The ability of a specialized herbivore to overcome the chemical defense of a particular plant taxon not only makes it accessible as a food source but may also provide metabolites to be exploited for communication or chemical defense. Phyllotreta flea beetles are adapted to crucifer plants (Brassicales) that are defended by the glucosinolate-myrosinase system, the so-called "mustard-oil bomb." T...

Plant myrosinases and glucosinolates constitute a defence system in cruciferous plants towards pests and diseases. We have purified for the first time a non-plant myrosinase from the cabbage aphid Brevicoryne brassicae (L.) to homogeneity. The protein was N-terminally blocked and protease (trypsin and lys c) degradation gave peptides of which five were sequenced. The protein is a dimer with sub...

The breakdown of glucosinolates, a group of thioglucoside compounds found in cruciferous plants, is catalysed by dietary or microbial myrosinase. This hydrolysis releases a range of breakdown products among which are the isothiocyanates, which have been implicated in the cancer-protective effects of cruciferous vegetables. The respective involvement of plant myrosinase and gut bacterial myrosin...

In mature seeds of Brassica napus three major and three minor myrosinase isoenzymes were identified earlier. These myrosinases are known to be encoded by at least two different families of myrosinase genes, denoted MA and MB. In the work described in this paper the presence of different myrosinase isoenzymes in embryos, seedlings, and vegetative mature tissues of B. napus was studied and relate...

The protective effects of brassica vegetables against cancer may be partly related to their glucosinolate content. Glucosinolates are hydrolysed by plant myrosinase following damage of plant tissue. Isothiocyanates are one of the main groups of metabolites of glucosinolates and are implicated in the preventive effect against cancer. During cooking of brassica the glucosinolate-myrosinase system...

Fully developed horseradish (Armoracia rusticana Gaertn., Mey., & Scherb.) roots from 27 accessions and leaves from a subset of 9 accessions were evaluated for glucosinolates and myrosinase enzyme activity. Eight different glucosinolates were detected (based on HPLC retention times as desulfoglucosinolates) in both root and leaf tissues. The sum of these glucosinolates, referred to as total, ra...

Myrosinase, which is present in cruciferous plant species, plays an important role in the hydrolysis of glycosides such as glucosinolates and is involved in plant defense. Brassicaceae myrosinases are diverse although they share common ancestry, and structural knowledge about myrosinases from cabbage (Brassica oleracea) was needed. To address this, we constructed a three-dimensional model struc...

The purified and thermo stable myrosinase from cauliflower seedlings was immobilized by 3.5% agar agar matrix and immobilized myrosinase chips were stored in extraction buffer. After 48 hours 30% enzyme activity was exuded into extraction media from immobilized enzyme chips. Effect of some metal ions and organic solvents on the activity of immobilized cauliflower myrosinase was studied. Amongst...

On the basis of previous studies on the mechanism-based inhibition, activation, and active site structure of myrosinase(s) isolated from Sinapis alba and other cruciferous seeds, crambe myrosinase shows uncommon properties and behavior. For this reason homogeneous crambe myrosinase was isolated and investigated to establish the most important physicochemical features, including kinetic properti...

Myrosinases have significant scientific and medical implications. Unfortunately, detection purification of myrosinase from microbes requires the use highly cost substrates (glucosinolates) such as sinigrin expensive instruments Fast Protein Liquid Chromatography or ion exchange chromatography. In this work, we used only 20 mL bacterial culture supplemented with (10 mM) to obtain partially purif...