Bacterial Requirements Temperature and Oxygen Measurement of Microbial

Bacterial Requirements Temperature and Oxygen

Measurement of Microbial Growth n n CFU Direct q Viable Plate Counts n n n q q q n Serial Dilutions Pour Plate Spread Plate Membrane Filtration Counting Chamber MPN (fecal, H 20, food) Indirect q q Turbidity Metabolic activity

Metabolic Classifications n n n Temperature Oxygen requirements p. H Pressure Radiation

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

Temperature Requirements

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

Anaerobic Culture Methods

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

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

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

Gas Pack Jar: CO 2 anaerobic System TSA agar plate 4 quadrants Label bacteria Label O 2 H 2 O added to envelope to Produce H 2 and CO 2 Na. HCO 3, Na. BH 4 H 2 + O 2 => H 2 O

Aerobic / Anaerobic Lab Test Results aerobe FA aerotolerant anaerobe

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

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

Oxygen Requirement Classification

BHI results

Thio Tubes

Bacterial Examples of O 2 Groups n Obligate Aerobes q n Microaerophiles q n q E coli Clostridium Facultative Anaerobes q q n Streptococcus Lactobacillus Obligate Anaerobes q n H. pylori Aerotolerant aerobes q n Pseudomonas E. coli Stapylococcus Capnophilic q Campylobacter Staph

p. H Groups n Acidophile q q n Neutrophile q q n Bacillus acidocaldarius Lactobacillus acidophilus E. coli Staphylococcus aureus Akaliphile q q Streptococcus pneumoniae Nitrobacter sp.

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