The interplay between toxin-releasing β-glucosidase and plant iridoid glycosides impairs larval development in a generalist caterpillar, Grammia incorrupta (Arctiidae)

Pseudautomeris brasiliensis(Lepidoptera: Saturniidae) andStenomasp. (Lepidoptera: Elachistidae) Feeding on Crops ofCtenanthe kummeriana(Marantaceae) in Brazil and an Associate Parasitoid,Enicospilus tenuigena(Hymenoptera: Ichneumonidae)

“…The feeding damage caused by the larvae of D. sacrifica on E. erythropappus confirms its general feeding habit as a defoliator (Bai et al 2010;Pankoke et al 2012;Zaché et al 2012). This insect is characterized by a white cross-like mark on the forewing.…”

Deciphering the route to cyclic monoterpenes in Chrysomelina leaf beetles: source of new biocatalysts for industrial application?

“…Enzymes that catalyze such reactions often belong to the glycosyl hydrolase family 1 (GH1) according to CAZy [96,97]. Whereas in plants, GH1s play an important role in the activation of glucosides for defense purpose [98][99][100][101], insects use those enzymes mainly for digestion, either in the gut or in the salivary glands [24,102,103]. In addition to this, GH1s may also be involved in the production of chemical defenses widely distributed in insects [104].…”

“…To date, it has been shown that iridoid toxicity can be attributed to the highly reactive aglycones that are released from the corresponding nontoxic iridoid glucosides that are often safely stored in plant organelles [18,19]. Glycoside hydrolysis can be achieved nonenzymatically or enzymatically by β-glucosidases (hydrolases, EC 3.2.1.21) produced by the plants themselves [20][21][22] or by their enemies [12,13,23,24]. If the resulting compound is a reactive aldehyde, it has the ability to link irreversibly and nonselectively essential cellular components including proteins.…”

“…This may affect the physiological processes of invasive organisms directly and/or decrease the nutritive value of dietary proteins considerably [25][26][27][28]. Although a universal target of iridoids has not been defined, these rather nonspecific effects contribute to an increased mortality of, for example, nonadapted herbivores feeding on iridoid glycoside-containing diets [24].…”

Impact of the dual defence system of Plantago lanceolata (Plantaginaceae) on performance, nutrient utilisation and feeding choice behaviour of Amata mogadorensis larvae (Lepidoptera, Erebidae)

“…After centrifugation at +4 °C and 5900 g for 10 minutes, the β-glucosidase activity in the supernatants was determined with 30 mM of aucubin dissolved in 0.1 M citrate-phosphate buffer, pH 5.0 at 30 °C under conditions such that the β-glucosidase activity was proportional to protein concentration and time. The enzymatic reaction was stopped by heat-denaturation and the amount of glucose released from aucubin was determined using a coupling enzyme reaction (Pankoke et al 2012;. The amount of soluble protein of each sample was determined using the Bradford assay and bovine serum albumin as standard (Bradford, 1976).…”