Skip to main content
eScholarship
Open Access Publications from the University of California

UCLA

UCLA Previously Published Works bannerUCLA

Scope and Predictive Genetic/Phenotypic Signatures of Bicarbonate (NaHCO3) Responsiveness and β-Lactam Sensitization in Methicillin-Resistant Staphylococcus aureus.

  • Author(s): Ersoy, Selvi C;
  • Otmishi, Mariam;
  • Milan, Vanessa T;
  • Li, Liang;
  • Pak, Youngju;
  • Mediavilla, Jose;
  • Chen, Liang;
  • Kreiswirth, Barry;
  • Chambers, Henry F;
  • Proctor, Richard A;
  • Xiong, Yan Q;
  • Fowler, Vance G;
  • Bayer, Arnold S
  • et al.
Abstract

Addition of sodium bicarbonate (NaHCO3) to standard antimicrobial susceptibility testing medium reveals certain methicillin-resistant Staphylococcus aureus (MRSA) strains to be highly susceptible to β-lactams. We investigated the prevalence of this phenotype (NaHCO3 responsiveness) to two β-lactams among 58 clinical MRSA bloodstream isolates. Of note, ∼75% and ∼36% of isolates displayed the NaHCO3 responsiveness phenotype to cefazolin (CFZ) and oxacillin (OXA), respectively. Neither intrinsic β-lactam MICs in standard Mueller-Hinton broth (MHB) nor population analysis profiles were predictive of this phenotype. Several genotypic markers (clonal complex 8 [CC8]; agr I and spa t008) were associated with NaHCO3 responsiveness for OXA.

Many UC-authored scholarly publications are freely available on this site because of the UC's open access policies. Let us know how this access is important for you.

Main Content
For improved accessibility of PDF content, download the file to your device.
Current View