3.A.7.15.1
The nonspecific tight adherence fibril (pilus) secretion septum (Flp-1, Flp-2, TadV-RcpCAB Tad ZA-G) (Kachlany et al., 2000; Bhattacharjee et al., 2001; Haase et al., 2003; Schreiner et al., 2003; Wang and Chen, 2005; Tomich et al. 2007). The outer membrane components of the Tad (tight adherence) secreton have been identified (Clock et al. 2008). The tad locus is required for tenacious, nonspecific adherence to surfaces and formation of extremely strong biofilms. This locus is dedicated to the biogenesis of Flp pili, which are required for colonization and virulence (Perez et al. 2006). The formation of biofilms enhances gastrointestinal tolerance and intestinal adhesion of probiotics, presenting great applied potential in increasing the efficacy of probiotics (Gao et al. 2025).