DOCSLIB.ORG

Metabolism in Mycobacterium Leprae, M. Tuberculosis and Other

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Metabolism in Mycobacterium Leprae, M. Tuberculosis and Other BnaA Mtthcal BidUnm (1988) Vol 44, No 3, pp 547-561 Metabolism in Mycobacterium leprae M. tuberculosis and Downloaded from https://academic.oup.com/bmb/article/44/3/547/283569 by guest on 28 September 2021 other pathogenic mycobacteria P R Wheeler C Ratledge Department of Biochemistry, Untvernty of Hull, Hull Pathogenic mycobacteria have complex lipoidal cell walls. Most of them secrete further lipids which appear as a layer around intracellular organisms. This lipoidal exterior may protect mycobacteria inside macrophages from attempts that those host cells make to kill them Such protection could be especially important in M leprae which unusually lacks catalase, an important 'self-defence' enzyme. Intracellular mycobacteria must obtain key nutrients from the host. The role of mycobactm and exochelm in acquiring iron, the carbon and nitrogen sources—including metabolic intermediates—used, and control of biosynthetic pathways are discussed. M. tuberculosis is capable of synthesismg all its macromolecules but M. leprae depends on the host for purines (precursors of nucleic acids), and maybe other intermediates Pathogenic mycobacteria grow slowly, and the possibilities that permeability of the envelope to nutrients, catabolic or anabolic (particularly DNA, RNA synthesis) reactions are limiting to growth are considered. Some characteristic activities may represent targets for antimycobactenal agents. Although it is a considerable over-simplification, it could be asserted that most mycobacteria are no more than Escherichia coli wrapped up in a fur coat. Metabolic processes in mycobacteria, for 548 TUBERCULOSIS AND LEPROSY the most part, are therefore the same, in broad outline as have been elucidated in the more amenable bacteria. Thus it is the few activities which are characteristically mycobacterial and the differ- ences between pathogenic mycobacteria and more amenable mi- crobes, that we discuss in this article. In contrast to workers using E. coli, those of us who have Downloaded from https://academic.oup.com/bmb/article/44/3/547/283569 by guest on 28 September 2021 investigated the metabolism of mycobacteria do so with the dual disadvantages of having no adequately worked-out system for genetic manipulation of the mycobacteria and having to deal with cultures which, at best, are much more slow-growing than E. coli. At worst, some mycobacteria grow only with extreme difficulty (e.g. M. lepraemurium, M. paratuberculosis) while M. leprae does not grow in culture at all. Researches into the metabolism of M. tuberculosis and M. leprae follow two different approaches. With M. tuberculosis, much rele- vant research can be carried out using saprophytic mycobacteria as model systems in the first instance and observations can then be extended to organisms, such as BCG or even M. avium, before carrying out key experiments with virulent strains of M. tuberculo- sis. In such work, the emphasis has usually been on identifying those unusual aspects of metabolism in mycobacteria particularly in relation to their capabilities as pathogens. With researches into M. leprae, the quest is for that quirk of metabolism which renders the organism incapable of growing in laboratory medium. It is therefore necessary with this organism to establish that each pathway of metabolism is present and functional for surely more than one must be defective to account for its inability to grow in axenic culture. Microbial biochemists who study mycobacteria do so with specific objectives in mind. Perhaps though the greatest, and as yet unsolved, problem is to explain why even metabolically competent mycobacteria grow so much more slowly than most other bacteria and why it is that even within the mycobacteria there is such a wide variation in growth rates. In this short review, we have concentrated on those aspects of mycobacterial metabolism which are either unique to mycobac- teria or which may help to throw some light on their outstanding problems. STRUCTURE To understand mycobacteria one must begin by an understanding of the basic cell structure as it is here, within the envelope of the METABOLISM IN PATHOGENIC MYCOBACTER1A 549 bacterium, that lies the greatest difference with all other bacteria. The mycobacterial cell envelope is not only thicker than others