Effect of FadR overexpression in an engineered fatty acid overproducer
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ABSTRACT:
ORGANISM(S): Escherichia coli K-12 Escherichia coli
PROVIDER: GSE35392 | GEO | 2012/01/28
SECONDARY ACCESSION(S): PRJNA152695
REPOSITORIES: GEO
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Project description:Transcriptome analysis of strains LT-ΔfadE (control) and FRT-ΔfadE (FadR overexpressor) after 12h of fatty acid production. The strains used are described in detail in Zhang F, M Ouellet, TS Batth, CJ Petzold, A Mukhopadhyay and JD Keasling. Enhancing fatty acid production by the expression of the regulatory transcription factor FadR. (In preparation) Three independent cultures of control strain LT-ΔfadE and four independent cultures of FadR overexpressor strain FRT-ΔfadE were induced. One sample derived from each culture was hybridized.
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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.
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