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Information on EC 1.7.2.7 - hydrazine synthase
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EC Tree
1.7.2.7 hydrazine synthaseIUBMB Comments
The enzyme, characterized from anaerobic ammonia oxidizers (anammox bacteria), is one of only a few enzymes that are known to form an N-N bond (other examples include EC 1.7.1.14, nitric oxide reductase [NAD(P)+, nitrous oxide-forming] and EC 4.8.1.1, L-piperazate synthase). The enzyme from the bacterium Candidatus Kuenenia stuttgartiensis is a dimer of heterotrimers and contains multiple c-type cytochromes.
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Word Map
- 1.7.2.7
-
anammox
- nitrite
-
candidatus
- brocadia
- kuenenia
-
wastewater
-
ammonium-oxidizing
-
dinitrogen
- stuttgartiensis
-
wetland
-
denitrification
- scalindua
- planctomycetes
- jettenia
-
ladderane
-
influent
- anammoxosome
-
paddy
- sinica
- fulgida
- diagnostics
The expected taxonomic range for this enzyme is: Archaea, Eukaryota, Bacteria
Reaction Schemes
Synonyms
hydrazine synthase, hzsabc, 
more
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SYNONYM 
ORGANISM
UNIPROT
COMMENTARY 
LITERATURE
HZS
hzsA
hzsABC
hzsB
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REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT
LITERATURE
hydrazine + H2O + 3 ferricytochrome c = nitric oxide + ammonium + 3 ferrocytochrome c
-
-
-
-
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SYSTEMATIC NAME
IUBMB Comments
hydrazine:ferricytochrome-c oxidoreductase
The enzyme, characterized from anaerobic ammonia oxidizers (anammox bacteria), is one of only a few enzymes that are known to form an N-N bond (other examples include EC 1.7.1.14, nitric oxide reductase [NAD(P)+, nitrous oxide-forming] and EC 4.8.1.1, L-piperazate synthase). The enzyme from the bacterium Candidatus Kuenenia stuttgartiensis is a dimer of heterotrimers and contains multiple c-type cytochromes.
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SUBSTRATE
PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate)
(Substrate)
LITERATURE
(Substrate)
(Substrate)
COMMENTARY
(Product)
(Product)
LITERATURE
(Product)
(Product)
Reversibility
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
nitric oxide + ammonium + 3 H+
hydrazine + H2O
-
-
-
?
hydrazine + H2O + ferricytochrome c
nitric oxide + ammonium + ferrocytochrome c
-
-
-
-
?
hydrazine + H2O + ferricytochrome c
nitric oxide + ammonium + ferrocytochrome c
-
-
-
-
?
hydrazine + H2O + ferricytochrome c
nitric oxide + ammonium + ferrocytochrome c
-
-
-
-
?
hydrazine + H2O + ferricytochrome c
nitric oxide + ammonium + ferrocytochrome c
-
-
-
-
?
hydrazine + H2O + ferricytochrome c
nitric oxide + ammonium + ferrocytochrome c
-
-
-
-
?
hydrazine + H2O + ferricytochrome c
nitric oxide + ammonium + ferrocytochrome c
-
-
-
-
?
hydrazine + H2O + ferricytochrome c
nitric oxide + ammonium + ferrocytochrome c
-
-
-
-
?
hydrazine + H2O + ferricytochrome c
nitric oxide + ammonium + ferrocytochrome c
-
-
-
?
hydrazine + H2O + ferricytochrome c
nitric oxide + ammonium + ferrocytochrome c
-
-
-
-
?
hydrazine + H2O + ferricytochrome c
nitric oxide + ammonium + ferrocytochrome c
-
-
-
-
?
nitric oxide + ammonium + 3 ferrocytochrome c
hydrazine + H2O + 3 ferricytochrome c
-
-
-
-
?
nitric oxide + ammonium + 3 ferrocytochrome c
hydrazine + H2O + 3 ferricytochrome c
-
-
-
-
?
nitric oxide + ammonium + 3 ferrocytochrome c
hydrazine + H2O + 3 ferricytochrome c
-
-
-
-
?
nitric oxide + ammonium + 3 ferrocytochrome c
hydrazine + H2O + 3 ferricytochrome c
-
-
-
-
?
nitric oxide + ammonium + 3 ferrocytochrome c
hydrazine + H2O + 3 ferricytochrome c
-
-
-
?
additional information
?
