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Hoelscher M, Barros-Aguirre D, Dara M, Heinrich N, Sun E, Lange C, Tiberi S, Wells C. Candidate anti-tuberculosis medicines and regimens under clinical evaluation. Clin Microbiol Infect 2024:S1198-743X(24)00296-9. [PMID: 38909687 DOI: 10.1016/j.cmi.2024.06.016] [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: 04/15/2024] [Revised: 06/14/2024] [Accepted: 06/15/2024] [Indexed: 06/25/2024]
Abstract
BACKGROUND Tuberculosis (TB) is the leading cause of mortality by an infectious disease world-wide. Despite national and international efforts, the world is not on track to end TB by 2030. Antibiotic treatment of TB is longer than for most infectious diseases and complicated by frequent adverse events. To counter emerging Mycobacterium tuberculosis drug resistance and provide effective, safe drug treatments of shorter duration, novel anti-TB medicines and treatment regimens are needed. Through a joint global effort, more candidate medicines are in the clinical phases of drug development than ever before. OBJECTIVES To review anti-TB medicines and treatment regimens under clinical evaluation for the future treatment of drug-susceptible and drug-resistant TB. SOURCES Pre-clinical and clinical studies on novel anti-TB drugs. CONTENT Description of novel protein synthesis inhibitors (oxazolidinones and oxaboroles), respiratory chain inhibitors (diarylquinolines and cytochrome bc1 complex inhibitor), cell wall inhibitors (DprE1 inhibitors, thioamides and carbapenems) and cholesterol metabolism inhibitor currently evaluated in clinical trials and novel clinical trial platforms for the evaluation of treatment regimens, rather than single entities. IMPLICATIONS A large number of potential anti-TB candidate medicines and innovations in clinical trial design for the evaluation of regimens, rather than single medicines, provide hope for improvements in the treatment of TB.
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Affiliation(s)
- Michael Hoelscher
- Division of Infectious Diseases and Tropical Medicine, LMU University Hospital, LMU Munich, Germany; German Centre for Infection Research, Partner Site Munich, Munich, Germany; Fraunhofer Institute ITMP, Immunology, Infection and Pandemic Research, Munich, Germany; Unit Global Health, Helmholtz Zentrum München, German Research Center for Environmental Health (HMGU), Neuherberg, Germany.
| | | | | | - Norbert Heinrich
- Division of Infectious Diseases and Tropical Medicine, LMU University Hospital, LMU Munich, Germany; German Centre for Infection Research, Partner Site Munich, Munich, Germany; Fraunhofer Institute ITMP, Immunology, Infection and Pandemic Research, Munich, Germany
| | | | - Christoph Lange
- Division of Clinical Infectious Diseases, Research Center Borstel, Borstel, Germany; German Center for Infection Research (DZIF), Partner Site Hamburg-Lübeck-Borstel-Riems, Borstel, Germany; Respiratory Medicine and International Health, University of Lübeck, Lübeck, Germany; Baylor College of Medicine and Texas Children Hospital, Global TB Program, Houston, TX, US
| | - Simon Tiberi
- GSK, Brentford, United Kingdom; Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
| | - Charles Wells
- Bill & Melinda Gates Medical Research Institute, Cambridge, MA, USA
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2
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Xiao Q, Fang S, Ao J, Zhao X, Huang C, Liu Y, Nie Y, Ishiwata A, Tanaka K, Deng W, Ding F. B(C 6F 5) 3-Catalyzed Stereoselective 1,2- cis Arabinofuranosylation with a Conformationally Constrained Donor. ACS OMEGA 2024; 9:11969-11975. [PMID: 38497025 PMCID: PMC10938590 DOI: 10.1021/acsomega.3c09761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 02/19/2024] [Accepted: 02/26/2024] [Indexed: 03/19/2024]
Abstract
Compared with stereoselective glycosylation methods mainly addressed on the preparation of pyranose glycosides, the furanosylation has been more limited, especially for the 1,2-cis arabinofuranosylation. Herein, we report a novel stereoselective 1,2-cis-arabinofuranosylation strategy using a conformationally restricted 3,5-O-xylylene-protected arabinofuranosyl donor on activation with B(C6F5)3 for desired targets in moderate to excellent yields and β-stereoselectivity. The effectiveness of the 1,2-cis-arabinofuranosylation strategy was demonstrated successfully with various acceptors, including carbohydrate alcohols.
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Affiliation(s)
- Qian Xiao
- School
of Pharmaceutical Sciences (Shenzhen), Shenzhen
Campus of Sun Yat-sen University, Shenzhen 518107, China
| | - Sixian Fang
- School
of Pharmaceutical Sciences (Shenzhen), Shenzhen
Campus of Sun Yat-sen University, Shenzhen 518107, China
| | - Jiaming Ao
- School
of Pharmaceutical Sciences (Shenzhen), Shenzhen
Campus of Sun Yat-sen University, Shenzhen 518107, China
| | - Xiaoya Zhao
- School
of Pharmaceutical Sciences (Shenzhen), Shenzhen
Campus of Sun Yat-sen University, Shenzhen 518107, China
| | - Cai Huang
- School
of Pharmaceutical Sciences (Shenzhen), Shenzhen
Campus of Sun Yat-sen University, Shenzhen 518107, China
| | - Yuhua Liu
- School
of Physics and Electronic Engineering, Guangzhou
University, Guangzhou 510006, China
| | - Yichu Nie
- Translational
Medicine Research Institute, First People’s
Hospital of Foshan, Foshan 528000, China
| | - Akihiro Ishiwata
- RIKEN
Cluster for Pioneering Research, Wako, Saitama 3510198, Japan
| | - Katsunori Tanaka
- RIKEN
Cluster for Pioneering Research, Wako, Saitama 3510198, Japan
- Department
of Chemical Science and Engineering, Tokyo
Institute of Technology, Tokyo 152-8552, Japan
| | - Wenbin Deng
- School
of Pharmaceutical Sciences (Shenzhen), Shenzhen
Campus of Sun Yat-sen University, Shenzhen 518107, China
| | - Feiqing Ding
- School
of Pharmaceutical Sciences (Shenzhen), Shenzhen
Campus of Sun Yat-sen University, Shenzhen 518107, China
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3
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Tayal S, Singh V, Bhatnagar S. 3D-QSAR and ADMET studies of morpholino-pyrimidine inhibitors of DprE1 from Mycobacterium tuberculosis. J Biomol Struct Dyn 2023:1-20. [PMID: 38112325 DOI: 10.1080/07391102.2023.2294496] [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: 07/18/2023] [Accepted: 12/01/2023] [Indexed: 12/21/2023]
Abstract
DprE1 is involved in the synthesis of Mycobacterium tuberculosis cell wall and is a potent drug target for Tuberculosis (TB) treatment. The structure and dynamics of the loops L-I and L-II flanking the inhibitor binding site was studied using molecular dynamics (MD) simulation and MMPBSA in Amber v18. Docking and three-dimensional quantitative structure-activity relationship (3D-QSAR) of 55 Morpholino-pyrimidine (MP) inhibitors was carried out using Autodock v1.2.0 and Forge v10. ADMET analysis was done using SwissADME and pkCSM. All MP inhibitors docked in the DprE1 binding pocket, making contacts with L-II residues. MD studies showed that L-I and L-II unfold in the absence of the inhibitor but fold stably structure with reduced protein motions in the presence of MP-38, the highest affinity inhibitor. This was confirmed by k-means clustering and secondary structure analysis. L-II residues, L317, F320 and R325 contributed most towards the MMPBSA binding free energy of MP-38. A robust field-based 3D-QSAR model showed values of r2train = 0.982, r2test = 0.702 and q2 = 0.516. The MP inhibitor field points were broadly divided into negative electrostatics near the A, B rings and hydrophobic electrostatics near the D, E rings. Addition of negative groups at methanone position and ring B as well as addition of hydrophobic and bulky groups at ring E will improve activity. Highly active compounds 47, 49 and 50 of MP series exhibited highly favourable drug-like properties. SAR and ADMET insights attained from this model will help in the development of active DprE1 inhibitors in future.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Sonali Tayal
- Computational and Structural Biology Laboratory, Department of Biological Sciences and Engineering, Netaji Subhas University of Technology, Dwarka, New Delhi, India
| | - Vasundhara Singh
- Computational and Structural Biology Laboratory, Department of Biological Sciences and Engineering, Netaji Subhas University of Technology, Dwarka, New Delhi, India
| | - Sonika Bhatnagar
- Computational and Structural Biology Laboratory, Department of Biological Sciences and Engineering, Netaji Subhas University of Technology, Dwarka, New Delhi, India
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4
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Inaba K, Naito Y, Tachibana M, Toshima K, Takahashi D. Regioselective and Stereospecific β-Arabinofuranosylation by Boron-Mediated Aglycon Delivery. Angew Chem Int Ed Engl 2023; 62:e202307015. [PMID: 37394576 DOI: 10.1002/anie.202307015] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 06/27/2023] [Accepted: 06/30/2023] [Indexed: 07/04/2023]
Abstract
Regio- and stereoselective formation of the 1,2-cis-furanosidic linkage has been in great demand for efficient synthesis of biologically active natural glycosides. In this study, we developed a regioselective and β-stereospecific d-/l-arabinofuranosylation promoted by a boronic acid catalyst under mild conditions. The glycosylations proceeded smoothly for a variety of diols, triols, and unprotected sugar acceptors to give the corresponding β-arabinofuranosides (β-Arbf) in high yields with complete β-stereoselectivity and high regioselectivity. The regioselectivity was completely reversed depending on the optical isomerism of the donor used and was predictable a priori using predictive models. Mechanistic studies based on DFT calculations revealed that the present glycosylation occurs through a highly dissociative concerted SN i mechanism. The usefulness of the glycosylation method was demonstrated by the chemical synthesis of trisaccharide structures of arabinogalactan fragments.
