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Rani N, Surolia A. Targeted suppression of MEP pathway genes DXS, IspD and IspF to explore the mycobacterial metabolism and survival. Int J Biol Macromol 2024; 272:132727. [PMID: 38823743 DOI: 10.1016/j.ijbiomac.2024.132727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 05/10/2024] [Accepted: 05/24/2024] [Indexed: 06/03/2024]
Abstract
Due to the uniqueness and essentiality of MEP pathway for the synthesis of crucial metabolites- isoprenoids, hopanoids, menaquinone etc. in mycobacterium, enzymes of this pathway are considered promising anti-tubercular drug targets. In the present study we seek to understand the consequences of downregulation of three of the essential genes- DXS, IspD, and IspF of MEP pathway using CRISPRi approach combined with transcriptomics in Mycobacterium smegmatis. Conditional knock down of either DXS or IspD or IspF gene showed strong bactericidal effect and a profound change in colony morphology. Impaired MEP pathway due to downregulation of these genes increased the susceptibility to frontline anti-tubercular drugs. Further, reduced EtBr accumulation in all the knock down strains in the presence and absence of efflux inhibitor indicated altered cell wall topology. Subsequently, transcriptional analysis validated by qRT-PCR of +154DXS, +128IspD, +104IspF strains showed that modifying the expression of these MEP pathway enzymes affects the regulation of mycobacterial core components. Among the DEGs, expression of small and large ribosomal binding proteins (rpsL, rpsJ, rplN, rplX, rplM, rplS, etc), essential protein translocases (secE, secY and infA, infC), transcriptional regulator (CarD and SigB) and metabolic enzymes (acpP, hydA, ald and fabD) were significantly depleted causing the bactericidal effect. However, mycobacteria survived under these damaging conditions by upregulating mostly the genes needed for the repair of DNA damage (DNA polymerase IV, dinB), synthesis of essential metabolites (serB, LeuA, atpD) and those strengthening the cell wall integrity (otsA, murA, D-alanyl-D-alanine dipeptidase etc.).
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Affiliation(s)
- Nidhi Rani
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560012, India.
| | - Avadhesha Surolia
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560012, India; Dr.Reddy's Institute of Life Science, Hyderabad 500046, India.
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2
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Ahmed S, Chowdhury S, Gomez J, Hung DT, Parish T. Benzene Amide Ether Scaffold is Active against Non-replicating and Intracellular Mycobacterium tuberculosis. ACS Infect Dis 2023; 9:1981-1992. [PMID: 37708378 PMCID: PMC10580325 DOI: 10.1021/acsinfecdis.3c00275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Indexed: 09/16/2023]
Abstract
New drugs to treat tuberculosis which target intractable bacterial populations are required to develop shorter and more effective treatment regimens. The benzene amide ether scaffold has activity against intracellular Mycobacterium tuberculosis, but low activity against extracellular, actively replicating M. tuberculosis. We determined that these molecules have bactericidal activity against non-replicating M. tuberculosis but not actively replicating bacteria. Exposure to compounds depleted ATP levels in non-replicating bacteria and increased the oxygen consumption rate; a subset of molecules led to the accumulation of intrabacterial reactive oxygen species. A comprehensive screen of M. tuberculosis strains identified a number of under-expressing strains as more sensitive to compounds under replicating conditions including QcrA and QcrB hypomorphs. We determined the global gene expression profile after compound treatment for both replicating and nutrient-starved M. tuberculosis. We saw compound-dependent changes in the expression of genes involved in energy metabolism under both conditions. Taken together, our data suggest that the scaffold targets respiration in M. tuberculosis.
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Affiliation(s)
- Sara Ahmed
- TB
Discovery Research, Infectious Disease Research
Institute, Seattle, Washington 98104, United States
- Center
for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington 98109, United States
| | - Sultan Chowdhury
- TB
Discovery Research, Infectious Disease Research
Institute, Seattle, Washington 98104, United States
- Center
for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington 98109, United States
| | - James Gomez
- Broad
Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
| | - Deborah T. Hung
- Broad
Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
| | - Tanya Parish
- TB
Discovery Research, Infectious Disease Research
Institute, Seattle, Washington 98104, United States
- Center
for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington 98109, United States
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3
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Metabolite Dysregulation by Pranlukast in Mycobacterium tuberculosis. Molecules 2022; 27:molecules27051520. [PMID: 35268621 PMCID: PMC8911922 DOI: 10.3390/molecules27051520] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 12/22/2021] [Accepted: 01/15/2022] [Indexed: 02/04/2023] Open
Abstract
Mycobacterium tuberculosis has been infecting millions of people worldwide over the years, causing tuberculosis. Drugs targeting distinct cellular mechanisms including synthesis of the cell wall, lipids, proteins, and nucleic acids in Mtb are currently being used for the treatment of TB. Although extensive research is being carried out at the molecular level in the infected host and pathogen, the identification of suitable drug targets and drugs remains under explored. Pranlukast, an allosteric inhibitor of MtArgJ (Mtb ornithine acetyltransferase) has previously been shown to inhibit the survival and virulence of Mtb. The main objective of this study was to identify the altered metabolic pathways and biological processes associated with the differentially expressed metabolites by PRK in Mtb. Here in this study, metabolomics was carried out using an LC-MS/MS-based approach. Collectively, 50 metabolites were identified to be differentially expressed with a significant p-value through a global metabolomic approach using a high-resolution mass spectrometer. Metabolites downstream of argJ were downregulated in the arginine biosynthetic pathway following pranlukast treatment. Predicted human protein interactors of pranlukast-treated Mtb metabolome were identified in association with autophagy, inflammation, DNA repair, and other immune-related processes. Further metabolites including N-acetylglutamate, argininosuccinate, L-arginine, succinate, ergothioneine, and L-phenylalanine were validated by multiple reaction monitoring, a targeted mass spectrometry-based metabolomic approach. This study facilitates the understanding of pranlukast-mediated metabolic changes in Mtb and holds the potential to identify novel therapeutic approaches using metabolic pathways in Mtb.
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Chellapandi P, Prathiviraj R, Prisilla A. Deciphering structure, function and mechanism of Plasmodium IspD homologs from their evolutionary imprints. J Comput Aided Mol Des 2019; 33:419-436. [DOI: 10.1007/s10822-019-00191-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Accepted: 02/12/2019] [Indexed: 12/17/2022]
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Bartee D, Wheadon MJ, Freel Meyers CL. Synthesis and Evaluation of Fluoroalkyl Phosphonyl Analogues of 2- C-Methylerythritol Phosphate as Substrates and Inhibitors of IspD from Human Pathogens. J Org Chem 2018; 83:9580-9591. [PMID: 29870251 DOI: 10.1021/acs.joc.8b00686] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Targeting essential bacterial processes beyond cell wall, protein, nucleotide, and folate syntheses holds promise to reveal new antimicrobial agents and expand the potential drugs available for combination therapies. The synthesis of isoprenoid precursors, isopentenyl diphosphate (IDP) and dimethylallyl diphosphate (DMADP), is vital for all organisms; however, humans use the mevalonate pathway for production of IDP/DMADP while many pathogens, including Plasmodium falciparum and Mycobacterium tuberculosis, use the orthogonal methylerythritol phosphate (MEP) pathway. Toward developing novel antimicrobial agents, we have designed and synthesized a series of phosphonyl analogues of MEP and evaluated their abilities to interact with IspD, both as inhibitors of the natural reaction and as antimetabolite alternative substrates that could be processed enzymatically to form stable phosphonyl analogues as potential inhibitors of downstream MEP pathway intermediates. In this compound series, the S-monofluoro MEP analogue displays the most potent inhibitory activity against Escherichia coli IspD and is the best substrate for both the E. coli and P. falciparum IspD orthologues with a Km approaching that of the natural substrate for the E. coli enzyme. This work represents a first step toward the development of phosphonyl MEP antimetabolites to modulate early isoprenoid biosynthesis in human pathogens.
