Dariush Gholami1,2, Tannaz Goodarzi1, Saeed Aminzadeh1, Seyed Mehdi Alavi1, Nasrin Kazemipour3, Naser Farrokhi4. 1. Department of Bioprocess Engineering, National Institute for Genetic Engineering and Biotechnology, Tehran, Iran. 2. Science Department, Sistan-Baluchistan University, Zahedan, Iran. 3. School of Veterinary Medicine, Shiraz University, Shiraz, Iran. 4. Department of Biotechnology, Faculty of New Technologies and Energy Engineering, Shahid Beheshti University, Tehran, Iran.
Abstract
BACKGROUND: Xanthomonas citri subsp. citri (Xcc), the causative agent of bacterial citrus canker, has affected citriculture worldwide. Varieties of means have been used to minimize its devastating effects, but no attention has been given to bacteriocins. OBJECTIVES: Here and for the first time, we report the isolation and characterization of two novel bacteriocins. MATERIALS AND METHODS: Secretome containing bacteriocins of isolated bacteria was separated via SDS-PAGE. Each isolated protein band was characterized and checked for its efficacy in controlling two pathogenic isolates of Xcc via disk diffusion assay. The effects of varieties of carbon, nitrogen and phosphate sources were evaluated on both bacterial growth and bacteriocin production via Taguchi orthogonal method. RESULTS: The two bacteriocins showed an activity up to 55ºC that were sensitive to proteases suggesting being protein in nature. Analysis of SDS-PAGE purified protein bands of bacterial secretomes with demonstrated potency against Xcc revealed the presence of peptides with relative molecular masses of 16.9 and 17 kDa for Cronobacter and Enterobacter, respectively. Sequence analysis of peptides revealed an HCP1 family VI secretion system homologue for Cronobacter (YP_001439956) and pilin FimA homologue for Enterobacter (CBK85798.1). A Taguchi orthogonal array was also implemented to determine the effect of temperature and eight other chemical factors on bacteriocin production for each bacterium. CONCLUSIONS: Two peptides with novel antibacterial activities effective against Xcc were isolated, characterized and conditions were optimized for their higher production.
BACKGROUND:Xanthomonas citri subsp. citri (Xcc), the causative agent of bacterial citrus canker, has affected citriculture worldwide. Varieties of means have been used to minimize its devastating effects, but no attention has been given to bacteriocins. OBJECTIVES: Here and for the first time, we report the isolation and characterization of two novel bacteriocins. MATERIALS AND METHODS: Secretome containing bacteriocins of isolated bacteria was separated via SDS-PAGE. Each isolated protein band was characterized and checked for its efficacy in controlling two pathogenic isolates of Xcc via disk diffusion assay. The effects of varieties of carbon, nitrogen and phosphate sources were evaluated on both bacterial growth and bacteriocin production via Taguchi orthogonal method. RESULTS: The two bacteriocins showed an activity up to 55ºC that were sensitive to proteases suggesting being protein in nature. Analysis of SDS-PAGE purified protein bands of bacterial secretomes with demonstrated potency against Xcc revealed the presence of peptides with relative molecular masses of 16.9 and 17 kDa for Cronobacter and Enterobacter, respectively. Sequence analysis of peptides revealed an HCP1 family VI secretion system homologue for Cronobacter (YP_001439956) and pilin FimA homologue for Enterobacter (CBK85798.1). A Taguchi orthogonal array was also implemented to determine the effect of temperature and eight other chemical factors on bacteriocin production for each bacterium. CONCLUSIONS: Two peptides with novel antibacterial activities effective against Xcc were isolated, characterized and conditions were optimized for their higher production.
Entities:
Keywords:
Bacteriocin; Biocontrol; Protein sequencing; Taguchi orthogonal array; Xanthomonas citri
Authors: Abdelhamid Jabrane; Ahmed Sabri; Philippe Compère; Philippe Jacques; Isabel Vandenberghe; Jozef Van Beeumen; Philippe Thonart Journal: Appl Environ Microbiol Date: 2002-11 Impact factor: 4.792