Q00834 (CYSK_SPIOL) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names	Recommended name: Cysteine synthase EC=2.5.1.47 Alternative name(s): CSase A O-acetylserine (thiol)-lyase Short name=OAS-TL A O-acetylserine sulfhydrylase
Organism	Spinacia oleracea (Spinach)
Taxonomic identifier	3562 [NCBI]
Taxonomic lineage	cellular organisms › Eukaryota › Viridiplantae › Streptophyta › Streptophytina › Embryophyta › Tracheophyta › Euphyllophyta › Spermatophyta › Magnoliophyta › eudicotyledons › core eudicotyledons › Caryophyllales › Amaranthaceae › Spinacia

Protein attributes

Sequence length	325 AA.
Sequence status	Complete.
Protein existence	Evidence at protein level

General annotation (Comments)

Catalytic activity	O(3)-acetyl-L-serine + H2S = L-cysteine + acetate.
Cofactor	Pyridoxal phosphate.
Pathway	Amino-acid biosynthesis; L-cysteine biosynthesis; L-cysteine from L-serine: step 2/2.
Subunit structure	Homodimer.
Subcellular location	Cytoplasm.
Tissue specificity	Leaves and roots.
Post-translational modification	The N-terminus is blocked.
Sequence similarities	Belongs to the cysteine synthase/cystathionine beta-synthase family.

Ontologies

Keywords
Biological process	Amino-acid biosynthesis Cysteine biosynthesis
Cellular component	Cytoplasm
Ligand	Pyridoxal phosphate
Molecular function	Transferase
Technical term	Direct protein sequencing
Gene Ontology (GO)
Biological_process	cysteine biosynthetic process from serine Inferred from electronic annotation. Source: InterPro
Cellular_component	cytoplasm Inferred from electronic annotation. Source: UniProtKB-SubCell
Molecular_function	cysteine synthase activity Inferred from electronic annotation. Source: EC transferase activity 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 – 325	325	Cysteine synthase		PRO_0000167125
Regions
	Region	184 – 188	5	Pyridoxal phosphate binding By similarity
Sites
	Binding site	80	1	Pyridoxal phosphate By similarity
	Binding site	272	1	Pyridoxal phosphate By similarity
Amino acid modifications
	Modified residue	49	1	N6-(pyridoxal phosphate)lysine

Sequences

	Sequence		Length	Mass (Da)
	Q00834 [UniParc]. Last modified April 1, 1993. Version 1. Checksum: 161B46F7B670DEE6	FASTA	325	34,187
	10 20 30 40 50 60 MVEEKAFIAK DVTELIGKTP LVYLNTVADG CVARVAAKLE GMEPCSSVKD RIGFSMITDA 70 80 90 100 110 120 EKSGLITPGE SVLIEPTSGN TGIGLAFIAA AKGYKLIITM PASMSLERRT ILRAFGAELI 130 140 150 160 170 180 LTDPAKGMKG AVQKAEEIRD KTPNSYILQQ FENPANPKVH YETTGPEIWK GTGGKIDIFV 190 200 210 220 230 240 SGIGTGGTIT GAGKYLKEQN PDVKLIGLEP VESAVLSGGK PGPHKIQGLG AGFIPGVLDV 250 260 270 280 290 300 NIIDEVVQIS SEESIEMAKL LALKEGLLVG ISSGAAAAAA IKVAKRPENA GKLIVAVFPS 310 320 FGERYLSSVL FDSVRKEAES MVIES

References

[1]	"Molecular cloning and bacterial expression of cDNA encoding a plant cysteine synthase." Saito K., Miura N., Yamazaki M., Hirano H., Murakoshi I. Proc. Natl. Acad. Sci. U.S.A. 89:8078-8082(1992) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA], PROTEIN SEQUENCE OF 5-11; 71-90; 163-182 AND 246-262. Strain: cv. Parade. Tissue: Leaf.
[2]	"Determination of a functional lysine residue of a plant cysteine synthase by site-directed mutagenesis, and the molecular evolutionary implications." Saito K., Kurosawa M., Murakoshi I. FEBS Lett. 328:111-114(1993) [PubMed] [Europe PMC] [Abstract] Cited for: MUTAGENESIS OF LYSINE RESIDUES.

Cross-references

Sequence databases
EMBL GenBank DDBJ	D10476 mRNA. Translation: BAA01279.1.
PIR	S35094.
3D structure databases
ProteinModelPortal	Q00834.
SMR	Q00834. Positions 8-325.
ModBase	Search...
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Enzyme and pathway databases
UniPathway	UPA00136; UER00200.
Family and domain databases
InterPro	IPR001216. Cys_synth_BS. IPR005856. Cys_synthKM. IPR005859. CysK. IPR001926. Trp_syn_b_sub_like_PLP_eny_SF. [Graphical view]
Pfam	PF00291. PALP. 1 hit. [Graphical view]
SUPFAM	SSF53686. PyrdxlP-dep_enz_bsu. 1 hit.
TIGRFAMs	TIGR01139. cysK. 1 hit. TIGR01136. cysKM. 1 hit.
PROSITE	PS00901. CYS_SYNTHASE. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

CYSK_SPIOL

Accession

Primary (citable) accession number: Q00834

Entry history

Integrated into UniProtKB/Swiss-Prot:	April 1, 1993
Last sequence update:	April 1, 1993
Last modified:	April 3, 2013
This is version 78 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Plant Protein Annotation Program