Enzyme-linked immunosorbent assay detection and bioactivity of Cry1Ab protein fragments

Environ Toxicol Chem. 2016 Dec;35(12):3101-3112. doi: 10.1002/etc.3497. Epub 2016 Jul 19.

Abstract

The continuing use of transgenic crops has led to an increased interest in the fate of insecticidal crystalline (Cry) proteins in the environment. Enzyme-linked immunosorbent assays (ELISAs) have emerged as the preferred detection method for Cry proteins in environmental matrices. Concerns exist that ELISAs are capable of detecting fragments of Cry proteins, which may lead to an overestimation of the concentration of these proteins in the environment. Five model systems were used to generate fragments of the Cry1Ab protein, which were then analyzed by ELISAs and bioassays. Fragments from 4 of the model systems were not detectable by ELISA and did not retain bioactivity. Fragments from the proteinase K model system were detectable by ELISA and retained bioactivity. In most cases, ELISAs appear to provide an accurate estimation of the amount of Cry proteins in the environment, as detectable fragments retained bioactivity and nondetectable fragments did not retain bioactivity. Environ Toxicol Chem 2016;35:3101-3112. © 2016 SETAC.

Keywords: Bioassay; Cross-validation; Cry protein; Environmental fate; Enzyme-linked immunosorbent assay.

MeSH terms

  • Animals
  • Bacillus thuringiensis / metabolism
  • Bacillus thuringiensis Toxins
  • Bacterial Proteins / analysis*
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Bacterial Proteins / pharmacology
  • Biological Assay
  • Electrophoresis, Polyacrylamide Gel
  • Endotoxins / analysis*
  • Endotoxins / genetics
  • Endotoxins / metabolism
  • Endotoxins / pharmacology
  • Enzyme-Linked Immunosorbent Assay*
  • Hemolysin Proteins / analysis*
  • Hemolysin Proteins / genetics
  • Hemolysin Proteins / metabolism
  • Hemolysin Proteins / pharmacology
  • Lethal Dose 50
  • Moths / drug effects
  • Moths / metabolism
  • Plants, Genetically Modified / metabolism

Substances

  • Bacillus thuringiensis Toxins
  • Bacterial Proteins
  • Endotoxins
  • Hemolysin Proteins
  • insecticidal crystal protein, Bacillus Thuringiensis