Bacillus thuringiensis: a successful insecticide with new environmental features and tidings

Abstract

Bacillus thuringiensis (Bt) is known as the most successful microbial insecticide against different orders of insect pests in agriculture and medicine. Moreover, Bt toxin genes also have been efficiently used to enhance resistance to insect pests in genetically modified crops. In light of the scientific advantages of new molecular biology technologies, recently, some other new potentials of Bt have been explored. These new environmental features include the toxicity against nematodes, mites, and ticks, antagonistic effects against plant and animal pathogenic bacteria and fungi, plant growth-promoting activities (PGPR), bioremediation of different heavy metals and other pollutants, biosynthesis of metal nanoparticles, production of polyhydroxyalkanoate biopolymer, and anticancer activities (due to parasporins). This review comprehensively describes recent advances in the Bt whole-genome studies, the last updated known Bt toxins and their functions, and application of cry genes in plant genetic engineering. Moreover, the review thoroughly describes the new features of Bt which make it a suitable cell factory that might be used for production of different novel valuable bioproducts.

Biocontrol of Citrus Canker Disease Caused by Xanthomonas citri subsp. citri Using an Endophytic Bacillus thuringiensis

“…B. thuringiensis is a Gram-positive, soil-borne bacterium. It has been widely used as a biocontrol agent and bioinsecticide (Chattopadhyay et al, 2004; Jouzani et al, 2017). …”

Selection of Bacillus thuringiensis strains in citrus and their pathogenicity to Diaphorina citri (Hemiptera: Liviidae) nymphs

“…Among the entomopathogens, Bacillus thuringiensis Berliner (Bacillales: Bacillaceae) (Bt) has been widely used in biopesticide formulations containing bacterial spores and crystals (Schnepf et al ., ; Jouzani et al ., ). Bt has high activity against immature stages of several pest insects belonging to different orders, such as Lepidoptera, Coleoptera, Diptera (Xu et al ., ), Hemiptera (Porcar et al ., ; Torres‐Quintero et al ., ), Hymenoptera, and Orthoptera (Bravo et al ., ).…”

Structural insights into the insecticidal Vip3A toxin ofBacillus thuringiensis

“…These features makes them good candidates for combined application with Cry toxins in transgenic crops to broaden the insecticidal spectrum and to prevent or delay resistance 1, 9, 14 . The structural features and insecticidal mechanisms of Cry toxins have been studied in detail, which has been crucial to their widespread application 2–6, 19 . However, despite of the fact that Vip3 toxins were identified almost 25 years ago 29 , their mode of action remains poorly understood.…”

“…The entomopathogenic bacteria Bacillus thuringiensis (Bt), is the most widely used microbial insecticide in the world 1, 2 . It is renowned for its ability to produce insecticidal crystal proteins (Cry toxins) during its sporulation phase, which have been widely used in the prevention and control of agricultural pests through the development of transgenic plants or Bt-based biopesticides 3–5 .…”