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Affiliation(s)
- David Bartee
- Department of Pharmacology and Molecular Sciences , The Johns Hopkins University School of Medicine , Baltimore , Maryland 21205 , United States
| | - Michael J Wheadon
- Department of Pharmacology and Molecular Sciences , The Johns Hopkins University School of Medicine , Baltimore , Maryland 21205 , United States
| | - Caren L Freel Meyers
- Department of Pharmacology and Molecular Sciences , The Johns Hopkins University School of Medicine , Baltimore , Maryland 21205 , United States
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6
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Anti-tubercular drug discovery: in silico implications and challenges. Eur J Pharm Sci 2017; 104:1-15. [PMID: 28341614 DOI: 10.1016/j.ejps.2017.03.028] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 03/08/2017] [Accepted: 03/19/2017] [Indexed: 12/18/2022]
Abstract
Tuberculosis (TB) has been reported as a major public health concern, especially in the developing countries. WHO report on tuberculosis 2016 shows a high mortality rate caused by TB leading to 1.8 million deaths worldwide (including deaths due to TB in HIV positive individuals), which is one of the top 10 causes of mortality in 2015. However, the main therapy used for the treatment of TB is still the Direct Observed Therapy Short-course (DOTS) that consists of four main first-line drugs. Due to the prolonged and unorganized use of these drugs, Mycobacterium tuberculosis (Mtb) has developed drug-resistance against them. To overcome this drug-resistance, efforts are continuously being made to develop new therapeutics. New drug-targets of Mtb are pursued by the researchers to develop their inhibitors. For this, new methodologies that comprise of the computational drug designing techniques are vigorously applied. A major limitation that is found with these techniques is the inability of the newly identified target-based inhibitors to inhibit the whole cell bacteria. A foremost factor for this limitation is the inability of these inhibitors to penetrate the bacterial cell wall. In this regard, various strategies to overcome this limitation have been discussed in detail in this review, along with new targets and new methodologies. A bunch of in silico tools available for the prediction of physicochemical properties that need to be explored to deal with the permeability issue of the Mtb inhibitors has also been discussed.
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Jin Y, Liu Z, Li Y, Liu W, Tao Y, Wang G. A structural and functional study on the 2-C-methyl-d-erythritol-4-phosphate cytidyltransferase (IspD) from Bacillus subtilis. Sci Rep 2016; 6:36379. [PMID: 27821871 PMCID: PMC5099578 DOI: 10.1038/srep36379] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 10/13/2016] [Indexed: 12/25/2022] Open
Abstract
2-C-Methyl-D-erythritol-4-phosphate cytidyltransferase (IspD) is an essential enzyme in the mevalonate-independent pathway of isoprenoid biosynthesis. This enzyme catalyzes 2-C-Methyl-d-erythritol 4-phosphate (MEP) and cytosine triphosphate (CTP) to 4-diphosphocytidyl-2-C-methyl-d-erythritol (CDPME) and inorganic pyrophosphate (PPi). Bacillus subtilis was a kind of excellent isoprene producer. However, the studies on the key enzymes of MEP pathway in B. subtilis were still absent. In this work, the crystal structures of IspD and IspD complexed with CTP from B.subtilis were determined. For the first time, the intact P-loop was observed in the apo structure of IspD enzyme. Structural comparisons revealed that the concerted movements of the P-loop and loops close to the active site were essential in the reaction catalyzed by IspD. Meanwhile, kinetic analysis showed that the CTP hydrolytic activity of IspD from B.subtilis was over two times higher than that from Escherichia coli. These results will be useful for future target-based screening of potential inhibitors and the metabolic engineering for isoprenoid biosynthesis.
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Affiliation(s)
- Yun Jin
- Key Laboratory of Environmental and Applied Microbiology, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, China.,Key Laboratory of Environmental Microbiology of Sichuan Province, Chengdu, 610041, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhongchuan Liu
- Key Laboratory of Environmental and Applied Microbiology, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, China.,Key Laboratory of Environmental Microbiology of Sichuan Province, Chengdu, 610041, China
| | - Yanjie Li
- Key Laboratory of Environmental and Applied Microbiology, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, China.,Key Laboratory of Environmental Microbiology of Sichuan Province, Chengdu, 610041, China
| | - Weifeng Liu
- Chinese Academy of Sciences Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China
| | - Yong Tao
- Chinese Academy of Sciences Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China
| | - Ganggang Wang
- Key Laboratory of Environmental and Applied Microbiology, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, China.,Key Laboratory of Environmental Microbiology of Sichuan Province, Chengdu, 610041, China
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8
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Abstract
This article summarizes what is currently known of the structures, physiological roles, involvement in pathogenicity, and biogenesis of a variety of noncovalently bound cell envelope lipids and glycoconjugates of Mycobacterium tuberculosis and other Mycobacterium species. Topics addressed in this article include phospholipids; phosphatidylinositol mannosides; triglycerides; isoprenoids and related compounds (polyprenyl phosphate, menaquinones, carotenoids, noncarotenoid cyclic isoprenoids); acyltrehaloses (lipooligosaccharides, trehalose mono- and di-mycolates, sulfolipids, di- and poly-acyltrehaloses); mannosyl-beta-1-phosphomycoketides; glycopeptidolipids; phthiocerol dimycocerosates, para-hydroxybenzoic acids, and phenolic glycolipids; mycobactins; mycolactones; and capsular polysaccharides.
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Brown AC, Kokoczka R, Parish T. LytB1 and LytB2 of Mycobacterium tuberculosis Are Not Genetically Redundant. PLoS One 2015; 10:e0135638. [PMID: 26309039 PMCID: PMC4550268 DOI: 10.1371/journal.pone.0135638] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Accepted: 07/23/2015] [Indexed: 11/26/2022] Open
Abstract
Mycobacterium tuberculosis synthesises isoprenoid precursors via the MEP/DOXP pathway and at least five enzymes in the pathway (Dxs1, Dxr/IspC, IspD, IspF, and GcpE/IspG) are required for growth in vitro. We investigated the role of LytB (IspH) in M. tuberculosis; M. tuberculosis is unusual in that it has two homologs–LytB1 and LytB2. We were unable to delete the lytB2 gene unless we provided an additional copy elsewhere, demonstrating that this is the essential homolog. We expressed lytB1 from the lytB2 promoter and confirmed that this could not complement for loss of function of lytB2, despite LytB1 possessing all the previously described conserved critical residues. Interestingly the sole LytB homolog of Mycobacterium smegmatis was able to compensate for loss of LytB2 in M. tuberculosis. We tested translational fusions of LytB1 and LytB2 for functionality in M. tuberculosis, but only a fusion with 90% N-terminal LytB2 and 10% C-terminal LytB1 was functional. In order to identify the key difference between the two proteins, site directed mutagenesis was used to change LytB2 residues into their counterparts in LytB1. None of these amino acid substitutions was essential for function and all lytB2 mutant alleles were functional. In contrast, mutation of the key residues for [Fe4S4] cluster formation, as well as a catalytic residue in LytB1 did not result in functional complementation. Thus, although LytB1 and LytB2 are not genetically redundant, this is not dependent on small amino acid changes, but is likely to be a result of major overall structural differences.
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Affiliation(s)
- Amanda Claire Brown
- Queen Mary University of London, London, E1 2AD, United Kingdom
- Barts & the London School of Medicine and Dentistry, London, E1 2AD, United Kingdom
| | - Rachel Kokoczka
- TB Discovery Research, Infectious Disease Research Institute, Seattle, WA, 98102, United States of America
| | - Tanya Parish
- Queen Mary University of London, London, E1 2AD, United Kingdom
- Barts & the London School of Medicine and Dentistry, London, E1 2AD, United Kingdom
- TB Discovery Research, Infectious Disease Research Institute, Seattle, WA, 98102, United States of America
- * E-mail:
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10
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Angala SK, Belardinelli JM, Huc-Claustre E, Wheat WH, Jackson M. The cell envelope glycoconjugates of Mycobacterium tuberculosis. Crit Rev Biochem Mol Biol 2014; 49:361-99. [PMID: 24915502 PMCID: PMC4436706 DOI: 10.3109/10409238.2014.925420] [Citation(s) in RCA: 107] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Tuberculosis (TB) remains the second most common cause of death due to a single infectious agent. The cell envelope of Mycobacterium tuberculosis (Mtb), the causative agent of the disease in humans, is a source of unique glycoconjugates and the most distinctive feature of the biology of this organism. It is the basis of much of Mtb pathogenesis and one of the major causes of its intrinsic resistance to chemotherapeutic agents. At the same time, the unique structures of Mtb cell envelope glycoconjugates, their antigenicity and essentiality for mycobacterial growth provide opportunities for drug, vaccine, diagnostic and biomarker development, as clearly illustrated by recent advances in all of these translational aspects. This review focuses on our current understanding of the structure and biogenesis of Mtb glycoconjugates with particular emphasis on one of the most intriguing and least understood aspect of the physiology of mycobacteria: the translocation of these complex macromolecules across the different layers of the cell envelope. It further reviews the rather impressive progress made in the last 10 years in the discovery and development of novel inhibitors targeting their biogenesis.
