Activating Compound | Comment | Organism | Structure |
---|---|---|---|
FMN | - |
Cupriavidus necator |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
additional information | release of one FMN reduces the NAD+ reduction by 90%, but is reversible by addition of excess FMN, insensitivity towards oxygen, with all 4 CN- groups bound to the enzyme, and towards CO | Cupriavidus necator | |
O2 | irreversible enzyme inhibition by oxygen occurs if the CN- bound to Ni2+ is irreversibly removed or if the enzyme is reduced by NADH | Cupriavidus necator |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
cytoplasm | - |
Cupriavidus necator | 5737 | - |
soluble | - |
Cupriavidus necator | - |
- |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
CN- | enzyme contains four cyanides in its active site, the Ni2+ bound one is responsible for the insensitivity towards oxygen, the active site is a (enzyme-Cys)2(CN)Ni(micro-enzyme-Cys)2Fe(CN)3(CO) centre, the CN- bound to the nickel ion can be irreversibly removed inducing enzyme inhibition by oxygen | Cupriavidus necator | |
CO | bound to the active site, the active site is a (enzyme-Cys)2(CN)Ni(micro-enzyme-Cys)2Fe(CN)3(CO) centre | Cupriavidus necator | |
cyanide | enzyme contains four cyanides in its active site, one of which is responsible for the insensitivity towards oxygen | Cupriavidus necator | |
Fe2+ | enzyme contains a [Ni-Fe] cluster | Cupriavidus necator | |
Fe2+ | the active site is a (enzyme-Cys)2(CN)Ni(micro-enzyme-Cys)2Fe(CN)3(CO) centre | Cupriavidus necator | |
Ni2+ | enzyme contains a [Ni-Fe] cluster | Cupriavidus necator | |
Ni2+ | the active site is a (enzyme-Cys)2(CN)Ni(micro-enzyme-Cys)2Fe(CN)3(CO) centre, H2 activation solely takes place on Ni2+ | Cupriavidus necator |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
H2 + NAD+ | Cupriavidus necator | - |
H+ + NADH | - |
? | |
H2 + NAD+ | Cupriavidus necator | - |
H+ + NADH | - |
r |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Cupriavidus necator | - |
- |
- |
Cupriavidus necator | - |
facultative lithoautotrophic Knallgas bacterium | - |
Oxidation Stability | Organism |
---|---|
insensitive to O2 | Cupriavidus necator |
insensitivity towards oxygen, irreversible enzyme inhibition by oxygen occurs if the CN- bound to Ni2+ is irreversibly removed or if the enzyme is reduced by NADH | Cupriavidus necator |
Purification (Comment) | Organism |
---|---|
- |
Cupriavidus necator |
Specific Activity Minimum [µmol/min/mg] | Specific Activity Maximum [µmol/min/mg] | Comment | Organism |
---|---|---|---|
additional information | - |
- |
Cupriavidus necator |
17 | 84 | activity of different batches with NAD+ and H2 | Cupriavidus necator |
30 | 100 | purified enzyme, forward reaction under aerobic conditions with NAD+ | Cupriavidus necator |
125 | 175 | activity of different batches with NADH and ferricyanide | Cupriavidus necator |
1263 | - |
activity of different batches with benzyl viologen and H2 | Cupriavidus necator |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
ferrocyanide + NAD+ | - |
Cupriavidus necator | ferricyanide + NADH | - |
r | |
ferrocyanide + NAD+ | diaphorase activity | Cupriavidus necator | ferricyanide + NADH | - |
r | |
H2 + NAD+ | - |
Cupriavidus necator | H+ + NADH | - |
? | |
H2 + NAD+ | - |
Cupriavidus necator | H+ + NADH | - |
r | |
H2 + NAD+ | H2 activation solely takes place on Ni2+ | Cupriavidus necator | H+ + NADH | - |
r | |
H2 + oxidized benzyl viologen | - |
Cupriavidus necator | H+ + reduced benzyl viologen | - |
r | |
H2 + oxidized benzyl viologen | hydrogenase activity | Cupriavidus necator | H+ + reduced benzyl viologen | - |
r | |
additional information | addition of NADH prolonged the lag phase before H2 consumption | Cupriavidus necator | ? | - |
? | |
additional information | FMN release induces reduction with NADH, enzyme shows both hydrogenase and diaphorase activities, proton channeling | Cupriavidus necator | ? | - |
? |
Subunits | Comment | Organism |
---|---|---|
More | subunits HoxHY form a heterodimer which is responsible for the hydrogenase activity, subunits HoxFU form a heterodimer which is responsible for the NADH-dehydrogenase or diaphorase activity | Cupriavidus necator |
tetramer | enzyme is composed of 4 Hox subunits, HoxF, HoxH, HoxU, and HoxY, with MWs of 67 kDa, 55 kDa, 26 kDa, and 23 kDa | Cupriavidus necator |
Synonyms | Comment | Organism |
---|---|---|
NAD+-reducing [NiFe]-hydrogenase | - |
Cupriavidus necator |
SH | - |
Cupriavidus necator |
SH | i.e. soluble cytoplasmic hydrogenase | Cupriavidus necator |
soluble [NiFe]-hydrogenase | - |
Cupriavidus necator |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
30 | - |
assay at | Cupriavidus necator |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
8 | - |
assay at | Cupriavidus necator |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
benzyl viologen | oxidized and reduced | Cupriavidus necator | |
FMN | 2 molecules per enzyme molecule, one of 2 can be reversibly released upon reduction of the enzyme | Cupriavidus necator | |
FMN | required, 2 molecules per tetrameric enzyme complex, reduced enzyme reversibly releases half of the FMN bound, kinetics, FMN release induces reduction with NADH, overview | Cupriavidus necator | |
NAD+ | - |
Cupriavidus necator | |
NADH | - |
Cupriavidus necator |