Unit 6 & 7 Zoom Flashcards
Structurally, what do penicillin and cephalosporin have in common?
Do these two antibiotics target the same cell structure?
Beta lactam ring
Yes, it targets the CW in a similar way
(Affects only the structure that’s supposed to be made when the cell divides)
What does Endotoxin lipid A cause?
- Fever
- Shock
- Malaise/lethargy
- Blood pressure drop
- Blood coagulation
What phase of bacterial growth would you think antibiotics, like B-lactams, will be most effective? Why?
What other classes of drugs would also be most effective at the phase of bacterial growth?
Log phase; because these antibiotics prevent new CW to be made; it doesn’t affect already present CW
Those that affect protein and nucleic acid synthesis as well as metabolism would also be effective
What microbe is susceptible to INH and ethambutol?
What does INH do in this microbe?
(Usually given together)
Used against mycobacterium
INH looks like niacin (vitamin B6) so it can’t make NADH, interferes w/ mycolic acid synthesis
Why can’t you use old medication?
With age it becomes less effective
Not full dosage because there’s less
Why shouldn’t you use tetracycline while pregnant?
It binds calcium;
The baby needs calcium for bone and teeth growth
What is an analog?
A molecule that looks similar to another molecule so it should work similarly;
An analog of tetracycline can target protein synthesis and prevent codon recognition
Why do they use a cocktail for HIV?
So it can target multiple sites;
It is less likely for HIV to be resistant to every drug at each site
How might inhibition of tubulin from drugs effect mitosis and flagella?
No microtubule formation -> no cell division
Microtubules are responsible for moving the chromosomes to each side for cell division
No tubulin -> no movement for flagella
How does antibiotic resistance occur?
Antibiotics kill non resistant bacteria but leaves resistant bacteria and that bacteria is able to pass the gene and turn every other bacteria and make them resistant
By what methods can a bacterium acquire antibiotic resistance?
New mutations of chromosomal genes
Acquisition of R plasmids via transformation and conjugation
What does B-lactam target?
The cell wall
What are 4 mechanisms of resistance?
- An enzyme to destroy or inactivate the antibiotic
- Prevent/slow transport of the drug into the cell or pump it out faster than it can work
- Change the drug’s target or change metabolism slightly
- Biofilms can act to protect its community of microbes from antibiotics
What are the 5 stages of infectious disease in order?
- Incubation
- Prodromal
- Illness
- Decline
- Convalescence
Describe the 5 stages of infectious disease
1. Incubation: between the time when you were exposed and the mechanism of disease (no signs or symptoms)
2. Prodromal: when the infectious agent starts multiplying and induces an immune response (innate)
3. Illness: start getting more localized or systemic signs and symptoms of a particular disease (cough, fever, rash, etc.)
4. Decline: when the pathogen number is lowered or reduced in the body and reduction of signs and symptoms (secondary infection may arise cause of weak immune system)
5. Convalescence: body functions are going back to normal (no signs and symptoms, body starts to repair itself)
