Bacterial Requirements Temperature and Oxygen

Measurement of Microbial Growth CFU Direct Viable Plate Counts Serial Dilutions Pour Plate Spread Plate Membrane Filtration Counting Chamber MPN (fecal, H20, food) Indirect Turbidity Metabolic activity

Metabolic Classifications Temperature Oxygen requirements pH Pressure Radiation

Growth Curve Labeled Phases Lag phase Adaptive Start metabolism 1-3 days Log phase Generation time doubles Most metabolically active Stationary phase Growth = death Death phase Requirements decrease Possible spore formation

Temperature Requirements

Temperature Experiment 4 TSA plates Label Temperature 4 different settings Wheel spoke pattern 5 Bacteria 4 SAB broth/Durham tube S. cerevisiae

Anaerobic Culture Methods

Oxygen Requirements Obligate Aerobes Microaerophiles Aerotolerant anaerobes Obligate Anaerobes Facultative Anaerobes Capnophiles

BHI deeps Brain/Heart infusion Melt Label Inoculate Ice Bath Organism Inoculate Pipette or loop Roll tube to distribute Ice Bath Incubate @ 37°C

Fluid Thioglycollate Broth Sodium thyioglycollate Reduction (redox) Pink if oxidized Label tubes Thio Organism Inoculate with loop Incubate @ 37°C

Gas Pack Jar: CO2 anaerobic System TSA agar plate 4 quadrants Label bacteria Label O2 H2O added to envelope to Produce H2 and CO2 NaHCO3, NaBH4 H2 + O2 => H2O

Aerobic / Anaerobic Lab Test Results aerobe FA aerotolerant anaerobe

Physical Requirements: Temperature Psychrophile Unsaturated FA in cell membrane Cold temperatures Psychrotroph (facultative psychrophiles) Refrigeration Room temperature Mesophile Warm Blooded Animals Thermophile/Hyper- Saturated FA in cell membrane

Bacterial Examples: Temperature psychrophile psychrotroph mold Vibrio mesophile thermophile Archaea E coli

Oxygen Requirement Classification

BHI results

Thio Tubes

Bacterial Examples of O2 Groups Obligate Aerobes Pseudomonas Microaerophiles H. pylori Aerotolerant aerobes Streptococcus Lactobacillus Obligate Anaerobes Clostridium Facultative Anaerobes E. coli Stapylococcus Capnophilic Campylobacter E coli Staph

pH Groups Acidophile Neutrophile Akaliphile Bacillus acidocaldarius Lactobacillus acidophilus Neutrophile E. coli Staphylococcus aureus Akaliphile Streptococcus pneumoniae Nitrobacter sp.

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