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Bulterys MA, Wagner B, Redard-Jacot M, Suresh A, Pollock NR, Moreau E, Denkinger CM, Drain PK, Broger T. Point-Of-Care Urine LAM Tests for Tuberculosis Diagnosis: A Status Update. J Clin Med 2019; 9:E111. [PMID: 31906163 PMCID: PMC7020089 DOI: 10.3390/jcm9010111] [Citation(s) in RCA: 80] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Revised: 12/24/2019] [Accepted: 12/25/2019] [Indexed: 12/22/2022] Open
Abstract
Most diagnostic tests for tuberculosis (TB) rely on sputum samples, which are difficult to obtain and have low sensitivity in immunocompromised patients, patients with disseminated TB, and children, delaying treatment initiation. The World Health Organization (WHO) calls for the development of a rapid, biomarker-based, non-sputum test capable of detecting all forms of TB at the point-of-care to enable immediate treatment initiation. Lipoarabinomannan (LAM) is the only WHO-endorsed TB biomarker that can be detected in urine, an easily collected sample. This status update discusses the characteristics of LAM as a biomarker, describes the performance of first-generation urine LAM tests and reasons for slow uptake, and presents considerations for developing the next generation of more sensitive and impactful tests. Next-generation urine LAM tests have the potential to reach adult and pediatric patients regardless of HIV status or site of infection and facilitate global TB control. Implementation and scale-up of existing LAM tests and development of next-generation assays should be prioritized.
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Affiliation(s)
- Michelle A. Bulterys
- FIND, 1202 Geneva, Switzerland
- International Clinical Research Center, University of Washington, Seattle, WA 98105, USA
| | | | | | | | - Nira R. Pollock
- Department of Laboratory Medicine, Boston Children’s Hospital, Boston, MA 02115, USA
| | | | - Claudia M. Denkinger
- FIND, 1202 Geneva, Switzerland
- Division of Tropical Medicine, Center of Infectious Diseases, University of Heidelberg, 69120 Heidelberg, Germany
| | - Paul K. Drain
- International Clinical Research Center, University of Washington, Seattle, WA 98105, USA
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2
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Matsumoto M, Kubota T, Fujita S, Shiozaki K, Kishida S, Yamamoto A. Elucidation of the Interleukin 12 Production Mechanism during Intracellular Bacterial Infection in Amberjack, Seriola dumerili. Infect Immun 2019; 87:e00459-19. [PMID: 31501250 PMCID: PMC6803335 DOI: 10.1128/iai.00459-19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Accepted: 08/27/2019] [Indexed: 11/20/2022] Open
Abstract
Intracellular bacterial infections affect all vertebrates. Cultured fish are particularly vulnerable because no effective protection measures have been established since such infections emerged approximately 50 years ago. As in other vertebrates, the induction of cell-mediated immunity (CMI) plays an important role in protecting fish against infection. However, details of the mechanism of CMI induction in fish have not been clarified. In the present study, we focused on the production of interleukin 12 (IL-12), an important factor in CMI induction in fish. Using several different approaches, we investigated IL-12 regulation in amberjack (Seriola dumerili), the species most vulnerable to intracellular bacterial disease. The results of promoter assays and transcription factor gene expression analyses showed that the expression of interferon regulatory factor-1 (IRF-1) and activator protein-1 (AP-1) is necessary for IL-12 production. Phagocytosis of living cells (LCs) of Nocardia seriolae bacteria induced IL-12 production in neutrophils, accompanied by IRF-1 and AP-1 gene expression. Bacteria in which the exported repetitive protein (Erp)-like gene was deleted (Δerp-L) could not establish intracellular parasitism or induce IRF-1 and AP-1 expression or IL-12 production, despite being phagocytosed by neutrophils. These data suggest that IL-12 production is regulated by (i) two transcription factors, IRF-1 and AP-1, (ii) phagocytosis of LCs by neutrophils, and (iii) one or more cell components of LCs. Our results enhance the understanding of the immune response to intracellular bacterial infections in vertebrates and could facilitate the discovery of new agents to prevent intracellular bacterial disease.