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Affiliation(s)
- Kazuki Inaba
- Department of Applied Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, 223-8522, Japan
| | - Yuna Naito
- Department of Applied Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, 223-8522, Japan
| | - Mina Tachibana
- Department of Applied Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, 223-8522, Japan
| | - Kazunobu Toshima
- Department of Applied Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, 223-8522, Japan
| | - Daisuke Takahashi
- Department of Applied Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, 223-8522, Japan
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5
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Yang J, Zhang L, Qiao W, Luo Y. Mycobacterium tuberculosis: Pathogenesis and therapeutic targets. MedComm (Beijing) 2023; 4:e353. [PMID: 37674971 PMCID: PMC10477518 DOI: 10.1002/mco2.353] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 07/31/2023] [Accepted: 08/03/2023] [Indexed: 09/08/2023] Open
Abstract
Tuberculosis (TB) remains a significant public health concern in the 21st century, especially due to drug resistance, coinfection with diseases like immunodeficiency syndrome (AIDS) and coronavirus disease 2019, and the lengthy and costly treatment protocols. In this review, we summarize the pathogenesis of TB infection, therapeutic targets, and corresponding modulators, including first-line medications, current clinical trial drugs and molecules in preclinical assessment. Understanding the mechanisms of Mycobacterium tuberculosis (Mtb) infection and important biological targets can lead to innovative treatments. While most antitubercular agents target pathogen-related processes, host-directed therapy (HDT) modalities addressing immune defense, survival mechanisms, and immunopathology also hold promise. Mtb's adaptation to the human host involves manipulating host cellular mechanisms, and HDT aims to disrupt this manipulation to enhance treatment effectiveness. Our review provides valuable insights for future anti-TB drug development efforts.
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Affiliation(s)
- Jiaxing Yang
- Center of Infectious Diseases and State Key Laboratory of Biotherapy, West China HospitalSichuan UniversityChengduChina
| | - Laiying Zhang
- Center of Infectious Diseases and State Key Laboratory of Biotherapy, West China HospitalSichuan UniversityChengduChina
| | - Wenliang Qiao
- Department of Thoracic Surgery, West China HospitalSichuan UniversityChengduSichuanChina
- Lung Cancer Center, West China HospitalSichuan UniversityChengduSichuanChina
| | - Youfu Luo
- Center of Infectious Diseases and State Key Laboratory of Biotherapy, West China HospitalSichuan UniversityChengduChina
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6
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Xu X, Dong B, Peng L, Gao C, He Z, Wang C, Zeng J. Anti-tuberculosis drug development via targeting the cell envelope of Mycobacterium tuberculosis. Front Microbiol 2022; 13:1056608. [PMID: 36620019 PMCID: PMC9810820 DOI: 10.3389/fmicb.2022.1056608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 11/25/2022] [Indexed: 12/24/2022] Open
Abstract
Mycobacterium tuberculosis possesses a dynamic cell envelope, which consists of a peptidoglycan layer, a mycolic acid layer, and an arabinogalactan polysaccharide. This envelope possesses a highly complex and unique structure representing a barrier that protects and assists the growth of M. tuberculosis and allows its adaptation to the host. It regulates the immune response of the host cells, causing their damage. Therefore, the cell envelope of M. tuberculosis is an attractive target for vaccine and drug development. The emergence of multidrug-resistant as well as extensively drug resistant tuberculosis and co-infection with HIV prevented an effective control of this disease. Thus, the discovery and development of new drugs is a major keystone for TB treatment and control. This review mainly summarizes the development of drug enzymes involved in the biosynthesis of the cell wall in M. tuberculosis, and other potential drug targets in this pathway, to provide more effective strategies for the development of new drugs.
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Affiliation(s)
- Xinyue Xu
- West China-PUMC CC Chen Institute of Health, West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu, China
| | - Baoyu Dong
- West China-PUMC CC Chen Institute of Health, West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu, China
| | - Lijun Peng
- West China-PUMC CC Chen Institute of Health, West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu, China
| | - Chao Gao
- State Key Laboratory of Biotherapy, Sichuan University, Chengdu, China.,Laboratory of Human Diseases and Immunotherapies, West China Hospital, Sichuan University, Chengdu, China
| | - Zhiqun He
- West China-PUMC CC Chen Institute of Health, West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu, China
| | - Chuan Wang
- West China-PUMC CC Chen Institute of Health, West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu, China
| | - Jumei Zeng
- West China-PUMC CC Chen Institute of Health, West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu, China
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7
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Li H, Yuan J, Duan S, Pang Y. Resistance and tolerance of Mycobacterium tuberculosis to antimicrobial agents-How M. tuberculosis can escape antibiotics. WIREs Mech Dis 2022; 14:e1573. [PMID: 35753313 DOI: 10.1002/wsbm.1573] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 05/22/2022] [Accepted: 05/30/2022] [Indexed: 12/13/2022]
Abstract
Tuberculosis (TB) poses a serious threat to public health worldwide since it was discovered. Until now, TB has been one of the top 10 causes of death from a single infectious disease globally. The treatment of active TB cases majorly relies on various anti-tuberculosis drugs. However, under the selection pressure by drugs, the continuous evolution of Mycobacterium tuberculosis (Mtb) facilitates the emergence of drug-resistant strains, further resulting in the accumulation of tubercle bacilli with multiple drug resistance, especially deadly multidrug-resistant TB and extensively drug-resistant TB. Researches on the mechanism of drug action and drug resistance of Mtb provide a new scheme for clinical management of TB patients, and prevention of drug resistance. In this review, we summarized the molecular mechanisms of drug resistance of existing anti-TB drugs to better understand the evolution of drug resistance of Mtb, which will provide more effective strategies against drug-resistant TB, and accelerate the achievement of the EndTB Strategy by 2035. This article is categorized under: Infectious Diseases > Molecular and Cellular Physiology.
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Affiliation(s)
- Haoran Li
- Department of Bacteriology and Immunology, Beijing Chest Hospital, Capital Medical University/Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China
| | - Jinfeng Yuan
- Department of Bacteriology and Immunology, Beijing Chest Hospital, Capital Medical University/Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China
| | - Shujuan Duan
- School of Medical Technology, Guangdong Medical University, Dongguan, China
| | - Yu Pang
- Department of Bacteriology and Immunology, Beijing Chest Hospital, Capital Medical University/Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China
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8
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Xiong LB, Liu HH, Song L, Dong MM, Ke J, Liu YJ, Liu K, Zhao M, Wang FQ, Wei DZ. Improving the biotransformation efficiency of soybean phytosterols in Mycolicibacterium neoaurum by the combined deletion of fbpC3 and embC in cell envelope synthesis. Synth Syst Biotechnol 2021; 7:453-459. [PMID: 34938904 PMCID: PMC8654695 DOI: 10.1016/j.synbio.2021.11.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 10/27/2021] [Accepted: 11/24/2021] [Indexed: 11/18/2022] Open
Abstract
Biotransformation of soybean phytosterols into 9α-hydroxy-4-androstene-3,17-dione (9-OHAD) by mycobacteria is the core step in the synthesis of adrenocortical hormone. However, the low permeability of the dense cell envelope largely inhibits the overall conversion efficiency of phytosterols. The antigen 85 (Ag85) complex encoded by fbpA, fbpB, and fbpC was proposed as the key factor in the combined catalysis of mycoloyl for producing mycolyl-arabinogalactan (m-AG) and trehalose dimycolate (TDM) in mycobacterial cell envelope. Herein, we confirmed that fbpC3 was essential for the biotransformation of trehalose monomycolate (TMM) to TDM in Mycolicibacterium neoaurum. The deficiency of this gene raised the cell permeability, thereby enhancing the steroid uptake and utilization. The 9-OHAD yield in the fbpC3-deficient 9-OHAD-producing strain was increased by 21.3%. Moreover, the combined deletion of fbpC3 and embC further increased the 9-OHAD yield compared to the single deletion of fbpC3. Finally, after 96 h of bioconversion in industrial resting cells, the 9-OHAD yield of 11.2 g/L was achieved from 20 g/L phytosterols and the productivity reached 0.116 g/L/h. In summary, this study suggested the critical role of the fbpC3 gene in the synthesis of TDM in M. neoaurum and verified the feasibility of improving the bioconversion efficiency of phytosterols through the cell envelope engineering strategy.
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Affiliation(s)
- Liang-Bin Xiong
- Jiading District Central Hospital Affiliated Shanghai University of Medicine and Health Sciences, Shanghai, 201800, PR China
- State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, PR China
- Huawei Safety Evaluation & Medical Research (Shanghai) Co., Ltd., Shanghai, 201206, PR China
| | - Hao-Hao Liu
- State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, PR China
| | - Lu Song
- State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, PR China
| | - Miao-Miao Dong
- State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, PR China
| | - Jie Ke
- State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, PR China
| | - Yong-Jun Liu
- State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, PR China
| | - Ke Liu
- State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, PR China
| | - Ming Zhao
- State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, PR China
- Corresponding author.
| | - Feng-Qing Wang
- State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, PR China
- Huawei Safety Evaluation & Medical Research (Shanghai) Co., Ltd., Shanghai, 201206, PR China
- Corresponding author. State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, PR China.
| | - Dong-Zhi Wei
- State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, PR China
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Taj A, Jia L, Sha S, Wang C, Ullah H, Haris M, Ma X, Ma Y. Functional analysis and enzyme characterization of Mannose-1-phosphate guanylyl transferase (ManB) from Mycobacterium tuberculosis. Res Microbiol 2021; 173:103884. [PMID: 34644596 DOI: 10.1016/j.resmic.2021.103884] [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: 03/20/2021] [Revised: 09/29/2021] [Accepted: 10/01/2021] [Indexed: 10/20/2022]
Abstract
Mycobacterium tuberculosis cell wall consist variety of mannose containing glycoconjugates including lipomannan (LM) and lipoarabinomannan (LAM). These lipoglycans are involved in cell wall integrity and play role in virulence of M. tuberculosis by modulating host immune response. GDP-mannose, required for the synthesis of lipoglycans, is catalyzed by enzyme Mannose-1-phosphate guanylyl transferase (ManB). The enzyme with similar function has been studied in variety of species of prokaryotes and eukaryotes. However, biological role of ManB and its enzymatic activity remains uncharacterized in M. tuberculosis. In present study, we elucidated the role of enzyme by constructing manB knockdown strain of M. tuberculosis H37Ra. The manB knockdown decreased the cell growth and also effected the morphology of M. tuberculosis by altering the permeability of cell membrane. These findings provide the understanding on ManB function and suggesting that ManB could be the potential target for novel anti-tuberculosis drug. Furthermore, we also characterized ManB enzyme by establishing 96 well plate colorimetric assay and determined the kinetic properties including initial velocity, optimum temperature, optimum pH and other kinetic parameters. Our established assay will be helpful for further high throughput screening of potential inhibitors against ManB.