but it is uniquely lipophilic. It is from this external barrier that arise the principal characteristics of the organism: acid-fastness, aggre- gation of cells, resistance to many bactericidal agents including lytic enzymes produced by invaded host cells and possibly impen- Downloaded from https://academic.oup.com/bmb/article/44/3/547/283569 by guest on 28 September 2021 etrability of some nutrients and even antibiotics. Various models of the mycobacterial envelope have been pro- posed which attempt to show the orientation of the major lipid components which abound in the cell wall. The model shown in Figure 1 is based on that proposed by Minnikin1 but modified (see Draper P, In: Proceedings of the Indo-UK Symposium on Leprosy: JALMA, Agra. April 1986; p. 155) to allow for the Phthiocerol dimycocerosate Cord factor SulphoJipid Mycolic acid Arabinogalactan Peptidoglycan Plasma membrane Cytoplasm Fig. 1 Model of the mycobactenal cell envelope (membrane and wall). This is based on the model of Minnikin1 modified according to Draper's suggestion (sec text) and thus allows for the size and branched nature of the arabinogalactan estenfied with mycohc acids on its branches. The diagram shows two dimensions; the arabinogalactan and peptidoglycan form a network of branched chains in the third dimension. The topography of the wall is speculative; complex hpids are shown interacting with arabinogalactan-bound mycohc acid chains, though the nature of such interactions has not been shown experimentally. Acyl moieties of phthiocerol dimycocerosate and sulpholipid are drawn short and could be underlapping acyl moieties of mycohc acids Carbohydrate moieties in glycohpids are shown with hatched lines. 550 TUBERCULOSIS AND LEPROSY relative sizes of the arabinogalactan (Mr ~ 30 000) and mycolate (Air ~ 1200) moieties and the branched nature of the arabino- galactan in the cell wall. The envelope is composed of a phospho- lipid plasma membrane, which may contain some unusual phospho- lipids (phosphatidylinositol mannosides) not found outside mycobacteria, to which abuts the typical peptidoglycan backbone Downloaded from https://academic.oup.com/bmb/article/44/3/547/283569 by guest on 28 September 2021 of a Gram-positive bacterial cell.1 Beyond the peptidoglycan lies a branched polymer of arabinogalactan, (arasgal2),, which is linked to the peptidoglycan via a phosphodiester bridge. On to the arabinogalactan matrix are attached the long chain (C60-C86) fatty acids, termed mycolic acids, which may also be linked to sugars such as trehalose giving molecules originally termed 'cord factor' (6,6'-dimycolyltrehalose). Sulpholipids,2 also based on trehalose, occur as do long chain wax esters of phthiocerol dimycocerosates.1 Numerous other complex molecules have been isolated from the walls and some may be associated with viru- lence of the organism—though precise correlations have yet to be made—others are more certainly involved with the antigenic reactions of the mycobacteria. One such molecule apparently unique to M. leprae is a phenolic glycolipid based on the phthiocerol dimycocerosate molecule.3 Many of these mole- cules—cord factor, sulpholipids, phthiocerol esters—appear to be readily extractable from the cell wall and thus probably occur as discrete, free entities, maybe in outer layers outside the cell wall. Others form part of larger macromolecular structures; some of the mycobacterial lipids (e.g. Wax D) detected in ageing, autolysing cultures during early studies are now recognised as breakdown products of much larger molecules. Almost nothing is known about the biosynthesis of complex, mycobacterial lipids. Some intermediates in the biochemical pathways have been elucidated with a fair degree of certainty,1 but enzymes in the pathways have yet to be shown. In M. tuberculosis, a wall-associated polypeptide of glutamic acid occurs linked to the peptidoglycan backbone.4 As this may not occur in avirulent strains or in BCG, it may have some role in virulence—though how a somewhat inocuous polymer could act in this way is far from clear. The peptidoglycan of M. leprae also has an unusual feature; the L-alanine moiety of the peptido part of the molecule appears to be completely replaced by glycine5 though no metabolic or structural significance has been suggested as arising from this difference as, in essence, a CH3 group is being replaced by an H atom. METABOLISM IN PATHOGENIC MYCOBACTERIA 551 NUTRITION OF INTRACELLULAR