P00459 (NIFH1_AZOVI) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Nitrogenase iron protein 1
EC=1.18.6.1

Alternative name(s):
Nitrogenase Fe protein 1
Nitrogenase component II
Nitrogenase reductase

Gene names

Name:

nifH1

Organism

Azotobacter vinelandii

Taxonomic identifier

354 [NCBI]

Taxonomic lineage

cellular organisms › Bacteria › Proteobacteria › Gammaproteobacteria › Pseudomonadales › Pseudomonadaceae › Azotobacter group › Azotobacter

Protein attributes

Sequence length	290 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at protein level

General annotation (Comments)

Function	The key enzymatic reactions in nitrogen fixation are catalyzed by the nitrogenase complex, which has 2 components: the iron protein (component 2) and a component 1 which is either a molybdenum-iron protein, a vanadium-iron, or an iron-iron protein. HAMAP-Rule MF_00533
Catalytic activity	8 reduced ferredoxin + 8 H+ + N2 + 16 ATP + 16 H2O = 8 oxidized ferredoxin + H2 + 2 NH3 + 16 ADP + 16 phosphate. HAMAP-Rule MF_00533
Cofactor	Binds 1 4Fe-4S cluster per dimer.
Subunit structure	Homodimer.
Post-translational modification	The reversible ADP-ribosylation of Arg-101 inactivates the nitrogenase reductase and regulates nitrogenase activity By similarity. HAMAP-Rule MF_00533
Miscellaneous	This subunit is associated with the molybdenum-iron nitrogenase component 2. HAMAP-Rule MF_00533
Sequence similarities	Belongs to the NifH/BchL/ChlL family.

Ontologies

Keywords
Biological process	Nitrogen fixation
Ligand	4Fe-4S ATP-binding Iron Iron-sulfur Metal-binding Nucleotide-binding
Molecular function	Oxidoreductase
PTM	ADP-ribosylation
Technical term	3D-structure Direct protein sequencing
Gene Ontology (GO)
Biological_process	nitrogen fixation Inferred from electronic annotation. Source: HAMAP
Cellular_component	molybdenum-iron nitrogenase complex Inferred from electronic annotation. Source: InterPro
Molecular_function	4 iron, 4 sulfur cluster binding Inferred from electronic annotation. Source: UniProtKB-KW ATP binding Inferred from electronic annotation. Source: HAMAP carbonyl sulfide nitrogenase activity Inferred from electronic annotation. Source: EC metal ion binding Inferred from electronic annotation. Source: UniProtKB-KW nitrogenase activity Inferred from electronic annotation. Source: HAMAP
Complete GO annotation...

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Feature identifier

Molecule processing

Initiator methionine

1

1

Removed Ref.3

Chain

2 – 290

289

Nitrogenase iron protein 1 HAMAP-Rule MF_00533

PRO_0000139490

Regions

Nucleotide binding

10 – 17

8

ATP HAMAP-Rule MF_00533

Sites

Metal binding

98

1

Iron-sulfur (4Fe-4S); shared with dimeric partner

Metal binding

133

1

Iron-sulfur (4Fe-4S); shared with dimeric partner

Amino acid modifications

Modified residue

101

1

ADP-ribosylarginine; by dinitrogenase reductase ADP-ribosyltransferase By similarity

Experimental info

Mutagenesis

16

1

K → Q or P: Loss of nitrogen fixation. Ref.5

Sequence conflict

145

1

A → P in AAA22142. Ref.2

Secondary structure

1

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290

Helix Strand Turn

Details...

