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Aminopeptidase N as a Receptor for Bacillus Thuringiensis Cry Toxins

  • Ryoichi Sato
Chapter

Abstract

Bacillus thuringiensis, a Gram-positive bacterium, produces various insecticidal proteinaceous crystal inclusions during sporulation (Holte and Whiteley, 1989). These inclusions consist of one or more protein protoxins that are grouped into 30 classifications (Cry 1–32 and Cyt 1–2) according to their amino acid sequences (Crickmore et al., 1998, 2001). When susceptible insects ingest this bacterium, the crystal inclusions are solubilized in the alkaline environment of the insect midgut and processed proteolytically to yield smaller active Cry toxins (Gill et al., 1992). The Cry toxins bind specifically to receptor molecules in the midgut epithelial cells ofhost insects (Hofmann et al., 1988a; Hofmann et al., 1988b; Van Rie et al., 1989, 1990), altering the ion permeability of the midgut cell membranes (Harvey and Wolfersberger,1979). A net influx of ions and an accompanying influx of water cause the cells to swell and lyse (Luthy and Ebersold, 1981; Knowles and Ellar, 1987). The formation of either cation-selective (Knowles et al., 1989; Lorence et al., 1995; Slatin et al., 1990) or small nonspecific pores in the membrane has been proposed as a possible mechanism for the toxin action (Carroll et al., 1993).

Keywords

Bacillus Thuringiensis Brush Border Membrane Gypsy Moth Brush Border Membrane Vesicle Planar Lipid Bilayer 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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© Springer Science+Business Media New York 2002

Authors and Affiliations

  • Ryoichi Sato
    • 1
  1. 1.Laboratory of Molecular Mechanism of Bio-Interaction, Graduate School of Bio-Applications & Systems EngineeringTokyo University of Agriculture and TechnologyNakamachi, Koganei, TokyoJapan

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