Extremophiles

Question 1

Extremophiles

Answer 1

An extremophile is an organism that is able to live (or in some cases thrive) in extreme environments, i.e environments with conditions approaching or expanding the limits of what known life can adapt to, such as extreme temperature, radiation, salinity or pH level.
Normal is arbitrary - what is considered normal??

Question 2

Examples of extremophiles

Answer 2

• Temperature
  Strain 121 isolated from a ‘black smoker’ chimney
• Salinity - halophiles - reduce osmotic pressure form the cell - regulating flow of water in and out of the cell
  Hypersaline lake with salinity ~10x sea water - haloarchaea

pH
helicobacter (~pH2) -powerful proton pumps - to maintain a more neutral pH

• pressure
  Moritella sp DB21MT-5 - collected from bottom of mariana trench at 10,898 (=1090 atm)