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Affiliation(s)
- Shiva Kumar Angala
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University , Fort Collins, CO , USA
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11
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Tomioka H, Tatano Y, Yasumoto K, Shimizu T. Recent advances in antituberculous drug development and novel drug targets. Expert Rev Respir Med 2014; 2:455-71. [DOI: 10.1586/17476348.2.4.455] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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12
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Cai L, Zhao X, Jiang T, Qiu J, Owusu L, Ma Y, Wang B, Xin Y. Prokaryotic Expression, Identification and Bioinformatics Analysis of the Mycobacterium tuberculosis Rv3807c Gene Encoding the Putative Enzyme Committed to Decaprenylphosphoryl-d-arabinose Synthesis. Indian J Microbiol 2013; 54:46-51. [PMID: 24426166 DOI: 10.1007/s12088-013-0418-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 05/21/2013] [Indexed: 11/25/2022] Open
Abstract
Decaprenylphosphoryl-d-arabinofuranosyl (DPA), the immediate donor for the polymerized d-Araf residues of mycobacterial arabinan, is synthesized from 5-phosphoribose-1-diphosphate (PRPP) in three-step reactions. (i) PRPP is transferred to decaprenyl-phosphate (DP) to form decaprenylphosphoryl-d-5-phosphoribose (DPPR). (ii) DPPR is dephosphorylated to form decaprenylphosphoryl-d-ribose (DPR). (iii) DPR is formed to DPA by the epimerase. Mycobacterium tuberculosis Rv3806c and heteromeric Rv3790/Rv3791 have been identified as the PRPP: decaprenyl-phosphate 5-phosphoribosyltransferase and the epimerase respectively. Rv3807c, however, as the candidate of phospholipid phosphatase, catalyzing the biosynthesis of decapreny-l-phosphoryl-ribose (DPR) from decaprenylphosphoryl-β-d-5-phosphoribose by dephosphorylating, has no direct experimental evidence of its essentiality in any species of mycobacterium. In this study, Rv3807c gene was amplified from the genome of M. tuberculosis H37Rv by PCR, and was successfully expressed in Escherichia coli BL21 (DE3) via the recombinant plasmid pColdII-Rv3807c. The resulting protein with the 6× His-tag was identified by SDS-PAGE and Western blotting. The protein was predicted through bioinformatics to contain three transmembrane domains, the N-terminal peptide, and a core structure with phosphatidic acid phosphatase type2/haloperoxidase. This study provides biochemical and bioinformatics evidence for the importance of Rv3807c in mycobacteria, and further functional studies will be conducted for validating Rv3807c as a promising phospholipid phosphatase in the synthetic pathway of DPA.
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Affiliation(s)
- Lina Cai
- Department of Biotechnology, Dalian Medical University, Dalian, 116044 People's Republic of China
| | - Xiaojiao Zhao
- TB Laboratory of Shenyang Chest Hospital, Shenyang, 110044 People's Republic of China
| | - Tao Jiang
- Department of Biotechnology, Dalian Medical University, Dalian, 116044 People's Republic of China
| | - Juanjuan Qiu
- Department of Biotechnology, Dalian Medical University, Dalian, 116044 People's Republic of China
| | - Lawrence Owusu
- Department of Biotechnology, Dalian Medical University, Dalian, 116044 People's Republic of China
| | - Yufang Ma
- Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian, 116044 People's Republic of China
| | - Bo Wang
- Department of Pathology, Dalian Medical University, Dalian, 116044 People's Republic of China
| | - Yi Xin
- Department of Biotechnology, Dalian Medical University, Dalian, 116044 People's Republic of China
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Odejinmi SI, Rascon RG, Chen W, Lai K. Formal Synthesis of 4-diphosphocytidyl-2-C-methyl D-erythritol From D-(+)-Arabitol. Tetrahedron 2012; 68:8937-8941. [PMID: 23049145 PMCID: PMC3462025 DOI: 10.1016/j.tet.2012.08.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
2-C-methyl-D-erythritol-4-phosphate (MEP) is a key chemical intermediate of the non-mevalonate pathway for isoprenoid biosynthesis employed by many pathogenic microbes. MEP is also the precursor for the synthesis of 4-diphosphocytidyl-2-C-methyl D-erythritol (CDP-ME), another key intermediate of the non-mevalonate pathway. As this pathway is non-existent in higher animals, including humans, it represents great opportunities for novel antimicrobial development. To facilitate the in-depth studies of this pathway, we reported here a formal synthesis of CDP-ME through a new synthesis of 2-C-Methyl-D-erythritol-4-phosphoric acid from D-(+)-arabitol.
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Affiliation(s)
- Sina I. Odejinmi
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT 84132, U.S.A
| | - Rafael G. Rascon
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT 84132, U.S.A
| | - Wyman Chen
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT 84132, U.S.A
| | - Kent Lai
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT 84132, U.S.A
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Gao P, Yang Y, Xiao C, Liu Y, Gan M, Guan Y, Hao X, Meng J, Zhou S, Chen X, Cui J. Identification and validation of a novel lead compound targeting 4-diphosphocytidyl-2-C-methylerythritol synthetase (IspD) of mycobacteria. Eur J Pharmacol 2012; 694:45-52. [PMID: 22975264 DOI: 10.1016/j.ejphar.2012.08.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Revised: 08/21/2012] [Accepted: 08/27/2012] [Indexed: 01/17/2023]
Abstract
Tuberculosis is a serious threat to world-wide public health usually caused in humans by Mycobacterium tuberculosis (M. tuberculosis). It exclusively utilizes the methylerythritol phosphate (MEP) pathway for biosynthesis of isopentenyl diphosphate (IPP) and its isomer dimethylallyl diphosphate (DMAPP), the precursors of all isoprenoid compounds. The 4-diphosphocytidyl-2-C-methyl-D-erythritol synthase (IspD; EC 2.7.7.60) is the key enzyme of the MEP pathway. It is also of interest as a new chemotherapeutic target, as the enzyme is absent in mammals and ispD is an essential gene for growth. A high-throughput screening method was therefore developed to identify compounds that inhibit IspD. This process was applied to identify a lead compound, domiphen bromide (DMB), that may effectively inhibit IspD. The inhibitory action of DMB was confirmed by over-expressing or down-regulating IspD in Mycobacterium smegmatis (M. smegmatis), demonstrating that DMB inhibit M. smegmatis growth additionally through an IspD-independent pathway. This also led to higher levels of growth inhibition when combined with IspD knockdown. This novel IspD inhibitor was also reported to exhibit antimycobacterial activity in vitro, an effect that likely occurs as a result of perturbation of cell wall biosynthesis.
