Analytical Chemistry of Bacillus thuringiensis

Abstract

This article presents a review of the analytical chemistry of Bacillus thuringiensis and an introduction to the remaining chapters in this book. Included are critical evaluations of the appropriate analytical targets, sample preparation and determination by bioassay, immunoassay, electrophoresis and chromatography. Issues of purifying reference standards are also discussed.The bacterial species Bacillus thuringiensis (BT) consists of a variety of strains which are toxic to insects. Interest in products derived from these strains has undergone a renaissance in recent years due to environmental concerns associated with the use of synthetic pesticides. This has given rise to active BT research and development programs in industry, academia and government worldwide (1,2). Although there are recent reviews available on the molecular biology (3,4) and mode of action (5) of these materials, the information available on actually quantifying the active components is scattered throughout the literature. This review covers those aspects of BT technology relevant to quantifying the active product constituents in novel strains, genetically engineered plants and microbes, and in the environment. AnalytesRational analysis requires a thorough knowledge of the object of the analysisthe analyte or analytes. Definition of the active constituents of BT is complex because the fermentation broths which form the basis of experimental and production materials are mixtures of soluble and insoluble proteins, spores, bacterial metabolites, and growth media components. These multiple "analytes" interact synergistically to different degrees as toxins to different target insects.The main toxins of BT are a series of structurally related proteins which are present in the sporulated cultures as crystalline inclusion bodies. These

Venom Proteins of the Parasitoid Wasp Nasonia vitripennis: Recent Discovery of an Untapped Pharmacopee

“…The latter aspect is incredibly important as there are relatively few naturally occurring toxins with dipteran specificity available for use in the construction of selective bioinsecticides. The most widely used are produced by bacteria such as Bacllius thuringiensis and B. sphaericus , but are limited because the toxins are only active against aquatic stages of dipteran pests [ 96 , 97 ]. Thus, the specificity of venom, and presumably individual venom proteins, from N. vitripennis offers promise of adding powerful new chemical weapons to the arsenal of compounds used to control medically and agriculturally important fly pests.…”

Analysis of insecticidal proteins from Bacillus thuringiensis and recombinant Escherichia coli by capillary electrokinetic chromatography

“…3B (curve a), the addition of phytic acid at low concentration (20 mM) improved the baseline separation of the toxins significantly (R s = 1.4 and 1.7) and increased the separation time (26-30 min) due to an increase in the current to 106 mA. Phytic acid in water has a very high pH (11)(12) and contributed substantially to the current due to its ionic strength. For ionic strength management, the borate concentration had to be decreased with an increase in the phytic acid concentration.…”

“…To our knowledge, CE has not been developed as an analytical technique to resolve Bt toxins [12]. The low sample volume capability, high separation efficiency, simplicity, speed of analysis, and ease of operation make CE a powerful method for analytical and quality control applications.…”

Bacillus thuringiensis growth and toxicity

“…general aspects of BT; Ltithy et al (15), with a complete analysis of BT metabolism; Aronson et al (16), dealing with BT and other insect pathogens; Rowe and Margaritis (17), covering almost all subjects related to biotechnology of BT (including economic aspects); Whiteley and Schnepf (9) and H6fte and Whiteley (18), two excellent reviews on the molecular biology of BT crystal toxin; Priest (19), a short review on mosquito control; and Gill et al (20), a thorough analysis of BT toxin mode of action. At least three books have been published, dealing with different aspects of BT (21)(22)(23).…”