Antimicrobial Drugs

Flashcards about Antibiotics, Antivirals, and Antiprotozoals

What is the main mode of action for Penicillin?

Inhibitor of cell wall synthesis, specifically transpeptidation.

What are some important notes about Penicillin?

True antibiotic from fungus penicillium and semisynthetic; -cidal.

What kind of bacteria do Penicillin V and G work against?

They are both true antibiotics that only work against gram-positive bacteria.

What is the main mode of action for Cephalosporin?

Inhibitor of cell wall synthesis, specifically transpeptidation.

What are some important characteristics of Cephalosporin?

True antibiotic from fungus Acremonium (formerly Cephalosporium); -cidal; broad spectrum.

What type of bacteria does Cephalosporin work against?

Works against gram-positive, gram-negative, pseudomonas, and MRSA.

What is the main mode of action for Carbapenem?

Inhibitor of cell wall synthesis, specifically transpeptidation.

What are the key characteristics of Carbapenem?

Semisynthetic, modified versions of penicillin and cephalosporins; -cidal; broad spectrum.

What is the main mode of action for Vancomycin?

Inhibitor of cell wall synthesis; Inhibits transpeptidation because it doesn’t allow for the removal of the terminal alanine.

What are important characteristics of Vancomycin?

True antibiotic produced by bacteria: Streptomyces orientalis; -cidal; narrow spectrum.

What type of bacteria does Vancomycin work against?

Works against gram-positives only—including staph, strep, (bacillus + clostridium—spore formers) and entero.

What is the main mode of action for Aminoglycosides?

Protein synthesis inhibitor; Bind to 30s subunit of ribosome and inhibit translocation and causes misreading of mRNA.

What are important characteristics of Aminoglycosides?

True antibiotic made by bacteria streptomyces spp. Gentamicin made by bacteria Micromonospora sp; -cidal; broad spectrum.

What aerobic gram-negative bacteria is Gentamicin used for?

Gentamicin is used for aerobic gram-negative bacteria which include Proteus, Escherichia, Klebsiella and Serratia.

What is the main mode of action for Tetracycline?

Protein synthesis inhibitor; Bind to 30s subunit of ribosome and inhibit translocation and cause misreading of mRNA.

What are the key characteristics of Tetracycline?

Oxytetracycline and chlortetracycline are true antibiotics made from streptomyces spp. Doxycycline is semisynthetic; -static; broad spectrum.

What type of bacteria does Tetracycline work against?

Work very well against intracellular pathogens (atypical bacteria) Rickettsia, Chlamydia, and Mycoplasma.

What is the main mode of action for Macrolides?

Protein synthesis inhibitor; Bind to 50s subunit of ribosome and prevent translation of proteins.

What are important characteristics of Macrolides?

Erythromycin—true antibiotic comes from bacteria Saccharopolyspora; -static; broad spectrum.

What kind of bacteria do Macrolides work against?

Work against gram positive, mycoplasma, and some gram-negative bacteria.

What is the main mode of action for Lincosamides?

Protein synthesis inhibitor; Bind to 50s subunit of ribosome and prevent translation.

What are important characteristics of Lincosamides?

True antibiotics produced by bacteria streptomyces spp. Clindamycin used to treat CA-MRSA; -static; broad spectrum.

What is the main mode of action for Oxazolidinones?

Protein synthesis inhibitor; Bind to the 50s subunit of ribosome specifically 23s rRNA (the translation site where peptides form) and this prevents 70s formation because there’s no translation.

What are the key characteristics of Oxazolidinones?

Synthetic Linezolid; Static (can be cidal for some bacteria); Broad spectrum.

What is the main mode of action for Chloramphenicol?

Protein synthesis inhibitor; Bind to 50s subunit of ribosome.

What are the key characteristics of Chloramphenicol?

True antibiotic Produced by streptomyces venezuleae; -static; broad spectrum.

What is the main mode of action for Sulfonamides/sulfa drugs?

Metabolic antagonist; Inhibits the making of folic acid by blocking the first step.

What are the key characteristics of Sulfonamides/Sulfa drugs?

Synthetic PABA analog, a key molecule used to make folic acid; Static; Broad spectrum.

What is the main mode of action for Trimethoprim?

Metabolic antagonist; Inhibits the making of folic acid by blocking the second step.

What are the key characteristics of Trimethoprim?

Synthetic Bactirim; Broad spectrum.

What is the main mode of action for Fluoroquinolones?

Inhibit DNA gyrase and topoisomerase 4 (class of topoisomerase 2).

What are the key characteristics of Fluoroquinolones?

Synthetic Ciprofloxacin and norfloxacin; -Cidal; Broad spectrum.

What is the main mode of action for Rifamycin?

Blocks RNA transcription. by binding to RNA polymerase (b- subunit, looks like a claw, if it can’t bind to DNA then transcription can’t occur).

What are the key characteristics of Rifamycin?

Semi-synthetic Rifampin is most used member of this family; -Cidal; Broad spectrum.

What is the mode of action of Tamiflu (oseltamivir)?

Neuraminidase inhibitor.

What is the mode of action of Xofluza (marboxil baloxavir)?

Blocks transcription (doesn’t allow DNA -> RNA).

What is the mode of action of Acyclovir?

Makes an analog that inhibits replication.

What is the mode of action of Vidarabine?

Makes an analog that inhibits replication.

What is the mode of action of HAART?

Curtails HIV resistance via a cocktail of HIV drugs.

What is the mode of action of PrEP?

Nucleoside reverse transcriptase inhibitors producing faulty DNA.

What is the mode of action of Ribavirin?

Nucleotide analog that inhibits RNA synthesis.

What is the mode of action of Epclusa?

Combination drug.

What is the mode of action of Nystatin?

Made from bacteria that competes with fungus and kills it.

What is the mode of action of Amphotericin B?

Binds ergosterol (lipid found in fungal cell membrane) in the membrane.

What is the mode of action of 5-flucytosine?

Uracil analog that disrupts RNA function.

What is the mode of action of Echinocandins?

Blocks synthesis of fungal cell wall by inhibiting B-1,3-glucan synthase.

What is the mode of action of Chloroquine?

Mechanism not precisely known, either nucleic acid or some metabolic process.

What is the mode of action of Dapsone?

Combination therapy drug that inhibits making of folic acid.