Antibiotics Flashcards
What is anti microbial chemotherapy?
Selective toxicity - kill/inhibit microbe without harming patient
Bacteria - primary attack of the cell wall
Describe the cell wall in antibiotics
Can be either gram positive or gram negative
Have cross linked chains of peptidoglycan
Interfere with the cell wall biosynthesis
Which has a thicker peptidoglycan layer gram positive or gram negative bacteria?
Gram positive
Which agents are most likely to interfere with cell wall synthesis in antibiotics?
Glycopeptides
Beta lactam agents
Which of gram positive or gram negative bacteria is lipohpilic?
Gram negative
May prevent large hydrophilic molecules from reaching the cellular target
What are the bacteriostatic and bactericidal properties of antibiotics
Bactericidal = kill bacteria Bacteriostatic = inhibit reproduction and growth
Name the three beta lactam antibiotics
Penicillins
Cephalosporins
Clavams
Which bacteria does penicillin work against?
Gram positive and gram negative
How do Cephalosporins work?
They increase stability against beta lactamase, but some can decrease against some bacteria
How do Clavams work?
Inhibit staphylococcal beta lactamase and most types produced by gram negative bacteria
What are Rifamycins used for treament of?
TB meningitis
What do aminoglycosides inhibit?
Bacterial protein synthesis
What do macrolides and tertracyclines inhibit?
Bacterial protein synthesis
What do glycopeptides inhibit?
Bacterial cell wall peptidoglycan synthesis
Name the two types of anti fungal antibiotics
Griseofluvin
Polyenes
What are diamonpyridine derivatives highly active against?
Human cells
Protozoa
Bacteria
What is the initial phase of treament for TB
Combination of 3 drugs to reduce bacterial levels as rapidly as possible
What is the second phase of treatment of TB?
Continuation phase, combination of two drugs
What do Nitrofuran compounds treat?
UTIs
What are imidazole derivatives active against?
Bacteria, fungi, viruses, protozoa and helminths
What is Terbinafine?
Antifungal
What do quinolones work against?
Work against The enzymes in maintaining the integrity of the supercoiled DNA helix during replication and transcription
How is natural drug resistance achieved ?
Impaired cell wall or cell envelope penetration, enzymatic inactivation or altered binding sites
How is acquired drug resistance achieved?
May result from a mutation, adaptation or gene transfer
