Prediction of nuclear targeting proteins with nuclear localization signals in Staphylococcus aureus and nuclear targeting of β-lactamase in host cells

Nuclear targeting of bacterial proteins in host cells and subsequent interaction with nuclear molecules are an emerging pathogenic mechanism of bacteria. In this study, we predicted the nuclear targeting proteins with nuclear localization signals (NLSs) in Staphylococcus aureus using bioinformatic analysis. A total of 51 proteins of S. aureus, comprising of 24 functional and 27 hypothetical proteins, were predicted to carry putative NLSs. Among them, β-lactamase and MsrR proteins with the putative NLSs were selected to determine the nuclear targeting in host cells. Fusion proteins of BlaZ-green fluorescent protein (GFP) were evenly distributed in the nuclei of host cells and subsequently induced host cell death. However, fusion proteins of MsrR-GFP were not localized in the nuclei of host cells In conclusion, screening of nuclear targeting proteins with NLSs and determination of their pathology in host cells may open up the new field of S. aureus pathogenesis.