Medical Microbiology Flashcards
What is Antibiotic Resistance?
When infectious agents are able to evolve rapidly and develop resistance to antibiotics
What is Selective Toxicity?
When an antibiotic needs to be toxic to the bacteria , but not to the human patient
What is Narrow Spectrum?
When an antibiotic has a high specificity, meaning that it treats only one or a small class of bacteria (excluding the healthy microbiota)
What is Broad Spectrum?
When an antibiotic can treat both gram-positive and gram-negative as well as a wide range of bacteria (including the healthy microbiota)
What is bacteriostatic?
Antibiotics that will only slow bacterial growth
What is bactericidal?
Antibiotics that kill bacterial cells
What are differences about gram positive?
Stains purple because it traps dye inside cell, has only 1 membrane, and a thick layer of peptidoglycan
What are differences about gram negative?
Stains pink because dye escapes the cell, has a 2nd outer membrane and a thin layer of peptidoglycan
What are similarities between gram positive and gram negative?
They are types of cell walls and the staining procedure is required for both in order to tell a difference
What antibiotics are cell wall inhibitors? (inhibits crosslinking of the peptidoglycan cell wall)
Penicillin, Ampicillin, Cephixime, and Vancomycin
What antibiotics are protein synthesis inhibitors? (binds to small ribosomal subunit)
Streptomycin, Gentamicin, Kanamycin, Erythromycin, Tetracycline, and Chloramphenicol
What antibiotic causes injury to the plasma membrane? (makes it more permeable)
Polymyxin B
What antibiotic is a nucleic acid inhibitor? (inhibits transcription elongation)
Rifampin
What antibiotics are essential metabolite inhibitors? (inhibitor of dihydrofolate)
Trimethoprim and Sulfamethoxazole
How can 2 antibiotics be synergistic?
Synergistic combinations increase the inhibitory activity of either antibiotic alone
