Bacillus thuringiensis pesticides

As is the case with identifications based on protein molecular masses, it appears that the use of tryptic or other peptide masses as the basis for identification is extended with difficulty to mixtures of microorganisms. This reflects unpredictable suppression. Another limitation is redundancy of peptide masses across several microorganisms. For example, the most abundant proteins (SASPs), and thus the most abundant peptides, in spores of Bacillus anthracis and the closely related pesticide Bacillus thuringiensis have extensive sequence homology.25,82... 

For understandable reasons, Trouvelot lost his interest in entomology, but became a clever astronomist. Materials used to fight back gypsy moth include the chemical pesticide Dimilin , an inhibitor of chitin synthesis. The biological pesticides, Bacillus thuringiensis, or naturally occurring gypsy moth virus is also quite useful. 

Biological Pesticides, Bacillus thuringiensis, Integrated Pest Management, Myrothecium, Formulations, Bacillus subtilis, Biopesticides, Larvicides, Biological Control... 

A possible example of this thesis is the crystalline insect toxin found in Bacillus thuringiensis spores and discussed here by Dr. Anderson. Although neither the bacillus nor its spores exhibit useful antibiotic activity against other microorganisms, the very specific toxicity to insects has become of major commercial interest. The enormous number and variety of fungal species available for further examination must lead inevitably to one or more which produces pesticidal metabolites. 

Reductionist approaches to problems in agriculture are seen as symptomatic treatments. There is evidence of the resistance of insects to the pesticides used in combination with GMOs, or to Bacillus thuringiensis that is used in insect-resistant GMOs (Stix 1998, McDonald and Linde 2002). 

The National Research Council Committee states that attempts to assess food safety based solely on the process are scientifically unjustified. Rather than adding a general label about the process with which a plant variety was developed, it would make more sense to label food so that consumers are informed about what is actually in or on the food. But this, too, is not necessarily helpful. For some people it may be informative to read a label that says, may contain traces of carbamate pesticides, which at high concentrations are known to cause death of animals or may contain trace amounts of purified Bacillus thuringiensis protein, which kill Leptidoptera (a class of insects). But is it helpful to most consumers who are not familiar with the science ... 

Bernstein, L., J. A. Bernstein, M. Miller, S. Tierzieva, D. I. Bernstein, Z. Lummus, M. K. Selgrade, D. L. Doerfler, and V. L. Seligy. 1999. Immune responses in farm workers after exposure to Bacillus thuringiensis pesticides. Environmental Heath Perspectives 107 575-582. 

McClintock JT, Schaffer CR, and Sjoblad RD (1995) A comparative review of the mammalian toxicity of Bacillus thuringiensis-bAsed pesticides. Pesticide Science 45 95-105. 

US Environmental Protection Agency (1998) Reregistration Eligibility Decision (RED) Bacillus thuringiensis. Washington, DC Office of Prevention, Pesticides and Toxic Substances. 

Strains isolated from commercial products (supposed to containing Bacillus thuringiensis and used as organic pesticides by farmers) in the Laboratory of Bacteriology (Toulouse, France), and identified on the basis of parasporal crystal ceU inlusions presenceisolates from commercial preparations of biopesticides... 

Manzano M, Giusto C, lacumin L, Cantoni C, Comi G (2008) Molecular methods for Bacillus cereus and Bacillus thuringiensis from humans, pesticides and foods, differentiation. Acta Alim 10 1-9... 

Schnepf E, Crickmore N, Van Rie J, Lereclus D, Baum J, Feitelson J, Zeigler DR, Dean DH (1998) Bacillus thuringiensis and its pesticidal crystal proteins. Microbiol Mol Biol Rev 62 774-806... 

The remainder of this presentation will focus on the applications of some of these technologies toward the development of improved versions of one type of biological pesticide, the bacterial insect pathogen Bacillus thuringiensis. 

Applications of immunoassay to pesticide chemistry have been described which address some difficult problems in analysis by classical methods. These include stereospecific analysis of optically active compounds such as pyrethroids (38), analysis of protein toxins from Bacillus thuringiensis (5,37), and compounds difficult to analyze by existing methods, such as diflubenzuron (35) and maleic hydrazide (15 also Harrison, R.O. Brimfield, A.A. Hunter, K.W.,Jr. Nelson, J.O. J. Agric. Food Chem. submitted). An example of the excellent specificity possible is seen in assays for parathion (10) and its active form paraoxon (3). Some immunoassays can be used directly for analysis without extensive sample extraction or cleanup, dramatically reducing the work needed in typical residue analysis. An example of this is given in Figures 2 and 3, comparing the direct ELISA analysis of molinate in rice paddy water to the extraction required before GC analysis. 

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