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Affiliation(s)
- Peng Gao
- Department of Microbiology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
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15
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Ponaire S, Zinglé C, Tritsch D, Grosdemange-Billiard C, Rohmer M. Growth inhibition of Mycobacterium smegmatis by prodrugs of deoxyxylulose phosphate reducto-isomerase inhibitors, promising anti-mycobacterial agents. Eur J Med Chem 2012; 51:277-85. [DOI: 10.1016/j.ejmech.2012.02.031] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 02/15/2012] [Accepted: 02/16/2012] [Indexed: 10/28/2022]
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16
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Gräwert T, Groll M, Rohdich F, Bacher A, Eisenreich W. Biochemistry of the non-mevalonate isoprenoid pathway. Cell Mol Life Sci 2011; 68:3797-814. [PMID: 21744068 PMCID: PMC11114746 DOI: 10.1007/s00018-011-0753-z] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2011] [Revised: 05/26/2011] [Accepted: 06/14/2011] [Indexed: 02/08/2023]
Abstract
The non-mevalonate pathway of isoprenoid (terpenoid) biosynthesis is essential in many eubacteria including the major human pathogen, Mycobacterium tuberculosis, in apicomplexan protozoa including the Plasmodium spp. causing malaria, and in the plastids of plants. The metabolic route is absent in humans and is therefore qualified as a promising target for new anti-infective drugs and herbicides. Biochemical and structural knowledge about all enzymes involved in the pathway established the basis for discovery and development of inhibitors by high-throughput screening of compound libraries and/or structure-based rational design.
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Affiliation(s)
- Tobias Gräwert
- Department Chemie, Lehrstuhl für Biochemie, Center for Integrated Protein Science München, Technische Universität München, Lichtenbergstr. 4, 85747 Garching, Germany
| | - Michael Groll
- Department Chemie, Lehrstuhl für Biochemie, Center for Integrated Protein Science München, Technische Universität München, Lichtenbergstr. 4, 85747 Garching, Germany
| | | | - Adelbert Bacher
- Department Chemie, Lehrstuhl für Biochemie, Center for Integrated Protein Science München, Technische Universität München, Lichtenbergstr. 4, 85747 Garching, Germany
| | - Wolfgang Eisenreich
- Department Chemie, Lehrstuhl für Biochemie, Center for Integrated Protein Science München, Technische Universität München, Lichtenbergstr. 4, 85747 Garching, Germany
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Tsang A, Seidle H, Jawaid S, Zhou W, Smith C, Couch RD. Francisella tularensis 2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase: kinetic characterization and phosphoregulation. PLoS One 2011; 6:e20884. [PMID: 21694781 PMCID: PMC3111433 DOI: 10.1371/journal.pone.0020884] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2011] [Accepted: 05/11/2011] [Indexed: 11/29/2022] Open
Abstract
Deliberate and natural outbreaks of infectious disease, the prevalence of antibiotic resistant strains, and the ease by which antibiotic resistant bacteria can be intentionally engineered all underscore the necessity of effective vaccines and continued development of novel antimicrobial/antiviral therapeutics. Isoprenes, a group of molecules fundamentally involved in a variety of crucial biological functions, are derived from either the mevalonic acid (MVA) or methylerythritol phosphate (MEP) pathway. While mammals utilize the MVA pathway, many bacteria utilize the MEP pathway, highlighting the latter as an attractive target for antibiotic development. In this report we describe the cloning and characterization of Francisella tularensis MEP cytidylyltransferase, a MEP pathway enzyme and potential target for antibiotic development. Size exclusion chromatography indicates the protein exists as a dimer in solution. Enzyme assays produced an apparentK(MEP)(M) = 178 μM, K(CTP)(M) = 73 μM , k(MEP)(cat) = 1(s-1), k(CTP)(cat) = 0.8( s-1), and a k(MEP)(cat)/ K(MEP)(M) = 3.4 x 10(5) M(-1) min(-1). The enzyme exhibits a strict preference for Mg(+2) as a divalent cation and CTP as the nucleotide. Titanium dioxide chromatography-tandem mass spectrometry identified Thr141 as a site of phosphorylation. T141D and T141E site-directed mutants are catalytically inactive, suggesting a mechanism for post-translational control of metabolic flux through the F. tularensis MEP pathway. Overall, our study suggests that MEP cytidylyltransferase is an excellent target for the development of novel antibiotics against F. tularensis.
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Affiliation(s)
- Arthur Tsang
- Department of Chemistry and Biochemistry, George Mason University, Manassas, Virginia, United States of America
- National Center for Biodefense and Infectious Diseases, George Mason University, Manassas, Virginia, United States of America
| | - Heather Seidle
- Department of Chemistry and Biochemistry, George Mason University, Manassas, Virginia, United States of America
- National Center for Biodefense and Infectious Diseases, George Mason University, Manassas, Virginia, United States of America
| | - Safdar Jawaid
- Department of Chemistry and Biochemistry, George Mason University, Manassas, Virginia, United States of America
- National Center for Biodefense and Infectious Diseases, George Mason University, Manassas, Virginia, United States of America
| | - Weidong Zhou
- Department of Molecular and Microbiology, George Mason University, Manassas, Virginia, United States of America
- Center for Applied Proteomics and Molecular Medicine, George Mason University, Manassas, Virginia, United States of America
| | - Clint Smith
- Geospatial Research and Engineering Division, U.S. Army Engineer Research and Development Center, Alexandria, Virginia, United States of America
| | - Robin D. Couch
- Department of Chemistry and Biochemistry, George Mason University, Manassas, Virginia, United States of America
- National Center for Biodefense and Infectious Diseases, George Mason University, Manassas, Virginia, United States of America
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Björkelid C, Bergfors T, Henriksson LM, Stern AL, Unge T, Mowbray SL, Jones TA. Structural and functional studies of mycobacterial IspD enzymes. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 2011; 67:403-14. [PMID: 21543842 DOI: 10.1107/s0907444911006160] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Accepted: 02/18/2011] [Indexed: 11/10/2022]
Abstract
A number of pathogens, including the causative agents of tuberculosis and malaria, synthesize isopentenyl diphosphate via the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway rather than the classical mevalonate pathway found in humans. As part of a structure-based drug-discovery program against tuberculosis, IspD, the enzyme that carries out the third step in the MEP pathway, was targeted. Constructs of both the Mycobacterium smegmatis and the Mycobacterium tuberculosis enzymes that were suitable for structural and inhibitor-screening studies were engineered. Two crystal structures of the M. smegmatis enzyme were produced, one in complex with CTP and the other in complex with CMP. In addition, the M. tuberculosis enzyme was crystallized in complex with CTP. Here, the structure determination and crystallographic refinement of these crystal forms and the enzymatic characterization of the M. tuberculosis enzyme construct are reported. A comparison with known IspD structures allowed the definition of the structurally conserved core of the enzyme. It indicates potential flexibility in the enzyme and in particular in areas close to the active site. These well behaved constructs provide tools for future target-based screening of potential inhibitors. The conserved nature of the extended active site suggests that any new inhibitor will potentially exhibit broad-spectrum activity.
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Affiliation(s)
- Christofer Björkelid
- Department of Cell and Molecular Biology, Uppsala University, Biomedical Center, Box 596, SE-75124 Uppsala, Sweden
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Insight into human alveolar macrophage and M. tuberculosis interactions via metabolic reconstructions. Mol Syst Biol 2011; 6:422. [PMID: 20959820 PMCID: PMC2990636 DOI: 10.1038/msb.2010.68] [Citation(s) in RCA: 195] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2010] [Accepted: 07/30/2010] [Indexed: 02/06/2023] Open
Abstract
A human alveolar macrophage genome-scale metabolic reconstruction was reconstructed from tailoring a global human metabolic network, Recon 1, by using computational algorithms and manual curation. A genome-scale host–pathogen network of the human alveolar macrophage and Mycobacterium tuberculosis is presented. This involved integrating two genome-scale network reconstructions. The reaction activity and gene essentiality predictions of the host–pathogen model represent a more accurate depiction of infection. Integration of high-throughput data into a host-pathogen model followed by systems analysis was performed in order to elucidate major metabolic differences under different types of M. tuberculosis infection.
