Bacterial Growth and Metabolic Pathway Flashcards
What type of cell division does a rod-shaped bacteria undergo?
Binary fission
Describe binary fission in a rod-shaped bacteria:
- Cell elongation
- Septum formation
- Completion of septum; formation of walls; cell separation
Give examples of rod-shaped bacteria that undergo binary fission:
- Escherichia coli
- Salmonella typhi
- Pseudomonas aeruginosa
How can cell division differ in bacterial growth?
Different morphological forms
What are the two different morphological forms of cell division?
- Equal products of cell division
2. Unequal products are so division
Is binary fission an unequal product of cell division or an equal product of cell division?
Equal products of cell division
What are four types of unequal products of cell division?
- Simple budding
- Budding from hymphae
- Cell division of stalked organisms
- Polar growth without differentiation of cell size
What are the three main players that facilitate bacterial growth at a cellular level?
MreB
FtsZ
Min system
What is MreB?
Actin homologue - bacterial cytoskeleton protein
How does MreB facilitate bacterial growth?
Elongation growth by incorporation of new cell wall material along longitudinal axis
What is FtsZ?
Tubulin homologue - cytokinesis ring
How does FtsZ facilitate bacterial growth?
Fundamental element of septum formation, septum contraction and cell division
What is min system (MinC)?
Midcell selection
How does MinC facilitate bacterial growth?
Robust positioning of FtsZ at midcill and only midcill over the lifetime of each cell
Fill in the gap:
MreB, FtsZ and MinC are highly …… inside the cell
Dynamic
What is the motion of MreB directly coupled to?
Wall synthesis
How does bacterial growth differ with different bacterial species?
- Different shapes
- So different versions of cell division proteins
- and different cell wall-synthesising machines
What factors determine culture growth?
- Availability of nutrients
- Presence or absence of oxygen
- Temperature
How can we describe the growth of bacteria in one generations time?
- mass and cell number doubles
- exponential growth
What are the four phases of bacterial growth phases?
- Lag phase
- Exponential phase
- Stationary phase
- Death phase
What is an anoxic zone?
Lack of oxygen
What is an oxic zone?
Oxygen present and dissociates in liquids
What is the limitation of microorganisms that like to grow in low oxygen conditions?
Difficult to grow in lab due to sensitivity to oxygen
What is one of the most important factors of culture growth of bacteria?
Temperature
What can occur to growth of bacteria in a minimum temperature?
Membrane gelling; transport processes so slow that growth cannot occur
What can occur to growth of bacteria in optimum temperature?
Enzymatic reactions occurring at maximum possible rate
What can occur to growth of bacteria in maximum temperature?
Protein denaturation; collapse of cytoplasmic membrane; thermal lysis
Do all bacteria like the same temperature?
No, each species have their own optimum temperature
What are the three different sources of metabolic diversity?
- Energy source
- electron source
- carbon source
What are the two subtypes of energy sources?
- Phototrophs
- Chemotrophs
What is phototrophs?
Light