Induction of superoxide dismutases in Escherichia coli by manganese and iron

Journal Article · Mon Oct 01 00:00:00 EDT 1984 · J. Bacteriol.; (United States)

OSTI ID:6264240

Pugh, S Y.R.; DiGuiseppi, J L; Fridovich, I

Growth of Escherichia coli B in simple media enriched with Mn(II) resulted in the elevation of the manganese-containing superoxide dismutase, whereas growth in such medium enriched with iron caused increased content of the iron-containing superoxide dismutase. Enrichment of the medium with Co(II), Cu(II), Mo(VI), Zn(II), or Ni(II) had no effect. The inductions of superoxide dismutase by Mn(II) or by Fe(II) were dioxygen dependent, but these metals did not affect the CN/sup -/-resistant respiration of E. coli B and did not influence the increase in the CN/sup -/-resistant respiration caused by paraquat. Mn(II) and paraquat acted synergistically in elevating the superoxide dismutase content, and Mn(II) reduced the growth inhibition imposed by paraquat. E. coli grown in the complex 3% Trypticase soy broth (BBL Microbiology Systems)-0.5% yeast extract-0.2% glucose medium contained more superoxide dismutase than did cells grown in the simple media and were less responsive to enrichment of the medium with Mn(II) or Fe(II). Nevertheless, in the presence of paraquat, induction of superoxide dismutase by these metals could be seen even in the Trypticase-yeast extract-glucose medium. On the basis of these observations, the authors propose that the apo-superoxide dismutases may act as autogenous repressors and that Mn(II) and Fe(II) increase the cell content of the corresponding enzymes by speeding the conversion of the apo- to the holoenzymes.

• Research Organization: Duke Univ. Medical Center, Durham, NC
• OSTI ID: 6264240
• Journal Information: J. Bacteriol.; (United States), Vol. 160:1
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
COBALT
BIOLOGICAL EFFECTS
COPPER
ESCHERICHIA COLI
GROWTH
IRON
MANGANESE
MOLYBDENUM
NICKEL
SUPEROXIDE DISMUTASE
ENZYME ACTIVITY
ZINC
CELL CULTURES
SYNERGISM
BACTERIA
ELEMENTS
ENZYMES
METALS
MICROORGANISMS
OXIDOREDUCTASES
TRANSITION ELEMENTS
560302* - Chemicals Metabolism & Toxicology- Microorganisms- (-1987)