Details:

Alternative Title:
Emerg Infect Dis
Personal Author:
Johnson, Crystal N. ; Briles, David E. ; Benjamin, William H. ; Hollingshead, Susan K. ; Waites, Ken B.
Johnson, Crystal N. ; Briles, David E. ; Benjamin, William H. ; Hollingshead, Susan K. ; Waites, Ken B. Less -
Description:
Fluoroquinolone resistance in Streptococcus pneumoniae is primarily mediated by point mutations in the quinolone resistance-determining regions of gyrA and parC. Antimicrobial resistance mutations in housekeeping genes often decrease fitness of microorganisms. To investigate the fitness of quinolone-resistant S. pneumoniae (QRSP), the relative growth efficiencies of 2 isogenic QRSP double mutants were compared with that of their fluoroquinolone-susceptible parent, EF3030, by using murine nasopharyngeal colonization and pneumonia models. Strains containing the GyrA: Ser81Phe, ParC: Ser79Phe double mutations, which are frequently seen in clinical QRSP, competed poorly with EF3030 in competitive colonization or competitive lung infections. However, they efficiently produced lung infection even in the absence of EF3030. The strain containing the GyrA: Ser81Phe, ParC: Ser79Tyr double mutations, which is seen more frequently in laboratory-derived QRSP than in clinical QRSP, demonstrated reduced nasal colonization in competitive or noncompetitive lung infections. However, the strain was equally able to cause competitive or noncompetitive lung infections as well as EF3030.
Subject:
[+]
Animals
Anti-Infective Agents
Antimicrobial Resistance
Colony Count, Microbial
DNA Gyrase
DNA Topoisomerase IV
Drug Resistance, Bacterial
Fitness
Fluoroquinolone
Fluoroquinolones
Humans
Keywords: Animal Model
Lung
Mice
Mutation
Nasopharyngeal Carriage
Nasopharynx
Pneumonia
Pneumonia, Pneumococcal
Research
Streptococcus Pneumoniae

Source:
Emerg Infect Dis. 11(6):814-820.
Document Type:
Journal Article
Collection(s):
Emerging Infectious Diseases
Main Document Checksum:
[+]
urn:sha256:44aaf28b583ecc596b34f1a53f73147607fd2b9698cbdb756e0b3031b646bec0
File Type:

Supporting Files

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