The fibronectin-binding proteins of Staphylococcus aureus may promote mammary gland colonization in a lactating mouse model of mastitis.

The fibronectin-binding proteins (FnBPs) of Staphylococcus aureus are believed to be implicated in the pathogen's adherence to and colonization of bovine mammary glands, thus leading to infectious mastitis. In vitro studies have shown that FnBPs help the adhesion of the pathogen to bovine mammary epithelial cells. However, the importance of FnBPs for the infection of mammary glands has never been directly established in vivo. In this study with a mouse model of mastitis, the presence of FnBPs on the surface of S. aureus increased the capacity of the bacterium to colonize mammary glands under suckling pressure compared to that of a mutant lacking FnBPs.