MYCOBACTERIA The nutritional requirements of M. tuberculosis are quite simple as the organism grows, albeit slowly, on minimal culture media but does not grow appreciably quicker on more complex media. Thus, all cell components can be synthesised from a supply of organic Downloaded from https://academic.oup.com/bmb/article/44/3/547/283569 by guest on 28 September 2021 + carbon (glycerol, glucose, etc.), inorganic nitrogen (NH4 ) and 6 2+ 2 + 3 3 + the usual inorganic elements (Mg , SO4 ~, K , PO4 ", Fe and other trace elements). However, it is difficult to elucidate the requirements of M. leprae as this organism only grows inside specific hosts (e.g. man and the armadillo) and thus will have available to it a complex array of host-derived nutrients. Which ones it uses can only be guessed at, but more
Load more

Recommended publications
  • The Complete Genome Sequence of Mycobacterium Bovis
    The complete genome sequence of Mycobacterium bovis Thierry Garnier*, Karin Eiglmeier*, Jean-Christophe Camus*†, Nadine Medina*, Huma Mansoor‡, Melinda Pryor*†, Stephanie Duthoy*, Sophie Grondin*, Celine Lacroix*, Christel Monsempe*, Sylvie Simon*, Barbara Harris§, Rebecca Atkin§, Jon Doggett§, Rebecca Mayes§, Lisa Keating‡, Paul R. Wheeler‡, Julian Parkhill§, Bart G. Barrell§, Stewart T. Cole*, Stephen V. Gordon‡¶, and R. Glyn Hewinson‡ *Unite´deGe´ne´ tique Mole´culaire Bacte´rienne and †PT4 Annotation, Ge´nopole, Institut Pasteur, 28 Rue du Docteur Roux, 75724 Paris Cedex 15, France; ‡Tuberculosis Research Group, Veterinary Laboratories Agency Weybridge, Woodham Lane, New Haw, Addlestone, Surrey KT15 3NB, United Kingdom; and §The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SA, United Kingdom Edited by John J. Mekalanos, Harvard Medical School, Boston, MA, and approved March 19, 2003 (received for review January 24, 2003) Mycobacterium bovis is the causative agent of tuberculosis in a The disease is caused by M. bovis, a Gram-positive bacillus range of animal species and man, with worldwide annual losses to with zoonotic potential that is highly genetically related to agriculture of $3 billion. The human burden of tuberculosis caused Mycobacterium tuberculosis, the causative agent of human tu- by the bovine tubercle bacillus is still largely unknown. M. bovis berculosis (5, 6). Although the human and bovine tubercle bacilli was also the progenitor for the M. bovis bacillus Calmette–Gue´rin can be differentiated by host range, virulence and physiological vaccine strain, the most widely used human vaccine. Here we features the genetic basis for these differences is unknown. M. describe the 4,345,492-bp genome sequence of M.
    [Show full text]
  • The Approved List of Biological Agents Advisory Committee on Dangerous Pathogens Health and Safety Executive
    The Approved List of biological agents Advisory Committee on Dangerous Pathogens Health and Safety Executive © Crown copyright 2021 First published 2000 Second edition 2004 Third edition 2013 Fourth edition 2021 You may reuse this information (excluding logos) free of charge in any format or medium, under the terms of the Open Government Licence. To view the licence visit www.nationalarchives.gov.uk/doc/ open-government-licence/, write to the Information Policy Team, The National Archives, Kew, London TW9 4DU, or email [email protected]. Some images and illustrations may not be owned by the Crown so cannot be reproduced without permission of the copyright owner. Enquiries should be sent to [email protected]. The Control of Substances Hazardous to Health Regulations 2002 refer to an ‘approved classification of a biological agent’, which means the classification of that agent approved by the Health and Safety Executive (HSE). This list is approved by HSE for that purpose. This edition of the Approved List has effect from 12 July 2021. On that date the previous edition of the list approved by the Health and Safety Executive on the 1 July 2013 will cease to have effect. This list will be reviewed periodically, the next review is due in February 2022. The Advisory Committee on Dangerous Pathogens (ACDP) prepares the Approved List included in this publication. ACDP advises HSE, and Ministers for the Department of Health and Social Care and the Department for the Environment, Food & Rural Affairs and their counterparts under devolution in Scotland, Wales & Northern Ireland, as required, on all aspects of hazards and risks to workers and others from exposure to pathogens.