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Affiliation(s)
- Ayaz Taj
- Department of Biochemistry and Molecular Biology, Dalian Medical University, 9 W. Lushun South Road, Dalian, 116044, China.
| | - Liqiu Jia
- Department of Biochemistry and Molecular Biology, Dalian Medical University, 9 W. Lushun South Road, Dalian, 116044, China.
| | - Shanshan Sha
- Department of Biochemistry and Molecular Biology, Dalian Medical University, 9 W. Lushun South Road, Dalian, 116044, China.
| | - Chao Wang
- College of Pharmacy, Dalian Medical University, 9 W. Lushun South Road, Dalian, 116044, China.
| | - Hayan Ullah
- Department of Biochemistry and Molecular Biology, Dalian Medical University, 9 W. Lushun South Road, Dalian, 116044, China.
| | - Muhammad Haris
- Department of Biochemistry and Molecular Biology, Dalian Medical University, 9 W. Lushun South Road, Dalian, 116044, China.
| | - Xiaochi Ma
- College of Pharmacy, Dalian Medical University, 9 W. Lushun South Road, Dalian, 116044, China.
| | - Yufang Ma
- Department of Biochemistry and Molecular Biology, Dalian Medical University, 9 W. Lushun South Road, Dalian, 116044, China; Department of Microbiology, Dalian Medical University, 9 W. Lushun South Road, Dalian, 116044, China.
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10
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Holzheimer M, Buter J, Minnaard AJ. Chemical Synthesis of Cell Wall Constituents of Mycobacterium tuberculosis. Chem Rev 2021; 121:9554-9643. [PMID: 34190544 PMCID: PMC8361437 DOI: 10.1021/acs.chemrev.1c00043] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
![]()
The pathogen Mycobacterium tuberculosis (Mtb), causing
tuberculosis disease, features an extraordinary
thick cell envelope, rich in Mtb-specific lipids,
glycolipids, and glycans. These cell wall components are often directly
involved in host–pathogen interaction and recognition, intracellular
survival, and virulence. For decades, these mycobacterial natural
products have been of great interest for immunology and synthetic
chemistry alike, due to their complex molecular structure and the
biological functions arising from it. The synthesis of many of these
constituents has been achieved and aided the elucidation of their
function by utilizing the synthetic material to study Mtb immunology. This review summarizes the synthetic efforts of a quarter
century of total synthesis and highlights how the synthesis layed
the foundation for immunological studies as well as drove the field
of organic synthesis and catalysis to efficiently access these complex
natural products.
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Affiliation(s)
- Mira Holzheimer
- Stratingh Institute for Chemistry, University of Groningen, 9747 AG Groningen, The Netherlands
| | - Jeffrey Buter
- Stratingh Institute for Chemistry, University of Groningen, 9747 AG Groningen, The Netherlands
| | - Adriaan J Minnaard
- Stratingh Institute for Chemistry, University of Groningen, 9747 AG Groningen, The Netherlands
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11
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High Throughput Expression Screening of Arabinofuranosyltransferases from Mycobacteria. Processes (Basel) 2021. [DOI: 10.3390/pr9040629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Studies on membrane proteins can help to develop new drug targets and treatments for a variety of diseases. However, membrane proteins continue to be among the most challenging targets in structural biology. This uphill endeavor can be even harder for membrane proteins from Mycobacterium species, which are notoriously difficult to express in heterologous systems. Arabinofuranosyltransferases are involved in mycobacterial cell wall synthesis and thus potential targets for antituberculosis drugs. A set of 96 mycobacterial genes coding for Arabinofuranosyltransferases was selected, of which 17 were successfully expressed in E. coli and purified by metal-affinity chromatography. We herein present an efficient high-throughput strategy to screen in microplates a large number of targets from Mycobacteria and select the best conditions for large-scale protein production to pursue functional and structural studies. This methodology can be applied to other targets, is cost and time effective and can be implemented in common laboratories.
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12
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The thick waxy coat of mycobacteria, a protective layer against antibiotics and the host's immune system. Biochem J 2020; 477:1983-2006. [PMID: 32470138 PMCID: PMC7261415 DOI: 10.1042/bcj20200194] [Citation(s) in RCA: 76] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 04/30/2020] [Accepted: 05/04/2020] [Indexed: 12/22/2022]
Abstract
Tuberculosis, caused by the pathogenic bacterium Mycobacterium tuberculosis (Mtb), is the leading cause of death from an infectious disease, with a mortality rate of over a million people per year. This pathogen's remarkable resilience and infectivity is largely due to its unique waxy cell envelope, 40% of which comprises complex lipids. Therefore, an understanding of the structure and function of the cell wall lipids is of huge indirect clinical significance. This review provides a synopsis of the cell envelope and the major lipids contained within, including structure, biosynthesis and roles in pathogenesis.
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Xiang X, Gong Z, Deng W, Sun Q, Xie J. Mycobacterial ethambutol responsive genes and implications in antibiotics resistance. J Drug Target 2020; 29:284-293. [PMID: 33210572 DOI: 10.1080/1061186x.2020.1853733] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Mycobacterium tuberculosis (M. tuberculosis), the causative agent of tuberculosis (TB), remains a formidable threat in mortality and morbidity worldwide. Ethambutol (EMB) is one of the first-line drugs regimens for TB treatment. Arabinosyl transferases are established targets of EMB, which is involved in the biosynthesis of arabinogalactan (AG) and lipoarabinomannan (LAM). Mutations among embCAB operon are responsible for around 70% clinical EMB resistant M. tuberculosis. In this review, we summarised other potential factors associated with EMB resistance via analysing whole genome, proteome and transcriptome of M. tuberculosis exposed to EMB. This will help to design better diagnosis of EMB resistance.
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Affiliation(s)
- Xiaohong Xiang
- School of Pharmacy, Chongqing Medical and Pharmaceutical College, Chongqing, China
| | - Zhen Gong
- State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Institute of Modern Biopharmaceuticals, Southwest University, Chongqing, China
| | - Wanyan Deng
- Department of Infectious Diseases, Key Laboratory of Molecular Biology for Infectious Diseases (Ministry of Education), Institute for Viral Hepatitis, The Second Affiliated Hospital, Chongqing Medical University, Chongqing, China
| | - Qingyu Sun
- State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Institute of Modern Biopharmaceuticals, Southwest University, Chongqing, China
| | - Jianping Xie
- State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Institute of Modern Biopharmaceuticals, Southwest University, Chongqing, China
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14
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Xiong LB, Liu HH, Song XW, Meng XG, Liu XZ, Ji YQ, Wang FQ, Wei DZ. Improving the biotransformation of phytosterols to 9α-hydroxy-4-androstene-3,17-dione by deleting embC associated with the assembly of cell envelope in Mycobacterium neoaurum. J Biotechnol 2020; 323:341-346. [DOI: 10.1016/j.jbiotec.2020.09.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 09/06/2020] [Accepted: 09/20/2020] [Indexed: 10/23/2022]
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15
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Kandasamy S, Palaniyandi K, Gupta UD, Narayanan S. Double deletion of PknI/DacB2 leads to attenuation of Mycobacterium tuberculosis for growth and virulence. Tuberculosis (Edinb) 2020; 123:101957. [PMID: 32741534 DOI: 10.1016/j.tube.2020.101957] [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: 12/24/2019] [Revised: 04/24/2020] [Accepted: 05/05/2020] [Indexed: 11/17/2022]
Abstract
Serine/Threonine Protein Kinases (STPKs) phosphorylates target proteins thereby regulates various important cellular signal transduction pathways such as cell division and cell wall synthesis. It has been demonstrated that the STPKs regulate peptidoglycan biosynthesis by phosphorylating penicillin binding proteins (PBPs). We extensively characterized both PknI (STPK) and DacB2 (PBP) roles individually as well as combining by genetic knockout and phenotypic characterization studies. In the present study, we analyzed the role of PknI and DacB2 in cell division and virulence. The double knockout (DKO) strain growth was reduced under stress conditions like acidic pH, nutrient depletion media and low oxygen availability conditions. We also found that the DKO growth was significantly reduced in macrophage cell line and it was hypersensitive to oxidative and nitrosative stress condition. The DKO strain significantly attenuated in guinea pig model which was measured by reduced bacillary load, gross pathological and histopathological damages. Overall, these results clearly demonstrated that both PknI and DacB2 together play an important role in cell division under stress conditions, the DKO strain significantly attenuated both in vitro and in vivo models.
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Affiliation(s)
- Srinivasan Kandasamy
- Department of Immunology, ICMR-National Institute for Research in Tuberculosis, Chennai, 600031, India
| | - Kannan Palaniyandi
- Department of Immunology, ICMR-National Institute for Research in Tuberculosis, Chennai, 600031, India
| | - Umesh Datta Gupta
- ICMR-National JALMA Institute for Leprosy and Other Mycobacterial Diseases, Agra, 282001, India
| | - Sujatha Narayanan
- Department of Immunology, ICMR-National Institute for Research in Tuberculosis, Chennai, 600031, India.
