Identification of a metagenomic gene cluster containing a new class A beta‐lactamase and toxin‐antitoxin systems
Autor: | Pierre Cornelis, Laurence Van Melderen, Josselin Bodilis, Ken Vercammen, Nathalie Goeders, Tamara Garcia-Armisen |
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Přispěvatelé: | Microbiology, Department of Bio-engineering Sciences |
Rok vydání: | 2013 |
Předmět: |
Transposable element
Antibiotic resistance Bacterial Toxins Molecular Sequence Data Restriction Mapping Biology Microbiology beta-Lactam Resistance beta-Lactamases Restriction map Belgium Rivers Gene cluster Escherichia coli Antibiotic resistance metagenomic DNA toxin-anti Cloning Molecular metagenomic DNA Gene Original Research Genetics Inverse polymerase chain reaction toxin–antitoxin systems Sequence Analysis DNA β-lactamase Toxin-antitoxin systems Metagenomic DNA Molecular biology Fosmid Mutagenesis Insertional Open reading frame Multigene Family DNA Transposable Elements Metagenome Transposon mutagenesis Metagenomics Microbiologie et protistologie [bacteriol.virolog.mycolog.] |
Zdroj: | MicrobiologyOpen, 2 (4 MicrobiologyOpen |
ISSN: | 2045-8827 |
DOI: | 10.1002/mbo3.104 |
Popis: | Several reports mention the presence of antibiotic resistance genes in natural and polluted environments, but many studies are based on their detection via polymerase chain reaction (PCR amplification of known genes and not on an activity screening. We constructed a metagenomic fosmid bank from DNA isolated from a polluted river in Brussels, Belgium, the Zenne. A total of 120,000 clones were pooled and plated directly on solid media containing different antibiotics. Several clones were isolated which could grow in the presence of ampicillin. The DNA from several clones was extracted and subjected to restriction analysis and, based on their restriction pattern, two different clones were found. One of the clones was selected for further study as it showed a higher level of resistance to different β-lactams antibiotics (ticarcilline and ceftazidime). To find out which gene is responsible for the resistance, an in vitro transposon mutagenesis was performed and clones having lost the resistance phenotype were analyzed via inverse PCR amplification. Several clones had an insert in a gene encoding a new type of β-lactamase. The amplified fosmid DNA was fully sequenced revealing an insert of 41 kb containing 39 open reading frames (ORFs). Transposon insertions inactivating the resistance to β-lactams were also found in the ORF upstream of the blaA gene, encoding an aminotransferase, suggesting a polar effect on the transcription of the gene downstream. In addition, other genes were found such as histidine biosynthesis genes, which were found to be scattered on the insert, a relA/spoT gene, and genes belonging to type II toxin-antitoxin system. This predicted system was experimentally validated in Escherichia coli using an inducible expression system. Journal Article Research Support, Non-U.S. Gov't SCOPUS: ar.j info:eu-repo/semantics/published |
Databáze: | OpenAIRE |
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