KGLT_PETHY
ID KGLT_PETHY Reviewed; 451 AA.
AC Q9SBQ8;
DT 13-NOV-2007, integrated into UniProtKB/Swiss-Prot.
DT 01-MAY-2000, sequence version 1.
DT 03-AUG-2022, entry version 66.
DE RecName: Full=Kaempferol 3-O-beta-D-galactosyltransferase;
DE Short=F3GalTase;
DE EC=2.4.1.234;
DE Flags: Precursor;
OS Petunia hybrida (Petunia).
OC Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta;
OC Spermatophyta; Magnoliopsida; eudicotyledons; Gunneridae; Pentapetalae;
OC asterids; lamiids; Solanales; Solanaceae; Petunioideae; Petunia.
OX NCBI_TaxID=4102;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA], PROTEIN SEQUENCE OF 44-52; 231-254 AND 264-283,
RP TISSUE SPECIFICITY, DEVELOPMENTAL STAGE, BIOPHYSICOCHEMICAL PROPERTIES, AND
RP SUBUNIT.
RC TISSUE=Pollen;
RX PubMed=10567367; DOI=10.1074/jbc.274.48.34011;
RA Miller K.D., Guyon V., Evans J.N.S., Shuttleworth W.A., Taylor L.P.;
RT "Purification, cloning, and heterologous expression of a catalytically
RT efficient flavonol 3-O-galactosyltransferase expressed in the male
RT gametophyte of Petunia hybrida.";
RL J. Biol. Chem. 274:34011-34019(1999).
CC -!- FUNCTION: Involved in the formation of flavonol glycosides required for
CC pollen germination. Shows a strict specificity for UDP-galactose and
CC flavonols as substrates. Acts on kaempferol, quercetin, galangin, iso-
CC rhamnetin, kaempferide, rhamnetin, morin, myricetin and fisetin.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=kaempferol + UDP-alpha-D-galactose = H(+) + kaempferol 3-O-
CC beta-D-galactoside + UDP; Xref=Rhea:RHEA:15709, ChEBI:CHEBI:15378,
CC ChEBI:CHEBI:58223, ChEBI:CHEBI:58573, ChEBI:CHEBI:66914,
CC ChEBI:CHEBI:76104; EC=2.4.1.234;
CC -!- BIOPHYSICOCHEMICAL PROPERTIES:
CC Kinetic parameters:
CC KM=1.1 uM for kaempferol {ECO:0000269|PubMed:10567367};
CC KM=0.96 uM for quercetin {ECO:0000269|PubMed:10567367};
CC KM=426 uM for UDP-galactose with kaempferol as cosubstrate
CC {ECO:0000269|PubMed:10567367};
CC KM=387 uM for UDP-galactose with quercetin as cosubstrate
CC {ECO:0000269|PubMed:10567367};
CC KM=8.47 uM for kaempferol 3-O-galactoside
CC {ECO:0000269|PubMed:10567367};
CC KM=2.65 uM for quercetin 3-O-galactoside
CC {ECO:0000269|PubMed:10567367};
CC KM=66 uM for UDP with kaempferol 3-O-beta-D-galactoside as
CC cosubstrate {ECO:0000269|PubMed:10567367};
CC KM=102 uM for UDP with quercetin 3-O-beta-D-galactoside as
CC cosubstrate {ECO:0000269|PubMed:10567367};
CC Vmax=75 umol/min/mg enzyme with kaempferol as substrate
CC {ECO:0000269|PubMed:10567367};
CC Vmax=73.4 umol/min/mg enzyme with quercetin as substrate
CC {ECO:0000269|PubMed:10567367};
CC Vmax=75.1 umol/min/mg enzyme with UDP-galactose as substrate and
CC kaempferol as cosubstrate {ECO:0000269|PubMed:10567367};
CC Vmax=70.5 umol/min/mg enzyme with UDP-galactose as substrate and
CC quercetin as cosubstrate {ECO:0000269|PubMed:10567367};
CC Vmax=73.5 umol/min/mg enzyme with kaempferol 3-O-beta-D-galactoside
CC as substrate {ECO:0000269|PubMed:10567367};
CC Vmax=101 umol/min/mg enzyme with quercetin 3-O-beta-D-galactoside as
CC substrate {ECO:0000269|PubMed:10567367};
CC Vmax=62.5 umol/min/mg enzyme with UDP as substrate and kaempferol 3-
CC O-beta-D-galactoside as cosubstrate {ECO:0000269|PubMed:10567367};
CC Vmax=110 umol/min/mg enzyme with UDP as substrate and quercetin 3-O-
CC beta-D-galactoside as cosubstrate {ECO:0000269|PubMed:10567367};
CC pH dependence:
CC Optimum pH is 7.5 in the forward direction and 6.0 in the reverse
CC direction. {ECO:0000269|PubMed:10567367};
CC Temperature dependence:
CC Optimum temperature is 50 degrees Celsius.
