BSC 310 Lecture Notes - Lecture 22: Osmosis, Intracellular Ph, Osmotic Concentration

• School: University of Alabama
• Department: Biological Sciences
• Course: BSC 310
• Professor: Julie Olson

Document Summary

Thermophiles- organisms with growth optima above 45 degrees. Hyperthermophiles- organisms with growth optima above 80 degrees celsius (cid:1) Typically found in nature associated with volcanic environments including hot springs, steam vents, and hydrothermal vents but also industrial applications and some compost piles or silage (cid:1) Above 65 degrees celsius, only prokaryotes are present and members of the archaea typically have higher temperature optima (cid:1) Most heat tolerant organism known is methanopyrus, a methanogenic. Archaea capable of growth at 122 degrees celsius (cid:1) Nonphototrophic organisms can grow at higher temps than phototrophic organisms (cid:1) (cid:1) (cid:1) Enzymes must be extremely heat stable and function optimally at high temperatures (cid:1) Typically have little amino acid sequence differences from mesophilic enzymes. Critical amino acid substitutions at a few key locations provide a more heat-stable folding structure (cid:1) Also increase ionic bonds between basic and acidic amino acids to resist being unfolded (cid:1) (cid:1) (cid:1) (cid:1)