In a
Salmonella enterica cutR mutant,
E. coli ybaO restored cysteine-responsive regulation of the CdsH cysteine desulfhydrase
[7].
decR is a member of the Rob regulon
[6].
Based on transcript profiling with a
cyuR mutant and overpression of
cyuR under anaerobic cysteine growth conditions, 37 genes showed at least a 5-fold change in expression, with increased expression of 20 genes and diminished expression of 17 genes
[8]. Some of the induced genes included the following: the two most upregulated genes,
cyuP and
cyuA; proteins involved in aromatic amino acid metabolism: two genes of the
tyrA-aroF operon,
aroP, and
aroL; and several genes for proteins involved in carbohydrate metabolism,
lacI, two genes of the
srlA operon, and all the genes of the
uidABC and
dhaKLM operons. Six of the repressed genes degrade glucarate and galacturate:
gudP and the adjacent
garPLRK and
garD operons. Nine of the downregulated genes are in the maltose regulon:
malEFG,
malK-
lamB-
malM,
malPQ, and
malS [8].
DecR regulates cysteine degradation to sulfide. Based on a study with wild-type
E. coli and a
decR mutant, it was determined that a speciation change to Hg(II)-sulfide controls Hg(II) cell association in the presence of excess cysteine
[9]
DecR:"
detoxification of
cysteine
regulator"
[2].
CyuR: "
cysteine
utilization
regulator"
[8]