Biosynthesis of 5-alkylresorcinol in rice: incorporation of a putative fatty acid unit in the 5-alkylresorcinol carbon chain.
A previously unspecified "starter" unit in the predicted biosynthesis pathway of 5-alkylresorcinols has now identified as a fatty acid or its equivalent, using an efficient 5-alkylresorcinol production system of etiolated rice seedlings. Feeding saturated, odd-carbon fatty acid ester substrates from C11 to C19 specifically and markedly increased the amount of the corresponding 5-alkylresorcinol homologs with even-carbon chains that are shorter by one carbon than those of the supplied fatty acids. The amount of these homologs depended on substrate concentration. Some of the homologs whose amounts increased had linear carbon chains and the dodecyl homolog was shown to be 5-n-dodecylresorcinol. Moreover, the 13C label in the dodecyl homolog that was biosynthesized from the [1-13C]tridecanoate substrate was localized on the C-5 carbon of the resorcinol ring. These results obviously show that the fatty acid unit acts as a direct precursor and forms the side-chain moiety of 5-n-alkylresorcinol via the predicted biosynthesis pathway.
Suzuki
Yoshikatsu
Y
RIKEN Institute (The Institute of Physical and Chemical Research), 2-1 Hirosawa, 351-0198 Wako-shi, Saitama, Japan. yoshi@postman.riken.go.jp
Kurano
Minoru
M
Esumi
Yasuaki
Y
Yamaguchi
Isamu
I
Doi
Yoshiharu
Y
D000478:Alkylation; D002247:Carbon Isotopes; D002851:Chromatography, High Pressure Liquid; D003652:Decanoic Acids / Q000737:chemistry / Q000378:metabolism; D005227:Fatty Acids / Q000032:analysis / Q000378:metabolism*; D005230:Fatty Acids, Nonesterified / Q000737:chemistry / Q000378:metabolism; D008401:Gas Chromatography-Mass Spectrometry; D012275:Oryza / Q000378:metabolism*; D010937:Plant Growth Regulators / Q000378:metabolism; D012118:Resorcinols / Q000737:chemistry / Q000378:metabolism*; D036226:Seedlings / Q000378:metabolism; D013057:Spectrum Analysis
D002247:Carbon Isotopes; D003652:Decanoic Acids; D005227:Fatty Acids; D005230:Fatty Acids, Nonesterified; D010937:Plant Growth Regulators; D012118:Resorcinols; C031071:decanoic acid