title: In vivo Responses of Honey Bee Midgut Proteases to Two Protease Inhibitors from Potato.
abstract: Potato protease inhibitors, POT-1 and POT-2, were fed to newly emerged adult honey bees in cages at different doses in either sugar syrup (0.2 or 0.01% w:v) or pollen food (1 or 0.2% w:w). In vivo activities of three digestive endopeptidases (trypsin, chymotrypsin and elastase) and one exopeptidase (leucine aminopeptidase; LAP) were measured after 3 or 8days' exposure of bees to inhibitor. Enzyme activities were significantly lower at day 8 than at day 3, except for elastase, which did not change. POT-2 significantly reduced the activity of all endopeptidases at both timepoints, regardless of the dose level or the medium in which the inhibitor was administered. POT-1 acted in a similar manner, except that 0.01% POT-1 in syrup had no effect on bees. There was no consistent trend in changes in LAP activity. Bees fed either inhibitor at 1% in pollen or at 0.2% in syrup had significantly reduced lifespans, with the effect of the pollen treatment being greater than the syrup treatment. The survival of bees fed POT-1 or POT-2 at 0.2% in pollen or 0.01% in syrup did not differ from the controls.
authors.affiliation: Horticulture and Food Research Institute of New Zealand Limited, Private Bag 11030, Palmerston North, New Zealand
authors.forename: H S.
authors.initials: HS
authors.lastname: Gatehouse
authors.forename: J T.
authors.initials: JT
authors.lastname: Christeller
authors.forename: E P.J.
authors.initials: EP
authors.lastname: Burgess
authors.forename: L A.
authors.initials: LA
authors.lastname: Malone