NFKB1 and bacterial urinary tract infection: Due to TcpF's ability to negatively modulate recognition by the TLR2 receptor and NF-κB activation and the fact that tcpF not only is common among E. faecalis isolates from intestinal flora but even prevails among human UTI isolates (Figure 1), it appears that tcpF represents a recently acquired adaptive feature for E. faecalis that favors UT invasion and generally benefits mucosa colonization.