The Involvement of Nitric Oxide in the Inhibition of the Phosphoroclastic System in Clostridium sporogenes by Sodium Nitrite

Abstract

The phosphoroclastic system was demonstrated in cell-free extracts of clostridium sporogenes by the production of carbon dioxide, acetyl phosphate, ATP and reduced NAD in the presence of pyruvate. The kinetics of acetyl phosphate production and NAD reduction were investigated. The addition of sodium nitrite to a suspension of C. sporogenes in glucose medium resulted in a rapid decrease in intracellular ATP concentration which was accompanied by an accumulation of pyruvate in the medium. This accumulation of pyruvate was caused by inhibition of phosphoroclastic system by nitrate. Nitrite inhibits this system by reaction of nitric oxide, formed from nitrate, with the non-haem iron of pyruvate:ferredoxin oxidoreductase.

Electron paramagnetic resonance spectroscopic investigation of the inhibition of the phosphoroclastic system of Clostridium sporogenes by nitrite

“…It was concluded that the inhibition of the phosphoroclastic system of C. sporogenes by nitrite involved the reduction of nitrite to nitric oxide, and that inhibition was likely to occur by attachment to the non-haem iron centres present in ferredoxin and pyruvate-ferredoxin oxidoreductase. Pyruvate-ferredoxin oxidoreductase activity was inhibited to a greater extent than ferredoxin activity (Woods et al, 1981). The activity of ferredoxin, in an NADH-linked assay, as electron acceptor from pyruvate-ferredoxin oxidoreductase was unaffected by preincubation with 6 mM-sodium nitrite.…”

“…The inhibition of this system would be an effective way of inhibiting spore germination and cell growth. Woods et al (1981) found that when nitrite was added to a suspension of C. sporogenes cells in glucose medium, it resulted in a decrease in intracellular ATP and an accumulation of pyruvate in the medium. Similarly in C. botulinum cells, nitrite caused a decrease in intracellular ATP (Woods & Wood, 1982).…”

“…1966; Perigo et al, 1967;Perigo & Roberts, 1968;BairdParker & Baillie, 1973;O'Leary & Solberg, 1976;Woods et al, 1981;Woods & Wood, 1982). The bacteriostatic action of NaN02 in these systems is enhanced when it is reduced by ascorbate (Tompkin et al, 1978a, b ;Pierson & Smoot, 1981).…”

Anti-microbial Action against VerotoxigenicEscherichia coliO157:H7 of Nitric Oxide Derived from Sodium Nitrite

“…22) Woods et al 8) have reported a finding suggesting such a mechanism, including the formation of a small but detectable amount of NO after the addition of nitrite to a cell-free system. Although the modification of the iron-sulfur centers certainly resulted in an antibacterial effect, the addition of NaNO 2 may have exerted other inhibitory actions.…”

“…NaNO 2 inhibits the phosphoroclastic reaction, and is presumably catalyzed by ferredoxin in Clostridium sporogenes and Clostridium botulinum. 8) Reddy et al 9) have reported that iron-sulfur proteins were contained in vegetative cells of C. botulinum and reacted with NaNO 2 that has been added to form iron-NO complexes, resulting in destruction of the ironsulfur clusters. Inactivation of iron-sulfur enzymes (e.g.…”