Reviewed, UniProtKB/Swiss-Prot P29918 (NQO6_PARDE)

Names and origin

Protein names

Recommended name:
    NADH-quinone oxidoreductase subunit 6
    EC=1.6.99.5
Alternative name(s):
    NADH dehydrogenase I subunit 6
    NDH-1 subunit 6

Gene names

Name:

nqo6

Organism

Paracoccus denitrificans

Taxonomic identifier

266 [NCBI]

Taxonomic lineage

Bacteria › Proteobacteria › Alphaproteobacteria › Rhodobacterales › Rhodobacteraceae › Paracoccus

Protein attributes

Sequence length	173 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is not processed.
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_01356
Catalytic activity	NADH + quinone = NAD+ + quinol. HAMAP MF_01356
Cofactor	Binds 1 4Fe-4S cluster Potential.
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_01356
Subcellular location	Cell inner membrane; Peripheral membrane protein; Cytoplasmic side Probable.
Sequence similarities	Belongs to the complex I 20 kDa subunit family.

Ontologies

Keywords
Cellular component	Cell inner membrane Cell membrane Membrane
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	internal side of plasma membrane Inferred from electronic annotation. Source: UniProtKB-SubCell
Molecular function	4 iron, 4 sulfur cluster binding Inferred from electronic annotation. Source: UniProtKB-KW NADH dehydrogenase (ubiquinone) 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 – 173	173	NADH-quinone oxidoreductase subunit 6 HAMAP MF_01356		PRO_0000118762
Sites
	Metal binding	53	1	Iron-sulfur (4Fe-4S) Potential
	Metal binding	54	1	Iron-sulfur (4Fe-4S) Potential
	Metal binding	118	1	Iron-sulfur (4Fe-4S) Potential
	Metal binding	148	1	Iron-sulfur (4Fe-4S) Potential

Sequences

	Sequence		Length	Mass (Da)
	P29918-1 [UniParc]. Last modified April 1, 1993. Version 1. Checksum: 587B86578797CAEF	FASTA	173	19,117
	10 20 30 40 50 60 MTGLNTAGAD RDLATAELNR ELQDKGFLLT TTEDIINWAR NGSLHWMTFG LACCAVEMMQ 70 80 90 100 110 120 TSMPRYDLER FGTAPRASPR QSDLMIVAGT LTNKMAPALR KVYDQMPEPR YVISMGSCAN 130 140 150 160 170 GGGYYHYSYS VVRGCDRIVP VDIYVPGCPP TAEALLYGIL QLQRRASGAP ARW

References

[1]

"Gene cluster of the energy-transducing NADH-quinone oxidoreductase of Paracoccus denitrificans: characterization of four structural gene products." Xu X., Matsuno-Yagi A., Yagi T. Biochemistry 31:6925-6932(1992) [PubMed: 1637825] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA]. Strain: ATCC 13543 / NRRL B-3784.

Cross-references

Sequence databases
EMBLGenBankDDBJ	M93015 Unassigned DNA. Translation: AAA03036.1. Sequence problems.
PIR	E42573.
3D structure databases
ModBase	Search...
Protein family/group databases
TCDB	3.D.1.2.1. proton-translocating NADH dehydrogenase (NDH) family.
Enzyme and pathway databases
BRENDA	1.6.99.5. 59.
Family and domain databases
HAMAP	MF_01356. [Tree]
InterPro	IPR006137. NADH_UbQ_OxRdtase-like_20kDa. IPR006138. NADH_UbQ_OxRdtase_20kDa_su. IPR014406. NiFe_hyd_3_ssu/Q_oxred_NuoB. [Graphical view]
PANTHER	PTHR11995:SF2. NADH_DH_20kDa. 1 hit. PTHR11995. NiFe_hyd_3_ssu/Q_oxred_NuoB. 1 hit.
Pfam	PF01058. Oxidored_q6. 1 hit. [Graphical view]
TIGRFAMs	TIGR01957. nuoB_fam. 1 hit.
PROSITE	PS01150. COMPLEX1_20K. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

NQO6_PARDE

Accession

Primary (citable) accession number: P29918

Entry history

Integrated into UniProtKB/Swiss-Prot:	April 1, 1993
Last sequence update:	April 1, 1993
Last modified:	October 13, 2009
This is version 53 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)