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Affiliation(s)
- Megumi Matsumoto
- The United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima, Japan
| | - Taisei Kubota
- Faculty of Fisheries, Kagoshima University, Kagoshima, Japan
| | - Sinsuke Fujita
- Faculty of Fisheries, Kagoshima University, Kagoshima, Japan
| | - Kazuhiro Shiozaki
- The United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima, Japan
- Faculty of Fisheries, Kagoshima University, Kagoshima, Japan
| | - Shosei Kishida
- Faculty of Medicine, Kagoshima University, Kagoshima, Japan
| | - Atsushi Yamamoto
- The United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima, Japan
- Faculty of Fisheries, Kagoshima University, Kagoshima, Japan
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3
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Suthagar K, Jiao W, Munier-Lehmann H, Fairbanks AJ. Synthesis of sulfamide analogues of deoxthymidine monophosphate as potential inhibitors of mycobacterial cell wall biosynthesis. Carbohydr Res 2018; 457:32-40. [PMID: 29348046 DOI: 10.1016/j.carres.2018.01.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 01/08/2018] [Accepted: 01/08/2018] [Indexed: 11/26/2022]
Abstract
The recently discovered enzyme Mycobacterium tuberculosis thymidine monophosphate kinase (TMPKmt), which catalyses the phosphorylation of deoxythymidine monophosphate (dTMP) to give deoxythymidine diphosphate (dTDP), is indispensable for the growth and survival of M. tuberculosis as it plays an essential role in DNA synthesis. Inhibition of TMPKmt is an attractive avenue for the development of novel anti-tuberculosis agents. Based on the premise that sulfamide may be a suitable isostere of phosphate, deoxythymidine analogues comprising various substituted sulfamides at C5' were modelled in silico into the active site of TMPKmt (PDB accession code: 1N5K) using induced-fit docking methods. A selection of modelled compounds was synthesized, and their activity as inhibitors of TMPKmt was evaluated. Three compounds showed competitive inhibition of TMPKmt in the micromolar range (10-50 μM). Compounds were tested in vitro for anti-mycobacterial activity against M. smegmatis: three compounds showed weak anti-mycobacterial activity (MIC 250 μg/mL).
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Affiliation(s)
- Kajitha Suthagar
- Department of Chemistry, University of Canterbury, Private Bag 4800, Christchurch, 8140, New Zealand
| | - Wanting Jiao
- Department of Chemistry, University of Canterbury, Private Bag 4800, Christchurch, 8140, New Zealand; Ferrier Research Institute, Victoria University of Wellington, PO Box 600, Wellington, 6140, New Zealand
| | - Hélène Munier-Lehmann
- Institut Pasteur, Unité de Chimie et Biocatalyse, 28 rue du Dr Roux, 75724, Paris Cedex 15, France; CNRS UMR3523, 28 rue du Dr Roux, France
| | - Antony J Fairbanks
- Department of Chemistry, University of Canterbury, Private Bag 4800, Christchurch, 8140, New Zealand; Biomolecular Interaction Centre, University of Canterbury, Private Bag 4800, Christchurch, 8140, New Zealand.
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4
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Sadeghi-Khomami A, Forcada TJ, Wilson C, Sanders DAR, Thomas NR. The UDP-Galp mutase catalyzed isomerization: synthesis and evaluation of 1,4-anhydro-beta-D-galactopyranose and its [2.2.2] methylene homologue. Org Biomol Chem 2010; 8:1596-602. [PMID: 20237670 DOI: 10.1039/b917409e] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The synthesis of 1,4-anhydro-beta-D-galactopyranose (1,5-anhydro-alpha-D-galactofuranose), a proposed intermediate in the ring contraction isomerisation catalyzed by UDP-galactopyranose mutase, together with its [2.2.2] bicyclic methylene homologue, synthesised as a possible competitive inhibitor or alternative substrate, are reported. Neither compound was found to be an inhibitor or substrate for UDP-galactopyranose mutase from Klebsiella pneumoniae.
