microbiology ch 20 Flashcards
What is selective toxicity?
Selectively finding and destroying pathogens without damaging the host
This is the use of chemicals to treat a disease
Chemotherapy
This is a substance produced by a microbe that, in small amounts, inhibits another microbe
Antibiotic
These are synthetic substances that interfere with the growth of microbes
Antimicrobial drugs
These are drugs that affect a narrow range of microbial types
Narrow spectrum antibiotics
These are drugs that affect a broad range of gram-positive or gram-negative bacteria
Broad spectrum antibiotics
This is an overgrowth of normal microbiota that is resistant to antibiotics
Superinfection
This type of antimicrobial drug kills microbes directly
Bactericidal
This type of antimicrobial drug prevents microbes from growing
Bacteriostatic
What are the five possible actions of antimicrobial drugs?
- Inhibiting cell wall synthesis; 2. Inhibiting protein synthesis; 3. Injuring the plasma membrane; 4. Inhibiting nucleic acid synthesis; 5. Inhibiting the synthesis of essential metabolites
Penicillins prevent the synthesis of this in the cell wall
Peptidoglycan
Antimicrobial drugs can inhibit protein synthesis by targeting these in bacteria
70S ribosomes
Chloramphenicol, erythromycin, streptomycin, and tetracyclines all kill microbes by doing this
Inhibiting protein synthesis
Polypeptide antibiotics change this feature of the membrane
Permeability
Antifungal drugs combine with these in the membrane
Sterols
Ionophore antibiotics allow uncontrolled movement of these
Cations
Antimetabolites compete with these for an enzyme
Normal substrates
This antimicrobial drug contains a beta-lactam ring, and types are differentiated by the chemical side chains attached to the ring
Penicillin
Penicillin prevents the cross-linking of these, interfering with cell wall construction
Peptidoglycans
Chloramphenicol inhibits the formation of these
Peptide bonds
This broad-spectrum antimicrobial is synthesized chemically and binds to the 50S subunit of the 70S ribosome
Chloramphenicol
This broad-spectrum antimicrobial is synthesized chemically and binds to the 50S subunit of the 70S ribosome
Chloramphenicol
These antimicrobials are produced by Streptomyces spp. and can penetrate tissues
Tetracyclines
Tetracyclines interfere with this attaching to the ribosome
tRNA
Are tetracyclines broad spectrum?
Yes