Beta strand

4 – 10

7

Helix

12 – 14

3

Helix

16 – 29

14

Beta strand

34 – 39

6

Beta strand

41 – 43

3

Turn

44 – 46

3

Helix

47 – 50

4

Beta strand

52 – 54

3

Helix

58 – 63

6

Beta strand

65 – 67

3

Helix

68 – 70

3

Helix

73 – 76

4

Beta strand

77 – 80

4

Helix

81 – 83

3

Beta strand

85 – 88

4

Turn

94 – 96

3

Helix

99 – 112

14

Helix

115 – 117

3

Beta strand

121 – 128

8

Helix

129 – 131

3

Turn

134 – 137

4

Helix

138 – 141

4

Beta strand

147 – 152

6

Helix

156 – 173

18

Beta strand

179 – 186

8

Beta strand

188 – 190

3

Helix

193 – 204

12

Beta strand

208 – 212

5

Helix

216 – 223

8

Helix

228 – 231

4

Beta strand

233 – 235

3

Helix

236 – 250

15

Helix

262 – 271

10

Helix

280 – 282

3

Turn

287 – 289

3

Sequences

	Sequence		Length	Mass (Da)
	P00459 [UniParc]. Last modified January 23, 2007. Version 2. Checksum: C36EFC0D9A27F64D	FASTA	290	31,516
	10 20 30 40 50 60 MAMRQCAIYG KGGIGKSTTT QNLVAALAEM GKKVMIVGCD PKADSTRLIL HSKAQNTIME 70 80 90 100 110 120 MAAEAGTVED LELEDVLKAG YGGVKCVESG GPEPGVGCAG RGVITAINFL EEEGAYEDDL 130 140 150 160 170 180 DFVFYDVLGD VVCGGFAMPI RENKAQEIYI VCSGEMMAMY AANNISKGIV KYANSGSVRL 190 200 210 220 230 240 GGLICNSRNT DREDELIIAL ANKLGTQMIH FVPRDNVVQR AEIRRMTVIE YDPKAKQADE 250 260 270 280 290 YRALARKVVD NKLLVIPNPI TMDELEELLM EFGIMEVEDE SIVGKTAEEV

References

[1]	"Physical and genetic map of the major nif gene cluster from Azotobacter vinelandii." Jacobson M.R., Brigle K.E., Bennett L.T., Setterquist R.A., Wilson M.S., Cash V.L., Beynon J., Newton W.E., Dean D.R. J. Bacteriol. 171:1017-1027(1989) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[2]	"Complete nucleotide sequence of the Azotobacter vinelandii nitrogenase structural gene cluster." Brigle K.E., Newton W.E., Dean D.R. Gene 37:37-44(1985) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[3]	"The amino acid sequence of the nitrogenase iron protein from Azotobacter vinelandii." Hausinger R.P., Howard J.B. J. Biol. Chem. 257:2483-2490(1982) [PubMed] [Europe PMC] [Abstract] Cited for: PROTEIN SEQUENCE OF 2-290.
[4]	"Sequence of a 1.4 kb Eco RI fragment of Azotobacter vinelandii nif DNA." Hiratsuka K., Roy K.L. Nucleic Acids Res. 16:1207-1207(1988) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 271-290. Strain: ATCC 13705 / OP1 / DSM 366 / NCIB 11614 / LMG 3878 / UW.
[5]	"Mapping the site(s) of MgATP and MgADP interaction with the nitrogenase of Azotobacter vinelandii. Lysine 15 of the iron protein plays a major role in MgATP interaction." Seefeldt L.C., Morgan T.V., Dean D.R., Mortenson L.E. J. Biol. Chem. 267:6680-6688(1992) [PubMed] [Europe PMC] [Abstract] Cited for: MUTAGENESIS OF LYS-16.
[6]	"Crystallographic structure of the nitrogenase iron protein from Azotobacter vinelandii." Georgiadis M.M., Komiya H., Chakrabarti P., Woo D., Kornuc J.J., Rees D.C. Science 257:1653-1659(1992) [PubMed] [Europe PMC] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.9 ANGSTROMS).
[7]	"Structure of ADP x [AlF(4)](-)-stabilized nitrogenase complex and its implications for signal transduction." Schindelin H., Kisker C., Schlessman J.L., Howard J.B., Rees D.C. Nature 387:370-376(1997) [PubMed] [Europe PMC] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (3.0 ANGSTROMS).
[8]	"Conformational variability in structures of the nitrogenase iron proteins from Azotobacter vinelandii and Clostridium pasteurianum." Schlessman J.L., Woo D., Joshua-Tor L., Howard J.B., Rees D.C. J. Mol. Biol. 280:669-685(1998) [PubMed] [Europe PMC] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.2 ANGSTROMS).
[9]	"Insights into nucleotide signal transduction in nitrogenase: structure of an iron protein with MgADP bound." Jang S.B., Seefeldt L.C., Peters J.W. Biochemistry 39:14745-14752(2000) [PubMed] [Europe PMC] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.15 ANGSTROMS).
[10]	"Crystal structure of the all-ferrous [4Fe-4S]0 form of the nitrogenase iron protein from Azotobacter vinelandii." Strop P., Takahara P.M., Chiu H., Angove H.C., Burgess B.K., Rees D.C. Biochemistry 40:651-656(2001) [PubMed] [Europe PMC] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.2 ANGSTROMS).
[11]	"MgATP-bound and nucleotide-free structures of a nitrogenase protein complex between the Leu 127Delta-Fe-protein and the MoFe-protein." Chiu H.-J., Peters J.W., Lanzilotta W.N., Ryle M.J., Seefeldt L.C., Howard J.B., Rees D.C. Biochemistry 40:641-650(2001) [PubMed] [Europe PMC] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.2 ANGSTROMS).
+	Additional computationally mapped references.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ

