Antibiotics In the Food Supply Flashcards
What are the 4 antibiotic categories?
1) very high importance
2) high importance
3) medium importance
4) low importance
Does banning antibiotic work?
Yes. After bans you see a leveling off, and even a decrease of the AMR in the community.
What is synercid?
Synercid (category I) is a semisynthetic antibiotic that is approved to treat MRSA in humans
virginiamycin acetyltransferases confers resistance to ______________ also confers resistance to _____________
virginiamycin (category IV)
Synercid (category I)
Manure resistome leads to ____________ and then to _____________
soil resistome and crop resistome
Antibiotics used in food-producing animals help select for the presence of antibiotic _______________and antibiotic ______________
resistance genes (ARGs) resistant bacteria (ARBs)
What are the different mode of action for antibiotics? (4)
- Inhibit cell wall synthesis
- Inhibit protein synthesis
- Inhibit DNA synthesis
- Inhibit folic acid synthesis
Antibiotics are used for what 4 things:
1) Disease treatment
2) Disease prevention
3) Growth promotion
4) Human
What is AMR?
AMR describes the decreased susceptibility of a multitude of microbes to a broad spectrum of single or multitude antibiotics
Antibiotics can be classified into 2 categories, what are they?
Bactericidal and bacteriostatic
Talk to me about bactericidal antibiotics, give me a few characteristics…
- Bactericidal antibiotics kill bacterial cells
- They target key cell structures (biosynthesis of the cell wall, or DNA)
- B-lactam antibiotics family, aminoglycosides, quinolones
Talk to me about bacteriostatic antibiotics, give me a few characteristics…
- Inhibit further growth
- Target protein synthesis
- Macrolides, tetracyclines, sulfonamides, telithromycin
What are the 2 schools of thought for AMR in the food chain?
1) The Food Chain Propagates AMR Infections in Humans:
- AMR foodborne pathogens are common
- AMR in commensal bacteria on food items are is also very common
- The AMR genepool in food must therefore be very high
- It is very likely that humans are being continuously exposed to AMR genes through the food chain
2) The Food chain does not propagate AMR infection in humans:
- The actual number of pathogens in foods is very small
- The actual number of AMR pathogens in food is very, very small
- Do any of these genes actually move to organisms in the GI tract?
AMR due to genetic changes can be transmitted by _______ or _________ gene transmission
vertical or horizontal
Horizontal Gene Transfer (HGT) mediates the spread of AMR to bacterial cells by mobile genetic elements like : (name 3)
- plasmids
- transposons
- integrons
Horizontal gene transfer can occur via ___________, _________ & _____________
conjugation, transformation, and transduction
What are the mecanisms used by AMR bacteria? (5)
1) Export
2) Destruction
3) Modification
4) Altered receptors
5) Membrane composition
What is another name for Colistin:
Polymyxin E
What is Colistin?
is a very old antibiotic that was not used in humans due to kidney toxicity. However, due to the spread of AMR use became more prevalent in the 1990’s
TRUE OR FALSE: AMR can be detected from the whole genome sequences of bacteria
TRUE
What does the disk diffusion test measure?
the sensitivity of a bacteria to a specific antibiotic
Explain the disk diffusion test :
- It usesantibiotic discswhich are placed on an agar plates containing a lawn of bacteria, and the plate is left to incubate
- If an antibiotic stops the growth of the bacteria, this is called the zone of inhibition
- The size of this zone depends on many factors, one being how effective the antibiotic is at stopping the growth of the bacterium, another is the rate diffusion of the antibiotic within the agar medium and varies based on the molecular configuration of the antibiotic
- Once the zone diameter is measured it must be compared to a database of zone standards to determine if the bacterium being studied is susceptible, moderately susceptible or resistant to the antibiotic in question
What does MIC stands for:
minimal inhibitory concentration (lowest concentration of a drug at which no visible growth occurs)
What are Sensititre MIC plates?
- 96-well plates that contain lyophilized antibiotics configured to determine the MIC to a variety of antibiotics
- Dilutions of bacteria with a usable carbon source are inoculated into each well of the plate
- The plates can be inspected visually or with a plate-reader to determine the MIC for each antibiotic
