RelA Mutant Enterococcus faecium with Multiantibiotic Tolerance Arising in an Immunocompromised Host.

ABSTRACT: Serious bacterial infections in immunocompromised patients require highly effective antibacterial therapy for cure, and thus, this setting may reveal novel mechanisms by which bacteria circumvent antibiotics in the absence of immune pressure. Here, an infant with leukemia developed vancomycin-resistant Enterococcus faecium (VRE) bacteremia that persisted for 26 days despite appropriate antibiotic therapy. Sequencing of 22 consecutive VRE isolates identified the emergence of a single missense mutation (L152F) in relA, which constitutively activated the stringent response, resulting in elevated baseline levels of the alarmone guanosine tetraphosphate (ppGpp). Although the mutant remained susceptible to both linezolid and daptomycin in clinical MIC testing and during planktonic growth, it dem

SUBMITTER: Honsa ES 

PROVIDER: S-EPMC5210501 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature