Effects of the P20 protein from Bacillus thuringiensis israelensis on insecticidal crystal protein Cry4Ba.

The accessory protein P20 from Bacillus thuringiensis israelensis has been defined as an important molecular chaperone for forming crystal Cyt1Aa, and enhancing Cry11Aa and Cry4Aa expression. To investigate its putative role in Cry4Ba delta-endotoxin production and toxicity, a p20 gene was cloned and introduced into B. thuringiensis recombinant strain expressing cry4Ba type gene (cry4BLB).

Isolation of the Bacillus thuringiensis plasmid carrying Bacthuricin F4 coding genes and evidence of its conjugative transfer.

Introduction: Conjugation is an excellent natural mode of DNA transfer in vivo between bacteria, particularly when these conjugative elements carry technological traits such as bacteriocin encoding genes. In the present work, the bacteriocinogenic plasmid pIBF4 from Bacillus thuringiensis responsible of Bacthuricin F4 synthesis was isolated and characterized.

Methodology: To isolate pIBF4, the total plasmid DNA from a non-bacteriocin transposant carrying the mini-Tn10 spectinomycin selective marker was extracted and used to transform Escherichia coli strain Top10.

Purification and characterization of a new Bacillus thuringiensis bacteriocin active against Listeria monocytogenes, Bacillus cereus and Agrobacterium tumefaciens.

This study reports on the identification, characterization and purification of a new bacteriocin, named Bacthuricin F103, from a Bacillus thuringiensis strain BUPM103. Bacthuricin F103 production began in the early exponential phase and reached a maximum in the middle of the same phase. Two chromatographic methods based on high performance liquid chromatography and fast protein liquid chromatography systems were used to purify Bacthuricin F103.

Generation of Mini-Tn10 transposon insertion mutant library of Bacillus thuringiensis for the investigation of genes required for its bacteriocin production.

Bacillus thuringiensis strain BUPM4 is known for its ability to produce a bacteriocin, called Bacthuricin F4 (BF4), which inhibits the growth of several Gram-positive bacteria and particularly Bacillaceae. This study aimed to use the insertional transposon mutagenesis approach for disrupting and thus identifying genes associated with BF4 synthesis. Here, the mini-Tn10 transposon was used to generate a library of B.