Itoic acid Bacillus subtilis

Condensation products of DHB (which usually is found also in the fermentation broth) with amino acids were reported, viz. with glycine ixom Bacillus subtilis (164) named subsequently itoic acid (282) with serine from Escherichia coli (261) and Klebsiella oxytoca (196) with threonine from Klebsiella oxytoca (196) and Rhizobium spp. (275, 327) with arginine from Pseudomonas stutzeri (62) with glycine and threonine from Rhizobium sp. (240) with threonine and lysine as well as with leucine and lysine from Azospirillum lipoferum (312, 320). In most cases the isolate (sometimes designated as being a siderophore) was hydrolyzed and the constituents were determined by paper chromatography. The relative amounts of the constituents, the chiralities of the amino acids and the molecular mass of the isolate have not been determined. Hence it is not known whether condensation products of the enterobactin type exist. 

Peters WJ, Warren RAJ (1968) Itoic Acid Synthesis in Bacillus subtilis. J Bacteriol 95 360... 

A number of catechols of lower molecular weight, which have siderophoric properties, have been isolated. Examples are shown in Figure 46. All organisms synthesizing enterobactin also form 2,3-dihydroxybenzoylserine, while a number of related species are also present. One of these, itoic acid, from Bacillus subtilis was the first phenolate siderophoric ligand to be isolated.1185... 

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