Back to notes
What is selective toxicity in antibiotics?
Press to flip
Selective toxicity refers to the ability of antibiotics to target bacterial cells without harming human cells, exploiting differences such as cell wall presence and ribosomal structure.
Why does overuse of antibiotics lead to antibiotic resistance?
Overuse creates selective pressure that increases the prevalence of resistant bacteria, which can survive treatments and pass their resistance traits to other bacteria.
Differentiate between bactericidal and bacteriostatic antibiotics.
Bactericidal antibiotics kill bacteria directly, whereas bacteriostatic antibiotics inhibit bacterial growth, relying on the immune system to eliminate the infection.
What are some common side effects of antibiotics?
Common side effects include gastrointestinal symptoms such as upset stomach, nausea, and diarrhea, as well as potential allergic reactions and yeast infections.
How do antibiotics targeting protein synthesis distinguish bacterial from human ribosomes?
These antibiotics target differences in the structure of bacterial ribosomes, which unlike human ribosomes, are the site of protein synthesis critical for bacterial growth.
What is the primary action of fluoroquinolones in bacterial inhibition?
Fluoroquinolones inhibit bacterial DNA synthesis by blocking topoisomerase II and IV enzymes crucial for DNA replication and transcription.
What is the significance of using antibiotics only when necessary?
Prudent use helps preserve their effectiveness, reduces side effects, and minimizes the risk of developing resistant bacterial strains.
Describe two mechanisms through which bacteria can develop resistance to antibiotics.
Bacteria may produce enzymes like beta-lactamases to neutralize antibiotics and alter their ribosomes to prevent antibiotics from binding.
How can inappropriate use of broad-spectrum antibiotics negatively impact gut flora?
These antibiotics can kill beneficial bacteria, altering gut microbiota composition, leading to issues like antibiotic-associated diarrhea or opportunistic infections.
What is the contribution of antibiotics to increased life expectancy?
By effectively treating and controlling bacterial infections that previously led to high mortality, antibiotics have significantly increased human life expectancy.
Name an antibiotic that works by disrupting cell membranes.
Polymyxins and daptomycin are examples of antibiotics that disrupt bacterial cell membranes.
Mention two examples of antibiotics that inhibit protein synthesis.
Neomycin and azithromycin are examples of antibiotics that target bacterial ribosomes to inhibit protein synthesis.
Why are yeast infections a potential side effect of antibiotic use?
Antibiotics can disrupt normal bacterial flora, allowing yeast, which are not affected by antibiotics, to overgrow, leading to infections.
How might antibiotics contribute to the development of Clostridium difficile infections?
Broad-spectrum antibiotics can disrupt normal gut flora, leading to overgrowth of resistant species such as Clostridium difficile, causing severe intestinal issues.
What role do beta-lactams play in inhibiting bacterial cell wall synthesis?
Beta-lactams, such as penicillins and cephalosporins, inhibit cell wall synthesis by disrupting the peptidoglycan layer, leading to bacterial cell rupture.
Previous
Next