Q96553 (METK3_CATRO) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
S-adenosylmethionine synthase 3
Short name=AdoMet synthase 3
EC=2.5.1.6

Alternative name(s):
Methionine adenosyltransferase 3
Short name=MAT 3

Gene names

Name:

SAMS3

Organism

Catharanthus roseus (Madagascar periwinkle) (Vinca rosea)

Taxonomic identifier

4058 [NCBI]

Taxonomic lineage

Eukaryota › Viridiplantae › Streptophyta › Embryophyta › Tracheophyta › Spermatophyta › Magnoliophyta › eudicotyledons › core eudicotyledons › asterids › lamiids › Gentianales › Apocynaceae › Rauvolfioideae › Vinceae › Catharanthus

Protein attributes

Sequence length	390 AA.
Sequence status	Complete.
Protein existence	Evidence at protein level

General annotation (Comments)

Function	Catalyzes the formation of S-adenosylmethionine from methionine and ATP. The overall synthetic reaction is composed of two sequential steps, AdoMet formation and the subsequent tripolyphosphate hydrolysis which occurs prior to release of AdoMet from the enzyme By similarity.
Catalytic activity	ATP + L-methionine + H2O = phosphate + diphosphate + S-adenosyl-L-methionine.
Cofactor	Binds 2 divalent ions per subunit. Manganese, magnesium or cobalt. Ref.1 Binds 1 potassium ion per subunit. Can be replaced by NH4. Ref.1
Enzyme regulation	Inhibited by products of SAMS reaction (SAM, Pi, PPi), substrate analogs (cycloleucine and ethionine), and alternative nucleotides (GTP, CTP and ADP). Strongly repressed by PPPi. Ref.1
Pathway	Amino-acid biosynthesis; S-adenosyl-L-methionine biosynthesis; S-adenosyl-L-methionine from L-methionine: step 1/1.
Subunit structure	Homotetramer By similarity.
Subcellular location	Cytoplasm By similarity.
Tissue specificity	Mostly expressed in roots, and, to a lower extent, in hypocotyls and cotyledons. Ref.1
Induction	Transiently induced by elicitors from Phytophthora megasperma, salt stress, and sucrose. Ref.1
Sequence similarities	Belongs to the AdoMet synthase family.
Biophysicochemical properties	Kinetic parameters: KM=102 µM for L-methionine Ref.1 KM=313 µM for ATP pH dependence: Optimum pH is 7-8.3. Temperature dependence: Optimum temperature is 37-45 degrees Celsius.

Ontologies

Keywords
Biological process	One-carbon metabolism
Cellular component	Cytoplasm
Ligand	ATP-binding Cobalt Magnesium Manganese Metal-binding Nucleotide-binding Potassium
Molecular function	Transferase
Gene Ontology (GO)
Biological process	S-adenosylmethionine biosynthetic process Inferred from electronic annotation. Source: InterPro one-carbon metabolic process Inferred from electronic annotation. Source: UniProtKB-KW
Cellular component	cytoplasm Inferred from electronic annotation. Source: UniProtKB-SubCell
Molecular function	ATP binding Inferred from electronic annotation. Source: UniProtKB-KW metal ion binding Inferred from electronic annotation. Source: UniProtKB-KW methionine adenosyltransferase 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 – 390	390	S-adenosylmethionine synthase 3		PRO_0000174461
Regions
	Nucleotide binding	119 – 124	6	ATP Potential
	Nucleotide binding	267 – 274	8	ATP Potential
Sites
	Metal binding	17	1	Magnesium By similarity
	Metal binding	43	1	Potassium By similarity
	Metal binding	271	1	Potassium By similarity
	Metal binding	279	1	Magnesium By similarity
	Binding site	147	1	ATP Potential

Sequences

	Sequence		Length	Mass (Da)
	Q96553 [UniParc]. Last modified February 1, 1997. Version 1. Checksum: 41E0ED8FA84DF776	FASTA	390	42,556
	10 20 30 40 50 60 METFLFTSES VNEGHPDKLC DQVSDAILDA CLEQDPESKV ACETCTKTNM VMVFGEITTK 70 80 90 100 110 120 ATVNYEKIVR DTCRGIGFTS PDVGLDADNC KVLVNIEQQS PDIAQGVHGH LTKKPEEIGA 130 140 150 160 170 180 GDQGHMFGYA TDETPELMPL THVLATKLGA KLTEVRKNKT CPWLRPDGKT QVTVEYRNEG 190 200 210 220 230 240 GAMVPIRVHT VLISTQHDET VTNEQIAQDL KEHVIKPVIP AQYLDDQTIF HLNPSGRFVI 250 260 270 280 290 300 GGPHGDAGLT GRKIIIDTYG GWGAHGGGAF SGKDPTKVDR SGAYIVRQAA KSVVASGLAR 310 320 330 340 350 360 RCLVQVSYAI GVAEPLSVFV DTFKTGKIPD KDILALIKEN FDFRPGMIAI NLDLKRGGNF 370 380 390 RYQKTAALGH LGRDDPDFTW ETVKILKPKA

References

[1]	"Three differentially expressed S-adenosylmethionine synthetases from Catharanthus roseus: molecular and functional characterization." Schroeder G., Eichel J., Breinig S., Schroeder J. Plant Mol. Biol. 33:211-222(1997) [PubMed: 9037140] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA], COFACTOR, BIOPHYSICOCHEMICAL PROPERTIES, ENZYME REGULATION, TISSUE SPECIFICITY, INDUCTION.
+	Additional computationally mapped references.

Cross-references

Sequence databases
EMBL GenBank DDBJ	Z71273 mRNA. Translation: CAA95858.1.
3D structure databases
ProteinModelPortal	Q96553.
SMR	Q96553. Positions 3-387.
ModBase	Search...
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Enzyme and pathway databases
BRENDA	2.5.1.6. 1211.
Family and domain databases
InterPro	IPR022631. ADOMET_SYNTHASE_CS. IPR022630. S-AdoMet_synt_C. IPR022629. S-AdoMet_synt_central. IPR022628. S-AdoMet_synt_N. IPR002133. S-AdoMet_synthetase. IPR022636. S-AdoMet_synthetase_sfam. [Graphical view]
PANTHER	PTHR11964. S-AdoMet_synt. 1 hit.
Pfam	PF02773. S-AdoMet_synt_C. 1 hit. PF02772. S-AdoMet_synt_M. 1 hit. PF00438. S-AdoMet_synt_N. 1 hit. [Graphical view]
PIRSF	PIRSF000497. MAT. 1 hit.
SUPFAM	SSF55973. S-AdoMet_synt. 3 hits.
TIGRFAMs	TIGR01034. MetK. 1 hit.
PROSITE	PS00376. ADOMET_SYNTHASE_1. 1 hit. PS00377. ADOMET_SYNTHASE_2. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

METK3_CATRO

Accession

Primary (citable) accession number: Q96553

Entry history

Integrated into UniProtKB/Swiss-Prot:	July 15, 1998
Last sequence update:	February 1, 1997
Last modified:	June 28, 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