-
-
the bacterial Ca. Jettenia caeni strain reduces NO3- to NH4+ with the oxidation of acetate and accumulates hydrazine in the culture with the consumption of hydroxylamine. The predominant menaquinone is MK-7
-
-
?
additional information
?
-
-
the bacterial Ca. Jettenia caeni strain reduces NO3- to NH4+ with the oxidation of acetate and accumulates hydrazine in the culture with the consumption of hydroxylamine. The predominant menaquinone is MK-7
-
-
?
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NATURAL SUBSTRATE
NATURAL PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate)
(Substrate)
LITERATURE
(Substrate)
(Substrate)
COMMENTARY
(Product)
(Product)
LITERATURE
(Product)
(Product)
REVERSIBILITY
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
nitric oxide + ammonium + 3 H+
hydrazine + H2O
-
-
-
?
hydrazine + H2O + ferricytochrome c
nitric oxide + ammonium + ferrocytochrome c
-
-
-
-
?
hydrazine + H2O + ferricytochrome c
nitric oxide + ammonium + ferrocytochrome c
-
-
-
-
?
hydrazine + H2O + ferricytochrome c
nitric oxide + ammonium + ferrocytochrome c
-
-
-
-
?
hydrazine + H2O + ferricytochrome c
nitric oxide + ammonium + ferrocytochrome c
-
-
-
-
?
hydrazine + H2O + ferricytochrome c
nitric oxide + ammonium + ferrocytochrome c
-
-
-
-
?
hydrazine + H2O + ferricytochrome c
nitric oxide + ammonium + ferrocytochrome c
-
-
-
-
?
hydrazine + H2O + ferricytochrome c
nitric oxide + ammonium + ferrocytochrome c
-
-
-
-
?
hydrazine + H2O + ferricytochrome c
nitric oxide + ammonium + ferrocytochrome c
-
-
-
?
hydrazine + H2O + ferricytochrome c
nitric oxide + ammonium + ferrocytochrome c
-
-
-
-
?
hydrazine + H2O + ferricytochrome c
nitric oxide + ammonium + ferrocytochrome c
-
-
-
-
?
nitric oxide + ammonium + 3 ferrocytochrome c
hydrazine + H2O + 3 ferricytochrome c
-
-
-
-
?
nitric oxide + ammonium + 3 ferrocytochrome c
hydrazine + H2O + 3 ferricytochrome c
-
-
-
-
?
nitric oxide + ammonium + 3 ferrocytochrome c
hydrazine + H2O + 3 ferricytochrome c
-
-
-
-
?
nitric oxide + ammonium + 3 ferrocytochrome c
hydrazine + H2O + 3 ferricytochrome c
-
-
-
-
?
nitric oxide + ammonium + 3 ferrocytochrome c
hydrazine + H2O + 3 ferricytochrome c
-
-
-
?
additional information
?
-
-
the bacterial Ca. Jettenia caeni strain reduces NO3- to NH4+ with the oxidation of acetate and accumulates hydrazine in the culture with the consumption of hydroxylamine. The predominant menaquinone is MK-7
-
-
?
additional information
?
-
-
the bacterial Ca. Jettenia caeni strain reduces NO3- to NH4+ with the oxidation of acetate and accumulates hydrazine in the culture with the consumption of hydroxylamine. The predominant menaquinone is MK-7
-
-
?
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COFACTOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
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METALS and IONS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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SPECIFIC ACTIVITY [µmol/min/mg]
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
0.33
-
Ca. Jettenia caeni cells, pH not specified in the publication, 37°C
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ORGANISM
COMMENTARY
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
strain KSU-1 is enriched from activated sludge collected from a wastewater treatment plant installed in the Kumamoto city, Japan
-
-
brenda
strain KSU-1 is enriched from activated sludge collected from a wastewater treatment plant installed in the Kumamoto city, Japan
-
-
brenda
from the in situ microbial community in an oligotrophic, brackish environment of the Bothnian Sea sediment
-
-
brenda
subunits alpha, beta and gamma
UniProt
brenda
subunits HzsA, HzsB and HzsC
UniProt
brenda
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SOURCE TISSUE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
SOURCE
additional information
additional information
-
planctomycete KSU-1 cells show high expression levels of hydrazine synthase
brenda
additional information
-
planctomycete KSU-1 cells show high expression levels of hydrazine synthase
-
brenda
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LOCALIZATION
ORGANISM
UNIPROT
COMMENTARY
GeneOntology No.
