ID   U77B2_CROXC             Reviewed;         456 AA.
AC   A0A2Z5CVA1;
DT   16-OCT-2019, integrated into UniProtKB/Swiss-Prot.
DT   10-OCT-2018, sequence version 1.
DT   03-AUG-2022, entry version 13.
DE   RecName: Full=Myricetin 3-O-rhamnosyltransferase UGT77B2 {ECO:0000305};
DE            EC=2.4.1.- {ECO:0000269|PubMed:29967287};
DE   AltName: Full=UDP-glucosyltransferase 1 {ECO:0000303|PubMed:31004005};
DE            Short=CcUGT1 {ECO:0000303|PubMed:31004005};
GN   Name=UGT77B2 {ECO:0000303|PubMed:29967287};
GN   Synonyms=UGT1 {ECO:0000303|PubMed:31004005};
OS   Crocosmia x crocosmiiflora (Montbretia) (Crocosmia aurea x Crocosmia
OS   pottsii).
OC   Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta;
OC   Spermatophyta; Magnoliopsida; Liliopsida; Asparagales; Iridaceae;
OC   Crocoideae; Freesieae; Crocosmia.
OX   NCBI_TaxID=1053288;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, CATALYTIC ACTIVITY, AND TISSUE
RP   SPECIFICITY.
RX   PubMed=29967287; DOI=10.1105/tpc.18.00406;
RA   Irmisch S., Jo S., Roach C.R., Jancsik S., Man Saint Yuen M., Madilao L.L.,
RA   O'Neil-Johnson M., Williams R., Withers S.G., Bohlmann J.;
RT   "Discovery of UDP-glycosyltransferases and BAHD-acyltransferases involved
RT   in the biosynthesis of the antidiabetic plant metabolite montbretin A.";
RL   Plant Cell 30:1864-1886(2018).
RN   [2]
RP   FUNCTION, AND CATALYTIC ACTIVITY.
RX   PubMed=31004005; DOI=10.1104/pp.19.00254;
RA   Irmisch S., Ruebsam H., Jancsik S., Man Saint Yuen M., Madilao L.L.,
RA   Bohlmann J.;
RT   "Flavonol biosynthesis genes and their use in engineering the plant
RT   antidiabetic metabolite montbretin A.";
RL   Plant Physiol. 180:1277-1290(2019).
CC   -!- FUNCTION: Rhamnosyltransferase involved in montbretin A (MbA)
CC       biosynthesis (PubMed:29967287, PubMed:31004005). Catalyzes the 3-O
CC       rhamnosylation of myricetin to produce myricetin 3-O-alpha-L-rhamnoside
CC       (MR), a precursor of MbA (PubMed:29967287, PubMed:31004005). MbA is a
CC       potent inhibitor of human pancreatic alpha-amylase and is being
CC       developed as drug candidate to treat type-2 diabetes (PubMed:29967287,
CC       PubMed:31004005). In vitro, is able to transfer UDP-glucose and UDP-
CC       xylose with 50-fold less efficiency compared with UDP-rhamnose
CC       (PubMed:29967287). In vitro, can use kaempferol or quercetin as
CC       substrates, although these two flavonols may not be physiological
CC       substrates in vivo (PubMed:29967287). {ECO:0000269|PubMed:29967287,
CC       ECO:0000269|PubMed:31004005}.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=myricetin + UDP-beta-L-rhamnose = H(+) + myricetin 3-O-alpha-
CC         L-rhamnoside + UDP; Xref=Rhea:RHEA:61144, ChEBI:CHEBI:15378,
CC         ChEBI:CHEBI:58223, ChEBI:CHEBI:58395, ChEBI:CHEBI:83836,
CC         ChEBI:CHEBI:144432; Evidence={ECO:0000269|PubMed:29967287,
CC         ECO:0000269|PubMed:31004005};
CC       PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:61145;
CC         Evidence={ECO:0000269|PubMed:29967287, ECO:0000269|PubMed:31004005};
CC   -!- PATHWAY: Flavonoid metabolism. {ECO:0000305}.
CC   -!- TISSUE SPECIFICITY: Expressed in young cromes.
CC       {ECO:0000269|PubMed:29967287}.
CC   -!- SIMILARITY: Belongs to the UDP-glycosyltransferase family.
CC       {ECO:0000305}.
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DR   EMBL; MG938542; AXB26715.1; -; mRNA.
DR   AlphaFoldDB; A0A2Z5CVA1; -.
DR   SMR; A0A2Z5CVA1; -.
DR   GO; GO:0008194; F:UDP-glycosyltransferase activity; IEA:InterPro.
DR   CDD; cd03784; GT1_Gtf-like; 1.
DR   InterPro; IPR002213; UDP_glucos_trans.
DR   InterPro; IPR035595; UDP_glycos_trans_CS.
DR   Pfam; PF00201; UDPGT; 1.
DR   PROSITE; PS00375; UDPGT; 1.
PE   1: Evidence at protein level;
KW   Glycosyltransferase; Transferase.
FT   CHAIN           1..456
FT                   /note="Myricetin 3-O-rhamnosyltransferase UGT77B2"
FT                   /id="PRO_0000448217"
FT   BINDING         19
FT                   /ligand="UDP-alpha-D-glucose"
FT                   /ligand_id="ChEBI:CHEBI:58885"
FT                   /evidence="ECO:0000250|UniProtKB:Q7XT97"
FT   BINDING         279
FT                   /ligand="UDP-alpha-D-glucose"
FT                   /ligand_id="ChEBI:CHEBI:58885"
FT                   /evidence="ECO:0000250|UniProtKB:Q7XT97"
FT   BINDING         351..359
FT                   /ligand="UDP-alpha-D-glucose"
FT                   /ligand_id="ChEBI:CHEBI:58885"
FT                   /evidence="ECO:0000250|UniProtKB:Q7XT97"
FT   BINDING         375..376
FT                   /ligand="UDP-alpha-D-glucose"
FT                   /ligand_id="ChEBI:CHEBI:58885"
FT                   /evidence="ECO:0000250|UniProtKB:Q7XT97"
SQ   SEQUENCE   456 AA;  48737 MW;  97BEDAD2E9C9B576 CRC64;
     MDSASRQHVA LIAFPFASHP GNLFAFARAL AAAAPDITFS FLTTTFAAAT LPPAPPAANL
     RLCHVADGVP EGGLPPGTTI HGRIGMFLRA TPGNFRDGVR AAEEEVGVKV SCVVSDAFLW
     MTADVAEEIG AQWLPLWTCA PAALLAHVST DQLRERFGVE KQATAGWADE LVDFIPGLSC
     LRIRDIPDEI VTNWHSDLSI LLHRMGNQLT SATAVALNTF DGLDTTIDAA LASLFKKTLP
     IGPLNLLSSP PPLQPGDEKC LSWLDGQEDA TVAYVSFGTM VLMPTQSDVS EIAQGLESSG
     VRFLWSLREE ARAGLLPPGF LERTAGRGLV VPWAPQVRVL GHRAVGAFVT HCGWNAVMES
     VTSGVPMACL PSFADQKTNA RMVSAAWGIG EALRGEKVTK EEVVRSMEIV MMGEEGRRMR
     ERIGNLREKA AEAVGPGGSS SENFKSVLEM VRGTAN