Reviewed, UniProtKB/Swiss-Prot Q9LTB2 (MMT1_ARATH)

Names and origin

Protein names

Recommended name:
    Methionine S-methyltransferase
    EC=2.1.1.12
Alternative name(s):
    AdoMet:Met S-methyltransferase

Gene names

Name:	MMT1
Synonyms:	MMT
Ordered Locus Names:	At5g49810
ORF Names:	K21G20.2

Organism

Arabidopsis thaliana (Mouse-ear cress) [Complete proteome]

Taxonomic identifier

3702 [NCBI]

Taxonomic lineage

Eukaryota › Viridiplantae › Streptophyta › Embryophyta › Tracheophyta › Spermatophyta › Magnoliophyta › eudicotyledons › core eudicotyledons › rosids › eurosids II › Brassicales › Brassicaceae › Arabidopsis

Protein attributes

Sequence length	1071 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is not processed.
Protein existence	Evidence at transcript level.

General annotation (Comments)

Function	Catalyzes the S-methylmethionine (SMM) biosynthesis from adenosyl-L-homocysteine (AdoMet) and methionine. SMM biosynthesis (by MMT1) and degradation (by HMT-1, HMT-2 and HMT-3) constitute the SMM cycle in plants, which is probably required to achieve short term control of AdoMet level. Also able to catalyze the selenium-methylmethionine (SeMM) from AdoMet and selenium-methionine (SeMet). May play a role in phoem sulfur transport; such function is however not essential. Ref.1 Ref.4 Ref.6
Catalytic activity	S-adenosyl-L-methionine + L-methionine = S-adenosyl-L-homocysteine + S-methyl-L-methionine. Ref.1
Subunit structure	Homotetramer By similarity.
Subcellular location	Cytoplasm By similarity.
Tissue specificity	Expressed in roots, rosette leaves and cauline leaves. Expressed at a lower level in developing seeds. Ref.5
Sequence similarities	Belongs to the methyltransferase superfamily.

Ontologies

Keywords
Cellular component	Cytoplasm
Ligand	S-adenosyl-L-methionine
Molecular function	Methyltransferase Transferase
Technical term	Complete proteome
Gene Ontology (GO)
Biological process	S-adenosylmethionine metabolic process Ref.6 Inferred from mutant phenotype. Source: TAIR biosynthetic process Inferred from electronic annotation. Source: InterPro
Cellular component	cytoplasm Inferred from electronic annotation. Source: UniProtKB-SubCell
Molecular function	methionine S-methyltransferase activity Inferred from electronic annotation. Source: EC pyridoxal phosphate binding Inferred from electronic annotation. Source: InterPro transferase activity, transferring nitrogenous groups Inferred from electronic annotation. Source: InterPro
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 1071	1071	Methionine S-methyltransferase		PRO_0000204460
Experimental info
	Sequence conflict	269	1	I → V in AAD49574. Ref.1
	Sequence conflict	813	1	K → R in AAD49574. Ref.1
	Sequence conflict	885	1	M → L in AAD49574. Ref.1
	Sequence conflict	889	1	L → F in AAD49574. Ref.1
	Sequence conflict	968	1	R → K in AAD49574. Ref.1

