EC Number   |
Substrates |
Organism |
Products |
Reversibility |
|---|
   1.8.1.18 | more |
PF1186 is formerly proposed to function as a NAD(P)H-dependent CoA-S-S-CoA reductase (CoADR) gene (EC 1.8.1.14). The specific activity for CoA-S-S-CoA reduction (0.006 mol CoA-S-S-CoA reduced/min/mg) is about 20fold lower than the activity that this enzyme exhibits in the S(0) reduction assay. The formeryly reported CoADR activity represents only a partial reaction of its true physiological function, which is now proposed to be CoA-dependent S(0) reduction |
Pyrococcus furiosus |
? |
- |
? |
| 1.8.1.18 | polysulfide(n) + NADPH + H+ |
- |
Pyrococcus furiosus |
hydrogen sulfide + polysulfide(n-1) + NADP+ |
- |
? |
| 1.8.1.18 | polysulfide(n) + NADPH + H+ |
NADH can not replace NADPH, the purified recombinant enzyme catalyzes the reduction of polysulfide with NADPH as an electron donor and it also reduces oxygen |
Thermococcus litoralis |
hydrogen sulfide + polysulfide(n-1) + NADP+ |
- |
? |
| 1.8.1.18 | polysulfide(n) + NADPH + H+ |
NADH can not replace NADPH, the purified recombinant enzyme catalyzes the reduction of polysulfide with NADPH as an electron donor and it also reduces oxygen |
Thermococcus litoralis DSM 5473 |
hydrogen sulfide + polysulfide(n-1) + NADP+ |
- |
? |
| 1.8.1.18 | sulfur + NAD(P)H + H+ |
- |
Thermococcus kodakarensis |
hydrogen sulfide + NAD(P)+ |
- |
? |
| 1.8.1.18 | sulfur + NAD(P)H + H+ |
the rate of sulfide production from colloidal sulfur is linear (up to 10 min) suggesting that this is the true substrate for the enzyme. A lag phase in sulfide production would be expected if polysulfide, which is generated by the reaction of sulfide with elemental sulfur, is the natural substrate. A less-than-twofold increase in activity is observed, both at pH 7.0 and at pH 9.0, when polysulfide (11 mM) is used as the substrate compared to when elemental sulfur (6.4 g/liter) is used. Polysulfide is stable at pH 8 and readily dissociates to colloidal sulfur and sulfide at neutral pH. A much greater stimulation of activity would be observed if polysulfide is the preferred substrate, particularly at the higher pH |
Pyrococcus furiosus |
hydrogen sulfide + NAD(P)+ |
- |
? |
| 1.8.1.18 | sulfur + NAD(P)H + H+ |
a catalytic cycle of TK1299 is proposed suggesting that CoA-SH acts to solubilize S(0) by forming CoA persulfides, followed by reduction of an enzyme-S-S-CoA intermediate produced after both enzymatic and non-enzymatic evolution of H2S from the CoA persulfide, with NADPH as an electron donor |
Thermococcus kodakarensis |
hydrogen sulfide + NAD(P)+ |
- |
? |
| 1.8.1.18 | sulfur + NADH + H+ |
colloidal sulfur generated from polysulfide is a better substrate than the elemental sulfur. The sulfur reductase activity requires anaerobic conditions (the product sulfide is oxidized by oxygen) |
Pyrococcus furiosus |
hydrogen sulfide + NAD+ |
- |
? |
| 1.8.1.18 | sulfur + NADPH + H+ |
colloidal sulfur generated from polysulfide is a better substrate than the elemental sulfur. The sulfur reductase activity requires anaerobic conditions (the product sulfide is oxidized by oxygen) |
Pyrococcus furiosus |
hydrogen sulfide + NADP+ |
- |
? |
