Microbiology Archaea

  1. Two groups of Archaea
    • 1.) Euyarcheota (broader metabolism)- Methanogens
    • 2.) Crenarchaeota - thermophiles that metabolize sulfer (anaerobic reduction or aerobic respiration)
  2. What makes archaea biochemistry unique?
    • Mathane production
    • no peptidoglycan - pseudomurein
    • differences in glycolytic pathway
  3. How are Archael lipids different?
    • L-glycerol instead of D
    • Ether links, not ester
    • Branched chains of lipids - isoprene and all saturated
  4. Archaeal Genome vs Bacterial vs Eukarya
    • Bacteria: Circular, have operons
    • Eukarya: Introns, TATA, TFB, prot similiar to histones
  5. Crenarchaeota Characteristics
    • Irregular shapes
    • Unique lipid - Crenarchaeol
    • Most live at high temps and anaerobic/acidic env.
    • utilize minerals that were reduced by high temp water
  6. Desulfurococcales Characteristics + ex
    • No cell wall - S-layer (mono prot or glycoprot)
    • Reduce sulfer at high temps
    • Variable shapes
    • ex : Ignicoccus pyrodictium
  7. Sulfolobales Characteristics + ex
    • Oxidize sulfer at high temp
    • produce sulfuric acid
    • Needs heat and acidity, grows easily with conditions
    • No cell wall - thick S-layer
  8. Crenarchaeota - Which kind are found where? What temps? Examples
    • High numbers in ocean, amount depends on season
    • Mesophilic - ocean, plant roots ex: Nitrosopumliales
    • Psychrophilic - ice and seawater in antarctica ex: cenarachaeum (deepwater sponge)
  9. Nitrosopumilales
    • Oxidize ammonia, and fix CO2
    • common in ocean and soil
  10. Euryarchaeota: Methanogenesis
    • Needs anaerobic env
    • Hydrogen=electron donor
    • CO2, acetate, formate=electron acceptor - creates methane
    • Cofactors - hold c during process - coenzyme M, methanofuran, cofactor F420
  11. Where are methanogens found?
    Anaerobic env - landfill, marine sediment/flood soil, Rumen, Human gut
  12. Euryarchaeota: Halophile characteristics
    • Require >1.5 M NaCl (grow best at 4.3 M=pH 7)
    • Organic molecules raise internal osmolarity
    • High GC DNA (prevents denaturation of DNA in high salt)
    • elongated, round, flattened shape
  13. What is Bacteriorhodopsin?
    found in Euryarchaeota, and pumps out H+
  14. What is Halorhodopsin?
    Pumps in Cl-
  15. Where does power for flagellum come from?
    Na gradients created by a proton gradient that is used to pump out NA
Card Set
Microbiology Archaea
Microbiology Archaea