cells were grown for at least one day in low pH media. The time resolved expression profile of the S. meliloti 1021 exo genes and flagellar genes following a shift to acidic pH Overall the number of differentially expressed genes belonging to the group of EPS I biosynthesis genes and to the group of genes involved in flagellar biosynthesis and motility is striking. Most exo genes were joined together in cluster B whereas most flagellar genes were grouped together in cluster F. Furthermore, it is noticeable
that the expression of the two groups of genes displayed oppositional characteristics. The EPS I biosynthesis Fosbretabulin research buy genes responded with a fast then constant induction for the duration of the time course, whereas the flagellar genes were increasingly down-regulated. For A. tumefaciens a similar response in succession to pH stress could be identified [50]. In case of A. tumefaciens the transcriptome profiling was performed after 7 hours of growth in low pH. Also in our experiment the expressional characteristics of the exo and flagellar genes indicated that
their response to acidic pH conditions lasts longer than the monitored period of one hour. The regulator coding gene chvI was with most of the exo genes distributed to cluster B. Like in A. tumefaciens the gene chvI was up-regulated together with several genes Salubrinal mw responsible for the succinoglycan biosynthesis [50], although it is believed that chvI is a negative regulator of the exo genes [51]. A closer view on the individual expression levels of the genes of the EPS I biosynthesis gene cluster on pSymB during the time course (Fig. 4) reveals the high induction levels for
the majority of the exo genes. The maximum induction in the observation to period was always reached at 63 minutes after pH shift. Besides the eight exo genes found in cluster B, three exo genes grouped in cluster A and C. The exo genes in cluster A (exoV and exoH) were among the strongest up-regulated genes in this experiment. The products of these genes are responsible for the final steps of the EPS I biosynthesis. They are involved in the succinylation and pyruvilation of EPS I. It could already be shown for S. meliloti that a mutant {Selleck Anti-diabetic Compound Library|Selleck Antidiabetic Compound Library|Selleck Anti-diabetic Compound Library|Selleck Antidiabetic Compound Library|Selleckchem Anti-diabetic Compound Library|Selleckchem Antidiabetic Compound Library|Selleckchem Anti-diabetic Compound Library|Selleckchem Antidiabetic Compound Library|Anti-diabetic Compound Library|Antidiabetic Compound Library|Anti-diabetic Compound Library|Antidiabetic Compound Library|Anti-diabetic Compound Library|Antidiabetic Compound Library|Anti-diabetic Compound Library|Antidiabetic Compound Library|Anti-diabetic Compound Library|Antidiabetic Compound Library|Anti-diabetic Compound Library|Antidiabetic Compound Library|Anti-diabetic Compound Library|Antidiabetic Compound Library|Anti-diabetic Compound Library|Antidiabetic Compound Library|Anti-diabetic Compound Library|Antidiabetic Compound Library|buy Anti-diabetic Compound Library|Anti-diabetic Compound Library ic50|Anti-diabetic Compound Library price|Anti-diabetic Compound Library cost|Anti-diabetic Compound Library solubility dmso|Anti-diabetic Compound Library purchase|Anti-diabetic Compound Library manufacturer|Anti-diabetic Compound Library research buy|Anti-diabetic Compound Library order|Anti-diabetic Compound Library mouse|Anti-diabetic Compound Library chemical structure|Anti-diabetic Compound Library mw|Anti-diabetic Compound Library molecular weight|Anti-diabetic Compound Library datasheet|Anti-diabetic Compound Library supplier|Anti-diabetic Compound Library in vitro|Anti-diabetic Compound Library cell line|Anti-diabetic Compound Library concentration|Anti-diabetic Compound Library nmr|Anti-diabetic Compound Library in vivo|Anti-diabetic Compound Library clinical trial|Anti-diabetic Compound Library cell assay|Anti-diabetic Compound Library screening|Anti-diabetic Compound Library high throughput|buy Antidiabetic Compound Library|Antidiabetic Compound Library ic50|Antidiabetic Compound Library price|Antidiabetic Compound Library cost|Antidiabetic Compound Library solubility dmso|Antidiabetic Compound Library purchase|Antidiabetic Compound Library manufacturer|Antidiabetic Compound Library research buy|Antidiabetic Compound Library order|Antidiabetic Compound Library chemical structure|Antidiabetic Compound Library datasheet|Antidiabetic Compound Library supplier|Antidiabetic Compound Library in vitro|Antidiabetic Compound Library cell line|Antidiabetic Compound Library concentration|Antidiabetic Compound Library clinical trial|Antidiabetic Compound Library cell assay|Antidiabetic Compound Library screening|Antidiabetic Compound Library high throughput|Anti-diabetic Compound high throughput screening| strain of exoH is sensitive to low pH [52], indicating a particular impact of exoH on the pH tolerance and of the EPS I biosynthesis genes on the pH tolerance in general. The higher expression value of exoH compared to other exo genes might also be caused by its position as the first gene in a large operon (exoHKLAMONP) [53]. The central genes of this operon (exoA and exoM) did not show a significant change in their expression level during the time course in contrast to the bordering genes. This might be caused by mRNA instability and degradation effects.