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Affiliation(s)
- Ali Sadeghi-Khomami
- School of Chemistry, Centre for Biomolecular Sciences, University of Nottingham, University Park, Nottingham, United Kingdom NG7 2RD
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Carlson EE, May JF, Kiessling LL. Chemical probes of UDP-galactopyranose mutase. ACTA ACUST UNITED AC 2006; 13:825-37. [PMID: 16931332 DOI: 10.1016/j.chembiol.2006.06.007] [Citation(s) in RCA: 112] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2006] [Revised: 06/05/2006] [Accepted: 06/06/2006] [Indexed: 12/26/2022]
Abstract
Many pathogenic prokaryotes and eukaryotes possess the machinery required to assemble galactofuranose (Galf)-containing glycoconjugates; these glycoconjugates can be critical for virulence or viability. Accordingly, compounds that block Galf incorporation may serve as therapeutic leads or as probes of the function of Galf-containing glycoconjugates. The enzyme UDP-galactopyranose mutase (UGM) is the only known generator of UDP-galactofuranose, the precursor to Galf residues. We previously employed a high-throughput fluorescence polarization assay to investigate the Klebsiella pneumoniae UGM. We demonstrate the generality of this assay by extending it to UGM from Mycobacterium tuberculosis. To identify factors influencing binding, we synthesized a directed library containing a 5-arylidene-2-thioxo-4-thiazolidinone core, a structure possessing features common to ligands for both homologs. Our studies offer a blueprint for identifying inhibitors of the growing family of UGM homologs and provide insight into UGM inhibition.
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Affiliation(s)
- Erin E Carlson
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
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7
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Cociorva OM, Lowary TL. Synthesis of oligosaccharides as potential inhibitors of mycobacterial arabinosyltransferases. Di- and trisaccharides containing C-5 modified arabinofuranosyl residues. Carbohydr Res 2004; 339:853-65. [PMID: 14980829 DOI: 10.1016/j.carres.2003.12.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2003] [Accepted: 12/16/2003] [Indexed: 11/17/2022]
Abstract
The synthesis of a panel of oligosaccharides containing C-5 arabinofuranosyl residues (9-20) is described. These compounds are of interest as potential inhibitors of the alpha-(1-->5)-arabinosyltransferase involved in the assembly of mycobacterial cell-wall arabinan. In the series of compounds prepared, the 5-OH group on the nonreducing residue(s) is replaced, independently, with an amino, azido, fluoro, or methoxy functionality. The synthesis of the target compounds involved the preparation of a series of C-5 modified arabinofuranosyl thioglycosides (24-26) and their subsequent coupling to the appropriate acceptor species (21-23). Deprotection of the glycosylation products afforded the azido, fluoro, or methoxy analogs directly. The amino derivatives were obtained in one additional step by reduction of the azido compounds.
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Affiliation(s)
- Oana M Cociorva
- Department of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, OH 43210, USA
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8
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Han J, Gadikota RR, McCarren PR, Lowary TL. Synthesis of octyl arabinofuranosides as substrates for mycobacterial arabinosyltransferases. Carbohydr Res 2003; 338:581-8. [PMID: 12644370 DOI: 10.1016/s0008-6215(02)00541-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A panel of octyl oligosaccharides comprised of arabinofuranose rings have been synthesized via efficient and readily scaleable routes. The key glycosylation reactions involved the coupling of octyl glycoside acceptors with the appropriate thioglycosides using N-iodosuccinimide and silver triflate activation. These syntheses were undertaken to provide substrates suitable for use in assays of mycobacterial arabinosyltransferases.
