As seen here and reported previously [ 28, 29], the configuration of an operon greatly affects the expression of its genes.
The E. coli Lrp is the best-studied member of the Lrp family, a global regulator in E. coli affecting the expression of many genes and operons [31].
These data indicated that the virB operon may control the intracellular survival of Brucella by affecting the expression of relevant proteins.
We have shown that H37Ra has a 58 bp repeat DNA insertion in the putative promoter region of the lpdA-glpD2 operon, which could affect the expression of both LpdA and GlpD2.
It is known that BOX insertions can affect the expression of nearby genes [ 16, 17]; another example where they might impact on the transcription of an operon is upstream of the trp gene cluster.
Two other genes in the rck operon, pefI and srgA, appear to affect the expression and function of the pef operon which encodes socalled plasmid-encoded fimbriae [ 9, 11, 12].
The down-regulation of virulence gene expression is partly caused by the repression of saeRS, but also the decreased expression of the agr operon affects their low expression.
Using the artificial operon system, the expression of P450 BM3 reached 81 mg g−1 cell dry weight.
Activation of the LEE1 operon leads to the expression of Ler, which activates the other LEE genes in operons LEE2 to LEE5 and several cistrons.
Since the operon structure affects the regulation of gene expression, operon prediction becomes the first step towards regulatory network reconstruction at the whole genome level.
PqsR is a LysR-type transcriptional regulator that binds to the promoter region of pqsABCDE operon and directly controls the expression of the operon (Cao et al., 2001; Gallagher et al., 2002).
