Project description:Lactobacillus casei Zhang is a probiotic bacterium isolated from koumiss in Inner Mongolia of China. Gene expression dynamics of L. casei Zhang during growth in soymilk was investigated in attempt to reveal the mechanisms involved in growth stimulation for growing probiotics in. Comparison of different transcripts next to each other revealed 162 and 63 significantly induced genes in late logarithmic phase and stationary phase, of which the expression was at least 3 fold up-regulated and down-regulated, respectively. Approximately, 38.4% of the up-regulated genes were associated with amino acid transport and metabolism notably for histidine and lysine biosynthesis, followed by genes/gene clusters involved in carbohydrate transport and metabolism, lipid transport and metabolism, and inorganic ion transport and metabolism. The analysis results suggest that the stimulatory effect of soymilk-based ecosystem on the L. casei Zhang growth is more complex than amino acids or oligopeptides supply.
Project description:Lactobacillus casei Zhang is a probiotic bacterium isolated from koumiss in Inner Mongolia of China that has been commercially used as a starter in the manufacture of dairy products. To study the gene expression profiles of L. casei Zhang during growth in milk, a whole-genome microarray was used. Compared to L. casei Zhang grown to late logarithmic phase in milk, 61 genes were significantly up-regulated (>5 fold) in stationary phase, whereas 26 genes were down-regulated. Collectively, these data showed that the majority of the identified genes was involved in carbohydrate metabolism and energy production, followed by genes involved in nucleotide metabolism, inorganic ion transport, amino acid transport and metabolism, chaperone, etc. This study demonstrates the fundamental effects of cultural conditions on the transcriptome of L. casei Zhang. Moreover, it improves the understanding of the growth and survival mechanism of the bacterium during the late stage of milk fermentation.
Project description:Lactobacillus casei Zhang is a probiotic bacterium isolated from koumiss in Inner Mongolia of China. Gene expression dynamics of L. casei Zhang during growth in soymilk was investigated in attempt to reveal the mechanisms involved in growth stimulation for growing probiotics in. Comparison of different transcripts next to each other revealed 162 and 63 significantly induced genes in late logarithmic phase and stationary phase, of which the expression was at least 3 fold up-regulated and down-regulated, respectively. Approximately, 38.4% of the up-regulated genes were associated with amino acid transport and metabolism notably for histidine and lysine biosynthesis, followed by genes/gene clusters involved in carbohydrate transport and metabolism, lipid transport and metabolism, and inorganic ion transport and metabolism. The analysis results suggest that the stimulatory effect of soymilk-based ecosystem on the L. casei Zhang growth is more complex than amino acids or oligopeptides supply. To study gene expression dynamics of L. casei Zhang during growth in soymilk, a whole genome microarray was used to screen for differentially expressed genes when grown to lag phase, late logarithmic phase, and stationary phase.
Project description:Lactobacillus casei Zhang is a probiotic bacterium isolated from koumiss in Inner Mongolia of China that has been commercially used as a starter in the manufacture of dairy products. To study the gene expression profiles of L. casei Zhang during growth in milk, a whole-genome microarray was used. Compared to L. casei Zhang grown to late logarithmic phase in milk, 61 genes were significantly up-regulated (>5 fold) in stationary phase, whereas 26 genes were down-regulated. Collectively, these data showed that the majority of the identified genes was involved in carbohydrate metabolism and energy production, followed by genes involved in nucleotide metabolism, inorganic ion transport, amino acid transport and metabolism, chaperone, etc. This study demonstrates the fundamental effects of cultural conditions on the transcriptome of L. casei Zhang. Moreover, it improves the understanding of the growth and survival mechanism of the bacterium during the late stage of milk fermentation. L. casei Zhang was grown in milk for 14h (late logarithmic phase) or 18h (stationary phase). 2 biological replicates each.