UV - Induced Mutagenesis in Lactic Acid Bacteria
نویسنده
چکیده
Induced mutagenesis is widely used for selection of microorganisms producing biologically active substances and further improving of their activities. However, it is rarely used toward lactic acid bacteria (LAB) due to their genetic specificity. Determination of LABs sensitivity to UV light and evaluate the effectiveness of UV-induced mutagenesis by positive selection of antibiotic resistant mutants. Bacterial cells grown in LAPTg and NB broth up to late log phase were harvested by centrifugation and resuspended in phosphate buffer (pH 6.8) and irradiated by UV (15 w paired lamps) at distance of 30 cm and plated on LAPTg and NB agars with and without antibiotics for survivors count and positive selection of Rif and Str colonies. It was revealed that lactic acid bacteria were 1 to 2 log more resistant to UV in compression with E. coli. At dose 40 sec the difference in survival between L. lactis and E. coli was not so significant. The yield of rifampicin and streptomycin resistant mutants of LABs vary depending of UV exposure. The maximum yield about 2-3 log of both types of resistant mutants in lactobacilli and lactococcus were observed at dose 20 sec (0.1% survival). LAB possesses intrinsic resistance to UV irradiation 1-2 log higher than E. coli. The maximum yield of UV induced Rif and Str mutants in all LABs occurs at survival about 0.1%. Thus UV rays as an effective mutagen can be used in selection of dairy starters with improved technological and probiotics characteristic.
منابع مشابه
Overproduction of Clavulanic Acid by UV Mutagenesis of Streptomyces clavuligerus
Clavulanic acid is produced industrially by fermentation of Streptomyces clavuligerus and researches have increased its production by strain improvement, recombinant DNA technology, and media composition and growth condition optimization. The main objective of this study was to increase the level of clavulanic acid production from Streptomyces clavuligerus (DSM 738), using UV irradiation. After...
متن کاملOverproduction of Clavulanic Acid by UV Mutagenesis of Streptomyces clavuligerus
Clavulanic acid is produced industrially by fermentation of Streptomyces clavuligerus and researches have increased its production by strain improvement, recombinant DNA technology, and media composition and growth condition optimization. The main objective of this study was to increase the level of clavulanic acid production from Streptomyces clavuligerus (DSM 738), using UV irradiation. After...
متن کاملIdentification of lactic acid bacteria isolated from traditional drinking yoghurt in tribes of Fars province
Morphological, cultural, physiological and biochemical characteristics were employed to identify lactic acid bacteria (LAB), isolated from drinking yoghurt in different areas in Fars province, Iran. From 18 drinking yoghurt samples a total of 673 LAB positives were determined, in which 117 (17.38%) and 556 (82.62%) were identified as lactic acid cocci and lactic acid bacilli, respectively. Addi...
متن کاملBiogenic synthesis and antimicrobial activity of Silver nanoparticle using exopolysaccharides from Lactic Acid bacteria
Nanotechnology provides the ability to engineer the properties of materials by controlling their size, and this has driven research toward a multitude of potential uses for nanomaterials. This study aimed at biosynthesis and characterization of silver nanoparticles (SNPs) using exopolysaccharides (EPS) of lactic acid bacteria (LAB) and the antimicrobial potential of the biosynthesized SNPs agai...
متن کاملBiogenic synthesis and antimicrobial activity of Silver nanoparticle using exopolysaccharides from Lactic Acid bacteria
Nanotechnology provides the ability to engineer the properties of materials by controlling their size, and this has driven research toward a multitude of potential uses for nanomaterials. This study aimed at biosynthesis and characterization of silver nanoparticles (SNPs) using exopolysaccharides (EPS) of lactic acid bacteria (LAB) and the antimicrobial potential of the biosynthesized SNPs agai...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2016