Bacillus thuringiensis: a century of research, development and commercial applications

Abstract

SummaryBacillus thuringiensis (Bt) is a soil bacterium that forms spores during the stationary phase of its growth cycle. The spores contain crystals, predominantly comprising one or more Cry and ⁄ or Cyt proteins (also known as d-endotoxins) that have potent and specific insecticidal activity. Different strains of Bt produce different types of toxin, each of which affects a narrow taxonomic group of insects. Therefore, Bt toxins have been used as topical pesticides to protect crops, and more recently the proteins have been expressed in transgenic plants to confer inherent pest resistance. Bt transgenic crops have been overwhelmingly successful and beneficial, leading to higher yields and reducing the use of chemical pesticides and fossil fuels. However, their deployment has attracted some criticism particularly with regard to the potential evolution of pest-resistant insect strains. Here, we review recent progress in the development of Bt technology and the countermeasures that have been introduced to prevent the evolution of resistant insect populations.

Genetic and Biochemical Characterization of a Gene Operon for trans-Aconitic Acid, a Novel Nematicide from Bacillus thuringiensis

“…Recent, research has classified B. thuringiensis as a bacterial pathogen of alternative nematode hosts (2)(3)(4), which may help to explain the complex ecology of B. thuringiensis that was previously thought to have a sole insect host (2,5,6). This finding further contextualizes already established interactions between B. thuringiensis and nematodes (1)(2)(3)(4)7), including free-living and parasitic species.…”

The Metabolic Regulation of Sporulation and Parasporal Crystal Formation in Bacillus thuringiensis Revealed by Transcriptomics and Proteomics

“…To date, B. thuringiensis has been reported to produce over 760 kinds of ICPs that are classified into 72 Cry groups (723 kinds) and 3 Cyt groups (37 kinds) (http://www.lifesci.sussex.ac.uk/Home/ Neil Crickmore/Bt/; November, 2012), which endow it with an extensive spectrum of insecticidal activity (4). Moreover, many studies have confirmed that B. thuringiensis is one of the safest microbial products known (5). Therefore, it is widely used as a biopesticide for agricultural and public health applications.…”

The role of biotechnology in agricultural production and food supply

“…GM soybean has made rapid strides in recent decades, and its cultivation area has been increasing yearly. Currently, genetic modification has been successful in maize, tomato, rice and cotton plantations (Sanahuja et al, 2011;Tabashnik et al, 2011), mainly by inserting exogenous genes (transgene) that encode a protein that is toxic to specific pests.…”