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Mechanisms of action
Mechanisms of action ( 5 Questions)
A nurse is reviewing the mechanisms of action of different antimicrobial agents. The nurse understands that antibiotics that inhibit cell wall synthesis are most effective against which type of bacteria?
This is because antibiotics that inhibit cell wall synthesis are most effective against bacteria that have a thick peptidoglycan layer in their cell wall, which is characteristic of gram-positive bacteria. Peptidoglycan is a polymer of glycan and peptides that gives the cell wall its strength and rigidity. Antibiotics that inhibit cell wall synthesis, such as β-lactams and glycopeptides, prevent the formation or cross-linking of the peptidoglycan layer, resulting in cell wall defects and bacterial lysis.
Choice B is wrong because Gram-negative bacteria is wrong because gram-negative bacteria have a thin peptidoglycan layer and an outer membrane that protects them from antibiotics that target cell wall synthesis. Some gram-negative bacteria also have efflux pumps or β-lactamases that can expel or degrade these antibiotics.
Choice C is wrong because Anaerobic bacteria is wrong because anaerobic bacteria can be either gram-positive or gram-negative, and their susceptibility to antibiotics that inhibit cell wall synthesis depends on their cell wall structure and resistance mechanisms.
Choice D is wrong because Atypical bacteria is wrong because atypical bacteria are bacteria that lack a cell wall, such as Mycoplasma and Chlamydia. These bacteria are naturally resistant to antibiotics that inhibit cell wall synthesis, as they do not have a peptidoglycan layer to target.
This is because antibiotics that inhibit cell wall synthesis are most effective against bacteria that have a thick peptidoglycan layer in their cell wall, which is characteristic of gram-positive bacteria. Peptidoglycan is a polymer of glycan and peptides that gives the cell wall its strength and rigidity. Antibiotics that inhibit cell wall synthesis, such as β-lactams and glycopeptides, prevent the formation or cross-linking of the peptidoglycan layer, resulting in cell wall defects and bacterial lysis.
Choice B is wrong because Gram-negative bacteria is wrong because gram-negative bacteria have a thin peptidoglycan layer and an outer membrane that protects them from antibiotics that target cell wall synthesis. Some gram-negative bacteria also have efflux pumps or β-lactamases that can expel or degrade these antibiotics.
Choice C is wrong because Anaerobic bacteria is wrong because anaerobic bacteria can be either gram-positive or gram-negative, and their susceptibility to antibiotics that inhibit cell wall synthesis depends on their cell wall structure and resistance mechanisms.
Choice D is wrong because Atypical bacteria is wrong because atypical bacteria are bacteria that lack a cell wall, such as Mycoplasma and Chlamydia. These bacteria are naturally resistant to antibiotics that inhibit cell wall synthesis, as they do not have a peptidoglycan layer to target.