3.A.15.4.2
The tri-component complex including (1) EbsA of 125 aas, homologs of which are highly conserved and widespread in diverse cyanobacteria but are not found outside this clade; (2) PilB, a 666 aa type IV fimbrial biogenesis protein, and (3) Hfq, a 70 aa host factor-1 protein. The tripartite complex of EbsA, Hfq, and the ATPase homolog PilB (formerly called T2SE) are all three required for the assembly of the hairlike type IV pili (T4P) appendages, for DNA competence, and for exoproteome formation in addition to its role in biofilm self-suppression (Yegorov et al. 2021).