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16
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Borthwick JA, Alemparte C, Wall I, Whitehurst BC, Argyrou A, Burley G, de Dios-Anton P, Guijarro L, Monteiro MC, Ortega F, Suckling CJ, Pichel JC, Cacho M, Young RJ. Mycobacterium tuberculosis Decaprenylphosphoryl-β-d-ribose Oxidase Inhibitors: Expeditious Reconstruction of Suboptimal Hits into a Series with Potent in Vivo Activity. J Med Chem 2020; 63:2557-2576. [PMID: 31922409 DOI: 10.1021/acs.jmedchem.9b01561] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Decaprenylphosphoryl-β-d-ribose 2'-epimerase (DprE1) is an essential enzyme in Mycobacterium tuberculosis and has recently been studied as a potential drug target, with inhibitors progressing to clinical studies. Here we describe the identification of a novel series of morpholino-pyrimidine DprE1 inhibitors. These were derived from a phenotypic high-throughput screening (HTS) hit with suboptimal physicochemical properties. Optimization strategies included scaffold-hopping, synthesis, and evaluation of fragments of the lead compounds and property-focused optimization. The resulting optimized compounds had much improved physicochemical properties and maintained enzyme and cellular potency. These molecules demonstrated potent efficacy in an in vivo tuberculosis murine infection model.
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Affiliation(s)
- Jennifer A Borthwick
- Medicinal Science and Technology, GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, U.K
| | - Carlos Alemparte
- Global Health R&D, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos, 28760 Madrid, Spain
| | - Ian Wall
- Medicinal Science and Technology, GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, U.K
| | - Benjamin C Whitehurst
- Medicinal Science and Technology, GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, U.K
| | - Argyrides Argyrou
- Medicinal Science and Technology, GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, U.K
| | - Glenn Burley
- Department of Pure & Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, Scotland
| | - Paco de Dios-Anton
- Global Health R&D, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos, 28760 Madrid, Spain
| | - Laura Guijarro
- Global Health R&D, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos, 28760 Madrid, Spain
| | | | - Fatima Ortega
- Global Health R&D, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos, 28760 Madrid, Spain
| | - Colin J Suckling
- Department of Pure & Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, Scotland
| | - Julia Castro Pichel
- Global Health R&D, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos, 28760 Madrid, Spain
| | - Monica Cacho
- Global Health R&D, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos, 28760 Madrid, Spain
| | - Robert J Young
- Medicinal Science and Technology, GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, U.K
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17
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Khosravi AD, Sirous M, Abdi M, Ahmadkhosravi N. Characterization of the most common embCAB gene mutations associated with ethambutol resistance in Mycobacterium tuberculosis isolates from Iran. Infect Drug Resist 2019; 12:579-584. [PMID: 30881063 PMCID: PMC6411316 DOI: 10.2147/idr.s196800] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Introduction Ethambutol (Emb) is one of the first-line drugs in the standard combination therapy for tuberculosis; however, due to the rapid increase in Emb resistance among clinical isolates of Mycobacterium tuberculosis (MTB), early detection of Emb resistance is desirable. As the embCAB operon is considered involved in resistance to Emb, this study aimed to analyze the most common mutations within the embCAB operon among MTB isolates from Iran to find any correlations of these mutations with Emb resistance. Methods A total of 307 clinical isolates of MTB were screened for Emb resistance by phenotypic drug-susceptibility testing. PCR amplification was performed on extracted DNA from all Emb-resistant and randomly selected Emb-susceptible isolates using sets of primers for various gene loci of embC, embA, and embB, followed by sequencing for the detection of most common alterations. Results In total, ten isolates showed resistance to Emb by phenotypic susceptibility testing (3.25%). The mutation rate in ten Emb-resistant MTB strains was 20% (n=2), comprising one mutation in embB (10%), at codon 306 Met–Val and one in embC (10%) at codon 270 Thr–Ile. A nonsynonymous mutation in the embA gene in one of the randomly selected Emb-susceptible isolates located in codon 330 Leu–Leu was also noticed. Conclusion The majority of our Emb-resistant isolates (n=8, 80%) did not demonstrate the sequences investigated within the embCAB operon. As such, these mutations solely are insufficient for the development of complete resistance to Emb in MTB isolates. Additional mechanisms of resistance other than mutations in these sequences studied within the embCAB operon should also be considered.
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Affiliation(s)
- Azar Dokht Khosravi
- Infectious and Tropical Diseases Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.,Department of Microbiology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran,
| | - Mehrandokht Sirous
- Department of Microbiology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran,
| | - Mahtab Abdi
- Department of Microbiology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran,
| | - Nazanin Ahmadkhosravi
- Khuzestan Tuberculosis Regional Reference Laboratory, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
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18
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Raghavendra T, Patil S, Mukherjee R. Peptidoglycan in Mycobacteria: chemistry, biology and intervention. Glycoconj J 2018; 35:421-432. [DOI: 10.1007/s10719-018-9842-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 08/20/2018] [Accepted: 09/05/2018] [Indexed: 01/07/2023]
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19
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Xiong LB, Sun WJ, Liu YJ, Wang FQ, Wei DZ. Enhancement of 9α-Hydroxy-4-androstene-3,17-dione Production from Soybean Phytosterols by Deficiency of a Regulated Intramembrane Proteolysis Metalloprotease in Mycobacterium neoaurum. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2017; 65:10520-10525. [PMID: 29131627 DOI: 10.1021/acs.jafc.7b03766] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Modification of the sterol catabolism pathway in mycobacteria may result in the accumulation of some valuable steroid pharmaceutical intermediates, such as 9α-hydroxy-4-androstene-3,17-dione (9-OHAD). In previous work, sigma factor D (SigD) was identified as a negative factor of the 9-OHAD production in Mycobacterium neoaurum. Here, the deficiency of rip1 putatively coding for a regulated intramembrane proteolysis metalloprotease (Rip1), which could cleave the negative regulator of SigD (anti-SigD), enhanced the transcription of some key genes (choM1, kshA, and hsd4A) in the sterol catabolic pathway. Furthermore, the deletion of rip1 increased the consumption of phytosterols by 37.8% after 96 h of growth in M. neoaurum. The production of 9-OHAD in the engineered M. neoaurumΔkstD1ΔkstD2ΔkstD3Δrip1 (MnΔk123Δrip1) strain was ultimately increased by 27.3% compared to that in its parental strain M. neoaurumΔkstD1ΔkstD2ΔkstD3 (MnΔk123). This study further confirms the important role of SigD-related factors in the catabolism of sterols.
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Affiliation(s)
- Liang-Bin Xiong
- State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology , Shanghai 200237, People's Republic of China
| | - Wan-Ju Sun
- State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology , Shanghai 200237, People's Republic of China
| | - Yong-Jun Liu
- State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology , Shanghai 200237, People's Republic of China
| | - Feng-Qing Wang
- State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology , Shanghai 200237, People's Republic of China
| | - Dong-Zhi Wei
- State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology , Shanghai 200237, People's Republic of China
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20
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Gao Y, Hu X, Wang J, Li H, Wang X. Impact of mycolic acid deficiency on cells of Corynebacterium glutamicum ATCC13869. Biotechnol Appl Biochem 2017; 65:435-445. [PMID: 29072327 DOI: 10.1002/bab.1622] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 10/17/2017] [Indexed: 11/06/2022]
Abstract
Mycolic acid (MA) plays important role in Corynebacterium glutamicum, but the key enzymes in the biosynthetic pathway of MA in C. glutamicum ATCC13869 have not been characterized. Since the locus BBD29_RS14045 in C. glutamicum ATCC13869 shows high similarity to the gene Cgl2871, which encodes Pks13, the key enzyme for synthesizing MA in C. glutamicum ATCC13032, it was deleted, resulting in the mutant WG001. Compared with the wild-type ATCC13869, MA was not synthesized in WG001, but more phosphatidylglycerol and phosphatidylinositol containing longer unsaturated fatty acids were produced. WG001 cells also show hindered cell growth and defective cell separation when compared with ATCC13869 cells. Transcriptomic analysis shows that many genes relevant to the pathways of fatty acids, inositol, phospholipids, cell wall, and cell division were significantly regulated in WG001 cells when compared with ATCC13869 cells. This study demonstrates that the locus BBD29_RS14045 encodes a key enzyme that plays important role for synthesizing MA in C. glutamicum ATCC13869.
