Literature summary for 1.7.2.4 extracted from

Qu, Z.; Bakken, L.R.; Molstad, L.; Frostegard, A.; Bergaust, L.L.
Transcriptional and metabolic regulation of denitrification in Paracoccus denitrificans allows low but significant activity of nitrous oxide reductase under oxic conditions (2016), Environ. Microbiol., 18, 2951-2963 .

Cloned(Commentary)

Cloned (Comment)	Organism
gene nosZ, transcription of nosZ takes place concomitantly with that of narG under suboxic conditions. Catalytically functional N2OR is synthesized and active in aerobically raised cells transferred to vials with 7 vol% O2 in headspace, but N2O reduction rates are 10 times higher when anaerobic precultures are subjected to the same conditions. Upon oxygen exposure, there is an incomplete and transient inactivation of N2OR that can be ascribed to its lower ability to compete for electrons compared with terminal oxidases, quantitative real-time PCR enzyme expression analysis	Paracoccus denitrificans

Cloned (Comment)

Organism

gene nosZ, transcription of nosZ takes place concomitantly with that of narG under suboxic conditions. Catalytically functional N2OR is synthesized and active in aerobically raised cells transferred to vials with 7 vol% O2 in headspace, but N2O reduction rates are 10 times higher when anaerobic precultures are subjected to the same conditions. Upon oxygen exposure, there is an incomplete and transient inactivation of N2OR that can be ascribed to its lower ability to compete for electrons compared with terminal oxidases, quantitative real-time PCR enzyme expression analysis

Paracoccus denitrificans

Inhibitors

Inhibitors	Comment	Organism	Structure
O2	N2OR being more sensitive to O2 than the other N-oxide reductases. The enzyme's apparent inactivation by O2 may be due to changes in the redox state of the unique Cuz-centre found in N2OR	Paracoccus denitrificans

Metals/Ions

Metals/Ions	Comment	Organism	Structure
Cu2+	bound in a Cu centre, dependent on. The state of Cuz in extracted N2OR depends on the conditions during purification. Anoxic purification yields the purple, active form of the enzyme, whereas oxic conditions results in a blue form of N2OR with a redox inert Cuz centre, Cuz*. The blue form of N2OR is catalytically inactive, but may be reactivated in vitro by a strong reductant such as reduced methyl viologen	Paracoccus denitrificans

Natural Substrates/ Products (Substrates)

Natural Substrates	Organism	Comment (Nat. Sub.)	Natural Products	Comment (Nat. Pro.)	Rev.	Reac.
nitrous oxide + 2 reduced cytochrome c	Paracoccus denitrificans	-	nitrogen + H2O + 2 cytochrome c	-	?

Organism

Organism	UniProt	Comment	Textmining
Paracoccus denitrificans	-	-	-

Oxidation Stability

Oxidation Stability	Organism
N2OR being more sensitive to O2 than the other N-oxide reductases. The enzyme's apparent inactivation by O2 may be due to changes in the redox state of the unique Cuz-centre found in N2OR	Paracoccus denitrificans

Source Tissue

Source Tissue	Comment	Organism	Textmining
additional information	gene nosZ, transcription of nosZ takes place concomitantly with that of narG under suboxic conditions. Catalytically functional N2OR is synthesized and active in aerobically raised cells transferred to vials with 7 vol% O2 in headspace, but N2O reduction rates are 10 times higher when anaerobic precultures are subjected to the same conditions. Upon oxygen exposure, there is an incomplete and transient inactivation of N2OR that can be ascribed to its lower ability to compete for electrons compared with terminal oxidases	Paracoccus denitrificans	-

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.	Reac.
additional information	determination of detailed gas kinetics and transcription patterns from batch culture experiments with Paracoccus denitrificans, allowing in vivo estimation of electron flow to O2 and N2O under various O2 regimes	Paracoccus denitrificans	?	-	?
nitrous oxide + 2 reduced cytochrome c	-	Paracoccus denitrificans	nitrogen + H2O + 2 cytochrome c	-	?

Synonyms

Synonyms	Comment	Organism
N2OR	-	Paracoccus denitrificans
nitrous oxide reductase	-	Paracoccus denitrificans
NosZ	-	Paracoccus denitrificans

Cofactor

Cofactor	Comment	Organism	Structure
cytochrome c	-	Paracoccus denitrificans

Expression

Organism	Comment	Expression
Paracoccus denitrificans	aerobically raised cells of Paracoccus denitrificans induce transcription of nosZ immediately after being transferred to intermediate O2 concentration (7 vol% O2 in headspace) in the presence of NO3- resulting in increased catalytically active enzyme levels	up

General Information

General Information	Comment	Organism
physiological function	transcriptional and metabolic regulation of denitrification in Paracoccus denitrificans allows low but significant activity of nitrous oxide reductase under oxic conditions	Paracoccus denitrificans