Virulence targeted inhibitory effect of linalool against the exclusive uropathogen <i>Proteus mirabilis</i>

<i>Proteus mirabilis</i> is one of the leading causes of catheter-associated UTIs (CAUTI) in individuals with prolonged urinary catheterization. Since, biofilm assisted antibiotic resistance is reported to complicate the treatment strategies of <i>P. mirabilis</i> infections, the present study was aimed to attenuate biofilm and virulence factor production in <i>P. mirabilis.</i> Linalool is a naturally occurring monoterpene alcohol found in a wide range of flowers and spice plants and has many biological applications. In this study, linalool exhibited concentration dependent anti-biofilm activity against crystalline biofilm of <i>P. mirabilis</i> through reduced production of the virulence enzyme urease that raises the urinary pH and drives the formation of crystals (struvite) in the biofilm. The results of q-PCR analysis unveiled the down regulation of biofilm/virulence associated genes upon linalool treatment, which was in correspondence with the <i>in vitro</i> bioassays. Thus, this study reports the feasibility of linalool acting as a promising anti-biofilm agent against <i>P. mirabilis</i> mediated CAUTI.