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Updated: Feb 22, 2026
09:37
Screening Foodstuffs for Class 1 Integrons and Gene Cassettes
Published on: June 19, 2015
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Study on the excision and integration mediated by class 1 integron in Streptococcus pneumoniae
Qun Lin1, Pusheng Xu2, Jiaowu Li1
1Department of Respiratory, The Affiliated Shunde Hospital of Guangzhou Medical University, Foshan 528315, China.
Microbial Pathogenesis
|September 20, 2017
Summary
Integrons, mobile genetic elements, facilitate antibiotic resistance gene transfer in Gram-positive bacteria. This study confirms integron excision and integration in Streptococcus pneumoniae, highlighting their role in spreading antibiotic resistance.
Area of Science:
- Microbiology
- Molecular Biology
- Genetics
Background:
- Integrons are mobile genetic elements known to acquire and disseminate antibiotic resistance genes.
- Gram-positive bacteria, particularly Streptococcus pneumoniae, are significant reservoirs of antibiotic resistance.
Purpose of the Study:
- To investigate the excision and integration capabilities of class 1 integrons in Streptococcus pneumoniae.
- To explore the role of integrons in the acquisition of exogenous antibiotic resistance genes in Gram-positive bacteria.
Main Methods:
- Utilized eight different plasmids for conjugation experiments with Streptococcus pneumoniae.
- Confirmed integron excision and integration using att site and gene cassette analysis.
- Employed Polymerase Chain Reaction (PCR) amplification for verification.
Main Results:
- Successfully observed the excision of class 1 integrons within Streptococcus pneumoniae.
- Demonstrated the integration of exogenous antibiotic resistance genes mediated by class 1 integrons.
- Confirmed these processes through specific molecular assays and PCR.
Conclusions:
- Class 1 integrons are active in mediating gene cassette excision and integration in Streptococcus pneumoniae.
- Integrons represent a significant mechanism for the spread of antibiotic resistance in Gram-positive bacteria.
- Further attention should be given to integrons as key drivers of antibiotic resistance in Streptococcus species.
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