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Affiliation(s)
- Yunfei Gao
- School of Biotechnology, Jiangnan University, Wuxi, People's Republic of China
| | - Xiaoqing Hu
- State Key Laboratory of Food Science and Technology, Wuxi, People's Republic of China
| | - Jianli Wang
- School of Biotechnology, Jiangnan University, Wuxi, People's Republic of China
| | - Huazhong Li
- School of Biotechnology, Jiangnan University, Wuxi, People's Republic of China
| | - Xiaoyuan Wang
- School of Biotechnology, Jiangnan University, Wuxi, People's Republic of China.,State Key Laboratory of Food Science and Technology, Wuxi, People's Republic of China
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21
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Xiong LB, Liu HH, Xu LQ, Sun WJ, Wang FQ, Wei DZ. Improving the production of 22-hydroxy-23,24-bisnorchol-4-ene-3-one from sterols in Mycobacterium neoaurum by increasing cell permeability and modifying multiple genes. Microb Cell Fact 2017; 16:89. [PMID: 28532497 PMCID: PMC5440992 DOI: 10.1186/s12934-017-0705-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 05/15/2017] [Indexed: 12/04/2022] Open
Abstract
Background The strategy of modifying the sterol catabolism pathway in mycobacteria has been adopted to produce steroidal pharmaceutical intermediates, such as 22-hydroxy-23,24-bisnorchol-4-ene-3-one (4-HBC), which is used to synthesize various steroids in the industry. However, the productivity is not desirable due to some inherent problems, including the unsatisfactory uptake rate and the low metabolic efficiency of sterols. The compact cell envelope of mycobacteria is a main barrier for the uptake of sterols. In this study, a combined strategy of improving the cell envelope permeability as well as the intracellular sterol metabolism efficiency was investigated to increase the productivity of 4-HBC. Results MmpL3, encoding a transmembrane transporter of trehalose monomycolate, is an important gene influencing the assembly of mycobacterial cell envelope. The disruption of mmpL3 in Mycobacterium neoaurum ATCC 25795 significantly enhanced the cell permeability by 23.4% and the consumption capacity of sterols by 15.6%. Therefore, the inactivation of mmpL3 was performed in a 4-HBC-producing strain derived from the wild type M. neoaurum and the 4-HBC production in the engineered strain was increased by 24.7%. Subsequently, to enhance the metabolic efficiency of sterols, four key genes, choM1, choM2, cyp125, and fadA5, involved in the sterol conversion pathway were individually overexpressed in the engineered mmpL3-deficient strain. The production of 4-HBC displayed the increases of 18.5, 8.9, 14.5, and 12.1%, respectively. Then, the more efficient genes (choM1, cyp125, and fadA5) were co-overexpressed in the engineered mmpL3-deficient strain, and the productivity of 4-HBC was ultimately increased by 20.3% (0.0633 g/L/h, 7.59 g/L 4-HBC from 20 g/L phytosterol) compared with its original productivity (0.0526 g/L/h, 6.31 g/L 4-HBC from 20 g/L phytosterol) in an industrial resting cell bio-transformation system. Conclusions Increasing cell permeability combined with the co-overexpression of the key genes (cyp125, choM1, and fadA5) involved in the conversion pathway of sterol to 4-HBC was effective to enhance the productivity of 4-HBC. The strategy might also be useful for the conversion of sterol to other steroidal intermediates by mycobacteria. Electronic supplementary material The online version of this article (doi:10.1186/s12934-017-0705-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Liang-Bin Xiong
- State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, China
| | - Hao-Hao Liu
- State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, China
| | - Li-Qin Xu
- State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, China
| | - Wan-Ju Sun
- State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, China
| | - Feng-Qing Wang
- State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, China.
| | - Dong-Zhi Wei
- State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, China.
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Joe M, Lowary TL. Synthesis of a homologous series of galactofuranose-containing mycobacterial arabinogalactan fragments. CAN J CHEM 2016. [DOI: 10.1139/cjc-2016-0416] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Mycobacteria, including the human pathogen Mycobacterium tuberculosis, the causative agent of tuberculosis, produce a complex cell wall structure made of carbohydrates and lipids. The major structural element of the mycobacterial cell wall is a glycoconjugate called the mycolic acid – arabinogalactan – peptidoglycan (mAGP) complex. Inhibition of mAGP biosynthesis is a proven strategy for developing anti-mycobacterial drugs, and thus, understanding the pathways and enzymes involved in the assembly of this molecule is of interest. In this paper, we describe the chemical synthesis of a panel of nine oligosaccharide fragments (4–12) of the galactan domain of the mAGP complex designed as biosynthetic probes. These structures, ranging in size from a hexasaccharide to a tetradecasaccharide, are potential substrates for two biosynthetic enzymes, GlfT2 and AftA, and represent the largest mycobacterial galactan fragments synthesized to date. The route developed was iterative and provided multimilligram quantities of the target molecules 4–12 in good overall yield.
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Affiliation(s)
- Maju Joe
- Alberta Glycomics Centre and Department of Chemistry, The University of Alberta, Edmonton, AB T6G 2G2, Canada
- Alberta Glycomics Centre and Department of Chemistry, The University of Alberta, Edmonton, AB T6G 2G2, Canada
| | - Todd L. Lowary
- Alberta Glycomics Centre and Department of Chemistry, The University of Alberta, Edmonton, AB T6G 2G2, Canada
- Alberta Glycomics Centre and Department of Chemistry, The University of Alberta, Edmonton, AB T6G 2G2, Canada
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23
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Lcp1 Is a Phosphotransferase Responsible for Ligating Arabinogalactan to Peptidoglycan in Mycobacterium tuberculosis. mBio 2016; 7:mBio.00972-16. [PMID: 27486192 PMCID: PMC4981717 DOI: 10.1128/mbio.00972-16] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
UNLABELLED Mycobacterium tuberculosis, the etiological agent of tuberculosis (TB), has a unique cell envelope which accounts for its unusual low permeability and contributes to resistance against common antibiotics. The main structural elements of the cell wall consist of a cross-linked network of peptidoglycan (PG) in which some of the muramic acid residues are covalently attached to a complex polysaccharide, arabinogalactan (AG), via a unique α-l-rhamnopyranose-(1→3)-α-d-GlcNAc-(1→P) linker unit. While the molecular genetics associated with PG and AG biosynthetic pathways have been largely delineated, the mechanism by which these two major pathways converge has remained elusive. In Gram-positive organisms, the LytR-CpsA-Psr (LCP) family of proteins are responsible for ligating cell wall teichoic acids to peptidoglycan, through a linker unit that bears a striking resemblance to that found in mycobacterial arabinogalactan. In this study, we have identified Rv3267 as a mycobacterial LCP homolog gene that encodes a phosphotransferase which we have named Lcp1. We demonstrate that lcp1 is an essential gene required for cell viability and show that recombinant Lcp1 is capable of ligating AG to PG in a cell-free radiolabeling assay. IMPORTANCE Tuberculosis is an infectious disease caused by the bacterial organism Mycobacterium tuberculosis Survival of M. tuberculosis rests critically on the integrity of its unique cell wall; therefore, a better understanding of how the genes and enzymes involved in cell wall assembly work is fundamental for us to develop new drugs to treat this disease. In this study, we have identified Lcp1 as an essential phosphotransferase that ligates together arabinogalactan and peptidoglycan, two crucial cell wall macromolecules found within the mycobacterial cell wall. The discovery of Lcp1 sheds new light on the final stages of mycobacterial cell wall assembly and represents a key biosynthetic step that could be exploited for new anti-TB drug discovery.
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24
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Abstract
The cell wall of Mycobacterium tuberculosis is unique in that it differs significantly from those of both Gram-negative and Gram-positive bacteria. The thick, carbohydrate- and lipid-rich cell wall with distinct lipoglycans enables mycobacteria to survive under hostile conditions such as shortage of nutrients and antimicrobial exposure. The key features of this highly complex cell wall are the mycolyl-arabinogalactan-peptidoglycan (mAGP)-based and phosphatidyl-myo-inositol-based macromolecular structures, with the latter possessing potent immunomodulatory properties. These structures are crucial for the growth, viability, and virulence of M. tuberculosis and therefore are often the targets of effective chemotherapeutic agents against tuberculosis. Over the past decade, sophisticated genomic and molecular tools have advanced our understanding of the primary structure and biosynthesis of these macromolecules. The availability of the full genome sequences of various mycobacterial species, including M. tuberculosis, Mycobacterium marinum, and Mycobacterium bovis BCG, have greatly facilitated the identification of large numbers of drug targets and antigens specific to tuberculosis. Techniques to manipulate mycobacteria have also improved extensively; the conditional expression-specialized transduction essentiality test (CESTET) is currently used to determine the essentiality of individual genes. Finally, various biosynthetic assays using either purified proteins or synthetic cell wall acceptors have been developed to study enzyme function. This article focuses on the recent advances in determining the structural details and biosynthesis of arabinogalactan, lipoarabinomannan, and related glycoconjugates.
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25
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Fan X, Duan X, Tong Y, Huang Q, Zhou M, Wang H, Zeng L, Young RF, Xie J. The Global Reciprocal Reprogramming between Mycobacteriophage SWU1 and Mycobacterium Reveals the Molecular Strategy of Subversion and Promotion of Phage Infection. Front Microbiol 2016; 7:41. [PMID: 26858712 PMCID: PMC4729954 DOI: 10.3389/fmicb.2016.00041] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 01/11/2016] [Indexed: 12/20/2022] Open
Abstract
Bacteriophages are the viruses of bacteria, which have contributed extensively to our understanding of life and modern biology. The phage-mediated bacterial growth inhibition represents immense untapped source for novel antimicrobials. Insights into the interaction between mycobacteriophage and Mycobacterium host will inform better utilizing of mycobacteriophage. In this study, RNA sequencing technology (RNA-seq) was used to explore the global response of Mycobacterium smegmatis mc2155 at an early phase of infection with mycobacteriophage SWU1, key host metabolic processes of M. smegmatis mc2155 shut off by SWU1, and the responsible phage proteins. The results of RNA-seq were confirmed by Real-time PCR and functional assay. 1174 genes of M. smegmatis mc2155 (16.9% of the entire encoding capacity) were differentially regulated by phage infection. These genes belong to six functional categories: (i) signal transduction, (ii) cell energetics, (iii) cell wall biosynthesis, (iv) DNA, RNA, and protein biosynthesis, (v) iron uptake, (vi) central metabolism. The transcription patterns of phage SWU1 were also characterized. This study provided the first global glimpse of the reciprocal reprogramming between the mycobacteriophage and Mycobacterium host.