Sequences

	Sequence		Length	Mass (Da)
	Q9LTB2-1 [UniParc]. Last modified October 1, 2000. Version 1. Checksum: 788D12B83CB47958	FASTA	1,071	118,716
	10 20 30 40 50 60 MADLSSVDEF LNQCKQSGDA AYGALRSVLE RLEDPNTRSK ARIFLSDIYK RVGSSETSLQ 70 80 90 100 110 120 TYHFHIQDIY LDQYEGFQSR KKLTMMVIPS IFIPEDWSFT FYEGLNRHPD TIFKDKTVSE 130 140 150 160 170 180 LGCGNGWISI AIAAKWLPSK VYGLDINPRA VKISWINLYL NALDDNGEPV YDEEKKTLLD 190 200 210 220 230 240 RVEFYESDLL GYCRDNKIQL ERIVGCIPQI LNPNPEAMSK LITENASEEF LHSLSNYCAL 250 260 270 280 290 300 QGFVEDQFGL GLIARAVEEG ISVIKPAGIM IFNMGGRPGQ GVCRRLFERR GVRVTQMWQT 310 320 330 340 350 360 KILQAADTDI SALVEIERSS PHRFEFFMGL SGDQPICART AWAYGKAGGR ISHALSVYSC 370 380 390 400 410 420 QIRQPNLVKI IFDFLKNGFQ EISNSLDLSF EDETVADEKI PFLAYLASVL KNSSYFPFEP 430 440 450 460 470 480 PAGSKRFCSL IAGFMRTYHR IPINQDNIVV FPSRAVAIES AFRLFSPRLA IVDEHLTRQL 490 500 510 520 530 540 PRSWLTSLAI EDTSMDKSDD QITVIESPHQ SDLMIELIKK LKPQVVVTGM APFEVITSSS 550 560 570 580 590 600 FLHLLEVTKE IGCRLFLDIS DHFELSSLPA SNGVLKYLAE NQLPSHAAII CGLVKNKVYS 610 620 630 640 650 660 DLEVAFVITE VDAIAKALSK TVEVLEGHTA IISQYYYGCL FHELLAFQLA DRHAPAERES 670 680 690 700 710 720 EKAKSEEIIG FSSSAVSILK DAELSVTEID ETSLIHMDVD QSFLQIPQSV KAAIFESFVR 730 740 750 760 770 780 QNISEAEVDI NPSIKQFVWS NYGFPTKSST GFVYADGSLA LFNKLVICCA QEGGTLCLPA 790 800 810 820 830 840 GTNGNYVAAA KFLKANVVNI PTESSDGFKL TEKTLTKALE SVKKPWVCIS GPTVSPTGLV 850 860 870 880 890 900 YSNEEMDILL STCAKFGAKV IIDTSFSGLE YSATSWDLKN ALSKMDSSLS VSLLGCLSLN 910 920 930 940 950 960 LLSGAIKLGF LVLDQSLIDA FHTLPGLSKP HSTVKYAAKK MLALKEEKAS DFLDAVSETI 970 980 990 1000 1010 1020 KTLEGRSRRL KEVLQNSGWE VIQPSAGISM VAKPKAYLNK KVKLKAGDGQ EIVELTDSNM 1030 1040 1050 1060 1070 RDVFLSHTGV CLNSGSWTGI PGYCRFSFAL EDSEFDKAIE SIAQFKSVLA N

