Transcriptional analysis reveals new factors involved in the biofilm formation ability of "Acinetobacter baumannii"

Abstract

Acinetobacter baumannii is a nosocomial pathogen with a notable ability to adapt to stress conditions and develop resistance to multiple antimicrobial compounds, becoming a remarkable public health problem. Gene expression during biofilm formation in A. baumannii showed different profiles compared to planktonic cells in exponential and stationary phase of growth. We could confirm that genes A1S_1507, A1S_3168, A1S_2042, A1S_0302 y A1S_0114 coding a fimbrial protein, a pilus assembly protein, a transcriptional regulator, a hypothetical protein and an acyl-carrier protein, respectively, are involved in biofilm formation ability of A. baumannii. Furthermore, the A1S_0114 gene showed to play a role in attachment to biotic and abiotic surfaces, in virulence, and in the biosynthesis of a metabolite named as acinetin 505. Moreover, an important number of sRNAs differentially expressed in biofilm associated cells compared to planktonic cells were determined. Among them, the 13575 sRNA, highly expressed in biofilm, resulted to be involved in biofilm formation and in adherence to eukaryotic cells. In the present work, two new therapeutic targets involved in the pathogenesis of A. baumannii are described: the A1S_0114 gen and the 13573 sRNA.