Rhodotorulic acid explained

Rhodotorulic acid is the smallest of the 2,5-diketopiperazine family^[1] of hydroxamate siderophores which are high-affinity chelating agents for ferric iron, produced by bacterial and fungal phytopathogens for scavenging iron from the environment.^[2] It is a tetradentate ligand, meaning it binds one iron atom in four locations (two hydroxamate and two lactam moieties), and forms Fe₂(siderophore)₃ complexes to fulfill an octahedral coordination for iron.^[3]

Rhodotorulic acid occurs in basidiomycetous yeasts^[4] and was found to retard the spore germination of the fungus Botrytis cinerea. In combination with yeast Rhodotorula glutinis it was found to be effective in the biocontrol^[5] of iprodione-resistant B. cinerea of apple wounds caused by the disease.

Notes and References

1. Borthwick AD, Da Costa NC . 2,5-Diketopiperazines in Food and Beverages: Taste and Bioactivity . Critical Reviews in Food Science and Nutrition . 57 . 4 . 718–742 . 2017 . 25629623 . 10.1080/10408398.2014.911142. 1334464 .
2. Hider RC, Kong X . Chemistry and biology of siderophores . Natural Product Reports . 27 . 5 . 637–657 . May 2010 . 20376388 . 10.1039/B906679A .
3. Book: Butler, Alison . Biological Inorganic Chemistry: Structure & Reactivity . 2007 . 151–156 . 978-1891389436.
4. Book: Metal ions in fungi . February 1994 . Marcel Dekker Inc . New York . 0-8247-9172-X . 11 . 39–98 . Van der Helm D, Winkelmann G . Winkelmann, G. . Winge, D. . Hydroxamates and Polycarboxylates as Ion Transport Agents (Siderophores) .
5. Sansone G, Rezza I, Calvente V, Benuzzi D, de Tosetti MI . Control of Botrytis cinerea strains resistant to iprodione in apple with rhodotorulic acid and yeasts . Postharvest Biology and Technology . 35 . 3 . 245–251. March 2005 . 10.1016/j.postharvbio.2004.09.005 .