English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/185858
Share/Impact:
Statistics
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:

Title

A gene homologous to rRNA methylase genes confers erythromycin and clindamycin resistance in Bifidobacterium breve

AuthorsMartínez Álvarez, Noelia ; Luque, Roberto; Milani, Christian; Ventura, Marco; Bañuelos, Oscar; Margolles Barros, Abelardo
KeywordsBifidobacterium
Bifidobacterium breve
Clindamycin resistance
Erythromycin resistance
Microbiota
Probiotics
Issue DateMay-2018
PublisherAmerican Society for Microbiology
CitationApplied and Environmental Microbiology 84(10): e02888-17 (2017)
AbstractBifidobacteria are mutualistic intestinal bacteria, and their presence in the human gut has been associated with health-promoting activities. The presence of antibiotic resistance genes in this genus is controversial, since, although bifidobacteria are nonpathogenic microorganisms, they could serve as reservoirs of resistance determinants for intestinal pathogens. However, until now, few antibiotic resistance determinants have been functionally characterized in this genus. In this work, we show that Bifidobacterium breve CECT7263 displays atypical resistance to erythromycin and clindamycin. In order to delimit the genomic region responsible for the observed resistance phenotype, a library of genomic DNA was constructed and a fragment of 5.8 kb containing a gene homologous to rRNA methylase genes was able to confer erythromycin resistance in Escherichia coli. This genomic region seems to be very uncommon, and homologs of the gene have been detected in only one strain of Bifidobacterium longum and two other strains of B. breve. In this context, analysis of shotgun metagenomics data sets revealed that the gene is also uncommon in the microbiomes of adults and infants. The structural gene and its upstream region were cloned into a B. breve-sensitive strain, which became resistant after acquiring the genetic material. In vitro conjugation experiments did not allow us to detect gene transfer to other recipients. Nevertheless, prediction of genes potentially acquired through horizontal gene transfer events revealed that the gene is located in a putative genomic island. IMPORTANCE Bifidobacterium breve is a very common human intestinal bacterium. Often described as a pioneer microorganism in the establishment of early-life intestinal microbiota, its presence has been associated with several beneficial effects for the host, including immune stimulation and protection against infections. Therefore, some strains of this species are considered probiotics. In relation to this, because probiotic bacteria are used for human and animal consumption, one of the safety concerns over these bacteria is the presence of antibiotic resistance genes, since the human gut is a densely populated habitat that could favor the transfer of genetic material to potential pathogens. In this study, we analyzed the genetic basis responsible for the erythromycin and clindamycin resistance phenotype of B. breve CECT7263. We were able to identify and characterize a novel gene homologous to rRNA methylase genes which confers erythromycin and clindamycin resistance. This gene seems to be very uncommon in other bifidobacteria and in the gut microbiomes of both adults and infants. Even though conjugation experiments showed the absence of transferability under in vitro conditions, it has been predicted to be located in a putative genomic island recently acquired by specific bifidobacterial strains.
Publisher version (URL)http://dx.doi.org/10.1128/AEM.02888-17
URIhttp://hdl.handle.net/10261/185858
DOI10.1128/AEM.02888-17
ISSN0099-2240
E-ISSN1098-5336
Appears in Collections:(IPLA) Artículos
Files in This Item:
File Description SizeFormat 
accesoRestringido.pdf15,35 kBAdobe PDFThumbnail
View/Open
Show full item record
Review this work
 

Related articles:


WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.