Antibiotics and Antibiotic Resistance Flashcards
Antibiotics are produced by _____
bacteria/fungi
Antibiotics most effective against _____
bacterial infections
Problem with Antibiotics (2)
1) drug companies not interested developing new
2) bacterial resistance
Misuse of antibiotics (5)
- empiric use
- broad-spectrum
- viral infections
- not complete course
- antibiotics in animal feeds (resistance)
Minimum Inhibitory Concentration
- measures?
- culture tubes vary?
- it is ___ concentration that ___ growth?
- measures antibiotic activity
- vary concentration
- lowest, inhibits
What 5 bacterial components do antibiotics target?
1) Cell Wall Synthesis
2) Protein Synthesis
3) DNA/RNA Synthesis
4) Folate Synthesis
5) Cell Membrane Alteration
B Lactam Antibiotics
- inhibit ___?
- bind ____? inhibits___?
- cell wall synthesis
- Penicillin-Binding Proteins
- inhibits cross-link
What destroys B Lactam Ring?
B lactamase
Methicillin-Chem modified penicillin
- not cleaved by __?
- different PBP2a?
- B lactamase
- doesn’t bind methicillin
Vancomycin
- inhibit?
- gram __?
- binds __, @___? inhibits?
- inhibit cell wall synthesis
- gram POSITIVE
- binds peptide linkage
- at D-Ala-D-Ala
- inhibits transpeptidation
Resistance Genes to Vancomycin
- name?
- change peptide to?
- van genes
- D-Ala-D-Lac
Bacterial Strategies to Antibiotics (4)
1) Prevent Antibiotic Entry (cell envelope)
2) Antibiotic modification (B lactamase)
3) Efflux of Antibiotic
4) Alteration Antibiotic target (PBPs)
- mechanisms of antibiotic resistance _____ encoded
- encoded on _____
- genetically
- mobile genetic elements
Horizontal Gene Transfer (3)
1) Bacterial Transformation (free DNA)
2) Bacterial Transduction (DNA move via virus)
3) Bacterial Conjugation
(Gene move via plasmid)
Antibiotic Threats
- Klebsiella pneumoniae
- Clostridia
Klebsiella pneumoniae
- Gram __?
- Produces?
- NDM-1 Antibiotics are ___ resistant?
- Gram NEGATIVE
- capsule
- B lactamase
Clostridia
- Gram __?
- Forms __?
- O2?
- Gram POSITIVE
- endospores
- anaerobe
Clostridioides difficile
- asymptomatic carrier state in ______
- ____ difficult eradicate
- transmission?
- large intestine
- endospores
- fecal-oral transmission
C.diff produce ___?
- _ Domain? Inactivates?
- _ Domain?
- A-B toxins
- A domain = active (enzymatic activity)
- inactivates key regulatory proteins of host cells
- B domain = bind + uptake by host
Pseduomembranous colitis
- ____ condition
- ____ receiving antibiotics
- endoscopy shows?
- endospores ____, overgrowth of C.diff –> ____ —> _____
- inflammatory
- AFTER
- lesions
- germinate, exotoxins, inflammation
Treatment of C.diff
- problem?
- ___ transplantation?
- cycle
- kill some, remain germinate
- Fecal Microbiota (enter new good bacteria into microbiome)
