BIOL 2051 Chapter : CH 5 NOTES
Document Summary
Chapter 5 - environmental influences and control of microbial growth. Psychrophile: grow well at temperatures: o c 20 c. Example: chlamydomonas- pink snow algae : molecular adaptations of psychrophiles: Membranes have high content of unsat. fatty acids - semi-fluid at low temps. Proteins are more flexible compared to mesophiles or thermophiles. Cryoprotectants can be used to preserve microbial cultures at low temps. 10% dmso (dimethylsulfoxide) & 10% glycerol are commonly used in laboratories to preserve microbial cultures for long time in freezers. Found in warm-blooded animals & many terrestrial & aquatic environments. Examples- escherichia coli (found in the human intestine) Thermophile: 40 c 80 c, optimum temp above 40 c, places thermophiles are found: Some archaea have been found growing at temps above 110 c soils subjected to full sunlight fermenting materials (compost piles) Hot springs: thermus aquaticus is a common hot spring thermophile.
