P53800 (FDFT_NICBE) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names	Recommended name: Squalene synthase Short name=SQS Short name=SS EC=2.5.1.21 Alternative name(s): FPP:FPP farnesyltransferase Farnesyl-diphosphate farnesyltransferase
Organism	Nicotiana benthamiana
Taxonomic identifier	4100 [NCBI]
Taxonomic lineage	Eukaryota › Viridiplantae › Streptophyta › Embryophyta › Tracheophyta › Spermatophyta › Magnoliophyta › eudicotyledons › core eudicotyledons › asterids › lamiids › Solanales › Solanaceae › Nicotianoideae › Nicotianeae › Nicotiana

Protein attributes

Sequence length	411 AA.
Sequence status	Complete.
Protein existence	Evidence at transcript level

General annotation (Comments)

Catalytic activity	2 farnesyl diphosphate = diphosphate + presqualene diphosphate. Presqualene diphosphate + NAD(P)H = squalene + diphosphate + NAD(P)+.
Cofactor	Magnesium By similarity.
Pathway	Terpene metabolism; lanosterol biosynthesis; lanosterol from farnesyl diphosphate: step 1/3.
Subcellular location	Endoplasmic reticulum membrane; Multi-pass membrane protein By similarity.
Sequence similarities	Belongs to the phytoene/squalene synthase family.

Ontologies

Keywords
Biological process	Isoprene biosynthesis
Cellular component	Endoplasmic reticulum Membrane
Domain	Transmembrane Transmembrane helix
Ligand	Magnesium NADP
Molecular function	Oxidoreductase Transferase
Technical term	Multifunctional enzyme
Gene Ontology (GO)
Biological process	isoprenoid biosynthetic process Inferred from electronic annotation. Source: UniProtKB-KW
Cellular component	endoplasmic reticulum membrane Inferred from electronic annotation. Source: UniProtKB-SubCell integral to membrane Inferred from electronic annotation. Source: UniProtKB-KW
Molecular function	farnesyl-diphosphate farnesyltransferase activity Inferred from electronic annotation. Source: EC oxidoreductase activity Inferred from electronic annotation. Source: UniProtKB-KW squalene synthase activity Inferred from electronic annotation. Source: EC
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 411	411	Squalene synthase		PRO_0000067456
Regions
	Transmembrane	281 – 301	21	Helical; Potential
	Transmembrane	388 – 408	21	Helical; Potential

Sequences

	Sequence		Length	Mass (Da)
	P53800 [UniParc]. Last modified October 1, 1996. Version 1. Checksum: 5DE209E9BB70A42A	FASTA	411	47,083
	10 20 30 40 50 60 MGSLRAILKN PEDLYPLVKL KLAARHAEKQ IPPSPNWGFC YSMLHKVSRS FALVIQQLPV 70 80 90 100 110 120 ELRDAVCIFY LVLRALDTVE DDTSIPTDVK VPILISFHQH VYDREWHFSC GTKEYKVLMD 130 140 150 160 170 180 QFHHVSTAFL ELRKHYQQAI EDITMRMGAG MAKFICKEVE TTDDYDEYCH YVAGLVGLGL 190 200 210 220 230 240 SKLFHASEKE DLASDSLSNS MGLFLQKTNI IRDYLEDINE VPKCRMFWPR EIWSKYVNKL 250 260 270 280 290 300 EELKYEDNSA KAVQCLNDMV TNALPHVEDC LTYMSALRDP SIFRFCAIPQ VMAIGTLAMC 310 320 330 340 350 360 YDNIEVFRGV VKMRRGLTAK VIDRTRTIAD VYGAFFDFSC MLKSKVNNND PNATKTLKRL 370 380 390 400 410 EVILKTCRDS GTLNKRKSYI IRSEPNYSPV LIVVIFIILA IILAQLSGNR S

References

[1]	"Molecular cloning, in vitro expression and characterization of a plant squalene synthetase cDNA." Hanley K.M., Nicolas O., Donaldson T.B., Smith-Monroy C., Robinson G.W., Hellmann G.M. Plant Mol. Biol. 30:1139-1151(1996) [PubMed: 8704125] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA].
+	Additional computationally mapped references.

Cross-references

Sequence databases
EMBL GenBank DDBJ	U46000 mRNA. Translation: AAA87048.1.
PIR	S71771.
3D structure databases
ProteinModelPortal	P53800.
ModBase	Search...
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Family and domain databases
InterPro	IPR002060. Squ/phyt_synthse. IPR006449. Squal_synth. IPR019845. Squalene/phytoene_synthase_CS. IPR008949. Terpenoid_synth. [Graphical view]
Gene3D	G3DSA:1.10.600.10. Terpenoid_synth. 1 hit.
Pfam	PF00494. SQS_PSY. 1 hit. [Graphical view]
SUPFAM	SSF48576. Terpenoid_synth. 1 hit.
TIGRFAMs	TIGR01559. Squal_synth. 1 hit.
PROSITE	PS01044. SQUALEN_PHYTOEN_SYN_1. 1 hit. PS01045. SQUALEN_PHYTOEN_SYN_2. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

FDFT_NICBE

Accession

Primary (citable) accession number: P53800

Entry history

Integrated into UniProtKB/Swiss-Prot:	October 1, 1996
Last sequence update:	October 1, 1996
Last modified:	September 21, 2011
This is version 70 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Plant Protein Annotation Program