    [Show full text]
  • Mycobacterium Leprae a Nd Elevation Of
    Lepr. Rev. (1978) 49, 203-213 Absence of jj-Glucuron idase in Mycobacterium leprae and Elevation of the Enzyme in I nfected Tissues K. PRABHAKARAN, E. B. HARRIS AND W. F. KIRCHHEIMER U. S. Public Health Service Hospital. Carville. LA 70 721. USA ,8-Glucuronidase actlVlty was determined in mouse footpads infected with My cobacterium leprae. in the leprosy organisms separated from the liver and spleen of experimentally infected armadillos, and in the armadillo tissues. Enzyme assays in th� mouse footpads were initiated 1 week after inoculation with M. /eprae and continued at monthly intervals for 12 months. In the mouse footpads and in the armadillo tissues, M. leprae infection resulted in remarkable elevations of ,8- glucuronidase leveis. The leprosy bacilli seemed to be devoid of the enzyme. In its properties like pH optimum, reaction velocity and effect of inhibitors, the activity detected in M. leprae resembled the host tis sue enzyme rather than bacterial ,8- glucuronidase; and the activity was found to be superficially adsorbed on the bacilli. lt is well established that phagocytes are rich in lysosomal enzymes. Evidently, the increased ,8-g1ucuronidase of the infected tissues is not derived from the invading organisms, but from the differenttypes of phagocytic cells infiltratingthe tissues. Introduction j3-Glucuronidase is an important hydrolytic enzyme ubiquitously distributed in animal tissues and in tissue fluids. Phagocytic cells are especially rich in j3-g1ucuronidase. In the mammalian liver, the enzyme is largely associated with Iysosomes, and approximately one-third of the activity is distributed in the endoplasmic reticulum. The hydrolase is closely correlated with cellular pro­ liferation and tissue repair; high leveis of the enzyme are found in the reproductive and endocrine organs and in tumours.
    [Show full text]
  • Mycobacterium Avium Subsp
    University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Veterinary and Biomedical Sciences, Papers in Veterinary and Biomedical Science Department of July 2001 Mycobacterium avium subsp. paratuberculosis in Veterinary Medicine N. Beth Harris University of Nebraska - Lincoln Raul G. Barletta University of Nebraska - Lincoln, [email protected] Follow this and additional works at: https://digitalcommons.unl.edu/vetscipapers Part of the Veterinary Medicine Commons Harris, N. Beth and Barletta, Raul G., "Mycobacterium avium subsp. paratuberculosis in Veterinary Medicine" (2001). Papers in Veterinary and Biomedical Science. 5. https://digitalcommons.unl.edu/vetscipapers/5 This Article is brought to you for free and open access by the Veterinary and Biomedical Sciences, Department of at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Papers in Veterinary and Biomedical Science by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. CLINICAL MICROBIOLOGY REVIEWS, July 2001, p. 489–512 Vol. 14, No. 3 0893-8512/01/$04.00ϩ0 DOI: 10.1128/CMR.14.3.489–512.2001 Copyright © 2001, American Society for Microbiology. All Rights Reserved. Mycobacterium avium subsp. paratuberculosis in Veterinary Medicine N. BETH HARRIS AND RAU´ L G. BARLETTA* Department of Veterinary and Biomedical Sciences, University of Nebraska—Lincoln, Lincoln, Nebraska 68583-0905 INTRODUCTION .......................................................................................................................................................489
    [Show full text]
  • Genomics Insights Into the Biology and Evolution of Leprosy Bacilli