CC {ECO:0000269|PubMed:10567367};
CC -!- SUBUNIT: Monomer. {ECO:0000269|PubMed:10567367}.
CC -!- TISSUE SPECIFICITY: Restricted to the male gametophyte.
CC {ECO:0000269|PubMed:10567367}.
CC -!- DEVELOPMENTAL STAGE: Expressed throughout pollen development.
CC {ECO:0000269|PubMed:10567367}.
CC -!- SIMILARITY: Belongs to the UDP-glycosyltransferase family.
CC {ECO:0000305}.
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DR EMBL; AF165148; AAD55985.1; -; mRNA.
DR AlphaFoldDB; Q9SBQ8; -.
DR SMR; Q9SBQ8; -.
DR CAZy; GT1; Glycosyltransferase Family 1.
DR KEGG; ag:AAD55985; -.
DR BioCyc; MetaCyc:MON-17892; -.
DR BRENDA; 2.4.1.234; 4700.
DR SABIO-RK; Q9SBQ8; -.
DR GO; GO:0033834; F:kaempferol 3-O-galactosyltransferase activity; IEA:UniProtKB-EC.
DR GO; GO:0102479; F:quercetin 3-O-beta:-D-galactosyltransferase activity; IEA:UniProtKB-EC.
DR GO; GO:0008194; F:UDP-glycosyltransferase activity; IEA:InterPro.
DR CDD; cd03784; GT1_Gtf-like; 1.
DR InterPro; IPR002213; UDP_glucos_trans.
DR Pfam; PF00201; UDPGT; 1.
PE 1: Evidence at protein level;
KW Direct protein sequencing; Glycosyltransferase; Signal; Transferase.
FT SIGNAL 1..30
FT /evidence="ECO:0000255"
FT CHAIN 31..451
FT /note="Kaempferol 3-O-beta-D-galactosyltransferase"
FT /id="PRO_0000310731"
SQ SEQUENCE 451 AA; 48907 MW; 8772AD70A9A67507 CRC64;
MSNYHVAVLA FPFATHAGLL LGLVQRLANA LPNVTFTFFN TSKSNSSLFT TPHDNNIKPF
NISDGVPEGY VVGKGGIEAL IGLFFKSAKE NIQNAMAAAV EESGKKITCV MADAFMWFSG
EIAEELSVGW IPLWTSAAGS LSVHVYTDLI RENVEAQGIA GREDEILTFI PGFAELRLGS
LPSGVVSGDL ESPFSVMLHK MGKTIGKATA LPVNSFEELD PPIVEDLKSK FNNFLNVGPF
NLTTPPPSAN ITDEYGCIAW LDKQEPGSVA YIGFGTVATP PPNELKAMAE ALEESKTPFL
WSLKDLFKSF FPEGFLERTS EYGKIVSWAP QVQVLSHGSV GVFINHCGWN SVLESIAAGV
PVICRPFFGD HQLNAWMVEK VWKIGVKIEG GVFTKDGTML ALDLVLSKDK RNTELKQQIG
MYKELALNAV GPSGSSAENF KKLVDIITSC N