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"S-methylmethionine plays a major role in phloem sulfur transport and is synthesized by a novel type of methyltransferase." Bourgis F., Roje S., Nuccio M.L., Fisher D.B., Tarczynski M.C., Li C., Herschbach C., Rennenberg H., Pimenta M.J., Shen T.-L., Gage D.A., Hanson A.D. Plant Cell 11:1485-1498(1999) [PubMed: 10449582] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, ENZYME ACTIVITY. Strain: cv. Landsberg erecta.
[2]	"Structural analysis of Arabidopsis thaliana chromosome 5. XI." Kaneko T., Katoh T., Asamizu E., Sato S., Nakamura Y., Kotani H., Tabata S. Submitted (APR-1999) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: cv. Columbia.
[3]	"Empirical analysis of transcriptional activity in the Arabidopsis genome." Yamada K., Lim J., Dale J.M., Chen H., Shinn P., Palm C.J., Southwick A.M., Wu H.C., Kim C.J., Nguyen M., Pham P.K., Cheuk R.F., Karlin-Newmann G., Liu S.X., Lam B., Sakano H., Wu T., Yu G. , Miranda M., Quach H.L., Tripp M., Chang C.H., Lee J.M., Toriumi M.J., Chan M.M., Tang C.C., Onodera C.S., Deng J.M., Akiyama K., Ansari Y., Arakawa T., Banh J., Banno F., Bowser L., Brooks S.Y., Carninci P., Chao Q., Choy N., Enju A., Goldsmith A.D., Gurjal M., Hansen N.F., Hayashizaki Y., Johnson-Hopson C., Hsuan V.W., Iida K., Karnes M., Khan S., Koesema E., Ishida J., Jiang P.X., Jones T., Kawai J., Kamiya A., Meyers C., Nakajima M., Narusaka M., Seki M., Sakurai T., Satou M., Tamse R., Vaysberg M., Wallender E.K., Wong C., Yamamura Y., Yuan S., Shinozaki K., Davis R.W., Theologis A., Ecker J.R. Science 302:842-846(2003) [PubMed: 14593172] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA]. Strain: cv. Columbia.
[4]	"An essential role of s-adenosyl-L-methionine:L-methionine s-methyltransferase in selenium volatilization by plants. Methylation of selenomethionine to selenium-methyl-L-selenium-methionine, the precursor of volatile selenium." Tagmount A., Berken A., Terry N. Plant Physiol. 130:847-856(2002) [PubMed: 12376649] [Abstract] Cited for: FUNCTION.
[5]	"The S-methylmethionine cycle in angiosperms: ubiquity, antiquity and activity." Ranocha P., McNeil S.D., Ziemak M.J., Li C., Tarczynski M.C., Hanson A.D. Plant J. 25:575-584(2001) [PubMed: 11309147] [Abstract] Cited for: TISSUE SPECIFICITY.
[6]	"Insertional inactivation of the methionine s-methyltransferase gene eliminates the s-methylmethionine cycle and increases the methylation ratio." Kocsis M.G., Ranocha P., Gage D.A., Simon E.S., Rhodes D., Peel G.J., Mellema S., Saito K., Awazuhara M., Li C., Meeley R.B., Tarczynski M.C., Wagner C., Hanson A.D. Plant Physiol. 131:1808-1815(2003) [PubMed: 12692340] [Abstract] Cited for: PROBABLE FUNCTION OF SMM CYCLE.

Cross-references

Sequence databases
EMBLGenBankDDBJ	AF137380 mRNA. Translation: AAD49574.1. AB025612 Genomic DNA. Translation: BAA98148.1. AY094459 mRNA. Translation: AAM19829.1. BT002664 mRNA. Translation: AAO11580.1.
IPI	IPI00522742.
PIR	T52306.
RefSeq	NP_199792.1.
UniGene	At.25276
3D structure databases
ModBase	Search...
Proteomic databases
PRIDE	Q9LTB2.
Genome annotation databases
GeneID	835044.
GenomeReviews	Gene locus AT5G49810 in contig BA000015_GR.
KEGG	ath:AT5G49810.
NMPDR	fig|3702.1.peg.26828.
Organism-specific databases
GeneFarm	4078.
TAIR	At5g49810.
Phylogenomic databases
OMA	Q9LTB2. NGWISIA.
Enzyme and pathway databases
BRENDA	2.1.1.12. 302.
Gene expression databases
ArrayExpress	Q9LTB2.
GermOnline	AT5G49810. Arabidopsis thaliana.
Family and domain databases
InterPro	IPR004839. Aminotrans_I/II. IPR015421. PyrdxlP-dep_Trfase_major_sub1. IPR007848. Small_mtfrase. [Graphical view]
Gene3D	G3DSA:3.40.640.10. PyrdxlP-dep_Trfase_major_sub1. 1 hit.
Pfam	PF00155. Aminotran_1_2. 1 hit. PF05175. MTS. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

MMT1_ARATH

Accession

Primary (citable) accession number: Q9LTB2
Secondary accession number(s): Q9SWR2

Entry history

Integrated into UniProtKB/Swiss-Prot:	July 19, 2004
Last sequence update:	October 1, 2000
Last modified:	June 16, 2009
This is version 54 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

PPAP (Plant Proteome Annotation Project)