This domain is found in the protein SsfX3 from Streptomyces sp. and in similar bacterial proteins. SsfX3 is an acyltransferase involved in the biosynthesis of the anticancer natural product SF2575. This protein is organised into two distinct domains: an N-terminal beta-sandwich (this entry) and a C-terminal catalytic domain (GDSL-like Lipase/Acylhydrolase domain, Pfam:PF13472). This domain resembles a carbohydrate-binding module (CBM) domain and is critical for substrate binding [1].

1: Structural and biochemical characterization of the salicylyl-acyltranferase SsfX3 from a tetracycline biosynthetic pathway. Pickens LB, Sawaya MR, Rasool H, Pashkov I, Yeates TO, Tang Y; J Biol Chem. 2011;286:41539-41551. PMID:21965680