EC Number   |
General Information |
Reference |
|---|
    1.7.2.1 | evolution |
the copper-containing nitrite reductase is observed in mostly gram negative denitrifying soil bacteria. The microorganisms containing the copper-containing nitrite reductase are typically found in the low oxygen containing environments |
-, 742316 |
| 1.7.2.1 | metabolism |
4-domain variant of enzyme utilizes N-terminal tethering for downregulating enzymatic activity. Tethering communicates the redox state of the heme to the distant type 2 copper center that helps initiate substrate binding for catalysis |
764656 |
| 1.7.2.1 | metabolism |
tethering does not enhance the rate of electron delivery from its pendant cytochrome c to the catalytic copper-containing core. Tethering communicates the redox state of the heme to the distant type 2 copper center that helps initiate substrate binding for catalysis. It also tunes copper reduction potentials, suppresses reductive enzyme inactivation, enhances enzyme affinity for substrate, and promotes inter-copper electron transfer. Nitrite binding and enzyme turnover is controlled by heme reduction and prevents NiR inactivation |
-, 763797 |
| 1.7.2.1 | metabolism |
the driving force for electron transfer from type 1 copper to type 2 copper comes from a remote water-mediated triple-proton-coupled electron-transfer mechanism. In the high-pH proton channel, the water-mediated triple-proton transfer occurs from Glu113 to an intermediate water molecule, whereas in the primary channel, the transfer is from Lys128 to His260. Subsequently, the two channels employ another two or three distinct proton-transfer steps to deliver the proton to the nitrite substrate at the type 2 copper site |
764480 |
| 1.7.2.1 | metabolism |
the enzyme catalyzes the key reaction in denitrification as the nitrogen compound is changed from an ionic state to a gaseous molecule |
-, 742802 |
| 1.7.2.1 | metabolism |
the enzyme is involved in the denitrification anoxic process, which occurs in four reduction steps: initial conversion of nitrate to nitrite, followed by transformation of nitrite to nitric oxide, subsequent reduction of nitric oxide to nitrous oxide, and the final conversion of nitrous oxide to dinitrogen gas. All stages are catalyzed by complex metalloenzymes with different transition metal cofactors. Dissimilatory nitrite reductases (NiRs) catalyze the reduction of nitrite to nitric oxide, the committed step in denitrification. There are two main types: one containing iron (cd1NiRs) and the other copper (CuNiRs) |
741908 |
| 1.7.2.1 | more |
determination of the activation energies, transition states, and minimum energy pathways of CuNiR for reaction mechanism analysis. Structure modelling of the CuNiR active site involving residues His100, His135, His306, Asp98, His255, Ile257 and four water molecules. Structure-function analysis, detailed overview |
741908 |
| 1.7.2.1 | more |
geometric structure of the nitrite-bound T2 Cu site in GtNiR using density functional theory, DFT, calculations. The reduction of T2 Cu site promotes the proton transfer. Optimized structures of nitrite binding forms under physiological pH conditions and in neutral states, detailed overview |
-, 741932 |
| 1.7.2.1 | physiological function |
copper-containing nitrite reductase (CuNIR) catalyzes the reduction of nitrite (NO2 ) to nitric oxide (NO) during denitrification |
-, 742802 |
| 1.7.2.1 | physiological function |
deletion of cytochrome cd1-type nitrite reductase NirS gene or gene NirN results in impaired growth and smaller, fewer, and aberrantly shaped magnetite crystals during nitrate reduction. Nitrite reduction is completely abolished in the DELTAnirS mutant. NirN is required for full reductase activity of NirS by maintaining a proper form of d1 heme for holo-cytochrome cd1 assembly |
725291 |
