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Susceptibility of Methicillin-Resistant Staphylococcus aureus to Five Quinazolinone Antibacterials.

ABSTRACT: The in vitro activities of five quinazolinone antibacterials, compounds Q1 to Q5, were tested against 210 strains of methicillin-resistant Staphylococcus aureus (MRSA). The MIC50/MIC90 values (in ?g/ml) were as follows: Q1, 0.5/2; Q2, 1/4; Q3, 2/4; Q4, 0.06/0.25; and Q5, 0.125/0.5. Several strains with high MIC values (from 8 to >32??g/ml) for some of these compounds exhibited amino acid changes in the penicillin-binding proteins, which are targeted by these antibacterials.

SUBMITTER: Ceballos S

PROVIDER: S-EPMC7187613 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Susceptibility of Methicillin-Resistant Staphylococcus aureus to Five Quinazolinone Antibacterials.

Ceballos Sara S Kim Choon C Qian Yuanyuan Y Mobashery Shahriar S Chang Mayland M Torres Carmen C

Antimicrobial agents and chemotherapy 20191220 1

The in vitro activities of five quinazolinone antibacterials, compounds Q1 to Q5, were tested against 210 strains of methicillin-resistant Staphylococcus aureus (MRSA). The MIC50/MIC90 values (in μg/ml) were as follows: Q1, 0.5/2; Q2, 1/4; Q3, 2/4; Q4, 0.06/0.25; and Q5, 0.125/0.5. Several strains with high MIC values (from 8 to >32 μg/ml) for some of these compounds exhibited amino acid changes in the penicillin-binding proteins, which are targeted by these a ...[more]

PMID: 31611358

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