Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:3.2.1.23 (
beta-galactosidase
)
14,648
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Studies on the induction of the
manganese-containing superoxide dismutase
in several strains of Escherichia coli with different mutations in recA and lexA revealed that the inductions of the Mn-isozyme and of the SOS system by oxygen free radicals are not coregulated. We also studied the synthesis of the manganese-superoxide dismutase in the temperature-dependent, protease-constitutive strain recA441(tif-1) that also contained a lac fusion in an SOS gene. A shift to the temperature at which recA441 has constitutive protease activity did not induce Mn-superoxide dismutase but did induce
beta-galactosidase
. The data clearly demonstrate that induction of the Mn-superoxide dismutase is independent of the SOS system.
...
PMID:Regulation of the manganese-containing superoxide dismutase is independent of the inducible DNA repair system in Escherichia coli. 299 50
The Fur protein, which regulates iron uptake in Escherichia coli, also represses the biosynthesis of the
manganese-containing superoxide dismutase
(
MnSOD
). A strain of E. coli bearing a lacZ fusion to the aerobactin operon was used to compare the metal specificities of the regulation of
MnSOD
and of aerobactin by Fur. Iron, but not manganese, acted as a corepressor of the Fur-dependent inhibition of
MnSOD
biosynthesis. The iron-mediated inhibition of
MnSOD
biosynthesis was dependent upon an intact fur locus, indicating that the effect of iron is mediated by the fur gene product. The suppression of the accumulation of
MnSOD
by iron, but not by manganese, was not due to destabilization of the
MnSOD
polypeptide by iron. Thus this effect of iron was also seen in a sodA::lacZ operon fusion in which the production of
beta-galactosidase
was regulated by the sodA promoter. In contrast, both iron and manganese served as corepressors of aerobactin biosynthesis. It thus appears that the effectiveness of specific metal cations to act as corepressors with Fur varies with the gene being regulated by the Fur-metal complex.
...
PMID:Iron specificity of the Fur-dependent regulation of the biosynthesis of the manganese-containing superoxide dismutase in Escherichia coli. 844 93