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Affiliation(s)
- Jeongseok Han
- Department of Chemistry, The Ohio State University, 100 West 18th Avenue, 43210, Columbus, OH, USA
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9
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Centrone CA, Lowary TL. Synthesis and antituberculosis activity of C-phosphonate analogues of decaprenolphosphoarabinose, a key intermediate in the biosynthesis of mycobacterial arabinogalactan and lipoarabinomannan. J Org Chem 2002; 67:8862-70. [PMID: 12467400 DOI: 10.1021/jo026247r] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The cell wall complex in mycobacteria, including the human pathogen Mycobacterium tuberculosis, is comprised in large part of two polysaccharides that contain a significant number of arabinofuranose residues. Both polysaccharides are assembled by a family of arabinosyltransferases that use decaprenolphosphoarabinose (3) as the donor species. In this paper, we describe the synthesis of a panel of C-phosphonate analogues of 3, which were designed to inhibit these arabinosyltransferases and thus block the biosynthesis of mycobacterial cell wall polysaccharides. A number of routes were explored for the preparation of the targets. The successful approach involved the synthesis of a protected C-phosphonate allyl ester 16, which was then coupled to an alkene via an olefin cross metathesis reaction. Subsequent reduction of the alkene with diimide and deprotection afforded the targets. Screening of these compounds in vitro against Mycobacterium tuberculosis revealed that one of the compounds, 15f, possessed antituberculosis activity, with an MIC value of 3.13 microg/mL.
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Affiliation(s)
- Charla A Centrone
- Department of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus 43210, USA
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10
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Pan YT, Carroll JD, Elbein AD. Trehalose-phosphate synthase of Mycobacterium tuberculosis. Cloning, expression and properties of the recombinant enzyme. EUROPEAN JOURNAL OF BIOCHEMISTRY 2002; 269:6091-100. [PMID: 12473104 DOI: 10.1046/j.1432-1033.2002.03327.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The trehalose-phosphate synthase (TPS) of Mycobacterium smegmatis was previously purified to apparent homogeneity and several peptides from the 58 kDa protein were sequenced. Based on that sequence information, the gene for TPS was identified in the Mycobacterium tuberculosis genome, and the gene was cloned and expressed in Escherichia coli with a (His)6 tag at the amino terminus. The TPS was expressed in good yield and as active enzyme, and was purified on a metal ion column to give a single band of approximately 58 kDa on SDS/PAGE. Approximately 1.3 mg of purified TPS were obtained from a 1-L culture of E. coli ( approximately 2.3 g cell paste). The purified recombinant enzyme showed a single band of approximately 58 kDa on SDS/PAGE, but a molecular mass of approximately 220 kDa by gel filtration, indicating that the active TPS is probably a tetrameric protein. Like the enzyme originally purified from M. smegmatis, the recombinant enzyme is an unusual glycosyltransferase as it can utilize any of the nucleoside diphosphate glucose derivatives as glucosyl donors, i.e. ADP-glucose, CDP-glucose, GDP-glucose, TDP-glucose and UDP-glucose, with ADP-glucose, GDP-glucose and UDP-glucose being the preferred substrates. These studies prove conclusively that the mycobacterial TPS is indeed responsible for catalyzing the synthesis of trehalose-P from any of the nucleoside diphosphate glucose derivatives. Although the original enzyme from M. smegmatis was greatly stimulated in its utilization of UDP-glucose by polyanions such as heparin, the recombinant enzyme was stimulated only modestly by heparin. The Km for UDP-glucose as the glucosyl donor was approximately 18 mm, and that for GDP-glucose was approximately 16 mm. The enzyme was specific for glucose-6-P as the glucosyl acceptor, and the Km for this substrate was approximately 7 mm when UDP-glucose was the glucosyl donor and approximately 4 mm with GDP-glucose. TPS did not show an absolute requirement for divalent cations, but activity was increased about twofold by 10 mm Mn2+. This recombinant system will be useful for obtaining sufficient amounts of protein for structural studies. TPS should be a valuable target site for chemotherapeutic intervention in tuberculosis.
