Lecture 8: Bacterial growth and metabolic pathways Flashcards
what do rod shaped bacteria undergo?
binary fission
what are the 4 types of unequal product from cell division?
- simple budding
- budding from hyphae
- cell division of a stalked organism
- polar growth without differentiation of cell size
what 3 main players facilitate bacterial growth?
MreB, FtsZ and Min system (MinCDE)
what is MreB?
- actin homologue
- bacterial cytoskeleton
- elongation growth by incorporation of new cell wall material
- rotate along inner membrane
what is FtsZ?
- tubulin homologue
- cytokinesis ring
- element of septum formation, constriction and cell division
- dynamic at ring midcell
what is MinCDE?
- midcell selection
- positions FtsZ at midcell
what is an example of a bacteria that doesn’t divide in the typical way?
B.subtilis since no cell wall constriction occurs during cell division and instead daughter cells separate through autolysins (enzymes that break down cell walls)
what are the 3 main factors determining culture growth?
- nutrient availability
- oxygen levels
- temperature
what 4 types of bacteria prefer low O2?
- aerotolerant anaerobes
- facultative aerobes
- microaerophiles
- anaerobes
what are 4 categories of temperature preference in bacteria?
- psychrophile: cold 4
- mesophile: human temp 39
- thermophile: warmer 60
- hyperthermophile: VERY hot 80-110
what are the 2 bacterial energy sources?
phototrophs (light) and chemotrophs (oxidation of (in)organic compounds)
what are the 2 bacterial electron sources?
lithotrophs (reduced inorganic molecules) and organotrophs (organic molecules)
what are the 3 bacterial carbon sources?
autotrophs (CO2) and heterotrophs (organic molecules from other organisms)
what performs denitrification in E.Coli?
nitrate reductase
what does anaerobic respiration use as terminal electron acceptors?
SO4, NO3, CO2 and fumerate
when does fermentation occur?
if there is no oxygen as the terminal electron acceptor
why is fermentation inefficient?
only produces 2 ATP
what is homofermentative?
only lactate is produced from fermentation
what is heterofermentative?
other mixed products are made from fermentation