Mycobacterium tuberculosis (M. tb) is an insidious and highly persistent pathogen that affects one-third of the world's population (WHO, 2009). Metabolism is foundational to M. tb's infection ability and the ensuing host–pathogen interactions. In addition, M. tb has a heterogeneous clinical presentation and can infect virtually every tissue. Depending on the location of the infection, different metabolic pathways are active and inactive in both the host and pathogen cells. In this study, we sought to model the host–pathogen interactions of the human alveolar macrophage and M. tb as well as detail the metabolic differences in specific infection types using genome-scale metabolic reconstructions (Figure 4A). Genome-scale metabolic reconstructions are knowledge bases of all known metabolic reactions of a given organism. Reconstructions have been shown to elucidate the mechanistic genotype-to-phenotype relationship through the integration of high-throughput and physiological data (Oberhardt et al, 2009). Genome-scale reconstructions are converted into mathematical models under the constraints-based reconstruction and analysis (COBRA) platform (Becker et al, 2007). COBRA models use network stoichiometry and steady-state mass balances to define a solution space of potential flux states that a network can take. Thus, the COBRA approach does not require kinetic parameters. Recently, the global human metabolic network, Recon 1, has been reconstructed (Duarte et al, 2007). To understand the metabolic host–pathogen integrations of M. tb with its human host, we first tailored the global human metabolic network into a cell-specific metabolic reconstruction of the human alveolar macrophage. This was carried out using established computational algorithms (Becker and Palsson, 2008; Shlomi et al, 2008) and manual curation to confirm the included and excluded reactions. The human alveolar macrophage reconstruction, iAB-AMØ-1410, accounts for 1410 genes, 3012 intracellular reactions, and 2572 metabolites (Figure 4C). iAB-AMØ-1410 was able to accurately predict maximum ATP and NO production rates obtained from experimental data (Griscavage et al, 1993; Newsholme et al, 1999). The second step to studying host–pathogen interactions was integration of the human alveolar macrophage reconstruction with an existing genome-scale metabolic model of M. tb, iNJ661 (Jamshidi and Palsson, 2007). Interfacial constraints were set to create a phagosomal environment that was hypoxic, nitrosative, rich in fatty acids, and poor in carbohydrates. From the onset, it was apparent that some oxygen (<15% of in vitro uptake) was required for proper simulations. In addition, algorithmic tailoring of the M. tb biomass objective function was performed to better represent an infectious state. The integrated host–pathogen metabolic reconstruction was dubbed iAB-AMØ-1410-Mt-661. Analysis of the integrated host–pathogen metabolic reconstruction resulted in three main findings. First, by setting interfacial constraints and tailoring the biomass objective function, the solution space better represents an infectious state. Without adding artificial constraints to the host portion of the integrated model, the iAB-AMØ-1410 solution space is greatly reduced (Figure 4B). Macrophage glycolysis and nitric oxide production are up-regulated and macrophage ATP production, nucleotide synthesis, and amino-acid metabolism are suppressed. In addition, M. tb glycolysis is suppressed and isocitrate lyase is up-regulated for generation of acetyl-CoA. Fatty acid oxidation pathways and production of mycolic acids are increased, while production of nucleotides, peptidoglycans, and phenolic glycolipids are reduced. The modified solution space of the alveolar macrophage and M. tb better represents the infectious state. Second, the host-pathogen model more accurately predicts M. tb gene deletion tests than the current in vitro model, iNJ661. The host-pathogen model predicted 11 essential genes and 37 unessential genes differently than iNJ661. A total of 22 of the differentially predicted genes have been experimentally characterized (Sassetti and Rubin, 2003; Sohaskey, 2008). The host-pathogen model correctly predicted 18 of the 22 genes. Thus, iAB-AMØ-1410-Mt-661 is a more accurate platform for studying infectious states of M. tb. Finally, we sought to determine metabolic differences in both the macrophage and M. tb between three different types of infection: latent, pulmonary, and meningeal. Transcription profiling data of the macrophage for the three infections (Thuong et al, 2008) were integrated in the context of the host–pathogen network to elucidate the reaction activity of the three infections. There was wide heterogeneity in the three infection states; some of these differences are highlighted. Macrophage hyaluronan synthase and export were only active in the pulmonary infection. This is potentially interesting from a pharmaceutical viewpoint as hyaluronan has been implicated as a potential carbon source for extracellular M. tb (Hirayama et al, 2009). In addition, we detected metabolic activity differences in M. tb pathways that have been previously discussed as potential drug targets (Eoh et al, 2007; Boshoff et al, 2008). Polyprenyl metabolic reactions were only active in the latent state infection, while de novo synthesis of nicotinamide cofactors was only active in latent and meningeal M. tb infections. Host-pathogen modeling represents a novel approach for studying metabolic interactions during infection. iAB-AMØ-1410-Mt-661 is a more accurate platform for understanding the biology and pathophysiology of M. tb infection. Most importantly, genome-scale metabolic reconstructions can act as scaffolds for integrating high-throughput data. Particularly, in this study we were able to discern reaction activity differences between different infection types. Metabolic coupling of Mycobacterium tuberculosis to its host is foundational to its pathogenesis. Computational genome-scale metabolic models have shown utility in integrating -omic as well as physiologic data for systemic, mechanistic analysis of metabolism. To date, integrative analysis of host–pathogen interactions using in silico mass-balanced, genome-scale models has not been performed. We, therefore, constructed a cell-specific alveolar macrophage model, iAB-AMØ-1410, from the global human metabolic reconstruction, Recon 1. The model successfully predicted experimentally verified ATP and nitric oxide production rates in macrophages. This model was then integrated with an M. tuberculosis H37Rv model, iNJ661, to build an integrated host–pathogen genome-scale reconstruction, iAB-AMØ-1410-Mt-661. The integrated host–pathogen network enables simulation of the metabolic changes during infection. The resulting reaction activity and gene essentiality targets of the integrated model represent an altered infectious state. High-throughput data from infected macrophages were mapped onto the host–pathogen network and were able to describe three distinct pathological states. Integrated host–pathogen reconstructions thus form a foundation upon which understanding the biology and pathophysiology of infections can be developed.
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Janagama HK, Senthilkumar, Bannantine JP, Kugadas A, Jagtap P, Higgins L, Witthuhn B, Sreevatsan S. Iron-sparing response of Mycobacterium avium subsp. paratuberculosis is strain dependent. BMC Microbiol 2010; 10:268. [PMID: 20969756 PMCID: PMC2975660 DOI: 10.1186/1471-2180-10-268] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2010] [Accepted: 10/22/2010] [Indexed: 01/05/2023] Open
Abstract
Background Two genotypically and microbiologically distinct strains of Mycobacterium avium subsp. paratuberculosis (MAP) exist - S and C MAP strains that primarily infect sheep and cattle, respectively. Concentration of iron in the cultivation medium has been suggested as one contributing factor for the observed microbiologic differences. We recently demonstrated that S strains have defective iron storage systems, leading us to propose that these strains might experience iron toxicity when excess iron is provided in the medium. To test this hypothesis, we carried out transcriptional and proteomic profiling of these MAP strains under iron-replete or -deplete conditions. Results We first complemented M. smegmatisΔideR with IdeR of C MAP or that derived from S MAP and compared their transcription profiles using M. smegmatis mc2155 microarrays. In the presence of iron, sIdeR repressed expression of bfrA and MAP2073c, a ferritin domain containing protein suggesting that transcriptional control of iron storage may be defective in S strain. We next performed transcriptional and proteomic profiling of the two strain types of MAP under iron-deplete and -replete conditions. Under iron-replete conditions, C strain upregulated iron storage (BfrA), virulence associated (Esx-5 and antigen85 complex), and ribosomal proteins. In striking contrast, S strain downregulated these proteins under iron-replete conditions. iTRAQ (isobaric tag for relative and absolute quantitation) based protein quantitation resulted in the identification of four unannotated proteins. Two of these were upregulated by a C MAP strain in response to iron supplementation. The iron-sparing response to iron limitation was unique to the C strain as evidenced by repression of non-essential iron utilization enzymes (aconitase and succinate dehydrogenase) and upregulation of proteins of essential function (iron transport, [Fe-S] cluster biogenesis and cell division). Conclusions Taken together, our study revealed that C and S strains of MAP utilize divergent metabolic pathways to accommodate in vitro iron stress. The knowledge of the metabolic pathways these divergent responses play a role in are important to 1) advance our ability to culture the two different strains of MAP efficiently, 2) aid in diagnosis and control of Johne's disease, and 3) advance our understanding of MAP virulence.
