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Viruses of Microbial Extremophiles Who, What, When, Where? And How!

Viruses of Microbial Extremophiles Who, What, When, Where? And How!. NASA – NSF – TSU Fourth Annual RESEARCH SYMPOSIUM “Developing Student Research”. Rhonda L. Lane*, Tennessee State University E. Myles Lewis, Tennessee state University Todd Gary, Tennessee State University

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Viruses of Microbial Extremophiles Who, What, When, Where? And How!

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  1. Viruses of MicrobialExtremophilesWho, What, When, Where?And How! NASA – NSF – TSU Fourth Annual RESEARCH SYMPOSIUM “Developing Student Research” Rhonda L. Lane*, Tennessee State University E. Myles Lewis, Tennessee state University Todd Gary, Tennessee State University Kenneth Stedman, Portland State University

  2. Viruses • obligate intracellular parasites • require hosts for replication • ALL ORGANISMS probably have viruses or • virus like particles!!

  3. Bacteriophage from the greek phagein, meaning "to eat“ Eaters or destroyers of bacteria First described in 1915

  4. Abundance “In 1 drop of seawater 50 million phages per ml!” (Curtis Suttle, University of British Columbia, Vancouver) “They are nature’s most successful experiment. They outnumber all other life forms combined.” (Marisa Pedulla, University of Pittsburg) Estimates are 1031 phages on Earth (10 for every bacterium) (1998 Whitman, Coleman & Wiche published est. number of bacteria at 1030) “If phages were the size of a beetle, they would cover the earth and be many miles deep.” (Marisa Pedulla, University of Pittsburg)

  5. Bacteriophage

  6. Lytic and Lysogenic Lifecycles Lysogenic lifecycle is probably the more evolved.

  7. WHAT ARE THEY? Microbial Extremophiles

  8. Bacteria vs Archae Bacteria • Evolved separately • Peptidoglycan in cell wall • Tolerance for Extreme Environments

  9. Microbial Extremophiles • Extreme Ranges of pH • Acidophiles: (pH < 6.0), minimum at - 0.3 • Neutrophiles: (pH 6.5 - 8.0) • Alkalophiles: (pH > 8.0), maximum at 12-13 • Extreme Ranges of Salinity • Freshwater: (< 1 %) • Marine: (~ 3 %) • Halophiles: (~ 10-30 %)

  10. Viruses of Archae Halophiles and Methanogens Family - Myoviridae and Siphoviridae Classified by morphology & sequence analysis • head and tail viruses • ds linear DNA genome • temperate and lytic propagation

  11. Halophage Methanophage Typical of the 12 best studied viruses from Methanogens

  12. Morphology according to ICTV Most Methanophage and Halophages are either Myoviridae or Siphoviridae

  13. Microbial Extremophiles • Extreme Ranges of Temperature for Growth • Psychrophiles: (–4 to +10 oC) • Psychrotolerants: (+ 10 to +20 oC) • Mesophiles: (+20 to +50 oC) • Moderate Thermophiles: (+50 to +70 oC) • Thermophiles: (+70 to +90 oC) • Hyperthermophiles: (+90 to >+125 oC)

  14. Thermophiles 1969- microbes discovered in hot springs of Yellowstone (80° C)

  15. Thermophiles 1977- life revealed near hydrothermal vents (115° C) First chemotrophic community discovered

  16. WHEN WERE THEY? What’s so special about thermophilic Archae?

  17. They are so special because of When! • Thermophilic Archaea • Similar to Eukarya • Evolution • Archaea are everywhere • Establish molecular genetics • in vivo analysis • Expression You are here!

  18. Archae RNAP and transcription factors very similar to Eukaryotic

  19. WHERE ARE THEY?Model Host Organism Sulfolobus solfataricus

  20. Sulfolobus solfataricus • Extremely thermophilic archaeon • 80°C, pH+ 3.0 optimum • Easy to grow • Heterotrophic aerobe • Can form lawn • UVinduced phage • Completely sequenced • 3 Mbp genome S.solfataricus, strain P1

  21. Sulfolobussolfataricus is one of the first extremely thermophilic archaea to be discovered (by Wolfram Zillig and Karl Stetter in Pisciarelli, Italy). Pisciarelli, Italy (near Naples)

  22. Other Extreme Locations Iceland Tim Molson Kamchatka, Russia Alicia Wagner Calzada Japan

  23. Relatively easy to culture

  24. 4 New virus families in Solfolobus in the last few years accepted by ICTV

  25. 4 New families in four different species of Solfolobus in the last few years accepted by ICTV Family Morphology Genome Size Fuselloviridae lemon-shaped circular, supercoiled ds DNA 15 Rudiviridae rod-shaped linear ds DNA 33-36 Lipothrixviridae* rod-shaped linear ds DNA 16 SNDV-like droplet shaped circular 20 *Also found in Thermoproteus tenax

  26. 4 New families in Solfolobus in the last few years Accepted by ICTV 1 1 New Families 2 3 4

  27. COMPARISON OF PHAGE: Non-Thermophilic vs Thermophilic Non-Thermophilic -similar morphology, genetic organization, and lifecycle 100 – 200 ORF ****Very prevalent outside host Family namemorphologygenomesize Myoviridae tailed phage linear ds DNA (organized) large up to 170 kb Siphoviridae tailed phage linear ds DNA (organized) large up to 121 kb Thermophilic -rarely found outside cells 20 – 40 ORF Unlike anything identified, unlike each other Family namemorphologygenomesize Fuselloviridae lemon-shaped circular, supercoiled ds DNA 15 Rudiviridae rod-shaped linear ds DNA 33-36 Lipothrixviridae rod-shaped linear ds DNA 16 SNDV-like droplet shaped circular 20

  28. Non-Thermophilic Thermophilic Fuselloviridae Halophage

  29. G. Unique • H. Unique • I. Unique D. SSV-like E. SIRV-like F. SIFV-like

  30. Model developed at the Salk Institute Based on crystal structure Found 12 Propeller shaped proteins

  31. Extreme Diversity • Diversity of Viruses in Sulfolobus and other extreme thermophiles is amazing. • It is estimated that 10 families of viruses can be isolated from one species of Sulfolobus

  32. Rarely found outside host • Once reproduced, they reside within the Sulfolobus cells and slip out without destroying their host in very small numbers (1 or 2) - Lysogenic • Their non-lytic character allows the viruses to remain inside the modulated cellular environment of the Sulfolobus cells; it limits the time the viruses are exposed to the acidic environment outside.

  33. Origin of Viruses Virulent viruses are probably "new" Latent Viruses are probably "old" No known Virulent Viruses in Extreme Thermophiles Shuttle vector has been developed recently to explore genetics of Sulfolobus.

  34. Two families of viruses infect Halobacteria Methogens Six novel families exist in extreme thermophilic acidophile Sulfolobus sxxx! In one species of Sulfolobus there exists a greater viral diversity than in any other microorganism!

  35. Viruses of Microbial ExtremophilesWho, What, When, Where?And How! • Who? – Viruses of Sulfolobus solfataricus • What? – Thermophilic acidophile • When? – From the beginning of ‘life’ • Where? – Everywhere on Earth and… • And How! – Answers to questions about the origin of life and life beyond Earth!

  36. Viruses of Microbial ExtremophilesWho, What, When, Where?And How! NASA – NSF – TSU Fourth Annual RESEARCH SYMPOSIUM “Developing Student Research” Rhonda L. Lane*, Tennessee State University E. Myles Lewis, Tennessee state University Todd Gary, Tennessee State University Kenneth Stedman, Portland State University

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