Nonenzymatic Glycosylation of Lepidopteran-Active Bacillus thuringiensis Protein Crystals

Authors

Meenakshi Bhattacharyi, University of Nebraska-Lincoln
Bradley A. Plantz, University of Nebraska-LincolnFollow
Jane D. Swanson-Kobler, University of Nebraska-Lincoln
Kenneth W. Nickerson, University of Nebraska-LincolnFollow

Date of this Version

August 1993

Comments

Published in APPLIED AND ENVIRONMENTAL MICROBIOLOGY, Aug. 1993, p. 2666-2672 Vol. 59, No. 8. Copyright X 1993, American Society for Microbiology. Used by permission.

Abstract

We used high-pH anion-exchange chromatography with pulsed amperometric detection to quantify the monosaccharides covalently attached to Bacillus thuringiensis HD-1 (Dipel) crystals. The crystals contained 0.54% sugars, including, in decreasing order of prevalence, glucose, fucose, arabinose/rhamnose, galactose, galactosamine, glucosamine, xylose, and mannose. Three lines of evidence indicated that these sugars arose from nonenzymatic glycosylation: (i) the sugars could not be removed by N- or O-glycanases; (ii) the sugars attached were influenced both by the medium in which the bacteria had been grown and by the time at which the crystals were harvested; and (iii) the chemical identity and stoichiometry of the sugars detected did not fit any known glycoprotein models. Thus, the sugars detected were the product of fermentation conditions rather than bacterial genetics. The implications of these findings are discussed in terms of crystal chemistry, fermentation technology, and the efficacy of B. thuringiensis as a microbial insecticide.