ID HMT1_BRAOT Reviewed; 326 AA.
AC A4ZGQ8;
DT 31-MAY-2011, integrated into UniProtKB/Swiss-Prot.
DT 29-MAY-2007, sequence version 1.
DT 06-MAR-2013, entry version 16.
DE RecName: Full=Homocysteine S-methyltransferase 1;
DE Short=BoHMT1;
DE EC=2.1.1.10;
GN Name=HMT1;
OS Brassica oleracea var. italica (Broccoli).
OC Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta;
OC Spermatophyta; Magnoliophyta; eudicotyledons; core eudicotyledons;
OC rosids; malvids; Brassicales; Brassicaceae; Brassiceae; Brassica.
OX NCBI_TaxID=36774;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, CATALYTIC ACTIVITY,
RP BIOPHYSICOCHEMICAL PROPERTIES, ENZYME REGULATION, TISSUE SPECIFICITY,
RP AND INDUCTION BY SELENATE.
RC STRAIN=cv. Green comet;
RX PubMed=17391716; DOI=10.1016/j.phytochem.2007.02.007;
RA Lyi S.M., Zhou X., Kochian L.V., Li L.;
RT "Biochemical and molecular characterization of the homocysteine S-
RT methyltransferase from broccoli (Brassica oleracea var. italica).";
RL Phytochemistry 68:1112-1119(2007).
CC -!- FUNCTION: Catalyzes methyl transfer from S-methylmethionine to
CC homocysteine. The highest preference is for DL-homocysteine >> DL-
CC cysteine. Has no selenocysteine methyltransferase activity.
CC -!- CATALYTIC ACTIVITY: S-methyl-L-methionine + L-homocysteine = 2 L-
CC methionine.
CC -!- COFACTOR: Zinc (Potential).
CC -!- ENZYME REGULATION: Inhibited by L-methionine.
CC -!- BIOPHYSICOCHEMICAL PROPERTIES:
CC Kinetic parameters:
CC KM=72 uM for DL-homocysteine;
CC pH dependence:
CC Optimum pH is 7.2;
CC -!- TISSUE SPECIFICITY: Expressed in roots, young leaves, florets and
CC flowers. Not detected in old leaves.
CC -!- INDUCTION: Not induced by selenate or selenite. Up-regulated by
CC sulfate. Not affected by the status of methionine, s-
CC methylmethionine or homocysteine, or by cadmium.
CC -!- SIMILARITY: Contains 1 Hcy-binding domain.
CC -----------------------------------------------------------------------
CC Copyrighted by the UniProt Consortium, see http://www.uniprot.org/terms
CC Distributed under the Creative Commons Attribution-NoDerivs License
CC -----------------------------------------------------------------------
DR EMBL; DQ679980; ABG74913.1; -; mRNA.
DR BioCyc; MetaCyc:MONOMER-15250; -.
DR BRENDA; 2.1.1.10; 947.
DR GO; GO:0008898; F:homocysteine S-methyltransferase activity; IDA:UniProtKB.
DR GO; GO:0046872; F:metal ion binding; IEA:UniProtKB-KW.
DR Gene3D; 3.20.20.330; -; 1.
DR InterPro; IPR003726; S_MeTrfase.
DR Pfam; PF02574; S-methyl_trans; 1.
DR SUPFAM; SSF82282; S_methyl_trans; 1.
DR PROSITE; PS50970; HCY; 1.
PE 1: Evidence at protein level;
KW Metal-binding; Methyltransferase; Transferase; Zinc.
FT CHAIN 1 326 Homocysteine S-methyltransferase 1.
FT /FTId=PRO_0000409376.
FT DOMAIN 9 323 Hcy-binding.
FT METAL 241 241 Zinc (Potential).
FT METAL 308 308 Zinc (Potential).
FT METAL 309 309 Zinc (Potential).
SQ SEQUENCE 326 AA; 35817 MW; E7B32300AE2FB4A2 CRC64;
MGLEKKSALL EDLIEKCGGC AVVDGGFATQ LEIHGAAIND PLWSAVSLIK DPELIKRVHM
EYLEAGADVV VTSSYQATIP GFLSRGLSME ESESLLQKSV KLAVEARDRF WDKVSKTSGH
SYNRALVAAS IGSYGAYLAD GSEYSGSYGE DVSLDKLKDF HRRRIQVLVE ASPDLLAFET
IPNKLEAQAC VELLEEENVQ IPAWICFTSV DGENAPSGES FQECLETLNK SNNICAVGIN
CAPPQFMDNL IRKFSKLTQK AIVVYPNSGE VWDGKAKKWL PSQCFGDAEF EMFATKWRDL
GAKLIGGCCR TTPSTIKAIS RDLKRR
//
