TI-2 Antimicrobial mechanisms of resistance Flashcards
What is the primary reason microbes produce antibiotics?
To gain a competitive advantage over neighboring microbes.
Why has antibiotic resistance become more pronounced in recent years?
Due to the widespread use and manufacturing of antibiotics.
How often do mutations occur in bacterial populations?
1 in every 10^6 to 10^8 cells.
What is the consequence of treating a sensitive bacterial population with antibiotics?
It selects for and increases the number of resistant bacteria.
What factors promote antibiotic resistance in bacterial populations?
Overuse, overprescribing, aging populations, and use in farming.
Which bacterial pathogens are currently of particular concern due to multi-drug resistance?
Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, MRSA, and multi-drug resistant M. tuberculosis.
What are the two main types of antimicrobial resistance?
Intrinsic resistance and acquired resistance.
What defines intrinsic resistance in bacteria?
A natural resistance to an antimicrobial shared by all strains of a species.
How does acquired resistance differ from intrinsic resistance
Acquired resistance develops in some bacteria of a species, not all.
What are the two types of acquired resistance
Genetic (irreversible) and phenotypic (reversible).
What is phenotypic resistance associated with?
Specific growth conditions, such as growth in biofilms
How can bacteria acquire genetic resistance?
Through mutations in chromosomal DNA or acquiring new DNA, such as plasmids.
What is the significance of plasmids in antibiotic resistance?
They can carry multiple antibiotic resistance genes and facilitate the rapid spread of resistance.
What role do beta-lactamases play in antibiotic resistance?
They hydrolyze beta-lactam antibiotics, rendering them inactive.
What is the function of clavulanic acid when combined with amoxicillin?
It acts as a beta-lactamase inhibitor, extending the effectiveness of amoxicillin.
