Lecture 8 Flashcards
Sterilization
No living cells, spores or viruses
Disinfectant/disinfection
Killing, inhibiting, removing organisms that cause disease from inanimate objects
Sanitization
Reducing microbial #’s to levels safe for the public
Antiseptics
Kill or inhibit infection-causing organisms from living tissue
Germicides
Kill certain organisms (Fungicide, viricide, bactericide, etc.)
What are the 5 modes of antibiotic selective toxicity?
- Bind to ribosomes, stop translation
- Stop cell wall synthesis
- Disrupt membranes
- Stop nucleic acid synthesis
- Inhibit metabolic pathways
What are the six factors affecting anti-microbial efficiency?
- Population size
- Population composition
- Concentration of antimicrobial agent
- Length of exposure
- Temperature
- Local environment
What are the two most common mistakes people make when taking antibiotics?
- Failure to follow dosage directions
- Failure to finish
Why are anti-virals much harder to synthesize?
Viruses are obligate intracellular parasites that use host functions to reproduce, leading to difficulty with selective toxicity
Why are anti-fungals/anti-protozoals much harder to synthesize?
Very difficult to achieve selective toxicity when the target cells are also eukaryotic.
Explain the 5 ways that bacteria can be resistant to antibiotics?
- Target modification (RNA sequence changes, tetrapeptide amino acids change, etc.) - Inherent
- Drug altering enzymes (Ex. penicillinase) - acquired
- Drug-degrading enzymes - acquired
- Prevent drug entrances (Nonspecific plasma membrane translocases acting as efflux pumps, innate resistance, etc) - Inherent
- Alternative pathway (Bacteria use a different metabolic pathway to bypass the one targeted by the drug) - Inherent
What is selective toxicity?
Being able to attack only the target organism with a method of destruction.
What is pasteurization?
Heating liquids to a specific temperature to kill harmful bacteria
What is an autoclave?
A machine that uses high-pressure steam to sterilize items
