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Literature summary for 1.1.1.363 extracted from

  • Szweda, L.I.; Stadtman, E.R.
    Iron-catalyzed oxidative modification of glucose-6-phosphate dehydrogenase from Leuconostoc mesenteroides. Structural and functional changes (1992), J. Biol. Chem., 267, 3096-3100.
    View publication on PubMed

Inhibitors

Inhibitors Comment Organism Structure
Fe2+ the enzyme is rapidly inactivated by micromolar concentrations of Fe2+ and H2O2. Inactivation correlates with the formation of one carbonyl functionality/enzyme subunit, indicating that inactivation is the result of site-specific oxidative modification. Fe2+ binds to the glucose 6-phosphate binding site and interaction of the enzyme-bound Fe2+ with H2O2 leads to the oxidative modification of amino acids essential for enzyme activity. Partially inactivated enzyme remains predominantly in the dimeric form, and no change in the apparent affinity of the remaining active subunits for substrate is observed. Partial inactivation leads to a decrease in the thermal stability of the remaining activity. This decrease in thermal stability could be largely overcome by the addition of glucose 6-phosphate. Thus, although exposure to H2O2 and Fe2+ results in the irreversible inactivation of the enzyme, the resulting modification is selective, leads to the formation of heterodimers of both active and inactive subunits, and does not appear to cause large scale structural changes Leuconostoc mesenteroides
H2O2 the enzyme is rapidly inactivated by micromolar concentrations of Fe2+ and H2O2. Inactivation correlates with the formation of one carbonyl functionality/enzyme subunit, indicating that inactivation is the result of site-specific oxidative modification. Fe2+ binds to the glucose 6-phosphate binding site and interaction of the enzyme-bound Fe2+ with H2O2 leads to the oxidative modification of amino acids essential for enzyme activity. Partially inactivated enzyme remains predominantly in the dimeric form, and no change in the apparent affinity of the remaining active subunits for substrate is observed. Partial inactivation leads to a decrease in the thermal stability of the remaining activity. This decrease in thermal stability could be largely overcome by the addition of glucose 6-phosphate. Thus, although exposure to H2O2 and Fe2+ results in the irreversible inactivation of the enzyme, the resulting modification is selective, leads to the formation of heterodimers of both active and inactive subunits, and does not appear to cause large scale structural changes Leuconostoc mesenteroides

Organism

Organism UniProt Comment Textmining
Leuconostoc mesenteroides
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-
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Synonyms

Synonyms Comment Organism
Glu-6-PDH
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Leuconostoc mesenteroides

Temperature Stability [°C]

Temperature Stability Minimum [°C] Temperature Stability Maximum [°C] Comment Organism
additional information
-
the enzyme is rapidly inactivated by micromolar concentrations of Fe2+ and H2O2. Fe2+ binds to the glucose 6-phosphate binding site and interaction of the enzyme-bound Fe2+ with H2O2 leads to the oxidative modification of amino acids essential for enzyme activity. Partially inactivated enzyme remains predominantly in the dimeric form, and no change in the apparent affinity of the remaining active subunits for substrate is observed. Partial inactivation leads to a decrease in the thermal stability of the remaining activity. This decrease in thermal stability could be largely overcome by the addition of glucose 6-phosphate. Thus, although exposure to H2O2 and Fe2+ results in the irreversible inactivation of the enzyme, the resulting modification is selective, leads to the formation of heterodimers of both active and inactive subunits, and does not appear to cause large scale structural changes Leuconostoc mesenteroides