Dispersion of Phage Integrases in Acinetobacter Baumannii Species

Dispersion of Phage Integrases in Acinetobacter baumannii strains E. Stephanie Guardado1,2, German M. Traglia2, Dr. M. Soledad Ramirez2 1Biological Sciences Dept, Cal Poly Pomona 2Instituto de Microbiolog??a y Parasitolog??a Medica (IMPaM), Facultad de Medicina (UBA??CONICET), Buenos Aires, Argentina Introduction: Research on antibiotic resistance of bacterial strains has expanded in recent years due to increasing antibiotic resistance by various bacteria, including Acinetobacter baumannii. Recent studies comparing whole genome sequences of A. baumannii isolates have demonstrated a high genomic plasticity, explaining its ability to acquire multiple antibiotic resistance determinants. This study determines the distribution of phage integrases among clinical A. baumannii strains. Methods: A total of 83 A. baumannii clinical strains were recovered from different patients, and hospitals (n=5) over several years (1982-2013). Total DNA was obtained through DNA extraction or boiling and used as the template in PCR reactions for identifying the presence of different phage integrases (AYEphgInt, ATCCphgInt, AYEphgAP22, 1656phg). The amplification of the 16sRNA was done to confirm DNA extraction and gel electrophoresis used to analyze the PCR products. Results: AYEphgInt was present in 8 of 83 strains. For ATCCphgInt and AYEphgAP22, 9 and 16 out of 83 strains were positive, respectively. Notably, the 1656phg integrase showed the highest dispersion, with 28 out of 83 strains being positive for this integrase. Conclusions: Phage integrase distribution was highest for 1656phg with the second highest distribution for AYEphgAP22, followed by ATCCphgInt and AYEphgInt. Learning more about the distribution of phage integrases in A. baumannii can help us gain insight into the antibiotic resistant mechanisms of these bacterial strains and ultimately help lead to more effective antibiotic treatments