Archaea

Question 1

Halophile water balance

Answer 1

Maintain osmotic balance by accumulation/synthesis of comparable solutes
Halobacterium pump large amounts of K+ INTO cell
-intercellular K+ exceeds extracellular Na+
- concentration and positive water balance is maintained.

Question 2

Bacteriorhodopsin

Answer 2

Can absorb light energy and can pump protons across membrane

Question 3

Haloarchaea in ionic environments

Answer 3

Cell wall composed of glycoproteins –> stabilized by Na+
– has highly acidic proteins
Fewer hydrophobic amino acids

Question 4

Thermoplasmalates

Answer 4

Thermophilic and acidophilic

Facultative aerobes via sulfur respiration

Question 5

Structural features improving thermostability

Answer 5

Highly hydrophobic cores
Increased ionic interaction on protein surfaces
Chaperonins (heat shock proteins refold partially denatured proteins)
High intracellular solute levels stabilize DNA