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ESCMID Online Lecture Library © by Author LONDON April, 2012 Are viruses the fourth domain of life or “Trucs?” or 1-2-3-4 © by author Didier Raoult Marseille - France ESCMID Online Lecture Library U [email protected] R 1 ‐Microbes (Sedillot,1878) Pasteur! ‐ Pasteurella multocida visible at the microscope © by author The agent of cholera fowlESCMID Online Lecture Library Prokaryotes – Eukaryotes (E.Chatton,1925) dichotomy based on the presence of a nucleus 2 There exist bacteria having a nucleus and histones. The definitions of Eukaryotes, Prokaryotes are false. © by author ESCMIDJA. Fuerst. Intracellular Online LectureCompartmentation Library in Planctomycetes. Ann. Rev Microbiol. 2005;59:299-328. © by author ESCMID Online Lecture Library Planctomycetes. Ann. Rev Microbiol. 2005;59:299-328. JA. Fuerst. Intracellular Compartmentation in Photographic credit: Gilbert Greub Ultrastructure of Criblamydia sequanensis (A), Parachlamydia acanthamoebae (B-C) and Waddlia chondrophila (D-F). We miss © by author nuclei on our plates! ESCMID Online Lecture Library Greub G, Bertelli C, Croxatto A, Raoult D. New Chlamydiales species question the origin of the nucleus. Confocal microscopy; 600x magnification. Elementary bodies of Parachlamydia acanthamoebae © by author ESCMID Online Lecture Library U Photographic credit: Gilbert Greub R 3 Archae C.Woese 1975 creates the ribosome based 3 domains NATURE|Vol 441|18 May 2006 ESSAY Time for a change © by author Prokaryote: gene-sequence comparisons show the tree of life consists of bacteria, eukarya and archaea. The use of the term ‘prokaryote’ fails to recognize that an idea about life’s origins has been proved wrong.ESCMID Online Lecture Library Norman R. Pace Archae - Archae is inappropriate name as it induces the opinion that this organism an ancestral and are extramophiles. - It produces most of the methane on the earth - In fact there are more archae cells in human body then Eukaryotic cells! - 10 % of the prokaryotes of the gut 500 nm Microscopie Electronique : Forme la plus proche des Methanobrevibacter Gram © by author Contrôle de la culture par microscopie optique: Les méthanogènes sont visualisés par la fluorescence de l'un de leurs co-enzymes uniques, le F420. (Culture de Methanobrevibacter marseillense à ESCMID Onlinepartir d’uneLecture selle). Library M.Drancourt © by author ESCMID Online Lecture Library There are new human species not found by 16S rDNA ? Virus definition An organism OR a biomolecule ? Lwoff – 1957 (Stanley vs Burnet) • One dimension < 200 nm Small specialized and • One type of nucleic acid mainly allotropic • Lack of enzymes generating energy • Strict intracellular character • Inability to undergo binary© fissionby author Lwoff A. The concept of virus. J Gen Microbiol. 1957;17:239-253. U ESCMID Online Lecture Library R Exceptions RNA or DNA Intracellular bacteria Binary fission Giant viruses Virophages Organelles “nanobacteria”and© byprion author Selfish DNA U ESCMID Online Lecture Library R What is a Rickettsia ? Gram negative bacterium Strictly intracellular (?) a1 subgroup of Proteobacteria by 16S rRNA sequence analysis Transmitted by arthropods:© by author ticks, fleas, lice, mites U ESCMID Online Lecture Library R FIG. 6. Electron photomicrograph of an ultrathin section of E. canis-infected DH82 cells demonstrating E. canis gp19 localization in a morula containing both reticulate and dense- cored ehrlichiae (A) and a corresponding ultrathin section containing uninfected DH82 cells (negative control) (B). Cells in both panels were reacted with mouse anti-gp19 antibody (1:10,000). Bar = 1 μm. © by authorMorula of Ehrlichia Jere W. McBride. Identification of a Glycosylated Ehrlichia canis 19-Kilodalton Major Immunoreactive Protein with a ESCMIDSpecies-Specific Serine-Rich Online Glycopeptide Lecture Epitope. Infect Immun. Library 2007; 75(1): 74–82 Viral factory looking like Morula © by author U ESCMID Online Lecture Library R © by author ESCMID Online Lecture Library U R © by author U ESCMIDBABL: intracellularOnline Lecture bacteria Library R © by author ESCMID Online Lecture Library H18 Amoeba for pathogen isolation © by author Legionella and Mimivirus Raoult D, et al. The 1.2-megabase genome sequence of Mimivirus. Science. 