The in vitro biosynthesis of dhurrin, the cyanogenic glycoside of Sorghum bicolor.
نویسندگان
چکیده
A microsomal fraction from seedlings of Sorghum bicolor (Linn) Moench has been shown to catalyze the conversion of L-tyrosine to p-hydroxymandelonitrile via p-hydroxyphenylacetaldoxime. This transformation is consistent with the general pathway for cyanogenic glycoside biosynthesis proposed on the basis of in vivo experiments. When the microsomal fraction was combined with a protein fraction from the soluble portion of the cell and uridine diphosphate glucose, it was possible to demonstrate the synthesis of the cyanogenic glycoside dhurrin from L-tyrosine.
منابع مشابه
The Biosynthesis of Cyanogenic Glucosides in Higher Plants IDENTIFICATION OF THREE HYDROXYLATION STEPS IN THE BIOSYNTHESIS OF DHURRIN IN SORGHUM BICOLOR (L.) MOENCH AND THE INVOLVEMENT
s of the 11th Federation of European Biochemical Societies Meeting, Copenhagen, August 14-19, 1977, Abstr. LB-400. by gest on O cber 8, 2017 hp://w w w .jb.org/ D ow nladed from 21116 Biosynthesis of the Cyanogenic Glucoside Dhurrin in Sorghum FIG. 1. Biosynthetic pathway for tyrosine-derived cyanogenic glucoside dhurrin from S. bicolor. The double arrows indicate potential multistep conversion...
متن کاملThe biosynthetic gene cluster for the cyanogenic glucoside dhurrin in Sorghum bicolor contains its co-expressed vacuolar MATE transporter
Genomic gene clusters for the biosynthesis of chemical defence compounds are increasingly identified in plant genomes. We previously reported the independent evolution of biosynthetic gene clusters for cyanogenic glucoside biosynthesis in three plant lineages. Here we report that the gene cluster for the cyanogenic glucoside dhurrin in Sorghum bicolor additionally contains a gene, SbMATE2, enco...
متن کاملStereochemical aspects of the biosynthesis of the epimeric cyanogenic glucosides dhurrin and taxiphyllin.
Dhurrin, I ((S)-p-hydroxymandelonitrile-beta-D-glucopyranoside), and taxiphyllin, II (the (R) epimer), occur in the genera Sorghum and Taxus, respectively. Both derive biosynthetically from L-tyrosine via the hydroxylation of p-hydroxyphenylacetonitrile, III. (3R)- and (3S)-L-[3-3H1]tyrosine, prepared by enzymic hydroxylation of the corresponding phenylalanines, were fed separately to shoots fr...
متن کاملIsolation and reconstitution of cytochrome P450ox and in vitro reconstitution of the entire biosynthetic pathway of the cyanogenic glucoside dhurrin from sorghum.
A cytochrome P450, designated P450ox, that catalyzes the conversion of (Z)-p-hydroxyphenylacetaldoxime (oxime) to p-hydroxymandelonitrile in the biosynthesis of the cyanogenic glucoside beta-D-glucopyranosyloxy-(S)-p-hydroxymandelonitrile (dhurrin), has been isolated from microsomes prepared from etiolated seedlings of sorghum (Sorghum bicolor L. Moench). P450ox was solubilized using nonionic d...
متن کاملInvolvement of Cytochrome P-450 in the Biosynthesis of Dhurrin in Sorghum bicolor (L.) Moench.
The biosynthesis of the tyrosine-derived cyanogenic glucoside dhurrin involves N-hydroxytyrosine, (E)- and (Z)-p-hydroxyphenylacetaldehyde oxime, p-hydroxyphenylacetonitrile, and p-hydroxymandelonitrile as intermediates and has been studied in vitro using a microsomal enzyme system obtained from etiolated sorghum (Sorghum bicolor [L.] Moench) seedlings. The biosynthesis is inhibited by carbon m...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- The Journal of biological chemistry
دوره 250 12 شماره
صفحات -
تاریخ انتشار 1975