CH5-S2 Flashcards
The five actions of antimicrobial drugs:
- Inhibition of cell wall synthesis
- Inhibition of protein synthesis
- Inhibition of nucleic acid replication and transcription
- Injury to plasma membrane
- Inhibition of synthesis of essential metabolites
Beta-Lactam antibiotics:
all contain a beta-lactum ____
bing to penicillin binding proteins and inhibit ______ synthesis
ring, cell wall
_______:
account for 1/3 of all antibiotics administered; relatively broad-spectrum; grouped together based on the type of bacteria that they’re most effective against; most resistant to penicillinases; fewer ________
Cephalosporins, allergic reactions
Cefepime is the fourth generation of cephalosporins; it is _______
pseudomonas
The fifth generation of cephalosporins is ______ (MRSA)
Ceftaroline
2 examples of beta-lactam antibiotics:
Penicillin, cephalosporins
Except penicillin and cephalosporins, give examples of other cell wall inhibitors
Bacitracin, isoniazid (INH), Vancomycin
_____:
cell wall inhibitors; topical; for minor skin infection
Bacitracin
_____:
cell wall inhibitors; treat active tuberculosis
Isoniazid (INH)
_____:
cell wall inhibitors; treatment for septicemia or endocarditis caused by MRSA; used for pseudomenbranous colitis (superinfection of the bowel by Clostridium difficile - produces a toxin that damages the colon mucosa)
Vancomycin
Suggest a antimicrobial drug that use for treatment of urinary tract infections caused by Pseudomonas aeruginosa, or infections of eyes caused by susceptible strains of P. aeruginosa,
which cause injury to the plasma membrane
Polymyxin B
How is the mechanisms of protein synthesis inhibition of Chloramphenicol?
It binds to 50S portion (of prokaryotic ribosome) and inhibits formation of peptide bond
How is the mechanisms of protein synthesis inhibition of Tetracyclines?
It interfere with attachment of tRNA to mRNA-ribosome complex
Protein synthesis inhibition antimicrobial drug:
________:
against chlamydial and mycoplasmal species, H. pylori (GI ulcers), rickettsial infection, Lyme disease
Tetracycline
Protein synthesis inhibition antimicrobial drug:
________:
very toxic, restricted uses, can cause irreversible damage to bone marrow; for typhoid fever, brain abscesses, rickettsial & chlamydial infections
Chloramphenicol
Protein synthesis inhibition antimicrobial drug:
Aminoglycosides:
________- for plague, tularemia, tuberculosis
________- for chest infections, urinary tract infections or septicaemia
Streptomycin,
Gentamicin
Protein synthesis inhibition antimicrobial drug:
Macrolides:
________- for gram-positive cocci (not MRSA), atypical organisms (Chlamydia, Mycoplasma), Legionella pneumophila, and Campylobacter
Erythromycin
Protein synthesis inhibition antimicrobial drug:
Macrolides:
________- similar spectrum but is more active, esspecially versus organisms associated with sinusitis or otitis media, Chlamydia, and Mycobacterium
Azithromycin
Protein synthesis inhibition antimicrobial drug:
Macrolides:
________- has > activity versus Mycobacterium and H. pylori
Clarithomycin
Protein synthesis inhibition antimicrobial drug:
_______:
actions similar to macrolides
Clindamycin
Nucleic acid synthesis inhibition antimicrobial drug:
Fluoroquinolones:
_________, _________ - for urinary tract infection, sexually transmitted disease, gastrointestinal, osteomyelitis, respiratory & soft tissue infections
Norfloxacin, ciprofloxacin
Nucleic acid synthesis inhibition antimicrobial drug:
Fluoroquinolones:
_________, _________ - for pneumonia, bronchitis, sinusitis
Sparofloxacin, levofloxacin
Nucleic acid synthesis inhibition antimicrobial drug:
________ - treatment of symptomatic trichomoniasis and Clostridium difficile infection
Metronidazole
Folate antagonists: ________ and ________ - inhibit folic acid synthesis -> inhibit production of DNA and RNA and amino acids
Sulfonamides and trimethoprim
Mechanisms of antibiotic resistance:
Bacteria produce ____ that inactivate the drug
Bacteria synthesize modified targets against which the drug has a reduced effect
Bacteria reduce permeability to the drug
Bacteria actively export drugs using a “_______”
?, multidrug resistance pump
Antibiotic resistant bacteria:
________:
This strain of the common “staph” bacteria causes infections in different parts of the body including the skin, lungs, and other areas
Resistant to certain antibiotics called beta-lactams, e.g. methicillin and other more common antibiotics such as oxacillin, penicillin and amoxicillin
Methicillin-resistant Staphylococcus aureus (MRSA)
Antibiotic resistant bacteria:
________:
cause infection of the urinary tract, intestines, bloodstream or skin wounds; some enterococci have become resistant to vancomycin
Vancomycin-resistant enterococci
Antibiotic resistant bacteria:
________:
very common is causing infections in humans
produce ESBLs which makes them resistance to antibiotics
in many instances, a very limited group of antibiotics remain effective
Extended-spectrum beta-lactamases (ESBLs) producing gram-negative bacilli