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Affiliation(s)
- Xiangyu Fan
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest UniversityChongqing, China; Department of Biotechnology, School of Biological Science and Technology, University of JinanJinan, China
| | - Xiangke Duan
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University Chongqing, China
| | - Yan Tong
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University Chongqing, China
| | - Qinqin Huang
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University Chongqing, China
| | - Mingliang Zhou
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University Chongqing, China
| | - Huan Wang
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University Chongqing, China
| | - Lanying Zeng
- Department of Biochemistry and Biophysics, Center for Phage Technology, Texas A&M University College Station, TX, USA
| | - Ry F Young
- Department of Biochemistry and Biophysics, Center for Phage Technology, Texas A&M University College Station, TX, USA
| | - Jianping Xie
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University Chongqing, China
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26
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Källenius G, Correia-Neves M, Buteme H, Hamasur B, Svenson SB. Lipoarabinomannan, and its related glycolipids, induce divergent and opposing immune responses to Mycobacterium tuberculosis depending on structural diversity and experimental variations. Tuberculosis (Edinb) 2015; 96:120-30. [PMID: 26586646 DOI: 10.1016/j.tube.2015.09.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 09/16/2015] [Indexed: 01/04/2023]
Abstract
Exposure to Mycobacterium tuberculosis (Mtb) may lead to active or latent tuberculosis, or clearance of Mtb, depending essentially on the quality of the host's immune response. This response is initiated through the interaction of Mtb cell wall surface components, mostly glycolipids, with cells of the innate immune system, particularly macrophages (Mφs) and dendritic cells (DCs). The way Mφs and DC alter their cytokine secretome, activate or inhibit different microbicidal mechanisms and present antigens and consequently trigger the T cell-mediated immune response impacts the host immune response against Mtb. Lipoarabinomannan (LAM) is one of the major cell wall components of Mtb. Mannosyl-capped LAM (ManLAM), and its related cell wall-associated types of glycolipids/lipoglycans, namely phosphatidylinositol mannosides (PIMs) and lipomannan (LM), exhibit important and distinct immunomodulatory properties. The structure, internal heterogeneity and abundance of these molecules vary between Mtb strains exhibiting distinct degrees of virulence. Thus ManLAM, LM and PIMs may be considered crucial Mtb-associated virulence factors in the pathogenesis of tuberculosis. Of particular relevance for this review, there is controversy about the specific immunomodulatory properties of these distinct glycolipids, particularly when tested as purified molecules in vitro. In addition to the variability in the glycolipid composition conflicting reports may also result from differences in the protocols used for glycolipid isolation and for in vitro experiments including immune cell types and procedures to generate them. Understanding the immunomodulatory properties of these cell wall glycolipids, how they differ between distinct Mtb strains, and how they influence the degree of Mtb virulence, is of utmost relevance to understand how the host mounts a protective or otherwise pathologic immune response. This is essential for the design of preventive strategies against tuberculosis. Thus, since clarifying the controversy on this matter is crucial we here review, summarize and discuss reported data from in vitro stimulation with the three major Mtb complex cell wall glycolipids (ManLAM, PIMs and LM) in an attempt to conciliate the conflicting findings.
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Affiliation(s)
- Gunilla Källenius
- Department of Clinical Science and Education, Karolinska Institutet, Södersjukhuset, 118 83 Stockholm, Sweden.
| | - Margarida Correia-Neves
- Department of Clinical Science and Education, Karolinska Institutet, Södersjukhuset, 118 83 Stockholm, Sweden; Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal; ICVS/3B's, PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Helen Buteme
- Department of Clinical Science and Education, Karolinska Institutet, Södersjukhuset, 118 83 Stockholm, Sweden; Department of Medical Microbiology, School of Biomedical Sciences, College of Health Sciences, Makerere University, P.O Box 7072, Kampala, Uganda
| | - Beston Hamasur
- Department of Clinical Science and Education, Karolinska Institutet, Södersjukhuset, 118 83 Stockholm, Sweden
| | - Stefan B Svenson
- Department of Clinical Science and Education, Karolinska Institutet, Södersjukhuset, 118 83 Stockholm, Sweden
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27
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Affiliation(s)
- Monika Jankute
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom;
| | - Jonathan A.G. Cox
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom;
| | - James Harrison
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom;
| | - Gurdyal S. Besra
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom;
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28
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GtrA Protein Rv3789 Is Required for Arabinosylation of Arabinogalactan in Mycobacterium tuberculosis. J Bacteriol 2015; 197:3686-97. [PMID: 26369580 DOI: 10.1128/jb.00628-15] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Accepted: 09/07/2015] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Mycobacterium tuberculosis possesses a thick and highly hydrophobic cell wall principally composed of a mycolyl-arabinogalactan-peptidoglycan complex, which is critical for survival and virulence. DprE1 is a well-characterized component of decaprenyl-phospho-ribose epimerase, which produces decaprenyl-phospho-arabinose (DPA) for the biosynthesis of mycobacterial arabinans. Upstream of dprE1 lies rv3789, which encodes a short transmembrane protein of the GtrA family, whose members are often involved in the synthesis of cell surface polysaccharides. We demonstrate that rv3789 and dprE1 are cotranscribed from a common transcription start site situated 64 bp upstream of rv3789. Topology mapping revealed four transmembrane domains in Rv3789 and a cytoplasmic C terminus consistent with structural models built using analysis of sequence coevolution. To investigate its role, we generated an unmarked rv3789 deletion mutant in M. tuberculosis. The mutant was characterized by impaired growth and abnormal cell morphology, since the cells were shorter and more swollen than wild-type cells. This phenotype likely stems from the decreased incorporation of arabinan into arabinogalactan and was accompanied by an accumulation of DPA. A role for Rv3789 in arabinan biosynthesis was further supported by its interaction with the priming arabinosyltransferase AftA, as demonstrated by a two-hybrid approach. Taken together, the data suggest that Rv3789 does not act as a DPA flippase but, rather, recruits AftA for arabinogalactan biosynthesis. IMPORTANCE Upstream of the essential dprE1 gene, encoding a key enzyme of the decaprenyl phospho-arabinose (DPA) pathway, lies rv3789, coding for a short transmembrane protein of unknown function. In this study, we demonstrated that rv3789 and dprE1 are cotranscribed from a common transcription start site located 64 bp upstream of rv3789 in M. tuberculosis. Furthermore, the deletion of rv3789 led to a reduction in arabinan content and to an accumulation of DPA, confirming that Rv3789 plays a role in arabinan biosynthesis. Topology mapping, structural modeling, and protein interaction studies suggest that Rv3789 acts as an anchor protein recruiting AftA, the first arabinosyl transferase. This investigation provides deeper insight into the mechanism of arabinan biosynthesis in mycobacteria.
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29
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Jankute M, Byng CV, Alderwick LJ, Besra GS. Elucidation of a protein-protein interaction network involved in Corynebacterium glutamicum cell wall biosynthesis as determined by bacterial two-hybrid analysis. Glycoconj J 2015; 31:475-83. [PMID: 25117516 PMCID: PMC4213368 DOI: 10.1007/s10719-014-9549-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Mycobacterium species have a highly complex and unique cell wall that consists of a large macromolecular structure termed the mycolyl-arabinogalactan-peptidoglycan (mAGP) complex. This complex is essential for growth, survival and virulence of the human pathogen Mycobacterium tuberculosis, and is the target of several anti-tubercular drugs. The closely related species Corynebacterium glutamicum has proven useful in the study of orthologous M. tuberculosis genes and proteins involved in mAGP synthesis. This study examines the construction of a protein-protein interaction network for the major cell wall component arabinogalactan in C. glutamicum based on the use of a bacterial two-hybrid system. We have identified twenty-four putative homotypic and heterotypic protein interactions in vivo. Our results demonstrate an association between glycosyltransferases, GlfT1 and AftB, and interaction between the sub-units of decaprenylphosphoribose epimerase, DprE1 and DprE2. These analyses have also shown that AftB interacts with AftA, which catalyzes the addition of the first three arabinose units onto the galactan chain. Both AftA and AftB associate with other arabinofuranosyltransferases, including Emb and AftC, that elongate and branch the arabinan domain. Moreover, a number of proteins involved in arabinogalactan biosynthesis were shown to form dimers or multimers. These findings provide a useful recourse for understanding the biosynthesis and function of the mycobacterial cell wall, as well as providing new therapeutic targets.
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Affiliation(s)
- Monika Jankute
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
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30
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In silico-based high-throughput screen for discovery of novel combinations for tuberculosis treatment. Antimicrob Agents Chemother 2015; 59:5664-74. [PMID: 26149995 PMCID: PMC4538536 DOI: 10.1128/aac.05148-14] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2014] [Accepted: 06/27/2015] [Indexed: 11/20/2022] Open
Abstract
There are currently 18 drug classes for the treatment of tuberculosis, including those in the development pipeline. An in silico simulation enabled combing the innumerably large search space to derive multidrug combinations. Through the use of ordinary differential equations (ODE), we constructed an in silico kinetic platform in which the major metabolic pathways in Mycobacterium tuberculosis and the mechanisms of the antituberculosis drugs were integrated into a virtual proteome. The optimized model was used to evaluate 816 triplets from the set of 18 drugs. The experimentally derived cumulative fractional inhibitory concentration (∑FIC) value was within twofold of the model prediction. Bacterial enumeration revealed that a significant number of combinations that were synergistic for growth inhibition were also synergistic for bactericidal effect. The in silico-based screen provided new starting points for testing in a mouse model of tuberculosis, in which two novel triplets and five novel quartets were significantly superior to the reference drug triplet of isoniazid, rifampin, and ethambutol (HRE) or the quartet of HRE plus pyrazinamide (HREZ).
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31
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Jana M, MacKerell AD. CHARMM Drude Polarizable Force Field for Aldopentofuranoses and Methyl-aldopentofuranosides. J Phys Chem B 2015; 119:7846-59. [PMID: 26018564 DOI: 10.1021/acs.jpcb.5b01767] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
An empirical all-atom CHARMM polarizable force filed for aldopentofuranoses and methyl-aldopentofuranosides based on the classical Drude oscillator is presented. A single electrostatic model is developed for eight different diastereoisomers of aldopentofuranoses by optimizing the existing electrostatic and bonded parameters as transferred from ethers, alcohols, and hexopyranoses to reproduce quantum mechanical (QM) dipole moments, furanose-water interaction energies and conformational energies. Optimization of selected electrostatic and dihedral parameters was performed to generate a model for methyl-aldopentofuranosides. Accuracy of the model was tested by reproducing experimental data for crystal intramolecular geometries and lattice unit cell parameters, aqueous phase densities, and ring pucker and exocyclic rotamer populations as obtained from NMR experiments. In most cases the model is found to reproduce both QM data and experimental observables in an excellent manner, whereas for the remainder the level of agreement is in the satisfactory regimen. In aqueous phase simulations the monosaccharides have significantly enhanced dipoles as compared to the gas phase. The final model from this study is transferrable for future studies on carbohydrates and can be used with the existing CHARMM Drude polarizable force field for biomolecules.
