Glucosinolates are thioglucosides found in brassica vegetables that when hydrolyzed at the S-glucose bond create a suite of products involved in plant defense, flavor, and human health. Glucosinolates react with myrosinase [thioglucoside
Glucosinolates are thioglucosides found in Brassica vegetables that when hydrolyzed at the S-glucose bond create a suite of products involved in plant defense, flavor, and human health. Consumption of vegetables containing glucosinolates has been
A full-length cDNA (ArMY1) encoding myrosinase (β-thioglucoside glucohydrolase, EC 3.2.3.1) was cloned from horseradish (Armoracia rusticana) root. ArMY1 has an open reading frame of 1614 nucleotides with a deduced protein of 538 amino acids and molecular mass of 61.6 kD. ArMY1 shows highest overall amino acid identity (72%) with Arabidopsis thaliana myrosinase TGG2. ArMY1 mRNA signal of about 1.95 kb was detected in the leaves and roots of horseradish, but not in the leaves of broccoli. Heterologous expression of ArMY1 in baculovirus-infected Sf9 cells resulted in an immunologically active recombinant ArMY1 protein when probed with myrosinase-specific monoclonal antibody 3D7 with apparent mass 65 kD. Phylogenetic analysis showed that ArMY1 does not cluster with any of the current myrosinase subfamilies, i.e., the MA, MB, and MC subfamilies, and may represent a novel myrosinase subfamily in root tissue. This is the first report of cloning of myrosinase cDNA from horseradish root. It provides important sequence information that will enable further studies of myrosinase expression patterns and their interaction with myrosinase–binding proteins and other myrosinase-associated proteins.
., 2009 )]. Glucosinolates, consisting of β-thioglucoside N -hydroxysulfate, a side chain, and a β- d -glucopyranose moiety, are divided into three groups based on their amino acid precursors: aliphatic GSs (methionine, leucine, iso-leucine), indole GSs