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Affiliation(s)
- Harish K Janagama
- Department of Veterinary Population Medicine, University of Minnesota, Saint Paul, USA
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Brown AC, Eberl M, Crick DC, Jomaa H, Parish T. The nonmevalonate pathway of isoprenoid biosynthesis in Mycobacterium tuberculosis is essential and transcriptionally regulated by Dxs. J Bacteriol 2010; 192:2424-33. [PMID: 20172995 PMCID: PMC2863480 DOI: 10.1128/jb.01402-09] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2009] [Accepted: 02/11/2010] [Indexed: 12/30/2022] Open
Abstract
Mycobacterium tuberculosis synthesizes isoprenoids via the nonmevalonate or DOXP pathway. Previous work demonstrated that three enzymes in the pathway (Dxr, IspD, and IspF) are all required for growth in vitro. We demonstrate the essentiality of the key genes dxs1 and gcpE, confirming that the pathway is of central importance and that the second homolog of the synthase (dxs2) cannot compensate for the loss of dxs1. We looked at the effect of overexpression of Dxr, Dxs1, Dxs2, and GcpE on viability and on growth in M. tuberculosis. Overexpression of dxs1 or dxs2 was inhibitory to growth, whereas overexpression of dxr or gcpE was not. Toxicity is likely to be, at least partially, due to depletion of pyruvate from the cells. Overexpression of dxs1 or gcpE resulted in increased flux through the pathway, as measured by accumulation of the metabolite 4-hydroxy-3-methyl-but-2-enyl pyrophosphate. We identified the functional translational start site and promoter region for dxr and demonstrated that it is expressed as part of a polycistronic mRNA with gcpE and two other genes. Increased expression of this operon was seen in cells overexpressing Dxs1, indicating that transcriptional control is effected by the first enzyme of the pathway via an unknown regulator.
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Affiliation(s)
- Amanda C. Brown
- Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London E1 2AD, United Kingdom, Department of Infection, Immunity, and Biochemistry, School of Medicine, Cardiff University, Cardiff CF14 4XN, United Kingdom, Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado 80523, Institut für Klinische Immunologie und Transfusionsmedizin, Universitätsklinikum Giessen und Marburg, 35392 Giessen, Germany, Infectious Disease Research Institute, Seattle, Washington 98104
| | - Matthias Eberl
- Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London E1 2AD, United Kingdom, Department of Infection, Immunity, and Biochemistry, School of Medicine, Cardiff University, Cardiff CF14 4XN, United Kingdom, Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado 80523, Institut für Klinische Immunologie und Transfusionsmedizin, Universitätsklinikum Giessen und Marburg, 35392 Giessen, Germany, Infectious Disease Research Institute, Seattle, Washington 98104
| | - Dean C. Crick
- Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London E1 2AD, United Kingdom, Department of Infection, Immunity, and Biochemistry, School of Medicine, Cardiff University, Cardiff CF14 4XN, United Kingdom, Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado 80523, Institut für Klinische Immunologie und Transfusionsmedizin, Universitätsklinikum Giessen und Marburg, 35392 Giessen, Germany, Infectious Disease Research Institute, Seattle, Washington 98104
| | - Hassan Jomaa
- Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London E1 2AD, United Kingdom, Department of Infection, Immunity, and Biochemistry, School of Medicine, Cardiff University, Cardiff CF14 4XN, United Kingdom, Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado 80523, Institut für Klinische Immunologie und Transfusionsmedizin, Universitätsklinikum Giessen und Marburg, 35392 Giessen, Germany, Infectious Disease Research Institute, Seattle, Washington 98104
| | - Tanya Parish
- Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London E1 2AD, United Kingdom, Department of Infection, Immunity, and Biochemistry, School of Medicine, Cardiff University, Cardiff CF14 4XN, United Kingdom, Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado 80523, Institut für Klinische Immunologie und Transfusionsmedizin, Universitätsklinikum Giessen und Marburg, 35392 Giessen, Germany, Infectious Disease Research Institute, Seattle, Washington 98104
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García-Moreno D, Abellón-Ruiz J, García-Heras F, Murillo FJ, Padmanabhan S, Elías-Arnanz M. CdnL, a member of the large CarD-like family of bacterial proteins, is vital for Myxococcus xanthus and differs functionally from the global transcriptional regulator CarD. Nucleic Acids Res 2010; 38:4586-98. [PMID: 20371514 PMCID: PMC2919716 DOI: 10.1093/nar/gkq214] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
CarD, a global transcriptional regulator in Myxococcus xanthus, interacts with CarG via CarDNter, its N-terminal domain, and with DNA via a eukaryotic HMGA-type C-terminal domain. Genomic analysis reveals a large number of standalone proteins resembling CarDNter. These constitute, together with the RNA polymerase (RNAP) interacting domain, RID, of transcription–repair coupling factors, the CarD_TRCF protein family. We show that one such CarDNter-like protein, M. xanthus CdnL, cannot functionally substitute CarDNter (or vice versa) nor interact with CarG. Unlike CarD, CdnL is vital for growth, and lethality due to its absence is not rescued by homologs from various other bacteria. In mycobacteria, with no endogenous DksA, the function of the CdnL homolog mirrors that of Escherichia coli DksA. Our finding that CdnL, like DksA, is indispensable in M. xanthus implies that they are not functionally redundant. Cells are normal on CdnL overexpression, but divide aberrantly on CdnL depletion. CdnL localizes to the nucleoid, suggesting piggyback recruitment by factors such as RNAP, which we show interacts with CdnL, CarDNter and RID. Our study highlights a complex network of interactions involving these factors and RNAP, and points to a vital role for M. xanthus CdnL in an essential DNA transaction that affects cell division.
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Affiliation(s)
- Diana García-Moreno
- Departamento de Genética y Microbiología, Facultad de Biología, Universidad de Murcia, Murcia, Spain
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Eoh H, Narayanasamy P, Brown AC, Parish T, Brennan PJ, Crick DC. Expression and characterization of soluble 4-diphosphocytidyl-2-C-methyl-D-erythritol kinase from bacterial pathogens. ACTA ACUST UNITED AC 2010; 16:1230-9. [PMID: 20064433 DOI: 10.1016/j.chembiol.2009.10.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2009] [Revised: 10/09/2009] [Accepted: 10/21/2009] [Indexed: 11/17/2022]
Abstract
Many bacterial pathogens utilize the 2-C-methyl-D-erythritol 4-phosphate pathway for biosynthesizing isoprenoid precursors, a pathway that is vital for bacterial survival and absent from human cells, providing a potential source of drug targets. However, the characterization of 4-diphosphocytidyl-2-C-methyl-D-erythritol (CDP-ME) kinase (IspE) has been hindered due to a lack of enantiopure CDP-ME and difficulty in obtaining pure IspE. Here, enantiopure CDP-ME was chemically synthesized and recombinant IspE from bacterial pathogens were purified and characterized. Although gene disruption was not possible in Mycobacterium tuberculosis, IspE is essential in Mycobacterium smegmatis. The biochemical and kinetic characteristics of IspE provide the basis for development of a high throughput screen and structural characterization.
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Affiliation(s)
- Hyungjin Eoh
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
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Kalinowska-Tłuścik J, Miallau L, Gabrielsen M, Leonard GA, McSweeney SM, Hunter WN. A triclinic crystal form of Escherichia coli 4-diphosphocytidyl-2C-methyl-D-erythritol kinase and reassessment of the quaternary structure. Acta Crystallogr Sect F Struct Biol Cryst Commun 2010; 66:237-41. [PMID: 20208151 PMCID: PMC2833027 DOI: 10.1107/s1744309109054591] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2009] [Accepted: 12/18/2009] [Indexed: 11/10/2022]
Abstract
4-Diphosphocytidyl-2C-methyl-D-erythritol kinase (IspE; EC 2.7.1.148) contributes to the 1-deoxy-D-xylulose 5-phosphate or mevalonate-independent biosynthetic pathway that produces the isomers isopentenyl diphosphate and dimethylallyl diphosphate. These five-carbon compounds are the fundamental building blocks for the biosynthesis of isoprenoids. The mevalonate-independent pathway does not occur in humans, but is present and has been shown to be essential in many dangerous pathogens, i.e. Plasmodium species, which cause malaria, and gram-negative bacteria. Thus, the enzymes involved in this pathway have attracted attention as potential drug targets. IspE produces 4-diphosphosphocytidyl-2C-methyl-D-erythritol 2-phosphate by ATP-dependent phosphorylation of 4-diphosphocytidyl-2C-methyl-D-erythritol. A triclinic crystal structure of the Escherichia coli IspE-ADP complex with two molecules in the asymmetric unit was determined at 2 A resolution and compared with a monoclinic crystal form of a ternary complex of E. coli IspE also with two molecules in the asymmetric unit. The molecular packing is different in the two forms. In the asymmetric unit of the triclinic crystal form the substrate-binding sites of IspE are occluded by structural elements of the partner, suggesting that the ;triclinic dimer' is an artefact of the crystal lattice. The surface area of interaction in the triclinic form is almost double that observed in the monoclinic form, implying that the dimeric assembly in the monoclinic form may also be an artifact of crystallization.