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Affiliation(s)
- Madhurima Jana
- †Department of Pharmaceutical Sciences, University of Maryland, 20 Penn Street HSF II, Baltimore, Maryland 21201, United States.,‡Department of Chemistry, National Institute of Technology Rourkela, Rourkela 769008, Odisha, India
| | - Alexander D MacKerell
- †Department of Pharmaceutical Sciences, University of Maryland, 20 Penn Street HSF II, Baltimore, Maryland 21201, United States
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32
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33
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Kandasamy S, Narayanan S. Phenotypic characterization of a novel double knockout PknI/DacB2 from Mycobacterium tuberculosis. Microbiol Res 2015; 170:255-62. [DOI: 10.1016/j.micres.2014.10.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 09/24/2014] [Accepted: 10/17/2014] [Indexed: 11/30/2022]
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34
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Korkegian A, Roberts DM, Blair R, Parish T. Mutations in the essential arabinosyltransferase EmbC lead to alterations in Mycobacterium tuberculosis lipoarabinomannan. J Biol Chem 2014; 289:35172-81. [PMID: 25352598 DOI: 10.1074/jbc.m114.583112] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The Mycobacterium tuberculosis cell wall is a complex structure essential for the viability of the organism and its interaction with the host. The glycolipid lipoarabinomannan (LAM) plays an important role in mediating host-bacteria interactions and is involved in modulation of the immune response. The arabinosyltransferase EmbC required for LAM biosynthesis is essential. We constructed recombinant strains of M. tuberculosis expressing a variety of alleles of EmbC. We demonstrated that EmbC has a functional signal peptide in M. tuberculosis. Over- or underexpression of EmbC resulted in reduced or increased sensitivity to ethambutol, respectively. The C-terminal domain of EmbC was essential for activity because truncated alleles were unable to mediate LAM production in Mycobacterium smegmatis and were unable to complement an embC deletion in M. tuberculosis. The C-terminal domain of the closely related arabinosyltransferase EmbB was unable to complement the function of the EmbC C-terminal domain. Two functional motifs were identified. The GT-C motif contains two aspartate residues essential for function in the DDX motif. The proline-rich region contains two highly conserved asparagines (Asn-638 and Asn-652). Mutation of these residues was tolerated, but loss of Asn-638 resulted in the synthesis of truncated LAM, which appeared to lack arabinose branching. All embC alleles that were incapable of complementing LAM production in M. smegmatis were not viable in M. tuberculosis, supporting the hypothesis that LAM itself is essential in M. tuberculosis.
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Affiliation(s)
- Aaron Korkegian
- From TB Discovery Research, Infectious Disease Research Institute, Seattle, Washington 98102
| | - David M Roberts
- From TB Discovery Research, Infectious Disease Research Institute, Seattle, Washington 98102
| | - Rachel Blair
- From TB Discovery Research, Infectious Disease Research Institute, Seattle, Washington 98102
| | - Tanya Parish
- From TB Discovery Research, Infectious Disease Research Institute, Seattle, Washington 98102
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35
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Bellinzoni M, Haouz A, Miras I, Magnet S, André-Leroux G, Mukherjee R, Shepard W, Cole ST, Alzari PM. Structural studies suggest a peptidoglycan hydrolase function for the Mycobacterium tuberculosis Tat-secreted protein Rv2525c. J Struct Biol 2014; 188:156-64. [PMID: 25260828 DOI: 10.1016/j.jsb.2014.09.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Revised: 08/08/2014] [Accepted: 09/16/2014] [Indexed: 11/18/2022]
Abstract
Among the few proteins shown to be secreted by the Tat system in Mycobacterium tuberculosis, Rv2525c is of particular interest, since its gene is conserved in the minimal genome of Mycobacterium leprae. Previous evidence linked this protein to cell wall metabolism and sensitivity to β-lactams. We describe here the crystal structure of Rv2525c that shows a TIM barrel-like fold characteristic of glycoside hydrolases of the GH25 family, which includes prokaryotic and phage-encoded peptidoglycan hydrolases. Structural comparison with other members of this family combined with substrate docking suggest that, although the 'neighbouring group' catalytic mechanism proposed for this family still appears as the most plausible, the identity of residues involved in catalysis in GH25 hydrolases might need to be revised.
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Affiliation(s)
- Marco Bellinzoni
- Institut Pasteur, Unité de Microbiologie Structurale and CNRS-UMR3528, 25 rue du Dr. Roux, 75724 Paris Cedex 15, France.
| | - Ahmed Haouz
- Institut Pasteur, Plateforme de Cristallographie (CNRS-UMR3528), 25 rue du Dr. Roux, 75724 Paris Cedex 15, France
| | - Isabelle Miras
- Institut Pasteur, Plateforme de Cristallographie (CNRS-UMR3528), 25 rue du Dr. Roux, 75724 Paris Cedex 15, France
| | - Sophie Magnet
- Global Health Institute, Ecole Polytechnique Fédérale de Lausanne, Station 19, 1015 Lausanne, Switzerland
| | - Gwénaëlle André-Leroux
- Institut Pasteur, Unité de Microbiologie Structurale and CNRS-UMR3528, 25 rue du Dr. Roux, 75724 Paris Cedex 15, France; Unité Mathématique, Informatique et Génome (MIG), INRA, Domaine de Vilvert, 78352 Jouy en Josas Cedex, France
| | - Raju Mukherjee
- Global Health Institute, Ecole Polytechnique Fédérale de Lausanne, Station 19, 1015 Lausanne, Switzerland
| | - William Shepard
- Synchrotron Soleil, L'Orme des Merisiers, Saint-Aubin, 91192 Gif-sur-Yvette Cedex, France
| | - Stewart T Cole
- Global Health Institute, Ecole Polytechnique Fédérale de Lausanne, Station 19, 1015 Lausanne, Switzerland
| | - Pedro M Alzari
- Institut Pasteur, Unité de Microbiologie Structurale and CNRS-UMR3528, 25 rue du Dr. Roux, 75724 Paris Cedex 15, France
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36
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Prozorov AA, Fedorova IA, Bekker OB, Danilenko VN. The virulence factors of Mycobacterium tuberculosis: Genetic control, new conceptions. RUSS J GENET+ 2014. [DOI: 10.1134/s1022795414080055] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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37
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Nobre A, Alarico S, Maranha A, Mendes V, Empadinhas N. The molecular biology of mycobacterial trehalose in the quest for advanced tuberculosis therapies. MICROBIOLOGY-SGM 2014; 160:1547-1570. [PMID: 24858083 DOI: 10.1099/mic.0.075895-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Trehalose is a natural glucose disaccharide identified in the 19th century in fungi and insect cocoons, and later across the three domains of life. In members of the genus Mycobacterium, which includes the tuberculosis (TB) pathogen and over 160 species of nontuberculous mycobacteria (NTM), many of which are opportunistic pathogens, trehalose has been an important focus of research over the last 60 years. It is a crucial player in the assembly and architecture of the remarkable mycobacterial cell envelope as an element of unique highly antigenic glycolipids, namely trehalose dimycolate ('cord factor'). Free trehalose has been detected in the mycobacterial cytoplasm and occasionally in oligosaccharides with unknown function. TB and NTM infection statistics and death toll, the decline in immune responses in the aging population, human immunodeficiency virus/AIDS or other debilitating conditions, and the proliferation of strains with different levels of resistance to the dated drugs in use, all merge into a serious public-health threat urging more effective vaccines, efficient diagnostic tools and new drugs. This review deals with the latest findings on mycobacterial trehalose biosynthesis, catabolism, processing and recycling, as well with the ongoing quest for novel trehalose-related mechanisms to be targeted by novel TB therapeutics. In this context, the drug-discovery pipeline has recently included new lead compounds directed toward trehalose-related targets highlighting the potential of these pathways to stem the tide of rising drug resistance.
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Affiliation(s)
- Ana Nobre
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Susana Alarico
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Ana Maranha
- Biosciences PhD Program, Department of Life Sciences, University of Coimbra, Coimbra, Portugal.,CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Vitor Mendes
- Department of Biochemistry, University of Cambridge, Cambridge, UK.,CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Nuno Empadinhas
- III/UC-Institute for Interdisciplinary Research, University of Coimbra, Coimbra, Portugal.,CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
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38
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Jiménez-Dalmaroni MJ, Radcliffe CM, Harvey DJ, Wormald MR, Verdino P, Ainge GD, Larsen DS, Painter GF, Ulevitch R, Beutler B, Rudd PM, Dwek RA, Wilson IA. Soluble human TLR2 ectodomain binds diacylglycerol from microbial lipopeptides and glycolipids. Innate Immun 2014; 21:175-93. [PMID: 24591200 DOI: 10.1177/1753425914524077] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
TLRs are key innate immune receptors that recognize conserved features of biological molecules that are found in microbes. In particular, TLR2 has been reported to be activated by different kinds of microbial ligands. To advance our understanding of the interaction of TLR2 with its ligands, the recombinant human TLR2 ectodomain (hTLR2ED) was expressed using a baculovirus/insect cell expression system and its biochemical, as well as ligand binding, properties were investigated. The hTLR2ED binds synthetic bacterial and mycoplasmal lipopeptides, lipoteichoic acid from Staphylococcus aureus, and synthetic lipoarabinomannan precursors from Mycobacterium at extracellular physiological conditions, in the absence of its co-receptors TLR1 and TLR6. We also determined that lipopeptides and glycolipids cannot bind simultaneously to hTLR2ED and that the phosphatidyl inositol mannoside 2 (Pim2) is the minimal lipoarabinomannan structure for binding to hTLR2ED. Binding of hTLR2ED to Pim4, which contains a diacylglycerol group with one of its acyl chains containing 19 carbon atoms, indicates that hTLR2ED can bind ligands with acyl chains longer than 16 carbon atoms. In summary, our data indicate that diacylglycerol is the ligand moiety of microbial glycolipids and lipoproteins that bind to hTLR2ED and that both types of ligands bind to the same binding site of hTLR2ED.
