14 ] [ edit ] CbiA The CbiA family of proteins consists of various cobyrinic acid a,c-diamide synthases . These include CbiA and CbiP from Salmonella typhimurium ., [ 15 ] and CobQ from Rhodobacter capsulatus. [ 16 ] These amidases catalyse amidations to various side chains of hydrogenobyrinic acid or cobyrinic