Involved in the biosynthesis of the siderophore staphyloferrin A. Catalyzes the ATP-dependent condensation of a citryl-D-ornithine intermediate, produced by SfnaD, and citrate to form staphyloferrin A. ATP + citrate + N(5)-[(S)-citryl]-D-ornithine = AMP + diphosphate + H(+) + staphyloferrin A Siderophore biosynthesis. Belongs to the IucA/IucC family.