Profiles of the body-surface proteolytic system of honey bee queens, workers and drones: Ontogenetic and seasonal changes in proteases and their natural inhibitorsKrzysztof Grzywnowicz, Aneta Ciołek, Agnieszka Tabor and Magdalena Jaszek
Department of Biochemistry, Maria Curie-Skşodowska University, Plac M.C. Skşodowskiej 3, 20-031 Lublin, Poland
Received 23 August 2007 – Revised 24 July 2008 – Accepted 29 July 2008 - Published online 13 December 2008
Abstract - We describe how protease and protease inhibitor activity patterns vary during ontogenesis, with season, and in relation to caste and sex in the honey bee (Apis mellifera). Extraction of body surfaces with water and detergent was followed by the in vitro analysis of proteolytic activity and protease inhibitor level, as well as the electrophoretic separation of extracts in polyacrylamide gels. In in vitro experiments, we compared two groups of detectable proteolytic activities: neutral and alkaline water-soluble versus acidic detergent-soluble. The most active proteases appeared to be acidic ones and were detected on drone pupae in spring. The most distinct and most active protease bands in electrophoretic separations were those obtained for neutral and alkaline activities on queens in all seasons. The highest levels of protease inhibitor activities in vitro were obtained from worker samples in all seasons. The enzymatic properties suggest that all catalytic types of proteases were present in the extracts, but at different activity levels, depending on pH: asparagine and cysteine proteases at pH 2.5, cysteine proteases and metalloproteases at pH 7.0, and serine proteases at pH 11.5, respectively.
Key words: honey bee / proteases / protease inhibitors / body surface proteolysis / zymography
© INRA, DIB-AGIB, EDP Sciences 2008