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Affiliation(s)
- Justyna Kalinowska-Tłuścik
- Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland
- Faculty of Chemistry, Jagiellonian University, ul. R. Ingardena 3, 30-060 Krakow, Poland
| | - Linda Miallau
- Macromolecular Crystallography Group, European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble CEDEX 9, France
| | - Mads Gabrielsen
- Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland
| | - Gordon A. Leonard
- Macromolecular Crystallography Group, European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble CEDEX 9, France
| | - Sean M. McSweeney
- Macromolecular Crystallography Group, European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble CEDEX 9, France
| | - William N. Hunter
- Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland
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Narayanasamy P, Eoh H, Brennan PJ, Crick DC. Synthesis of 4-diphosphocytidyl-2-C-methyl-D-erythritol 2-phosphate and kinetic studies of Mycobacterium tuberculosis IspF. CHEMISTRY & BIOLOGY 2010; 17:117-22. [PMID: 20189102 PMCID: PMC2837070 DOI: 10.1016/j.chembiol.2010.01.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2009] [Revised: 01/22/2010] [Accepted: 01/29/2010] [Indexed: 10/19/2022]
Abstract
Many pathogenic bacteria utilize the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway for the biosynthesis of isopentenyl diphosphate and dimethylallyl diphosphate, two major building blocks of isoprenoid compounds. The fifth enzyme in the MEP pathway, 2-C-methyl-D-erythritol 2,4-cyclodiphosphate (ME-CPP) synthase (IspF), catalyzes the conversion of 4-diphosphocytidyl-2-C-methyl-D-erythritol 2-phosphate (CDP-ME2P) to ME-CPP with a corresponding release of cytidine 5-monophosphate (CMP). Because there is no ortholog of IspF in human cells, IspF is of interest as a potential drug target. However, study of IspF has been hindered by a lack of enantiopure CDP-ME2P. Herein, we report the first, to our knowledge, synthesis of enantiomerically pure CDP-ME2P from commercially available D-arabinose. Cloned, expressed, and purified M. tuberculosis IspF was able to utilize the synthetic CDP-ME2P as a substrate, a result confirmed by mass spectrometry. A convenient, sensitive, in vitro IspF assay was developed by coupling the CMP released during production of ME-CPP to mononucleotide kinase, which can be used for high throughput screening.
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Affiliation(s)
| | | | - Patrick J. Brennan
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences. Colorado State University, 1682 Campus Delivery, Fort Collins CO 80523-1682, USA
| | - Dean C. Crick
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences. Colorado State University, 1682 Campus Delivery, Fort Collins CO 80523-1682, USA
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Kaur D, Guerin ME, Skovierová H, Brennan PJ, Jackson M. Chapter 2: Biogenesis of the cell wall and other glycoconjugates of Mycobacterium tuberculosis. ADVANCES IN APPLIED MICROBIOLOGY 2009; 69:23-78. [PMID: 19729090 DOI: 10.1016/s0065-2164(09)69002-x] [Citation(s) in RCA: 148] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The re-emergence of tuberculosis in its present-day manifestations - single, multiple and extensive drug-resistant forms and as HIV-TB coinfections - has resulted in renewed research on fundamental questions such as the nature of the organism itself, Mycobacterium tuberculosis, the molecular basis of its pathogenesis, definition of the immunological response in animal models and humans, and development of new intervention strategies such as vaccines and drugs. Foremost among these developments has been the precise chemical definition of the complex and distinctive cell wall of M. tuberculosis, elucidation of the relevant pathways and underlying genetics responsible for the synthesis of the hallmark moieties of the tubercle bacillus such as the mycolic acid-arabinogalactan-peptidoglycan complex, the phthiocerol- and trehalose-containing effector lipids, the phosphatidylinositol-containing mannosides, lipomannosides and lipoarabinomannosides, major immunomodulators, and others. In this review, the laboratory personnel who have been the focal point of some to these developments review recent progress towards a comprehensive understanding of the basic physiology and functions of the cell wall of M. tuberculosis.
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Affiliation(s)
- Devinder Kaur
- Department of Microbiology, Immunology and Pathology, Mycobacteria Research Laboratories, Colorado State University, Fort Collins, CO 80523-1682, USA
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Obiol-Pardo C, Cordero A, Rubio-Martinez J, Imperial S. Homology modeling of Mycobacterium tuberculosis 2C-methyl-D-erythritol-4-phosphate cytidylyltransferase, the third enzyme in the MEP pathway for isoprenoid biosynthesis. J Mol Model 2009; 16:1061-73. [PMID: 19916033 DOI: 10.1007/s00894-009-0615-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2009] [Accepted: 10/06/2009] [Indexed: 02/02/2023]
Abstract
Tuberculosis is one of the leading infectious diseases in humans. Discovering new treatments for this disease is urgently required, especially in view of the emergence of multiple drug resistant organisms and to reduce the total duration of current treatments. The synthesis of isoprenoids in Mycobacterium tuberculosis has been reported as an interesting pathway to target, and particular attention has been focused on the methylerythritol phosphate (MEP) pathway comprising the early steps of isoprenoid biosynthesis. In this context we have studied the enzyme 2C-methyl-D-erythritol-4-phosphate cytidylyltransferase (CMS), the third enzyme in the MEP pathway, since the lack of a resolved structure of this protein in M. tuberculosis has seriously limited its use as a drug target. We performed homology modeling of M. tuberculosis CMS in order to provide a reliable model for use in structure-based drug design. After evaluating the quality of the model, we performed a thorough study of the catalytic site and the dimerization interface of the model, which suggested the most important sites (conserved and non-conserved) that could be useful for drug discovery and mutagenesis studies. We found that the metal coordination of CDP-methylerythritol in M. tuberculosis CMS differs substantially with respect to the Escherichia coli variant, consistent with the fact that the former is able to utilize several metal ions for catalysis. Moreover, we propose that electrostatic interactions could explain the higher affinity of the MEP substrate compared with the cytosine 5'-triphosphate substrate in the M. tuberculosis enzyme as reported previously.
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Affiliation(s)
- Cristian Obiol-Pardo
- Dept. de Química Física, Universitat de Barcelona, Intitut de Recerca en Química Teòrica i Computacional (IQTCUB), Martí i Franquès 1, 08028, Barcelona, Spain
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Vissa VD, Sakamuri RM, Li W, Brennan PJ. Defining mycobacteria: Shared and specific genome features for different lifestyles. Indian J Microbiol 2009; 49:11-47. [PMID: 23100749 DOI: 10.1007/s12088-009-0006-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2007] [Accepted: 08/16/2008] [Indexed: 11/28/2022] Open
Abstract
During the last decade, the combination of rapid whole genome sequencing capabilities, application of genetic and computational tools, and establishment of model systems for the study of a range of species for a spectrum of biological questions has enhanced our cumulative knowledge of mycobacteria in terms of their growth properties and requirements. The adaption of the corynebacterial surrogate system has simplified the study of cell wall biosynthetic machinery common to actinobacteria. Comparative genomics supported by experimentation reveals that superimposed on a common core of 'mycobacterial' gene set, pathogenic mycobacteria are endowed with multiple copies of several protein families that encode novel secretion and transport systems such as mce and esx; immunomodulators named PE/PPE proteins, and polyketide synthases for synthesis of complex lipids. The precise timing of expression, engagement and interactions involving one or more of these redundant proteins in their host environments likely play a role in the definition and differentiation of species and their disease phenotypes. Besides these, only a few species specific 'virulence' factors i.e., macromolecules have been discovered. Other subtleties may also arise from modifications of shared macromolecules. In contrast, to cope with the broad and changing growth conditions, their saprophytic relatives have larger genomes, in which the excess coding capacity is dedicated to transcriptional regulators, transporters for nutrients and toxic metabolites, biosynthesis of secondary metabolites and catabolic pathways. In this review, we present a sampling of the tools and techniques that are being implemented to tease apart aspects of physiology, phylogeny, ecology and pathology and illustrate the dominant genomic characteristics of representative species. The investigation of clinical isolates, natural disease states and discovery of new diagnostics, vaccines and drugs for existing and emerging mycobacterial diseases, particularly for multidrug resistant strains are the challenges in the coming decades.