M20568 Genomic DNA. Translation: AAA64709.1.
M11579 Genomic DNA. Translation: AAA22142.1.
X06886 Genomic DNA. Translation: CAA30003.1.

PIR

NIAVF. A94666.

3D structure databases

PDBe
RCSB PDB
PDBj

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1DE0	X-ray	2.40	A/B	2-289	[»]
1FP6	X-ray	2.15	A/B/C/D	2-290	[»]
1G1M	X-ray	2.25	A/B	2-290	[»]
1G20	X-ray	2.20	E/F/G/H	1-290	[»]
1G21	X-ray	3.00	E/F/G/H	1-290	[»]
1G5P	X-ray	2.20	A/B	2-290	[»]
1M1Y	X-ray	3.20	E/F/G/H/M/N/O/P	2-289	[»]
1M34	X-ray	2.30	E/F/G/H/M/N/O/P	2-290	[»]
1N2C	X-ray	3.00	E/F/G/H	2-290	[»]
1NIP	X-ray	2.90	A/B	2-290	[»]
1RW4	X-ray	2.50	A	3-272	[»]
1XCP	X-ray	3.20	A/B/C/D	2-289	[»]
1XD8	X-ray	2.70	A/B	2-289	[»]
1XD9	X-ray	2.80	A/B	2-289	[»]
1XDB	X-ray	2.80	A/B	2-289	[»]
2AFH	X-ray	2.10	E/F	2-289	[»]
2AFI	X-ray	3.10	E/F/G/H/M/N/O/P	2-289	[»]
2AFK	X-ray	2.30	E/F/G/H	2-289	[»]
2C8V	X-ray	2.50	A	2-290	[»]
2NIP	X-ray	2.20	A/B	2-290	[»]

ProteinModelPortal

P00459.

SMR

P00459. Positions 2-290.

ModBase

Search...

Protocols and materials databases

StructuralBiologyKnowledgebase

Search...

Enzyme and pathway databases

BioCyc

MetaCyc:MONOMER-16519.

Family and domain databases

HAMAP

MF_00533. NifH.

InterPro

IPR000392. Nitogenase_NifH/Reductase_ChlL.
IPR005977. Nitrogenase_Fe_NifH.
[Graphical view]

Pfam

PF00142. Fer4_NifH. 1 hit.
[Graphical view]

PIRSF

PIRSF000363. Nitrogenase_iron. 1 hit.

PRINTS

PR00091. NITROGNASEII.

TIGRFAMs

TIGR01287. nifH. 1 hit.

PROSITE

PS00746. NIFH_FRXC_1. 1 hit.
PS00692. NIFH_FRXC_2. 1 hit.
PS51026. NIFH_FRXC_3. 1 hit.
[Graphical view]

ProtoNet

Search...

Other

EvolutionaryTrace

P00459.

Entry information

Entry name

NIFH1_AZOVI

Accession

Primary (citable) accession number: P00459

Entry history

Integrated into UniProtKB/Swiss-Prot:	July 21, 1986
Last sequence update:	January 23, 2007
Last modified:	April 3, 2013
This is version 111 of the entry and version 2 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Prokaryotic Protein Annotation Program