The Gram-negative bacterium is the causative agent for enteric red mouth disease in salmonids. The genome of YRB contains a biosynthetic gene cluster encoding the biosynthesis of catechol siderophores that are diastereomeric with the known vanchrobactin class of siderophores, (DHBArgSer). Ruckerbactin (), produced by YRB, was found to be the linear tris-l-serine ester composed of l-arginine and 2,3-dihydroxybenzoic acid, (DHBArgSer). The biscatechol, (DHBArgSer) (), and monocatechol, DHBArgSer (), compounds were also isolated and characterized. The macrolactone of ruckerbactin was not detected. The presence of Arg in ruckerbactin makes it the diastereomer of trivanchrobactin with Arg. The electronic circular dichroism spectra of Fe(III)-ruckerbactin and Fe(III)-trivanchrobactin reveal the opposite enantiomeric configurations at the Fe(III) sites. Fe(III)-ruckerbactin adopts the Δ configuration, and Fe(III)-trivanchrobactin adopts the Λ configuration. YRB was also found to produce the antimicrobial agent holomycin ().