2004;306:1344-50. U La ScolaESCMID B, et al. A giant virusOnline in amoebae. Lecture Science;299:2033. Library R Mimivirus In 1992 Rowbotham working on relationships between amoebae and Legionella isolated a new Gram positive coccus in a cooling tower after a pneumonia outbreak in Bradford, England, using amoebae as a culture system. This was considered a LLAP (Legionella Like Amoebal Pathogen) with others © by author The LLAP collection was bring in Marseilles-France by Richard Birtles an English post-doc. U ESCMID Online Lecture Library R A GIANT VIRUS IN AMOEBAE Bernard La Scola,1 Stephane Audic,2 Catherine Robert,1Liang Jungang,1 Xavier de Lamballerie,3 Michel Drancourt, 1Richard Birtles,1 Jean-Michel Claverie,2* Didier Raoult1*SCIENCE VOL 299 28 MARCH 2003 © by author ESCMID Online Lecture Library U R Mimivirus – We show that it have a cycle in amoebae with a typical viral eclipse phase: ingestion disappearance © by author rapid increase in particles DNA + RNA! ESCMID Online Lecture Library U R Mimivirus It is as big as several bacteria and visible on gram staining © by author Mimivirus and Mimivirus and Mimivirus and Coxiella burnetiiESCMIDRickettsia Online conorii LectureTropheryma Library whipplei U R The 1.2-megabase genome sequence of Mimivirus Didier Raoult et al. Science. 2004 Nov 19;306(5700):1344-50. Map of the Mimivirus chromosome. The predicted protein coding sequences are shown on both strands and colored according to the function category of their matching COG. Genes with no COG match are shown in gray. Abbreviations for the COG functional categories are as follows: E, amino acid transport and metabolism; F, nucleotide transport and metabolism; J, translation; K, transcription; L, replication, recombination, and repair; M, cell wall/membrane biogenesis; N, cell motility; O, posttranslational modification, protein turnover, and chaperones; Q, secondary metabolites biosynthesis, transport, and catabolism; © by author R, general function prediction only; S, function unknown. Small red arrows indicate the location and orientation of tRNAs. The A+C excess profile is shown on the innermost circle, exhibiting a peak around position 380,000 (2)(fig.S1). ESCMID Online Lecture Library U R The Three Dimensional Structure of Mimivirus Klose T., Kuznetsov Y.G., Xiao C., Sun S., McPherson A., Rossmann M.G. CryoEM reconstruction of Mimivirus applying only fivefold symmetry averaging. (A–C) Surface- shaded rendering of cryoEM reconstruction of Mimivirus. (A) View onto the starfish-shaped feature associated vertex, (B) looking from one side, and(C) looking from the opposite side of the “starfish”- associated vertex. (D) The “starfish”- associated vertex was removed to show the internal nucleocapsid with its concave surface facing the special vertex. (E) Central slice of the reconstruction viewed from the side of the particle showing the concave© face ofby the nucleocapsidauthor and the low density space beneath the“starfish”-associated vertex. A perfectly icosahedral particle is outlined in gray to show the extension of the unique vertex. (F) Central slice of the reconstruction viewed along the fivefold axis from the starfish-shaped feature showing the enveloped nucleocapsid surrounded by a lower density space. The coloring is based on radial distance from the center of the virus. Gray is from 0 to 1,800 A, red from 1,800 to 2,100 A, and rainbow coloring from red to blue between 2,100 and 2,500 A. The scale bars inESCMID all panels Online represent 1,000Lecture A. Library (reproduced from [5]) Mimivirus as organism Mimivirus has a : – large genome (larger than many sequenced bacteria) – is as big as several bacteria – has plenty of RNA – many of its protein in the virion Virology: Gulliver among the Lilliputians. Koonin EV. Raoult D., et al. Science, 2004 Curr Biol 2005; 15(5): R167-R169. Raoult D., et al., Genome Res., 2003 Ogata H., et al., Science, 2001 © by author ESCMID Online Lecture Library Patients Respiratory Tested Positive infection Bronchial 110 2 (26) aspiration BAL 36 6 Others 50 0 Stools 846 0 1) M/47 / diabetic, pneumonia (fever, cough, dysprea) sampled on day 6, low WBC count© (2.300) by author 2) F/72 / diabetic, pneumonia (fever, cough, dysprea) sampled day 3, high risk (18.400) Both cured receiving cipofloxacine ESCMID OnlineFrom B.La Lecture Scola Library Clinical records Number LBA111 PathoMim Service EXT PN samples LB LB Age 47 72 Sex M F Habits Tabacco (30PA) Tabacco (15PA) Antecedents Diabetes II without dieting Respiratoiry infections, Diabetes II, HTA, Dyslipidemia, coronary Insufficiency Onset of the 6j 3j disease Functional signs Productive cough Productive cough Dyspnea Dyspnea Fever Fever physical Signs θ°= 38.7 θ° = 39,5 Asculai roaring, crackling right base tachypnea(26 cycles/min) Rx Systematized alveolar opacities of LID Biology GB : 2300 Asculai roaring, CRP : 330 Wheeze BK- © byGB : 18400author CRP : 283 VS : 57 BK- Treatment Levofloxacine 1fl/j (10j) Levofloxine (15j) O2 therapy EvolutionESCMID Improved clinical, biological Online and ImprovedLecture clinical, biological Library and radiological radiological © by author ESCMID Online Lecture Library (ø = 624 nm) PathoMim : negative staining © by author ESCMID Online Lecture Library PathoMim : Ruthunium red staining THE VIROPHAGE AS A UNIQUE PARASITE OF THE GIANT
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