LITERATURE
SOURCE
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GENERAL INFORMATION
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
evolution
physiological function
evolution
for ammonia-oxidizing bacteria, a major shift from Candidatus Brocadia fulgida to Candidatus Kuenenia stuttgartiensis in both suspension and biofilm was observed with progressively shorter HRT, using discriminatory biomarkers targeting the hydrazine synthase (hzsA) gene is determined in biofilm analysis. Directed differentiation between the biofilm and suspension is observed in the molecular microbial ecology and gene expression of different bacteria in a biofilm nitritation-anammox process operates at varying hydraulic residence times and nitrogen loading rates
evolution
for ammonia-oxidizing bacteria, a major shift from Candidatus Brocadia fulgida to Candidatus Kuenenia stuttgartiensis in both suspension and biofilm was observed with progressively shorter HRT, using discriminatory biomarkers targeting the hydrazine synthase (hzsA) gene is determined in biofilm analysis. Directed differentiation between the biofilm and suspension is observed in the molecular microbial ecology and gene expression of different bacteria in a biofilm nitritation-anammox process operates at varying hydraulic residence times and nitrogen loading rates
evolution
-
metagenomic analysis of diagnostic genes encoding key enzymes involved in the nitrogen cycle in in situ microbial community in an oligotrophic, brackish environment of the Bothnian Sea sediment, overview. Metagenome analysis reveals higher hzsA gene read abundance in sulfate methane transition zone (SMTZ, 2.4) than in oxic/anoxic interface zone (OAZ, 0.6). The hza sequences show high similarity to uncultured Scalindua spp. originating from the marine sediments in Guyamas Basin (AGV76990)
physiological function
-
hydrazine biosynthesis is catalysed by enzyme Hzs. The cells metabolize hydrazine as an intermediate of the anammox process. Hydrazine biosynthesis from NH4+ and hydroxylamine, hydrazine accumulates in the culture concurrently with consumption of hydroxylamine. Hydrazine accumulation continues until hydroxylamine is depleted. Thereafter, hydrazine concentration gradually decreases. Ca. Jettenia caeni cells synthesize hydrazine with the consumption of hydroxylamine
physiological function
-
hydrazine biosynthesis is catalysed by enzyme Hzs. The cells metabolize hydrazine as an intermediate of the anammox process. Hydrazine biosynthesis from NH4+ and hydroxylamine, hydrazine accumulates in the culture concurrently with consumption of hydroxylamine. Hydrazine accumulation continues until hydroxylamine is depleted. Thereafter, hydrazine concentration gradually decreases. Ca. Jettenia caeni cells synthesize hydrazine with the consumption of hydroxylamine
-
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UNIPROT
ENTRY NAME
ORGANISM
NO. OF AA
NO. OF TRANSM. HELICES
MOLECULAR WEIGHT[Da]
SOURCE
SEQUENCE
LOCALIZATION PREDICTION
The reliability class of the localization prediction ranges from 1 (very reliable) to 5 (not reliable).
The reliability class of the localization prediction ranges from 1 (very reliable) to 5 (not reliable). A0A8K1PHD0_9BACT
428
0
47927
TrEMBL
-
A0A8K1PHT2_9BACT
428
0
47874
TrEMBL
-
A0A8K1PI86_9BACT
428
0
47819
TrEMBL
-
A0A8K1PH66_9BACT
429
0
48117
TrEMBL
-
A0A8K1PII7_9BACT
428
0
47900
TrEMBL
-
A0A8K1UFT7_9BACT
428
0
47849
TrEMBL
-
A0A8K1UFU2_9BACT
428
0
47921
TrEMBL
-
A0A8K1PHE1_9BACT
428
0
47944
TrEMBL
-
A0A8K1UFM1_9BACT
428
0
47964
TrEMBL
-
A0A8K1UFU4_9BACT
428
0
47890
TrEMBL
-
A0A8K1PH63_9BACT
428
0
47917
TrEMBL
-
A0A8K1PHC8_9BACT
428
0
47803
TrEMBL
-
A0A8K1PI80_9BACT
428
0
47975
TrEMBL
-
A0A8K1PII2_9BACT
428
0
47898
TrEMBL
-
A0A8K1PHU0_9BACT
428
0
47918
TrEMBL
-
A0A8K1PII1_9BACT
428
0
48007
TrEMBL
-
A0A8K1PHB2_9BACT
428
0
47886
TrEMBL
-
A0A8K1UFT8_9BACT
428
0
47862
TrEMBL
-
A0A8K1PHC3_9BACT
428
0
47886
TrEMBL