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Affiliation(s)
- Y T Pan
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA
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11
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Khasnobis S, Escuyer VE, Chatterjee D. Emerging therapeutic targets in tuberculosis: post-genomic era. Expert Opin Ther Targets 2002; 6:21-40. [PMID: 11901479 DOI: 10.1517/14728222.6.1.21] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Every minute, somewhere in the world four people die from tuberculosis (TB), yet it has been nearly 40 years since a novel drug was introduced to treat this disease. The ever increasing number of TB cases together with the advent of multi-drug resistant (MDR) TB, has stimulated the search for novel anti-TB agents. An array of novel drug targets is provided by the mycobacterial cell wall, whose integrity is essential for bacterial viability. Over the years researchers have identified potential drug targets that are associated with the synthesis of various cell wall constituents. This classic approach, together with the unravelling of the Mycobacterium tuberculosis genome sequence, has placed TB drug research in an unprecedented position. An entire new set of genetic and bioinformatic tools for probing potential drug targets is now available. As therapies using first-line drugs like isoniazid (INH) or rifampin in combination with second-line drugs, like ethambutol (EMB) still continues, a number of substituted fluoroquinolones are being considered as the new generation of anti-TB drugs for their favourable pharmacokinetic profile and excellent oral bioavailability. In this review, the future of anti-TB drugs is discussed with reflection on the structure and biosynthesis of cell wall constituents that are potential drug targets. The importance and relevance of the M. tuberculosis genome sequence for the development of novel anti-TB drugs, have also been underscored.
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Affiliation(s)
- Shampa Khasnobis
- Department of Microbiology, Colorado State University, Fort Collins, CO 80523, USA
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12
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Ma Y, Stern RJ, Scherman MS, Vissa VD, Yan W, Jones VC, Zhang F, Franzblau SG, Lewis WH, McNeil MR. Drug targeting Mycobacterium tuberculosis cell wall synthesis: genetics of dTDP-rhamnose synthetic enzymes and development of a microtiter plate-based screen for inhibitors of conversion of dTDP-glucose to dTDP-rhamnose. Antimicrob Agents Chemother 2001; 45:1407-16. [PMID: 11302803 PMCID: PMC90481 DOI: 10.1128/aac.45.5.1407-1416.2001] [Citation(s) in RCA: 110] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An L-rhamnosyl residue plays an essential structural role in the cell wall of Mycobacterium tuberculosis. Therefore, the four enzymes (RmlA to RmlD) that form dTDP-rhamnose from dTTP and glucose-1-phosphate are important targets for the development of new tuberculosis therapeutics. M. tuberculosis genes encoding RmlA, RmlC, and RmlD have been identified and expressed in Escherichia coli. It is shown here that genes for only one isotype each of RmlA to RmlD are present in the M. tuberculosis genome. The gene for RmlB is Rv3464. Rv3264c was shown to encode ManB, not a second isotype of RmlA. Using recombinant RmlB, -C, and -D enzymes, a microtiter plate assay was developed to screen for inhibitors of the formation of dTDP-rhamnose. The three enzymes were incubated with dTDP-glucose and NADPH to form dTDP-rhamnose and NADP(+) with a concomitant decrease in optical density at 340 nm (OD(340)). Inhibitor candidates were monitored for their ability to lower the rate of OD(340) change. To test the robustness and practicality of the assay, a chemical library of 8,000 compounds was screened. Eleven inhibitors active at 10 microM were identified; four of these showed activities against whole M. tuberculosis cells, with MICs from 128 to 16 microg/ml. A rhodanine structural motif was present in three of the enzyme inhibitors, and two of these showed activity against whole M. tuberculosis cells. The enzyme assay was used to screen 60 Peruvian plant extracts known to inhibit the growth of M. tuberculosis in culture; two extracts were active inhibitors in the enzyme assay at concentrations of less than 2 microg/ml.
