Project: PRJNA664263
Aim of this study us to comprehensively analyze the genome of seven isolates of four probiotic bacterial species from traditional yogurt samples using the next-generation sequencing approach. Homemade yogurt samples prepared from cow milk were collected in sterile bottles along with ice pack from local vendors in the Karak district of Khyber Pakhtoonkhwa, Pakistan. The yogurt samples were aseptically homogenized and dissolved in phosphate buffered saline (PBS), serially diluted and plated on general Man Rogosa Sharpe (MRS) agar solid plate as well as on selective medium. The selective media used for Lactobacillus delbrueckii were MRS with pH 5.2, MRS-Bile for Lactobacillus casei and paracasei, and MRS Vancomycin for Lactobacillus rhamnosus respectively. Plates were incubated in triplicate under anaerobic conditions at 37 and 45 degree Celsius for 24 to 72 hours. The pure bacterial colonies for each species were isolated using subculture techniques. A single isolated bacterial colony from pure culture of each selected agar plate was grown from 24 to 48 hours on MRS broth, followed by genomic DNA isolation using a Tiangen bacterial DNA isolation kit. The isolated DNA was purified using ethanol precipitation and quantified using Qubit 2 fluorometer. DNA Libraries were generated using Vazyme TruePrep DNA Library Prep Kit V2 for Illumina. Sequencing was performed on an Illumina HiSeq-2000 sequencing platform according to the manufacturer instruction.
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