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Affiliation(s)
- Varalakshmi D Vissa
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO-80523-1628 USA
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Yoya GK, Bedos-Belval F, Constant P, Duran H, Daffé M, Baltas M. Synthesis and evaluation of a novel series of pseudo-cinnamic derivatives as antituberculosis agents. Bioorg Med Chem Lett 2009; 19:341-3. [DOI: 10.1016/j.bmcl.2008.11.082] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2008] [Revised: 11/19/2008] [Accepted: 11/21/2008] [Indexed: 11/25/2022]
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Eoh H, Brennan PJ, Crick DC. The Mycobacterium tuberculosis MEP (2C-methyl-d-erythritol 4-phosphate) pathway as a new drug target. Tuberculosis (Edinb) 2008; 89:1-11. [PMID: 18793870 DOI: 10.1016/j.tube.2008.07.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2008] [Revised: 07/15/2008] [Accepted: 07/23/2008] [Indexed: 10/21/2022]
Abstract
Tuberculosis (TB) is still a major public health problem, compounded by the human immunodeficiency virus (HIV)-TB co-infection and recent emergence of multidrug-resistant (MDR) and extensively drug resistant (XDR)-TB. Novel anti-TB drugs are urgently required. In this context, the 2C-methyl-d-erythritol 4-phosphate (MEP) pathway of Mycobacterium tuberculosis has drawn attention; it is one of several pathways vital for M. tuberculosis viability and the human host lacks homologous enzymes. Thus, the MEP pathway promises bacterium-specific drug targets and the potential for identification of lead compounds unencumbered by target-based toxicity. Indeed, fosmidomycin is now known to inhibit the second step in the MEP pathway. This review describes the cardinal features of the main enzymes of the MEP pathway in M. tuberculosis and how these can be manipulated in high throughput screening campaigns in the search for new anti-infectives against TB.
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Affiliation(s)
- Hyungjin Eoh
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA.
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Mao J, Eoh H, He R, Wang Y, Wan B, Franzblau SG, Crick DC, Kozikowski AP. Structure-activity relationships of compounds targeting mycobacterium tuberculosis 1-deoxy-D-xylulose 5-phosphate synthase. Bioorg Med Chem Lett 2008; 18:5320-3. [PMID: 18783951 DOI: 10.1016/j.bmcl.2008.08.034] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2008] [Revised: 08/06/2008] [Accepted: 08/08/2008] [Indexed: 11/18/2022]
Abstract
We report on a target-based approach to identify possible Mycobacterium tuberculosis DXS inhibitors from the structure of a known transketolase inhibitor. A small focused library of analogs was assembled in order to begin elucidating some meaningful structure-activity relationships of 3-(4-chloro-phenyl)-5-benzyl-4H-pyrazolo[1,5-a]pyrimidin-7-one. Ultimately we found that 2-methyl-3-(4-fluorophenyl)-5-(4-methoxy-phenyl)-4H-pyrazolo[1,5-a]pyrimidin-7-one, although still weak, was able to inhibit M. tuberculosis DXS with an IC(50) of 10.6 microM.
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Affiliation(s)
- Jialin Mao
- Drug Discovery Program, Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, 833 South Wood Street, Chicago, IL 60612, USA
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Narayanasamy P, Eoh H, Crick DC. Chemoenzymatic synthesis of 4-diphosphocytidyl-2-C-methyl-D-erythritol: A substrate for IspE. Tetrahedron Lett 2008; 49:4461-4463. [PMID: 19088853 DOI: 10.1016/j.tetlet.2008.05.074] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Enantiomerically pure 2-C-methyl-D-erythritol 4-phosphate 1 (MEP) is synthesized from 1,2-O-isopropylidene-α-D-xylofuranose via facile benzylation in good yield. Subsequently, 1 is used for enzymatic synthesis of 4-diphosphocytidyl-2-C-methyl-D-erythritol 2 (CDP-ME) using 4-diphosphocytidyl-2-C-methyl-D-erythritol synthase (IspD). The chemoenzymatically synthesized 2 can be used as substrate for assay of IspE and for high throughput screening to identify IspE inhibitors.
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Affiliation(s)
- Prabagaran Narayanasamy
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences. Colorado State University, 1682 Campus Delivery, Fort Collins CO 80523-1682, USA
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Sgraja T, Alphey MS, Ghilagaber S, Marquez R, Robertson MN, Hemmings JL, Lauw S, Rohdich F, Bacher A, Eisenreich W, Illarionova V, Hunter WN. Characterization of Aquifex aeolicus 4-diphosphocytidyl-2C-methyl-d-erythritol kinase - ligand recognition in a template for antimicrobial drug discovery. FEBS J 2008; 275:2779-94. [PMID: 18422643 PMCID: PMC2655357 DOI: 10.1111/j.1742-4658.2008.06418.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
4-Diphosphocytidyl-2C-methyl-d-erythritol kinase (IspE) catalyses the ATP-dependent conversion of 4-diphosphocytidyl-2C-methyl-d-erythritol (CDPME) to 4-diphosphocytidyl-2C-methyl-d-erythritol 2-phosphate with the release of ADP. This reaction occurs in the non-mevalonate pathway of isoprenoid precursor biosynthesis and because it is essential in important microbial pathogens and absent from mammals it represents a potential target for anti-infective drugs. We set out to characterize the biochemical properties, determinants of molecular recognition and reactivity of IspE and report the cloning and purification of recombinant Aquifex aeolicus IspE (AaIspE), kinetic data, metal ion, temperature and pH dependence, crystallization and structure determination of the enzyme in complex with CDP, CDPME and ADP. In addition, 4-fluoro-3,5-dihydroxy-4-methylpent-1-enylphosphonic acid (compound 1) was designed to mimic a fragment of the substrate, a synthetic route to 1 was elucidated and the complex structure determined. Surprisingly, this ligand occupies the binding site for the ATP α-phosphate not the binding site for the methyl-d-erythritol moiety of CDPME. Gel filtration and analytical ultracentrifugation indicate that AaIspE is a monomer in solution. The enzyme displays the characteristic α/β galacto-homoserine-mevalonate-phosphomevalonate kinase fold, with the catalytic centre positioned in a deep cleft between the ATP- and CDPME-binding domains. Comparisons indicate a high degree of sequence conservation on the IspE active site across bacterial species, similarities in structure, specificity of substrate recognition and mechanism. The biochemical characterization, attainment of well-ordered and reproducible crystals and the models resulting from the analyses provide reagents and templates to support the structure-based design of broad-spectrum antimicrobial agents.
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Affiliation(s)
- Tanja Sgraja
- Division of Biological Chemistry and Drug Discovery, University of Dundee, UK
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Abstract
Enantiomerically pure 2-C-methyl-D-erythritol 2,4-cyclodiphosphate 1 (ME-CPP) is synthesized from 1,2-O-isopropylidene-α-D-xylofuranose with facile phosphorylation in good yield. Subsequently, the synthesized enantiomerically pure 1 can be used as a substrate in IspG assays to identify inhibitors that may be developed into antibacterial drug leads.
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Affiliation(s)
- Prabagaran Narayanasamy
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, 1682 Campus Delivery, Fort Collins, CO 80523-1682, USA
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