ISCR2, another vehicle for bla(VEB) gene acquisition

Area of Science:

• Microbiology
• Molecular Biology
• Genetics

Background:

• The bla(VEB-1) gene confers expanded-spectrum beta-lactamase resistance, found globally in Enterobacteriaceae and Pseudomonas aeruginosa.
• This gene is typically associated with class 1 integrons or repetitive elements, facilitating its spread.
• Acinetobacter species are significant opportunistic pathogens, and understanding their resistance mechanisms is crucial.

Purpose of the Study:

• To report the first association of the bla(VEB-1a) gene with the insertion sequence ISCR2.
• To investigate the genetic context of bla(VEB-1a) in Acinetobacter species isolates from Argentina.
• To explore the potential role of this genetic structure in the mobilization of the ESBL gene.

Main Methods:

• Genomic DNA extraction from Acinetobacter isolates.
• PCR amplification and sequencing to identify the bla(VEB-1a) gene and surrounding genetic elements.
• Bioinformatic analysis to characterize the genetic structure and its relationship with ISCR2.

Main Results:

• The bla(VEB-1a) gene was identified in six Acinetobacter species isolates.
• For the first time, the bla(VEB-1a) gene was found associated with the insertion sequence ISCR2 in these isolates.
• The identified genetic structure involving bla(VEB-1a) and ISCR2 suggests a mechanism for gene mobilization.

Conclusions:

• The association of bla(VEB-1a) with ISCR2 in Acinetobacter species represents a novel finding in antibiotic resistance research.
• This genetic arrangement likely plays a role in the dissemination of expanded-spectrum beta-lactamase resistance.
• Further studies are warranted to understand the broader implications of this discovery for antimicrobial resistance surveillance.