Reviewed, UniProtKB/Swiss-Prot P29921 (NQO9_PARDE)

Names and origin

Protein names

Recommended name:
    NADH-quinone oxidoreductase subunit 9
    EC=1.6.99.5
Alternative name(s):
    NADH dehydrogenase I subunit 9
    NDH-1 subunit 9

Gene names

Name:

nqo9

Organism

Paracoccus denitrificans

Taxonomic identifier

266 [NCBI]

Taxonomic lineage

Bacteria › Proteobacteria › Alphaproteobacteria › Rhodobacterales › Rhodobacteraceae › Paracoccus

Protein attributes

Sequence length	163 AA.
Sequence status	Complete.
Protein existence	Inferred from homology.

General annotation (Comments)

Function	NDH-1 shuttles electrons from NADH, via FMN and iron-sulfur (Fe-S) centers, to quinones in the respiratory chain. The immediate electron acceptor for the enzyme in this species is believed to be ubiquinone. Couples the redox reaction to proton translocation (for every two electrons transferred, four hydrogen ions are translocated across the cytoplasmic membrane), and thus conserves the redox energy in a proton gradient. HAMAP MF_01351
Catalytic activity	NADH + quinone = NAD+ + quinol. HAMAP MF_01351
Cofactor	Binds 2 4Fe-4S clusters per subunit By similarity. HAMAP MF_01351
Subunit structure	NDH-1 is composed of at least 14 different subunits, nqo1 to nqo14. The complex has a L-shaped structure, with the hydrophobic arm (subunits nqo7, nqo8, nqo10 to nqo14) embedded in the inner membrane and the hydrophilic peripheral arm (subunits nqo1 to nqo6, nqo9) protruding into the bacterial cytoplasm. The hydrophilic domain contains all the redox centers. HAMAP MF_01351
Subcellular location	Cell inner membrane; Peripheral membrane protein HAMAP MF_01351.
Sequence similarities	Belongs to the complex I 23 kDa subunit family. Contains 2 4Fe-4S ferredoxin-type domains.

Ontologies

Keywords
Cellular component	Cell inner membrane Cell membrane Membrane
Domain	Repeat
Ligand	4Fe-4S Iron Iron-sulfur Metal-binding NAD Ubiquinone
Molecular function	Oxidoreductase
PTM	Quinone
Gene Ontology (GO)
Biological process	oxidation reduction Inferred from electronic annotation. Source: HAMAP photosynthesis, light reaction Inferred from electronic annotation. Source: HAMAP
Cellular component	extrinsic to membrane Inferred from electronic annotation. Source: UniProtKB-SubCell plasma membrane Inferred from electronic annotation. Source: UniProtKB-KW
Molecular function	4 iron, 4 sulfur cluster binding Inferred from electronic annotation. Source: UniProtKB-KW NADH dehydrogenase (quinone) activity Inferred from electronic annotation. Source: EC electron carrier activity Inferred from electronic annotation. Source: InterPro iron ion binding Inferred from electronic annotation. Source: HAMAP quinone binding Inferred from electronic annotation. Source: UniProtKB-KW
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 163	163	NADH-quinone oxidoreductase subunit 9 HAMAP MF_01351		PRO_0000118720
Regions
	Domain	54 – 84	31	4Fe-4S ferredoxin-type 1
	Domain	94 – 123	30	4Fe-4S ferredoxin-type 2
Sites
	Metal binding	64	1	Iron-sulfur 1 (4Fe-4S) By similarity
	Metal binding	67	1	Iron-sulfur 1 (4Fe-4S) By similarity
	Metal binding	70	1	Iron-sulfur 1 (4Fe-4S) By similarity
	Metal binding	74	1	Iron-sulfur 2 (4Fe-4S) By similarity
	Metal binding	103	1	Iron-sulfur 2 (4Fe-4S) By similarity
	Metal binding	106	1	Iron-sulfur 2 (4Fe-4S) By similarity
	Metal binding	109	1	Iron-sulfur 2 (4Fe-4S) By similarity
	Metal binding	113	1	Iron-sulfur 1 (4Fe-4S) By similarity

Sequences

	Sequence		Length	Mass (Da)
	P29921-1 [UniParc]. Last modified April 1, 1993. Version 1. Checksum: 71163CEA824B2475	FASTA	163	18,960
	10 20 30 40 50 60 MAFDFARATK YFLMWDFIKG FGLGMRYFVS PKPTLNYPHE KGPLSPRFRG EHALRRYPNG 70 80 90 100 110 120 EERCIACKLC EAVCPAQAIT IDAERREDGS RRTTRYDIDM TKCIYCGFCQ EACPVDAIVE 130 140 150 160 GPNFEYATET REELFYDKQK LLANGERWEA EIARNLQLDA PYR

References

[1]

"DNA sequencing of the seven remaining structural genes of the gene cluster encoding the energy-transducing NADH-quinone oxidoreductase of Paracoccus denitrificans." Xu X., Matsuno-Yagi A., Yagi T. Biochemistry 32:968-981(1993) [PubMed: 8422400] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA]. Strain: ATCC 13543 / NRRL B-3784.

Cross-references

Sequence databases
EMBL GenBank DDBJ	L02354 Genomic DNA. Translation: AAA25593.1.
PIR	D45456.
3D structure databases
SMR	P29921. Positions 37-153.
ModBase	Search...
Protein family/group databases
TCDB	3.D.1.2.1. H+ or Na+-translocating NADH dehydrogenase (NDH) family.
Enzyme and pathway databases
BRENDA	1.6.99.5. 59.
Family and domain databases
HAMAP	MF_01351. NDH1_NuoI. [Tree]
InterPro	IPR017896. 4Fe4S_Fe-S-bd. IPR017900. 4Fe4S_Fe_S_CS. IPR009051. Helical_ferredxn. IPR010226. NADH_quinone_OxRdtase_chainI. [Graphical view]
TIGRFAMs	TIGR01971. NuoI. 1 hit.
PROSITE	PS00198. 4FE4S_FER_1. 2 hits. PS51379. 4FE4S_FER_2. 2 hits. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

NQO9_PARDE

Accession

Primary (citable) accession number: P29921

Entry history

Integrated into UniProtKB/Swiss-Prot:	April 1, 1993
Last sequence update:	April 1, 1993
Last modified:	February 9, 2010
This is version 71 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HAMAP (High-quality Automated and Manual Annotation of microbial Proteomes)