Mugineic-acid 3-dioxygenase explained

Mugineic-acid 3-dioxygenase
Ec Number:	1.14.11.25

Mugineic-acid 3-dioxygenase (IDS2) is an enzyme with systematic name mugineic acid,2-oxoglutarate:oxygen oxidoreductase (3-hydroxylating).^{[1] [2]} This enzyme catalyses the following chemical reaction

(1) mugineic acid + 2-oxoglutarate + O₂

\rightleftharpoons 3-epihydroxymugineic acid + succinate + CO₂

(2) 2'-deoxymugineic acid + 2-oxoglutarate + O2

\rightleftharpoons 3-epihydroxy-2'-deoxymugineic acid + succinate + CO₂

Mugineic-acid 3-dioxygenase contains iron(II).Mugineic acid is an amino acid excreted by some graminaceous (grassy) plants under conditions of iron deficiency as part of a strategy of solubilizing Fe from the root environment for uptake by the plant. Mugineic acid is closely related to its biochemical precursor, nicotianamine, and to a number of other compounds that also have been identified as phytosiderophores in graminaceous plants: 3-hydroxymugineic acid, 2'-deoxymugineic acid, avenic acid, and distichonic acid.The effectiveness of mugineic acid under iron-deficient conditions is dependent not only upon the iron chelating properties of the Fe-mugineic acid complex itself but also upon the presence of a plant membrane carrier that recognizes and absorbs the Fe-mugineic acid complex almost exclusively.^[3]

Notes and References

1. Nakanishi H, Yamaguchi H, Sasakuma T, Nishizawa NK, Mori S . Two dioxygenase genes, Ids3 and Ids2, from Hordeum vulgare are involved in the biosynthesis of mugineic acid family phytosiderophores . Plant Molecular Biology . 44 . 2 . 199–207 . September 2000 . 11117263 . 10.1023/A:1006491521586 . 26139505 .
2. Okumura N, Nishizawa NK, Umehara Y, Ohata T, Nakanishi H, Yamaguchi T, Chino M, Mori S . A dioxygenase gene (Ids2) expressed under iron deficiency conditions in the roots of Hordeum vulgare . Plant Molecular Biology . 25 . 4 . 705–19 . July 1994 . 8061321 . 10.1007/BF00029608 . 20143807 .
3. Web site: Mugineic acid, a phytosiderophore . 2013-11-04 . 2011-08-28 . https://web.archive.org/web/20110828160139/http://www.soils.wisc.edu/~barak/images/mug_frm.htm . dead .