Chapter 2: Diversity of Microorganisms

• COCCI

  A) Diplococci

  B) Streptococci

  C) tetrad

  D) sarcina

  E) staphylococci

  
• RODS

  A) Chain of bacilli

  B) flagellate rods

  C) spore-former

  
• SPIRALS

  A) Vibrios

  B) Spirilla

  C) spirochaetes

  
• 11 phyla in Woese
• 36 phyla hugenholtz
• 52 phyla rappe and Giovannoni
• Critical ecosystem players: Phototrophs
• 5 bacterial phyla containing phototrophs:

  • Firmicutes
  • Proteobacteria
  • Chloroflexi
  • Cyanobacteria
  • cholorobi
• DIAGRAM

  A) oxygenic

  B) anoxygenic

  C) Cyanobacteria

  D) Purple bacteria

  E) green bacteria

  F) purple non-sulfur

  G) purple sulfur

  H) green non-sulfur

  I) green sulfur

  J) bioelectrochemical systems

  
• New Discovery: Zetaproteobacteria
• Nitrogen-fixing bacteria - can participate in obligate or facultative symbioses.
• A Case of extreme polyploidy - Epulopiscium
• LABEL

  A) Epulopiscium

  B) e.coli

  C) paramecium

  
• Three domains that Archaea are most ecologically diverse:

  • Psychrophiles
  • Hyperthermophiles
  • Halophiles
• Psychrophiles - are organisms capable of growth and reproduction in cold temp and are often xerophilic and halophilic as well.
• Hyperthermophiles - are defined as microorganisms that optimally grow at temperatures above 80 deg C or that can grow temp above 90 deg C.
• Halophiles - are microorganisms that require certain concentrations of salt to survive and they are found in both Eubacterial and archaeal domains of life.
• Acidophiles - organisms are those that thrive under highly acidic conditions.
• Methanogens - microorganisms that produce methane as metabolic byproduct in hypoxic conditions.
• Archaeal Traits:

  • cell membrane lipids
  • cell wall components
  • certain metabolic pathways
  • certain genome features
• Archaea Traits

  • Archaea domain contains single-celled organisms.
  • Archaea are prokaryotic organisms and do not have a membrane-bound nucleus.
  • Lack internal cell organelles
  • Archaea reproduce by binary fission
  • One circular chromosome
  • Use flagella to move around in their environment as do bacteria.
• Archaea Lipids

  • Are different from those of bacteria and eukaryotes
  • Use L-glycerol, not D-glycerol
  • Have ether (R–O–R) not ester (R–COO–R) links
• Differ from Bacteria and Eukarya in having branched chain hydrocarbons attached to glycerol
• Label

  A) Diphytanylglycerol Diether

  
• Label

  A) isoprene unit

  
• label

  A) Macrocyclic diether

  
• label

  A) tetraether

  
• Label

  A) cross-linked tetraether

  
• Label

  A) cyclopentane ring

  
• Pseudopeptidoglycan in methanogens

  • N-acetyltalosaminuronic acid 
  • b(1,3) linkages instead of b(1,4)
  • -Are therefore resistant to lysozyme
• Different types of cross-bridges

  • Are therefore resistant to penicillin 
• Other Archaea possess no cell wall at all.

  • -Only an S-layer composed of protein
• Cell envelopes 

  • varied S layers attached to plasma membrane
  • pseudomurein (peptidoglycan-like polymer)
  • complex polysaccharides, proteins, or glycoproteins found in some other species
  • only Ignicoccus has outer membrane
• Chromosome - single (closed circular) molecule of double-stranded DNA (one-third to one-half as much DNA per cell as found in bacteria such as E. coli)
• Plasmids - these pieces of extrachromosomal DNA may make up as much as 25-30% of cellular DNA
• Endospores - not formed
• flagella - very long protein (flagellin) polymers that provide motility
• Pili- long thin protein polymers that act as cell "anchors" to various surfaces and can assist in attaching archaeal cells to facilitate DNA transfer from
• Glucose is catabolized by several variants of the Entner-Doudoroff (ED) and Embden-Meyerhoff-Parnas (EMP) pathways that rarely occur in bacteria.
• The process of methanogenesis is unique to Archaea.