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Affiliation(s)
- Maximiliano J Jiménez-Dalmaroni
- Glycobiology Institute, Department of Biochemistry, University of Oxford, Oxford, UK Department of Integrative Structural and Computational Biology, and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Catherine M Radcliffe
- Glycobiology Institute, Department of Biochemistry, University of Oxford, Oxford, UK
| | - David J Harvey
- Glycobiology Institute, Department of Biochemistry, University of Oxford, Oxford, UK
| | - Mark R Wormald
- Glycobiology Institute, Department of Biochemistry, University of Oxford, Oxford, UK
| | - Petra Verdino
- Department of Integrative Structural and Computational Biology, and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Gary D Ainge
- Department of Chemistry, University of Otago, Dunedin, New Zealand
| | - David S Larsen
- Department of Chemistry, University of Otago, Dunedin, New Zealand
| | - Gavin F Painter
- The Ferrier Research Institute, Victoria University Of Wellington, Gracefield Research Centre, Lower Hutt, New Zealand
| | - Richard Ulevitch
- Department of Immunology and Microbial Sciences, The Scripps Research Institute, La Jolla, CA, USA
| | - Bruce Beutler
- Department of Genetics, The Scripps Research Institute, La Jolla, CA, USA
| | - Pauline M Rudd
- Glycobiology Institute, Department of Biochemistry, University of Oxford, Oxford, UK
| | - Raymond A Dwek
- Glycobiology Institute, Department of Biochemistry, University of Oxford, Oxford, UK
| | - Ian A Wilson
- Department of Integrative Structural and Computational Biology, and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA, USA
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Non-replicating Mycobacterium tuberculosis elicits a reduced infectivity profile with corresponding modifications to the cell wall and extracellular matrix. PLoS One 2014; 9:e87329. [PMID: 24516549 PMCID: PMC3916317 DOI: 10.1371/journal.pone.0087329] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2013] [Accepted: 12/20/2013] [Indexed: 12/21/2022] Open
Abstract
A key feature of Mycobacterium tuberculosis is its ability to become dormant in the host. Little is known of the mechanisms by which these bacilli are able to persist in this state. Therefore, the focus of this study was to emulate environmental conditions encountered by M. tuberculosis in the granuloma, and determine the effect of such conditions on the physiology and infectivity of the organism. Non-replicating persistent (NRP) M. tuberculosis was established by the gradual depletion of nutrients in an oxygen-replete and controlled environment. In contrast to rapidly dividing bacilli, NRP bacteria exhibited a distinct phenotype by accumulating an extracellular matrix rich in free mycolate and lipoglycans, with increased arabinosylation. Microarray studies demonstrated a substantial down-regulation of genes involved in energy metabolism in NRP bacteria. Despite this reduction in metabolic activity, cells were still able to infect guinea pigs, but with a delay in the development of disease when compared to exponential phase bacilli. Using these approaches to investigate the interplay between the changing environment of the host and altered physiology of NRP bacteria, this study sheds new light on the conditions that are pertinent to M. tuberculosis dormancy and how this organism could be establishing latent disease.
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40
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Blocking bacterial defences. Nat Chem 2013; 5:642-3. [DOI: 10.1038/nchem.1718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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41
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Abuhammad A, Lowe ED, McDonough MA, Shaw Stewart PD, Kolek SA, Sim E, Garman EF. Structure of arylamineN-acetyltransferase fromMycobacterium tuberculosisdetermined by cross-seeding with the homologous protein fromM. marinum: triumph over adversity. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 2013; 69:1433-46. [DOI: 10.1107/s0907444913015126] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 05/31/2013] [Indexed: 11/10/2022]
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42
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Esin S, Counoupas C, Aulicino A, Brancatisano FL, Maisetta G, Bottai D, Di Luca M, Florio W, Campa M, Batoni G. Interaction ofMycobacterium tuberculosisCell Wall Components with the Human Natural Killer Cell Receptors NKp44 and Toll-Like Receptor 2. Scand J Immunol 2013; 77:460-9. [DOI: 10.1111/sji.12052] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 03/29/2013] [Indexed: 12/30/2022]
Affiliation(s)
- S. Esin
- Department of Translational Research and New Technologies in Medicine and Surgery; University of Pisa; Pisa; Italy
| | - C. Counoupas
- Department of Translational Research and New Technologies in Medicine and Surgery; University of Pisa; Pisa; Italy
| | - A. Aulicino
- Department of Translational Research and New Technologies in Medicine and Surgery; University of Pisa; Pisa; Italy
| | - F. L. Brancatisano
- Department of Translational Research and New Technologies in Medicine and Surgery; University of Pisa; Pisa; Italy
| | - G. Maisetta
- Department of Translational Research and New Technologies in Medicine and Surgery; University of Pisa; Pisa; Italy
| | - D. Bottai
- Department of Translational Research and New Technologies in Medicine and Surgery; University of Pisa; Pisa; Italy
| | - M. Di Luca
- Department of Translational Research and New Technologies in Medicine and Surgery; University of Pisa; Pisa; Italy
| | - W. Florio
- Department of Translational Research and New Technologies in Medicine and Surgery; University of Pisa; Pisa; Italy
| | - M. Campa
- Department of Translational Research and New Technologies in Medicine and Surgery; University of Pisa; Pisa; Italy
| | - G. Batoni
- Department of Translational Research and New Technologies in Medicine and Surgery; University of Pisa; Pisa; Italy
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Lattová E, Svetlíková Z, Mikušová K, Perreault H, Poláková M. Novel synthetic (1 → 6)-α-d-mannodisaccharide substrates support processive mannosylation catalysed by the mycobacterial cell envelope enzyme fraction. RSC Adv 2013. [DOI: 10.1039/c3ra43575j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Mishra AK, Alves JE, Krumbach K, Nigou J, Castro AG, Geurtsen J, Eggeling L, Saraiva M, Besra GS. Differential arabinan capping of lipoarabinomannan modulates innate immune responses and impacts T helper cell differentiation. J Biol Chem 2012; 287:44173-83. [PMID: 23144457 PMCID: PMC3531733 DOI: 10.1074/jbc.m112.402396] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Toll-like receptors (TLRs) recognize pathogens by interacting with pathogen-associated molecular patterns, such as the phosphatidylinositol-based lipoglycans, lipomannan (LM) and lipoarabinomannan (LAM). Such structures are present in several pathogens, including Mycobacterium tuberculosis, being important for the initiation of immune responses. It is well established that the interaction of LM and LAM with TLR2 is a process dependent on the structure of the ligands. However, the implications of structural variations on TLR2 ligands for the development of T helper (Th) cell responses or in the context of in vivo responses are less studied. Herein, we used Corynebacterium glutamicum as a source of lipoglycan intermediates for host interaction studies. In this study, we have deleted a putative glycosyltransferase, NCgl2096, from C. glutamicum and found that it encodes for a novel α(1→2)arabinofuranosyltransferase, AftE. Biochemical analysis of the lipoglycans obtained in the presence (wild type) or absence of NCgl2096 showed that AftE is involved in the biosynthesis of singular arabinans of LAM. In its absence, the resulting molecule is a hypermannosylated (hLM) form of LAM. Both LAM and hLM were recognized by dendritic cells, mainly via TLR2, and triggered the production of several cytokines. hLM was a stronger stimulus for in vitro cytokine production and, as a result, a more potent inducer of Th17 responses. In vivo data confirmed hLM as a stronger inducer of cytokine responses and suggested the involvement of pattern recognition receptors other than TLR2 as sensors for lipoglycans.
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Affiliation(s)
- Arun K Mishra
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
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Rana AK, Singh A, Gurcha SS, Cox LR, Bhatt A, Besra GS. Ppm1-encoded polyprenyl monophosphomannose synthase activity is essential for lipoglycan synthesis and survival in mycobacteria. PLoS One 2012; 7:e48211. [PMID: 23118955 PMCID: PMC3485146 DOI: 10.1371/journal.pone.0048211] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Accepted: 09/26/2012] [Indexed: 02/03/2023] Open
Abstract
The biosynthesis of mycobacterial mannose-containing lipoglycans, such as lipomannan (LM) and the immunomodulator lipoarabinomanan (LAM), is carried out by the GT-C superfamily of glycosyltransferases that require polyprenylphosphate-based mannose (PPM) as a sugar donor. The essentiality of lipoglycan synthesis for growth makes the glycosyltransferase that synthesizes PPM, a potential drug target in Mycobacterium tuberculosis, the causative agent of tuberculosis. In M. tuberculosis, PPM has been shown to be synthesized by Ppm1 in enzymatic assays. However, genetic evidence for its essentiality and in vivo role in LM/LAM and PPM biosynthesis is lacking. In this study, we demonstrate that MSMEG3859, a Mycobacterium smegmatis gene encoding the homologue of the catalytic domain of M. tuberculosis Ppm1, is essential for survival. Depletion of MSMEG3859 in a conditional mutant of M. smegmatis resulted in the loss of higher order phosphatidyl-myo-inositol mannosides (PIMs) and lipomannan. We were also able to demonstrate that two other M. tuberculosis genes encoding glycosyltransferases that either had been shown to possess PPM synthase activity (Rv3779), or were involved in synthesizing similar polyprenol-linked donors (ppgS), were unable to compensate for the loss of MSMEG3859 in the conditional mutant.
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Affiliation(s)
- Amrita K. Rana
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
- School of Chemistry, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Albel Singh
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Sudagar S. Gurcha
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Liam R. Cox
- School of Chemistry, University of Birmingham, Edgbaston, Birmingham, United Kingdom
- * E-mail: (LRC); (AB); (GSB)
| | - Apoorva Bhatt
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
- * E-mail: (LRC); (AB); (GSB)
| | - Gurdyal S. Besra
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
- * E-mail: (LRC); (AB); (GSB)
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