Purification and characterization of β-glucosidase from honey bees ( Apis mellifera)

• Published in: Insect biochemistry and molecular biology Vol. 32; no. 6; pp. 679 - 690
• Main Authors: Pontoh, J, Low, N.H
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-06-2002
• Subjects: Animals; Bees - enzymology; beta-Glucosidase - analysis; beta-Glucosidase - isolation & purification; Characterization; Electrophoresis, Polyacrylamide Gel; Honey bee; Honey sac; Hydrogen-Ion Concentration; Hypopharyngeal glands; MALDI-TOF-MS; Peptide Mapping; Purification; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization - methods; Temperature; Ventriculus; β-Glucosidase; Characterization; Honey sac; β-Glucosidase; MALDI-TOF-MS; Purification; Ventriculus; Hypopharyngeal glands; Honey bee
• ISSN: 0965-1748; 1879-0240
• DOI: 10.1016/S0965-1748(01)00147-3

β-glucosidase has been purified from the ventriculus and honey sac of
Apis mellifera using a combination of anion- and cation-exchange, hydroxyapatite and gel-permeation chromatography. In addition, β-glucosidase from the hypopharyngeal glands has been partially purified using anion-exchange and gel-permeation chromatography. The purified β-glucosidase gave a positive result by glycoprotein staining. This β-glucosidase consists of only one subunit and has
M
r of 72 kDa as determined by SDS–PAGE. IEF–PAGE showed several bands with pIs ranging from 4.5 to 4.8. These multiform proteins have been proposed as having different degrees of glycosylation. The pH optimum of the purified β-glucosidase from the ventriculus and honey sac are 5.0. These enzymes were stable at temperatures up to 50 °C and have a relatively wide pH stability range of 4.0 to 9.0. MALDI-TOF-MS peptide mass maps of purified β-glucosidase from the ventriculus, honey sac and hypopharyngeal glands showed six matching masses. These results indicate that the β-glucosidase isolated from the hypopharyngeal glands, honey sac and ventriculus is the same. It is proposed that β-glucosidase is produced in the hypopharyngeal glands, secreted into the mouth during feeding and then passes to the honey sac. From the honey sac, this enzyme is transferred into honeycomb cells and the ventriculus.