J. Ma, T. Shinada, Chitose Matsuda
Jul 14, 1995
Citations
3
Influential Citations
134
Citations
Quality indicators
Journal
The Journal of Biological Chemistry
Abstract
The biosynthesis of 2′-deoxymugineic acid, a key phytosiderophore, was examined in association with the putative methionine recycling pathway in the roots of wheat using labeling experiments and structural analysis. Feeding with D-[1-C]ribose did not result in C enrichment of 2′-deoxymugineic acid, while D-[2-C]ribose resulted in C enrichment at the C-4″, −1, −4′ positions, and D-[5-C]ribose did in C-1′, −4, and −1″ positions of 2′-deoxymugineic acid, respectively. Furthermore, two isotope-labeled intermediates of the methionine recycling pathway, 5-[5-2H2]methylthioribose and 2-[1-C]keto-4-methylthiobutyric acid, were synthesized, and their incorporation into 2′-deoxymugineic acids was investigated. Six deuterium atoms at the C-4, −1′, and −1″ positions of 2′-deoxymugineic acid were observed after feeding with 5-[5-2H2]methylthioribose. Feeding with 2-[1-C]keto-4-methylthiobutyric acid yielded 2′-deoxymugineic acid enriched with C at the C-4′, −1, and −4″ positions. These results demonstrated for the first time that the biosynthesis of 2′-deoxymugineic acid is associated with the methionine recycling pathway. This association system functions to recycle methionine required for continued synthesis of mugineic acids in the roots of gramineous plants.