Oral cavities of healthy infants harbour high proportions of Streptococcus salivarius strains with phenotypic and genotypic resistance to multiple classes of antibiotics.
J Med Microbiol
; 65(12): 1456-1464, 2016 Dec.
Article
em En
| MEDLINE
| ID: mdl-27902365
Emerging antibiotic resistance in the oropharyngeal microbiota, of which Streptococcus salivarius is a prominent species, represents a challenge for treating paediatric populations. In this study, we investigated the role of Streptococcussalivarius as a reservoir for antibiotic resistance genes (ARG) in the oral microbiota by analysing 95 Streptococcussalivarius isolates from 22 healthy infants (2-16 months of age). MICs of penicillin G, amoxicillin, erythromycin, tetracycline, doxycycline and streptomycin were determined. ARG profiles were assessed in a subset of 21 strains by next-generation sequencing of genomes, followed by searches of assembled reads against the Comprehensive Antibiotic Resistance Database. Strains resistant to erythromycin, penicillins and tetracyclines were isolated from 83.3, 33.3 and 16.6 %, respectively, of infants aged 2 to 8 months with no prior antibiotic treatment. These percentages were100.0, 66.6 and 50.0 %, by 13 to 16 months of age. ARG or polymorphisms associated with antibiotic resistance were the most prevalent and involved genes for macrolide efflux (mel, mefA/E and macB), ribosomal protection [erm(B), tet(M) and tet(O)] and ß-lactamase-like proteins. Phylogenetically related strains showing multidrug-resistant phenotypes harboured multidrug efflux ARG. Polymorphic genes associated with antibiotic resistance to drugs affecting DNA replication, folate synthesis, RNA/protein synthesis and regulators of antibiotic stress responses were detected. These data imply that Streptococcussalivarius strains established during maturation of the oral microbiota harbour a diverse array of functional ARG, even in the absence of antibiotic selective pressures, highlighting a potential role for this species in shaping antibiotic susceptibility profiles of oropharyngeal communities.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Farmacorresistência Bacteriana Múltipla
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Streptococcus salivarius
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Antibacterianos
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Boca
Limite:
Female
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Humans
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Infant
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Male
Idioma:
En
Revista:
J Med Microbiol
Ano de publicação:
2016
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Reino Unido