    The International Textbook of Leprosy Part II Section 8 Chapter 8.2 Genomics Insights Into the Biology and Evolution of Leprosy Bacilli Pushpendra Singh Department of Microbiology and Biotechnology Centre, The Maharaja Sayajirao University of Baroda JoAnn Tufariello Department of Microbiology and Immunology, Albert Einstein College of Medicine Center for Microbial Pathogenesis, Institute for Biomedical Sciences, Georgia State University Alice R Wattam Biocomplexity Institute, Virginia Tech University Thomas P Gillis Effect: hope Department of Microbiology, Immunology and Parasitology, Louisiana State University School of Medicine William R Jacobs Jr Department of Microbiology and Immunology, Albert Einstein College of Medicine The International Textbook of Leprosy Genomics Insights Introduction GENERAL INTRODUCTION Leprosy is a chronic granulomatous disease that affects the peripheral nerves, skin, and eyes. It was strongly believed to be a hereditary disease until 1873, when a young Norwegian physician, Gerhard Armauer Hansen, demonstrated the causative bacterium of the disease. The pathogen, known as Mycobacterium leprae, has since defied all efforts to cultivate it in any artificial medi- um, thereby limiting traditional microbiological investigations. The availability of a very effective multi-drug therapy (MDT; see Chapter 2.6; Chapter 5.2) for over three decades has drastically reduced the prevalence of the disease; however, it has also facilitated the notion held by the general public and health policymakers that it is a disease of the past. This notion is clearly not the case, as new case detection rates of leprosy have stubbornly remained at or near 200,000 cases annually over the past decade (1). The persistent rate of new cases indicates that transmis- sion has not been completely interrupted by MDT and that a fuller understanding of transmis- sion (see Chapter 1.2) is required to fashion strategies aimed at reaching zero transmission of M.
    [Show full text]
  • Antigen-Coated Latex Particles As a Model System for Probing Monocyte Responses in Leprosy RUMINA S
    INFECrION AND IMMUNITY, Sept. 1993, p. 3724-3729 Vol. 61, No. 9 0019-9567/93/093724-06$02.00/0 Copyright C 1993, American Society for Microbiology Antigen-Coated Latex Particles as a Model System for Probing Monocyte Responses in Leprosy RUMINA S. HASAN,1* HAZEL M. DOCKRELL,2 SARWAT JAMIL,1 THOMAS J. CHIANG,3 AND RABIA HUSSAIN1 Department ofMicrobiology, Aga Khan University, Stadium Road,1 and Marie Adelaide Leprosy Centre, Mariam Manzil,3 Karachi 5, Pakistan, and Department of Clinical Sciences, London School ofHygiene and Tropical Medicine, London WCJE 7HT, United Kingdom2 Received 2 November 1992/Returned for modification 2 February 1993/Accepted 21 June 1993 To study responses to Mycobacterium leprae antigens, we developed an in vitro model system in which latex particles coated with M. keprae sonic extract (MLSON) antigen were presented to monocytes. Uptake and oxidative response as measured by superoxide production to these antigens were investigated. Phagocytosis of MLSON-coated particles was greater than that of control particles in monocytes from both leprosy patients and controls from leprosy-endemic areas; uptake of MLSON-coated particles was higher in monocytes from lepromatous leprosy patients than in cells from tuberculoid leprosy patients and controls. In both patients and controls, uptake of latex particles coated with leprosy antigens triggered very little reduction of nitroblue tetrazolium although the cells were capable of mounting a respiratory burst. Antigen-coated latex particles can therefore be used as a tool to investigate monocyte responses to M. leprae and individual recombinant antigens. The monocyte/macrophage is a central cell in the immune MATERIALS AND METHODS response to mycobacteria.
