Methodology for fast evaluation of Bacillus thuringiensis crystal protein content

Nenhuma Miniatura disponível



Título da Revista

ISSN da Revista

Título de Volume


Soc Brasileira Microbiologia


The development of the production and use of Bacillus thuringiensis Brazil at a commercial scale faces certain difficulties, among them the establishment of efficient methodologies for the quantitation of toxic products to be commercialized. Presently, the amount of toxin is given in percentage by analyzing the samples total protein content. Such methodology however, does not measure the actual amount of active protein present in the product, since most strains express different endotoxin genes and might even produce b-toxin. Since the various types of toxins exhibit different antigenic characteristics, this work has as objective the utilization of fast immunological techniques to quantify the level of crystal protein. Crystal protein produced by a subspecies of Bacillus thuringiensis var, israelensis was purified by ultracentrifugation and utilized to immunize rabbits and to produce hiperimmune sera. Such sera were latter used to evaluate the level of proteins on commercial bioinsecticide and on laboratory cultures of B. thuringiensis through the immunodot technique. The results were obtained by comparison of data obtained from reactions with known concentrations of crystal protein permitting to evaluate the level of such protein on various materials.



Bacillus thuringiensis, crystal protein, immunological methods

Como citar

Brazilian Journal Of Microbiology. Sao Paulo: Soc Brasileira Microbiologia, v. 31, n. 3, p. 216-219, 2000.