Environmental Microbiology Lecture 5

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Environmental Microbiology Lecture 5

• Bacterial Growth

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(No Transcript)
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Bacterial growth rate
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Growth rate calculation
N N02n n3.3(logN logN0)
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Doubling times for some common bacteria under
optimal conditions of growth
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Growth cycle
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Batch culture effect of nutrient
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Continuous culture Chemostat
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Chemostat effects of nutrient and dilution rate
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Environmental factors for bacterial growth

• Temperature
• pH
• Salinity
• Water activity
• Oxygen

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Temperature
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pH
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Salinity
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Environmental Microbiology Lecture 6

• Bacterial production and biomass

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What is bacterial production?

• Secondary production
• Synthesis of bacterial biomass

P µN
P production µ growth rate N bacterial cell
number (biomass)
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How to measure biomass (cell number)?

• Direct count
• Viable count
• Epifluorescence microscopy
• AODC
• DAPI
• SYBR Green

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How to measure biomass (cell number)?
Flow cytometry
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How to measure bacterial production?

• Thymidine incorporation into DNA
• Leucine incorporation into Protein
• Adenine incorporation into DNA and RNA