Lecture 21 and 22 Flashcards
Define chemotherapy
Use of drugs to treat disease
Who noted that some dyes used in histology were toxic to bacteria?
Paul Ehrlich
What was the first effective antisyphilitic?
Salvarsan (Arsenic containing)
What must antimicrobials have?
Selective toxicity
What are classification of antibacterial agents based on the mode of action?
Bacteriostatic, bacteriocidal
What are classifications of antibacterial agents based on their spectrum of activity?
Broad and narrow spectrum
What does penicillin do?
Target peptidoglycan on growing bacteria (inhibits cell wall synthesis)
What is the monomers making up petidoglycan?
N-acetyl glucosamine (NAG)
N-acetly muramic acid (NAM)
What does penicillin bind to?
Bacterial enzymes responsible for cross-linking and inhibits their activity
What is the structure of all penicillins?
beta-lactam ring
What are extremely broad spectrum beta-lactams resistant to most beta lactamases?
Cabapenems
What are the 4 classifications of beta-lactam antibiotics?
Penicillins
Cephalosporins
Monobactams
Carbapenems
Name a glycopeptide antibiotic
Vancomycin and teicoplanin
How do glycopeptide antibiotics work?
Inhbit cell wall synthesis of gram + aerobes
What is the difference between how beta-lactams work and glycopeptides?
Beta-lactams: structural analogues of cell wall precursor
Glycopeptides: bind to cell wall precursor
What is the type of inhibition in beta-lactams and glycopeptides?
beta-lactams: competitve inhibition
Glycopeptides: steric inhibition
What does mycobacteria cell wall contain?
Mycolic acid
Name two antimycobacterial antibiotics
Isoniazid
Ethambutol
What are cationic peptides?
Polymyxins
How do polymyxins work?
It competes and displaces cations on lipopetides, detabilising membrane of gram negative bacteria
What competitvely inhibits with folic acid precuror to block folic acid production?
Sulfonamides
Name two classes of ergosterol synthesis inhibting antifungal drugs
Polyenes
Azoles
What drug targets beta-glucans in fungi?
Echinocandins
How do antivirals block initial stages of virus infections?
Entry inhibitors, fusion blockers, stop them being released from their coat, inhibit intergrase
What antiviral inhibits further spread of the infection?
Interferons