-
A0A8K1PHB7_9BACT
428
0
47807
TrEMBL
-
A0A8K1PHC9_9BACT
428
0
47797
TrEMBL
-
A0A8K1UFY9_9BACT
428
0
47801
TrEMBL
-
A0A8K1PIK4_9BACT
428
0
47870
TrEMBL
-
A0A8K1UFZ5_9BACT
428
0
47916
TrEMBL
-
G9ITI7_9BACT
773
0
86618
TrEMBL
Chloroplast (Reliability: 3)
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MOLECULAR WEIGHT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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SUBUNIT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
heterotrimer
heterotrimer
1 * 90000 + 2 * 42000 + 1 * 39000, subunits HzsA + HzsC + HzsB, SDS-PAGE
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CRYSTALLIZATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
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PURIFICATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
Q Sepharose column chromatography, hydroxyapatite column chromatography and Superose 6 gel filtration
-
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CLONED (Commentary)
ORGANISM
UNIPROT
LITERATURE
gene hzsA, cloned from the in situ microbial community in an oligotrophic, brackish environment of the Bothnian Sea sediment, DNA and amino acid sequence determination and analysis, sequence comparisons. The sequence shows high similarity to uncultured Scalindua spp. originating from the marine sediments in Guyamas Basin (AGV76990)
-
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EXPRESSION
ORGANISM
UNIPROT
LITERATURE
a nitrite shock of 500 mg leads to a decrease in mRNA level
-
nitrite shocks of up to 400 mg lead to an increase in mRNA level
-
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APPLICATION
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
diagnostics
diagnostics
gene hzsA, encoding hydrazine synthase, is used as a biomarker for differentiation of biofilms and suspension, lab scale nitritation-anammox reactor with Kaldnes K1 carriers. Discrimination between Candidatus Brocadia fulgida and Candidatus Kuenenia stuttgartiensis based on hydrazine synthase subunit A (hzsA)
diagnostics
gene hzsA, encoding hydrazine synthase, is used as a biomarker for differentiation of biofilms and suspension, lab scale nitritation-anammox reactor with Kaldnes K1 carriers. Discrimination between Candidatus Brocadia fulgida and Candidatus Kuenenia stuttgartiensis based on hydrazine synthase subunit A (hzsA)
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REF.
AUTHORS
TITLE
JOURNAL
VOL.
PAGES
YEAR
ORGANISM (UNIPROT)
PUBMED ID
SOURCE
Harhangi, H.R.; Le Roy, M.; van Alen, T.; Hu, B.L.; Groen, J.; Kartal, B.; Tringe, S.G.; Quan, Z.X.; Jetten, M.S.; Op den Camp, H.J.
Hydrazine synthase, a unique phylomarker with which to study the presence and biodiversity of anammox bacteria
Appl. Environ. Microbiol.
78
752-758
2012
Candidatus Brocadia anammoxidans, Candidatus Kuenenia stuttgartiensis, Candidatus Brocadia fulgida, Candidatus Anammoxoglobus propionicus, Candidatus Scalindua
brenda
Guo, J.; Peng, Y.; Fan, L.; Zhang, L.; Ni, B.J.; Kartal, B.; Feng, X.; Jetten, M.S.; Yuan, Z.
Metagenomic analysis of anammox communities in three different microbial aggregates
Environ. Microbiol.
18
2979-2993
2016
Candidatus Kuenenia, Candidatus Brocadia
brenda
Oshiki, M.; Ali, M.; Shinyako-Hata, K.; Satoh, H.; Okabe, S.
Hydroxylamine-dependent anaerobic ammonium oxidation (anammox) by Candidatus Brocadia sinica
Environ. Microbiol.
18
3133-3143
2016
Candidatus Brocadia sinica
brenda
Wang, Y.; Ma, X.; Zhou, S.; Lin, X.; Ma, B.; Park, H.D.; Yan, Y.
Expression of the nirS, hzsA, and hdh genes in response to nitrite shock and recovery in Candidatus Kuenenia stuttgartiensis
Environ. Sci. Technol.
50
6940-6947
2016
Candidatus Kuenenia stuttgartiensis
brenda
Wang, Y.; Zhu, G.; Harhangi, H.R.; Zhu, B.; Jetten, M.S.; Yin, C.; Op den Camp, H.J.
Co-occurrence and distribution of nitrite-dependent anaerobic ammonium and methane-oxidizing bacteria in a paddy soil
FEMS Microbiol. Lett.