    [Show full text]
  • Journal of Clinical Microbiology
    JOURNAL OF CLINICAL MICROBIOLOGY Volume 45 June 2007 No. 6 BACTERIOLOGY Acute Postoperative Endophthalmitis Caused by C. Chiquet, A. Pechinot, C. 1673–1678 Staphylococcus lugdunensis Creuzot-Garcher, Y. Benito, J. Croize, S. Boisset, J. P. Romanet, G. Lina, and F. Vandenesch for the French Institutional Endophthalmitis Study Group Association of the Pneumococcal Pilus with Certain Alan Basset, Krzysztof Trzcinski, 1684–1689 Capsular Serotypes but Not with Increased Virulence Christina Hermos, Katherine L. O’Brien, Raymond Reid, Mathuram Santosham, Alexander J. McAdam, Marc Lipsitch, and Richard Malley Phenotypic Characterization of Clonal and Nonclonal Pholawat Tingpej, Lucas Smith, 1697–1704 Pseudomonas aeruginosa Strains Isolated from Lungs of Barbara Rose, Hua Zhu, Tim Adults with Cystic Fibrosis Conibear, Khaled Al Nassafi, Jim Manos, Mark Elkins, Peter Bye, Mark Willcox, Scott Bell, Claire Wainwright, and Colin Harbour Evaluation of the Novel Helicobacter pylori ClariRes Real- Christian Lottspeich, Andrea 1718–1722 Time PCR Assay for Detection and Clarithromycin Schwarzer, Klaus Panthel, Sibylle Susceptibility Testing of H. pylori in Stool Specimens from Koletzko, and Holger Ru¨ssmann Symptomatic Children Peptoniphilus gorbachii sp. nov., Peptoniphilus olsenii sp. nov., Yuli Song, Chengxu Liu, and 1746–1752 and Anaerococcus murdochii sp. nov. Isolated from Clinical Sydney M. Finegold Specimens of Human Origin Genetic and Antigenic Analysis of Invasive Serogroup Y Raymond S. W. Tsang, Averil M. 1753–1758 Neisseria meningitidis Isolates Collected from 1999 to 2003 Henderson, Marissa L. Cameron, in Canada Shaun D. Tyler, Shari Tyson, Dennis K. S. Law, Jan Stoltz, and Wendell D. Zollinger Genetic Diversity in a Bacillus anthracis Historical Collection David Sue, Chung K.
    [Show full text]
  • Deoxyribonucleic Acid Relatedness Among Mycobacterium Leprae, Mycobacterium Lepraernuriurn, and Selected Bacteria by Dot Blot An
    INTERNATIONAL JOURNAL OF SYSTEMATIC BACTERIOLOGY, OCt. 1984, p. 371-375 Vol. 34, No. 4 OO20-7713/84/O40371-05$02.OO/O Copyright 0 1984, International Union of Microbiological Societies Deoxyribonucleic Acid Relatedness Among Mycobacterium leprae, Mycobacterium lepraernuriurn, and Selected Bacteria by Dot Blot and Spectrophotometric Deoxyribonucleic Acid Hybridization Assays R. S. ATHWAL, S. S. DEO, AND T. IMAEDA* Department of Microbiology, UMDNJ-New Jersey Medical School, Newark, New Jersey 07103 Deoxyribonucleic acid relatedness between Mycobacterium leprae or Mycobacterium lepraemurium and other selected bacteria was studied by both dot blot and spectrophotometric deoxyribonucleic acid hybridization assays. The results obtained by the two methods were similar, except for the relatedness values between M. leprae and two corynebacterial strains. Among the mycobacterial species examined, acid-fast organisms isolated from armadillos and a mangabey monkey with leprosy-like disease showed 100% relatedness with M. leprae grown experimentally in armadillos, suggesting their common origin. In this study we demonstrate the usefulness of the dot blot hybridization technique as a screening method for mycobacterial taxonomy. The deoxyribonucleic acids (DNAs) of Mycobacterium tional Hansen's Disease Center. The acid-fast organism leprae and Mycobacterium lepraemurium were analyzed listed as M. leprae (Mangabey monkey) was isolated from kinetically to determine their genome sizes, base ratios, and spleen tissue of a mangabey monkey with leprosy-like dis- genetic relatedness to certain corynebacteria, mycobacteria, ease, which was supplied by W. M. Meyers, Armed Forces and nocardiae (5, 6). M. leprae grown in armadillos was Institute of Pathology (8). M. lepraemurium was isolated found to be a unique organism among the Corynebacterium- from mesenteric lymph nodes of mice infected with M.
