rv0180c from M. tuberculosis. Bioinformatics analyses indicated that Rv0180c contains a signal peptide, six possible transmembrane helices and a Plasmodium Export Element (PEXEL)-like motif. PCR analyses showed the presence of the Rv0180c gene in strains from the M. tuberculosis complex; but transcription was not detected in Mycobacterium microti. Sera against synthetic peptides of Rv0180c recognized two protein bands in M. tuberculosis H37Rv sonicate: a ∼48-kDa band close to the predicted molecular mass of Rv0180c (47.6 kDa), and a 63-kDa band probably caused by protein modifications. Moreover, the same sera located the protein on the surface of M. tuberculosis H37Rv bacilli by immunoelectron microscopy. Twenty-three synthetic peptides spanning the entire length of Rv0180c were tested for their ability to bind to U937 and A549 cells, finding nine high-activity binding peptides (HABPs) specific for both cell types, two HABPs specific for A549 cells (namely 31032 and 31044) and two HABPs specific for U937 cells (namely 31025 and 31041). HABPs inhibited invasion of M. tuberculosis H37Rv into A549 or U937 cells by significant percentages and facilitated internalization of latex beads in A549 cells. The Rv0180c HABPs herein reported could be preliminary candidates to be assessed as components of a multiepitope, chemically synthesized, subunit-based vaccine against tuberculosis.
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47
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Meningococcal internalization into human endothelial and epithelial cells is triggered by the influx of extracellular L-glutamate via GltT L-glutamate ABC transporter in Neisseria meningitidis. Infect Immun 2010; 79:380-92. [PMID: 20956569 DOI: 10.1128/iai.00497-10] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Meningococcal internalization into human cells is likely to be a consequence of meningococcal adhesion to human epithelial and endothelial cells. Here, we identified three transposon mutants of Neisseria meningitidis that were primarily defective in the internalization of human brain microvascular endothelial cells (HBMEC), with insertions occurring in the gltT (a sodium-independent L-glutamate transporter) gene or its neighboring gene, NMB1964 (unknown function). NMB1964 was tentatively named gltM in this study because of the presence of a mammalian cell entry (MCE)-related domain in the deduced amino acid sequences. The null ΔgltT-ΔgltM N. meningitidis mutant was also defective in the internalization into human umbilical vein endothelial cells and the human lung carcinoma epithelial cell line A549, and the defect was suppressed by transcomplementation of the mutants with gltT(+)-gltM(+) genes. The intracellular survival of the ΔgltT-ΔgltM mutant in HBMEC was not largely different from that of the wild-type strain under our experimental conditions. Introduction of a1-bp deletion and amber or ochre mutations in gltT-gltM genes resulted in the loss of efficient internalization into HBMEC. The defect in meningococcal internalization into HBMEC and L-glutamate uptake in the ΔgltT-ΔgltM mutant were suppressed only in strains expressing both GltT and GltM proteins. The efficiency of meningococcal invasion to HBMEC decreased under L-glutamate-depleted conditions. Furthermore, ezrin, a key membrane-cytoskeleton linker, accumulated beneath colonies of the gltT(+)-gltM(+) N. meningitidis strain but not of the ΔgltT-ΔgltM mutant. These findings suggest that l-glutamate influx via the GltT-GltM L-glutamate ABC transporter serves as a cue for N. meningitidis internalization into host cells.
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