BIOL 2051 Chapter Notes - Chapter 5: Environmental Factor, Osmosis, Superoxide Dismutase
Document Summary
Chapter 5 - environmental influences and control of microbial growth. Environmental factors that affect microbial growth: temperature, pressure, osmolarity, oxygen ph. 10% dmso (dimethylsulfoxide) & 10% glycerol are commonly used in laboratories to preserve microbial cultures for long time in freezers: mesophiles- midrange optimum temperatures. Found in warm-blooded animals & many terrestrial & aquatic environments: examples- most organisms you are familiar with such as escherichia coli (found in the human intestine) Thermophiles: optimum temp above 40c, some archaean have been found growing at temps above 110c (extreme or hyperthermophile, places thermophiles are found: soils subjected to full sunlight fermenting materials (compost) hot springs. Thermus aquaticus is a common hot spring thermophile. Heat shock response: occurs at high end of temperature range. Emergency proteins produced: help keep proteins from denaturing. Induced by many stressful conditions: heat, high salt concentrations, arid conditions.
