Exploitation of a Bacteriophage Receptor-Binding Protein as a Superior Biorecognition Molecule.

is a Gram-negative bacterium that has become one of the leading causes of life-threatening healthcare-associated infections (HAIs), including pneumonia and sepsis. Moreover, due to its increasingly antibiotic resistance, has been declared a global top priority concern. The problem of infections is due, in part, to the inability to detect this pathogen rapidly and accurately and thus to treat patients within the early stages of infections. The success in bacterial detection is greatly dictated by the biorecognition molecule used, with the current diagnostic tools relying on expensive probes often lacking specificity and/or sensitivity. (Bacterio)phage receptor-binding proteins (RBPs) are responsible for the recognition and adsorption of phages to specific bacterial host receptors and thus present high potential as biorecognition molecules. In this study, we report the identification and characterization of a novel RBP from the phage KpnM6E1 that presents high specificity against the target bacteria and high sensitivity (80%) to recognize strains. Moreover, adsorption studies validated the role of 86 in the attachment to bacterial receptors, as it highly inhibits (86%) phage adsorption to its host. Overall, in this study, we unravel the role and potential of a novel phage RBP as a powerful tool to be used coupled with analytical techniques or biosensing platforms for the diagnosis of infections.