Does daptomycin inhibit cell wall synthesis?
We found that daptomycin causes a gradual decrease in membrane potential but does not form discrete membrane pores. Although we found no evidence for altered membrane curvature, we confirmed that daptomycin inhibits cell wall synthesis.
What is the mechanism of action of daptomycin?
Mechanism of action The aggregation of daptomycin alters the curvature of the membrane, which creates holes that leak ions. This causes rapid depolarization, resulting in a loss of membrane potential leading to inhibition of protein, DNA, and RNA synthesis, which results in bacterial cell death.
Why does daptomycin not affect gram negative bacteria?
Daptomycin has rapid concentration-dependent bactericidal activity against most gram-positive pathogens, including those with multidrug resistance [2, 3, 5, 7]. It is not active against gram-negative organisms because of its inability to penetrate the outer membrane of the bacteria [2, 3, 5].
Does daptomycin act on cell membrane?
Our results support a mechanism for daptomycin with a primary effect on cell membranes that in turn redirects the localization of proteins involved in cell division and cell wall synthesis, causing dramatic cell wall and membrane defects, which may ultimately lead to a breach in the cell membrane and cell death.
What is the cellular target of daptomycin?
bacterial cell membranes
Daptomycin is a lipopeptide that targets bacterial cell membranes and has been successfully used to treat skin and soft tissue infections caused by Gram-positive bacteria, including E. faecalis species.
What is the cellular target of daptomycin quizlet?
What is the cellular target of daptomycin? Daptomycin is a lipopeptide directed against gram-positive bacteria, acting to disrupt multiple aspect of membrane function.
How is daptomycin produced?
Daptomycin is produced by submerged fermentation of Streptomyces roseosporus, in particular strains NRRL 11379 (ATCC 31568) and NRRL 15998, as well as any mutants, variants and recombinants thereof. The production of Daptomycin in submerged culture was first disclosed in U.S. Pat.
Is daptomycin concentration or time dependent?
Daptomycin is the first member of the novel cyclical- lipopeptide class, which provides rapid, concentration-dependent bactericidal activity against a broad range of gram-positive pathogens, including methicillin-resistant Staphylococcus aureus (MRSA) (2, 6, 9, 10).
Is daptomycin bacteriostatic or bactericidal?
Daptomycin is a lipopeptide antibiotic with a distinct mechanism of action that targets the cytoplasmic membrane of gram-positive organisms, including Staphylococcus aureus. Daptomycin is rapidly bactericidal against exponentially growing bacteria (a 3-log reduction in 60 min).
What is a major side effect of tetracyclines?
Nausea, vomiting, diarrhea, loss of appetite, mouth sores, black hairy tongue, sore throat, dizziness, headache, or rectal discomfort may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.
How is daptomycin metabolized?
Daptomycin is primarily renally excreted, with the majority of the drug remaining intact in the urine. Since daptomycin is excreted through the kidneys, the dosing interval is increased to every 48 h in patients with severe renal impairment defined as a creatinine clearance of <30 mL/min.
Which two of the following are targets of antibacterial drugs that inhibit nucleic acid synthesis?
The nucleic acid synthesis inhibitors rifamycins and fluoroquinolones target bacterial RNA transcription and DNA replication, respectively.