Microbial growth

Microbial growth

1. What is it?

   • Multiplication of cells
     • Binary fission

2. Nutritional stages

   • Carbon, energy, reducing power

3. Cell division

   • Binary/budding
     • Enlarge, cell wall forms transverse septum
       • Daughter cells
   • Septation
     • Selection of site
     • Assembly of dynamic Z ring
     • Linkage of Z to plasma membrane/cell wall
     • Assembly cell wall synthesising
     • Construction of cell and septum formation
   • Cytokinesis

4. Growth curve

   • 4 Phases
     • Lag
       • 'Inactivity'
       • Adapt
     • Exponential
       • MO grow maximally
       • Most uniform
     • Stationary
       • Viable numbers MO remain constant
       • Stop reproduction/rate = death
     • Death
       • MO death exponential
     • Responses

5. Measurement

   • Total cell count
     • Chamber slide
     • Coulter counter
   • Viable count
     • Standard plate count
       • CFU
       • Spread plate
       • Pour plate
   • Optical techniques
     • Visual / absorbance