INVESTIGATION OF MOLECULER MECHANISM OF QUORUM SENSING İN CLİNİCAL ACINETOBACTER ISOLATES
Project no. 380 · Status: Kapanmış · 2014
Summary
Acinetobacter baumannii is an important opportunistic human pathogen that often causes hospital infections associated with high mortality and morbidity. “Majority Detection” (Quorum Sensing- QS) is a cell-cell communication system that controls various physiological processes, such as the production of virulence factors, biofilm production and the development of antibiotic resistance. The QS system in Acinetobacter is defined as AbaI and AbaR, a two-component system homologous to the typical LuxI and LuxR system found in Gram-negative bacteria. Data on the QS system in A. baumannii is very limited. In this study, it was aimed to determine the quorum sensing signal profile of A. baumannii strains. In our study, multi-drug resistant 78 A. baumannii clinical isolate producing biofilm at different levels was used. In these isolates, the LuxI and LuxR genes were investigated by PCR and the relationship between these genes and biofilm production was evaluated. According to the PCR findings, at least one gene (LuxI or LuxR) was found in 64 (82%) of 78 strains, and more than one (LuxI and LuxR) gene was found in 60 (77%). In 14 strains (18%) all genes were negative. These results showed that A. baumannii clinical isolates produced a high QS signal. It was concluded that there was no direct interaction between the presence of the QS gene and the level of biofilm production (strong, medium and weak).