Characterization, N-terminal sequencing and classification of Tolworthcin 524: A bacteriocin produced by Bacillus thuringiensis subsp. tolworthi

Publication date: December 2014 Source:Microbiological Research, Volume 169, Issue 12 Author(s): Rubén D. Pacheco-Cano , Norma M. de la Fuente-Salcido , Rubén Salcedo-Hernández , M. Fabiola León-Galván , Dennis K. Bideshi , Gustavo Hernández-Guzmán , J. Eleazar Barboza-Corona Bacteriocins synthesized by entomopathogenic Bacillus thuringiensis are gaining attention owing to their inhibitory effects against a wide variety of pathogenic bacteria. In the present study, we purified and characterized Tolworthcin 524, a bacteriocin synthesized by B. thuringiensis subsp. tolworthi, and compared it with other bacteriocins synthesized by B. thuringiensis. Tolworthcin 524 was separated and purified from the secretome of B. thuringiensis by fast protein liquid chromatography with a gel filtration column to obtain yields of 17% and a specific activity of ∼3600U/mgprotein. The purified product showed two peptides of ∼9 and 6kDa with antimicrobial activity in a gel-screening assay. The purified product was analyzed by two-dimensional electrophoresis and the resolved peptides of ∼9 and 6kDa with isoelectric points of ∼8 were sequenced. Partial sequences (METPVVQPR and DWTCWSCLVCAACS) were obtained suggesting that the ∼9 and 6kDa correspond to the prebacteriocin and mature Tolworthcin 524, respectively. Sequences showed high identity with Thurincin H and Thuricin 17 and had a conserved motif with other bacteriocins of B. thuringiensis. Based on sequence data, Tolwo...
Source: Microbiological Research - Category: Infectious Diseases Source Type: research