Identification of genetic recombination between Acinetobacter species based on multilocus sequence analysis

Area of Science:

• Microbiology
• Genetics
• Molecular Biology

Background:

• The Acinetobacter calcoaceticus-Acinetobacter baumannii complex comprises several closely related species.
• Accurate species identification is crucial for understanding epidemiology and treatment.

Purpose of the Study:

• To investigate potential genetic recombination within the Acinetobacter calcoaceticus-Acinetobacter baumannii complex.
• To clarify the phylogenetic relationships of specific Acinetobacter isolates.

Main Methods:

• Multilocus sequence analysis (MLSA) was performed on Acinetobacter isolates.
• Sequencing targeted housekeeping genes including 16S rRNA, gyrB, fusA, gdhB, rplB, rpoB, recA, cpn60, rpoD, and gltA.

Main Results:

• Evidence of recent genetic recombination was identified between two Acinetobacter species.
• Three isolates identified as Acinetobacter nosocomialis based on certain gene sequences (16S rRNA, gyrB, fusA, gdhB, rplB) exhibited close phylogenetic relationships with Acinetobacter genomic species 'close to 13TU' in other gene trees (rpoB, recA, cpn60, rpoD, gltA).

Conclusions:

• The findings suggest complex genetic exchange within the Acinetobacter calcoaceticus-Acinetobacter baumannii complex.
• MLSA using a broader set of genes is essential for accurate Acinetobacter species delineation and understanding their evolutionary history.