Flashcards in Microbial metabolism Deck (25):
1. Initial period of adaptation to a new environment2. Increase in metabolic activity3. Sensitive to antimicrobials4. Little to no cell division
During what stage(s) are bacteria susceptible to antimicrobials?
1. Lag2. Exponential
1. Rapid multiplication by binary fission2. Most susceptible to antibiotics
1. Nutrients depleted, waste products accumulate2. Decreased growth rate3. Spore forming bacteria initiate sporulation
During what growth phase do spore forming bacteria begin sporulation?
More bacteria die than are generated
Bacteria that require oxygen and metabolize by respiration
Bacteria that are inhibited or killed by oxygen and utilize fermentation exclusively for energy production
1. Bacteria that grow well under aerobic or anaerobic conditions. If oxygen is available they respire, if not they use fermentation2. Majority of bacteria
Require 5-10% oxygen for optimal growth
What does catalase (or peroxidase) do?
Breaks down H2O2 into O2 and H2O
What does superoxide dismutase do?
Detoxifies O2- to H2O and O2
What must bacteria synthesize to make nucleic acids, making it a target for antibiotics?
What do quinolones target?
What drug class targets DNA gyrase?
What does rifampin target?
Bacterial DNA-dependent RNA polymerase
What is the precursor subunit of peptidoglycan?
UDP-N-acetyl muramic acid
Where is UDP-N-acetyl muramic acid synthesized?
What is added to the 3rd carbon of UDP-N-acetyl glucosamine to make UDP-N-acetyl muramic acid?
What occurs once UDP-NAM is made?
5 amino acids are added to it
What happens to the UDP-NAM-pentapeptide after it is formed?
Transferred from UDP to bactoprenol phosphate at membrane surface
What happens to bactoprenol-NAM-pentapeptide to form the final disaccharide-pentapeptide precursor product?
NAG is transferred from UDP-NAG to it
How are the peptide side chains linked together?
What is transpeptidation?
1. Cross linking of peptide chains by peptide bond exchange2. Occurs on outer leaflet of plasma membrane