    [Show full text]
  • Mycobacterium Bovis BCG but Not Mycobacterium Leprae Induces TNF
    Mem Inst Oswaldo Cruz, Rio de Janeiro, Vol. 96(7): 973-978, October 2001 973 Mycobacterium bovis BCG but not Mycobacterium leprae Induces TNF-α Secretion in Human Monocytic THP-1 Cells Martha M Oliveira, Rosane Charlab*, Maria Cristina V Pessolani/+ Laboratório de Hanseníase, Instituto Oswaldo Cruz-Fiocruz, Av. Brasil 4365, 21045-900 Rio de Janeiro, RJ, Brasil *Centro Brasileiro de Pesquisas Físicas, CNPq, Rio de Janeiro, RJ, Brasil In this study, we compared the level of TNF-α secretion induced in monocytic THP-1 cells after phagocytosis of Mycobacterium leprae, the causative agent of leprosy, and M. bovis BCG, an attenu- ated strain used as a vaccine against leprosy and tuberculosis. The presence of M. leprae and BCG was observed in more than 80% of the cells after 24 h of exposure. However, BCG but not M. leprae was able to induce TNF-α secretion in these cells. Moreover, THP-1 cells treated simultaneously with BCG and M. leprae secreted lower levels of TNF-α compared to cells incubated with BCG alone. M. leprae was able, however, to induce TNF-α secretion both in blood-derived monocytes as well as in THP-1 cells pretreated with phorbol myristate acetate. The inclusion of streptomycin in our cultures, together with the fact that the use of both gamma-irradiated M. leprae and heat-killed BCG gave similar results, indicate that the differences observed were not due to differences in viability but in intrinsic properties between M. leprae and BCG. These data suggest that the capacity of M. leprae to induce TNF-α is dependent on the stage of cell maturation and emphasize the potential of this model to explore differ- ences in the effects triggered by vaccine strain versus pathogenic species of mycobacteria on the host cell physiology and metabolism.
    [Show full text]
  • Standard Operating Procedure◄
    ►Standard Operating Procedure◄ Section: Laboratory Version: FINAL Initials: AD Title: 2.0 Testing Algorithm Revision Date: 20 Oct 2011 1. Definitions 1.1 SOP: Standard Operating Procedure 1.2 CRF: Case Report Form 2. Purpose / Background 2.1. The purpose of this SOP is to provide guidance for the processing, testing and storage of all PERCH study specimens. 3. Scope / Applicability 3.1. This SOP applies to all laboratory personnel involved in the processing of laboratory specimens. 4. Prerequisites / Supplies Needed 4.1. See test specific SOPs for supplies needed. 5. Roles / Responsibilities [Site specific, as needed] 6. Procedural Steps 6.1 Accepting/Rejecting Specimens: Staff who receive specimens in the laboratory are responsible, to the best of their ability, for ensuring that specimens have been stored and transported under the conditions specified in Appendix 1, Specimen Transport and Storage Conditions. Specimens will only be rejected for processing for the following reasons: (a) specimen is unlabeled (b) specimen ID does not match the requisition form (c) blood is hemolyzed, or anticoagulated specimens contain clots (d) specimen container is leaking. 6.2 Process all study specimens according to the flow charts and specimen preparation tables below. Any departure from the flow charts listed below (e.g. instances of insufficient volume) should be documented as part of the laboratory’s quality management process. For specific processing instructions, please refer to the relevant specimen processing SOP. SOP ID# 2.0 Testing Algorithm version : FINAL Page 2 of 30 *NB As an alternative, all EDTA blood from cases 6.1a can be collected into one tube.
