FBP_C is a family from the C terminal end of fibronectin-binding proteins. It forms an extended four-cysteine zinc-finger with a unique structural fold. Fibronectin-binding proteins bind to elongation factor G - EF-G, which is mediated by the zinc-finger binding to the C-terminus of EF-G [1]. FBPs release ribosomes by competing with them for EF-G [2].

1: Ribosome clearance by FusB-type proteins mediates resistance to the antibiotic fusidic acid. Cox G, Thompson GS, Jenkins HT, Peske F, Savelsbergh A, Rodnina MV, Wintermeyer W, Homans SW, Edwards TA, O'Neill AJ; Proc Natl Acad Sci U S A. 2012;109:2102-2107. PMID:22308410

2: Structure and function of FusB: an elongation factor G-binding fusidic acid resistance protein active in ribosomal translocation and recycling. Guo X, Peisker K, Backbro K, Chen Y, Koripella RK, Mandava CS, Sanyal S, Selmer M; Open Biol. 2012;2:120016. PMID:22645663