Siderophores citrate-hydroxamate

Siderophores with citrate-hydroxamate structures (schizokinen, arthrobactin and aerobactin) are synthesized by enteric bacilli and Arthrobacter spp. Their structures are shown in Figure 48. 

Fig. 15. Citrate siderophores with two hydroxamic acid units...

Legionella pneumophila produces a siderophore named legiobactin, which shows no catecholate or hydroxamate reactions (206). Enzymatic studies suggest a citrate structure in agreement with the data obtained by mass spectrometry (molecular mass ca. 350 Da) and NMR (three carbonyl and ten aliphatic C atoms). It is not clear yet as to whether legiobactin is essential for the iron acquisition in the aqueous habitat of the bacterium or during lung infection (2, 65). 

Siderophores isolated from marine microorganisms contain iron-binding moieties similar to their terrestrial counterparts catecholates, hydroxamates, and a-hydroxycarboxylates. Isolated hydroxamates include Ferrioxamine from Vibrio strain BLI-4, the aquachelins " from Halo-monas aquamaria, and the marinobactins " from Marinobacter species DS40M6 and DS40M8. Petrobactin from Marinobacter hydrocarbonoclasticus includes both catecholate and citrate... 

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