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Affiliation(s)
- Y Ma
- Department of Microbiology, Colorado State University, Fort Collins, Colorado 80523, USA
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13
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Abstract
Tuberculosis is a chronic infectious disease caused by several species of mycobacteria. Due to multi-drug resistant strains of mycobacteria and to a high prevalence of tuberculosis in patients who have acquired human immunodeficiency syndrome (AIDS), the number of patients infected with the disease is increasing worldwide. Thus there is an urgent need for new effective antimycobacterial agents to replace those currently in use. In this instance, the plant kingdom is undoubtedly a valuable source for new anti-tuberculosis agents. The present review article reports the findings from an extensive literature search of all plants that have been assessed for antimycobacterial/antitubercular activity over the past 20-30 years. An attempt has been made to summarize the information in order to highlight those promising plant species which are worthy of further investigation as leads for drug development. Over 350 plant species from a wide range of families and origins, containing various chemical classes of compounds, have been screened for such activity. A review of the relevant in vitro assays using different species of pathogenic and non-pathogenic mycobacteria is also included.
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Affiliation(s)
- S M Newton
- The School of Pharmacy, University of Bradford, West Yorkshire, UK
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Salman M, Brennan PJ, Lonsdale JT. Synthesis of mycolic acids of mycobacteria: an assessment of the cell-free system in light of the whole genome. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1437:325-32. [PMID: 10101266 DOI: 10.1016/s1388-1981(99)00026-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Mycolic acids are 70-90 carbon, alpha-alkyl, beta-hydroxy fatty acids constituting a major component of the cell envelope of Mycobacterium tuberculosis. The fact that the mycolic acid biosynthetic pathway is both essential in mycobacteria and the target for many first-line anti-TB drugs necessitates a detailed understanding of its biochemistry. A whole cell-free, but cell particulate- and membrane-containing enzyme preparation for mycolic acid biosynthesis was developed a few years ago and studied extensively. This system was shown to catalyze the synthesis of mature mycolic acids from [14C]acetate, but allows only minimal deposition into the cell wall proper. In the meantime the sequence of the entire genome of M. tuberculosis has been elucidated and its analysis using numerous protein sequence-based algorithms predicted cytoplasmic localization and a soluble, not a particulate, nature for the enzymes involved in the mycolic acid synthetic pathway. Accordingly, we re-assessed the 'cell-free' system for mycolic acid synthesis and concluded that it is probably due to the presence of unbroken cells, since viable cells were recovered from the cell wall preparation. The amount of whole cells depended upon the efficiency of the cell disruption method and conditions, and the amount of mycolic acid synthesized by the putative cell-free system correlated with the content of whole cells. Thus, accumulated results from the use of this 'cell-free' cell wall-based system should be re-evaluated in the light of these new data.
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Affiliation(s)
- M Salman
- SmithKline Beecham Pharmaceuticals, 1250 S. Collegeville Rd., PO Box 5089, Collegeville, PA 19403, USA.
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15
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Abstract
Structural analysis has been successfully implemented recently to obtain valuable information on the mycobacterial cell wall components, many of which have formed the basis for biosynthesis and functional studies towards developing better drugs and possible vaccines. The highly complex and well organized structure unique to mycobacteria, represents the best target for novel antimycobacterial agents. Until recently, our knowledge of the enzymes responsible for the biogenesis of the cell wall components was almost negligible. The pathways are now being elucidated in several laboratories. Highlights of this review include significant advances in the structure and biochemistry of the major cell wall components and potential targets for generation of new drugs.
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Affiliation(s)
- D Chatterjee
- Department of Microbiology, Colorado State University, Fort Collins, Colorado 80523, USA.
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