336
79-88
2012
Candidatus Brocadia anammoxidans, Candidatus Jettenia asiatica, Candidatus Brocadia fulgida
brenda
de Almeida, N.M.; Neumann, S.; Mesman, R.J.; Ferousi, C.; Keltjens, J.T.; Jetten, M.S.; Kartal, B.; van Niftrik, L.
Immunogold localization of key metabolic enzymes in the anammoxosome and on the tubule-like structures of Kuenenia stuttgartiensis
J. Bacteriol.
197
2432-2441
2015
Candidatus Kuenenia stuttgartiensis (Q1Q0T2), Candidatus Kuenenia stuttgartiensis
brenda
Kartal, B.; Maalcke, W.; De Almeida, N.; Cirpus, I.; Gloerich, J.; Geerts, W.; Op Den Camp, H.; Harhangi, H.; Janssen-Megens, E.; Francoijs, K.; Stunnenberg, H.; Keltjens, J.; Jetten, M.; Strous, M.
Molecular mechanism of anaerobic ammonium oxidation
Nature
479
127-130
2011
Candidatus Kuenenia stuttgartiensis (Q1Q0T2)
brenda
Dietl, A.; Ferousi, C.; Maalcke, W.J.; Menzel, A.; de Vries, S.; Keltjens, J.T.; Jetten, M.S.; Kartal, B.; Barends, T.R.
The inner workings of the hydrazine synthase multiprotein complex
Nature
527
394-397
2015
Candidatus Kuenenia stuttgartiensis (Q1Q0T2), Candidatus Kuenenia stuttgartiensis
brenda
Wang, S.; Peng, Y.; Ma, B.; Wang, S.; Zhu, G.
Anaerobic ammonium oxidation in traditional municipal wastewater treatment plants with low-strength ammonium loading: Widespread but overlooked
Water Res.
84
66-75
2015
Candidatus Kuenenia, Candidatus Brocadia
brenda
Park, H.; Sundar, S.; Ma, Y.; Chandran, K.
Differentiation in the microbial ecology and activity of suspended and attached bacteria in a nitritation-anammox process
Biotechnol. Bioeng.
112
272-279
2015
Candidatus Brocadia fulgida (G9ITI7), Candidatus Kuenenia stuttgartiensis (Q1Q0T2)
brenda
Ali, M.; Oshiki, M.; Awata, T.; Isobe, K.; Kimura, Z.; Yoshikawa, H.; Hira, D.; Kindaichi, T.; Satoh, H.; Fujii, T.; Okabe, S.
Physiological characterization of anaerobic ammonium oxidizing bacterium Candidatus Jettenia caeni
Environ. Microbiol.
17
2172-2189
2015
Candidatus Jettenia caeni, Candidatus Jettenia caeni KSU-1
brenda
Rasigraf, O.; Schmitt, J.; Jetten, M.S.M.; Lueke, C.
Metagenomic potential for and diversity of N-cycle driving microorganisms in the Bothnian Sea sediment
MicrobiologyOpen
6
e475
2017
uncultured bacterium
brenda
Su, J.; Chen, S.
A key piece in the global N-cycle The N-N bond formation presented by heme-dependent hydrazine synthase
ACS Catal.
11
6489-6498
2021
Candidatus Kuenenia stuttgartiensis (Q1Q0T2 and Q1Q0T4 and Q1Q0T3)
-
brenda
Akram, M.; Dietl, A.; Mueller, M.; Barends, T.R.M.
Purification of the key enzyme complexes of the anammox pathway from DEMON sludge
Biopolymers
112
e23428
2021
Candidatus Brocadia fulgida
brenda
Yang, Y.; Li, M.; Li, X.; Gu, J.
Two identical copies of the hydrazine synthase gene clusters found in the genomes of anammox bacteria
Int. Biodeter. Biodegrad.
132
236-240
2018
Candidatus Kuenenia stuttgartiensis, Candidatus Brocadia fulgida, Candidatus Brocadia sinica, Candidatus Brocadia caroliniensis
-
brenda
Akram, M.; Reimann, J.; Dietl, A.; Menzel, A.; Versantvoort, W.; Kartal, B.; Jetten, M.S.M.; Barends, T.R.M.
A nitric oxide-binding heterodimeric cytochrome c complex from the anammox bacterium Kuenenia stuttgartiensis binds to hydrazine synthase
J. Biol. Chem.
294
16712-16728
2019
Candidatus Kuenenia stuttgartiensis (Q1Q0T2 and Q1Q0T4 and Q1Q0T3), Candidatus Kuenenia stuttgartiensis
brenda
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Release 2023.1 (January 2023)
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