Transcriptional and maturational modulation of the biosynthesis of manganese superoxide dismutase in Escherichia coli by diamide

Conference · Mon Mar 11 04:00:00 EST 1991 · FASEB Journal (Federation of American Societies for Experimental Biology); (United States)

OSTI ID:5374432

Privalle, C T; Fridovich, I ^[1]

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1. Duke Univ., Durham, NC (United States)

Diamide causes an anaerobic induction of active MnSOD in E. coli, which is dependent upon de novo biosynthesis of protein. Anaerobic electron sinks, such as NO{sub 3}{sup {minus}} plus paraquat, which elicit the production of an inactive, incorrectly substituted MnSOD, synergized with diamide in the induction of MnSOD activity; whereas the effect on MnSOD polypeptide was strictly additive, suggestive of diamide-facilitated maturation of nascent MnSOD polypeptide. Diamide, in the presence of IPTG, also caused anaerobic formation of active MnSOD in a tac-sodA operon fusion strain. {sigma}phenanthroline, or Mn(II), also allowed anaerobic accumulation of active MnSOD in this strain, indicative of a competition between iron and manganese in the maturation of MnSOD. Immunoblot analysis showed that Mn(II), {sigma}-phenanthroline, or diamide, caused appearance of a species which co-migrated with Mn{sub 2}-MnSOD. In addition, the rate and extent of anaerobic reconstitution of apoMnSOD with manganous salts were increased by diamide. These results suggest that diamide facilitates anaerobic biosynthesis of active MnSOD by: (a) increasing transcription of the sodA gene, perhaps by oxidative inactivation of a Fe(II)-containing repressor and (b) facilitating insertion of manganese into the nascent MnSOD polypeptide.

• OSTI ID: 5374432
• Report Number(s): CONF-9104107--
• Conference Information: Journal Name: FASEB Journal (Federation of American Societies for Experimental Biology); (United States) Journal Volume: 5:4
• Country of Publication: United States
• Language: English

Related Subjects

560300* -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AMIDES
ANAEROBIC CONDITIONS
BACTERIA
BIOLOGICAL EFFECTS
BIOSYNTHESIS
ELEMENTS
ENZYME ACTIVITY
ENZYMES
ESCHERICHIA COLI
GENES
MANGANESE
METABOLISM
METALS
MICROORGANISMS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXIDOREDUCTASES
PEPTIDES
POLYPEPTIDES
PROTEINS
SUPEROXIDE DISMUTASE
SYNTHESIS
TRANSCRIPTION
TRANSITION ELEMENTS