Unknown,Transcriptomics,Genomics,Proteomics

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Transcriptome analysis of probiotic Lactobacillus casei Zhang during fermentation in soymilk

ABSTRACT: 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.

ORGANISM(S): Lactobacillus casei str. Zhang

SUBMITTER: Heping Zhang

PROVIDER: E-GEOD-23652 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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