    [Show full text]
  • The Impact of Chlorine and Chloramine on the Detection and Quantification of Legionella Pneumophila and Mycobacterium Spp
    The impact of chlorine and chloramine on the detection and quantification of Legionella pneumophila and Mycobacterium spp. Maura J. Donohue Ph.D. Office of Research and Development Center of Environmental Response and Emergency Response (CESER): Water Infrastructure Division (WID) Small Systems Webinar January 28, 2020 Disclaimer: The views expressed in this presentation are those of the author and do not necessarily reflect the views or policies of the U.S. Environmental Protection Agency. A Tale of Two Bacterium… Legionellaceae Mycobacteriaceae • Legionella (Genus) • Mycobacterium (Genus) • Gram negative bacteria • Nontuberculous Mycobacterium (NTM) (Gammaproteobacteria) • M. avium-intracellulare complex (MAC) • Flagella rod (2-20 µm) • Slow grower (3 to 10 days) • Gram positive bacteria • Majority of species will grow in free-living • Rod shape(1-10 µm) amoebae • Non-motile, spore-forming, aerobic • Aerobic, L-cysteine and iron salts are required • Rapid to Slow grower (1 week to 8 weeks) for in vitro growth, pH: 6.8 to 7, T: 25 to 43 °C • ~156 species • ~65 species • Some species capable of causing disease • Pathogenic or potentially pathogenic for human 3 NTM from Environmental Microorganism to Opportunistic Opponent Genus 156 Species Disease NTM =Nontuberculous Mycobacteria MAC = M. avium Complex Mycobacterium Mycobacterium duvalii Mycobacterium litorale Mycobacterium pulveris Clinically Relevant Species Mycobacterium abscessus Mycobacterium elephantis Mycobacterium llatzerense. Mycobacterium pyrenivorans, Mycobacterium africanum Mycobacterium europaeum Mycobacterium madagascariense Mycobacterium rhodesiae Mycobacterium agri Mycobacterium fallax Mycobacterium mageritense, Mycobacterium riyadhense Mycobacterium aichiense Mycobacterium farcinogenes Mycobacterium malmoense Mycobacterium rufum M. avium, M. intracellulare, Mycobacterium algericum Mycobacterium flavescens Mycobacterium mantenii Mycobacterium rutilum Mycobacterium alsense Mycobacterium florentinum. Mycobacterium marinum Mycobacterium salmoniphilum ( M. fortuitum, M.
    [Show full text]
  • The Distribution and Origins of Ancient Leprosy
    Chapter 2 The Distribution and Origins of Ancient Leprosy Helen D. Donoghue,D. Donoghue, G. MichaelG. Michael Taylor, Tom A. Mendum,A. Mendum, GrahamGraham R. Stewart,R. Stewart, Leen Rigouts,Leen Rigouts, Oona Y-C. Lee,Y-C. Lee, HoudiniHoudini H.T. Wu,H.T. Wu, Gurdyal S. Besra andGurdyal David S. BesraE. Minnikin and David E. Minnikin Additional information is available at the end of the chapter http://dx.doi.org/10.5772/intechopen.75260 Abstract Human leprosy is primarily caused by Mycobacterium leprae, but also by the related ‘M. lepromatosis’. Ancient leprosy can be recognised in archaeological materials by the paleopathology associated with multi-bacillary or lepromatous forms of the disease. Whole M. leprae genomes have been obtained from human skeletons, and diagnostic aDNA frag- ments have been recovered. The derived M. leprae phylogenies, based on single nucleotide polymorphisms, mirror past human migrations, as M. leprae is usually an obligate pathogen. The detection of M. leprae in historical leprosy cases is assisted by the hydrophobic M. leprae cell envelope, which is composed of unusual lipids that can be used as specifc biomarkers. Lipid biomarkers are more stable than aDNA and can be detected directly without amplif- cation. Indigenous human leprosy is extinct in Western Europe, but recently, both M. leprae and ‘M. lepromatosis’ were found in British red squirrels. Leprosy may also be found in nine- banded armadillos (Dasypus novemcinctus) where it can cause a zoonotic human infection. Certain leprosy-like diseases, caused by uncultivable species in cats, for example, may be related to M. leprae. The closest extant relatives of leprosy bacilli are probably members of the M.
    [Show full text]