ID   CFI3_LOTJA              Reviewed;         225 AA.
AC   Q8H0F6;
DT   11-SEP-2007, integrated into UniProtKB/Swiss-Prot.
DT   01-MAR-2003, sequence version 1.
DT   03-AUG-2022, entry version 67.
DE   RecName: Full=Chalcone--flavanone isomerase 3;
DE            Short=Chalcone isomerase 3;
DE            EC=5.5.1.6;
GN   Name=CHI3;
OS   Lotus japonicus (Lotus corniculatus var. japonicus).
OC   Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta;
OC   Spermatophyta; Magnoliopsida; eudicotyledons; Gunneridae; Pentapetalae;
OC   rosids; fabids; Fabales; Fabaceae; Papilionoideae; 50 kb inversion clade;
OC   NPAAA clade; Hologalegina; robinioid clade; Loteae; Lotus.
OX   NCBI_TaxID=34305;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA], AND FUNCTION.
RC   STRAIN=cv. Gifu / B-129; TISSUE=Root;
RX   PubMed=12644647; DOI=10.1104/pp.004820;
RA   Shimada N., Aoki T., Sato S., Nakamura Y., Tabata S., Ayabe S.;
RT   "A cluster of genes encodes the two types of chalcone isomerase involved in
RT   the biosynthesis of general flavonoids and legume-specific 5-
RT   deoxy(iso)flavonoids in Lotus japonicus.";
RL   Plant Physiol. 131:941-951(2003).
CC   -!- FUNCTION: Catalyzes the intramolecular cyclization of bicyclic
CC       chalcones into tricyclic (S)-flavanones. Responsible for the
CC       isomerization of 4,2',4',6'-tetrahydroxychalcone (also termed chalcone)
CC       into naringenin. {ECO:0000269|PubMed:12644647}.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=a chalcone = a flavanone.; EC=5.5.1.6;
CC   -!- PATHWAY: Secondary metabolite biosynthesis; flavonoid biosynthesis.
CC   -!- MISCELLANEOUS: Part of the biosynthetic pathway for all classes of
CC       flavonoids, a large class of secondary plant metabolites, many of which
CC       are brightly colored.
CC   -!- SIMILARITY: Belongs to the chalcone isomerase family. {ECO:0000305}.
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DR   EMBL; AB073787; BAC54038.1; -; mRNA.
DR   AlphaFoldDB; Q8H0F6; -.
DR   SMR; Q8H0F6; -.
DR   ProMEX; Q8H0F6; -.
DR   OMA; NCVAHLK; -.
DR   BioCyc; MetaCyc:MON-4762; -.
DR   UniPathway; UPA00154; -.
DR   GO; GO:0045430; F:chalcone isomerase activity; IEA:UniProtKB-EC.
DR   GO; GO:0009813; P:flavonoid biosynthetic process; IEA:UniProtKB-UniPathway.
DR   Gene3D; 1.10.890.20; -; 1.
DR   Gene3D; 3.50.70.10; -; 1.
DR   InterPro; IPR044164; CFI.
DR   InterPro; IPR016087; Chalcone_isomerase.
DR   InterPro; IPR016088; Chalcone_isomerase_3-sand.
DR   InterPro; IPR016089; Chalcone_isomerase_bundle_sf.
DR   InterPro; IPR036298; Chalcone_isomerase_sf.
DR   PANTHER; PTHR28039; PTHR28039; 1.
DR   Pfam; PF02431; Chalcone; 1.
DR   SUPFAM; SSF54626; SSF54626; 1.
PE   2: Evidence at transcript level;
KW   Flavonoid biosynthesis; Isomerase.
FT   CHAIN           1..225
FT                   /note="Chalcone--flavanone isomerase 3"
FT                   /id="PRO_0000300844"
FT   BINDING         51
FT                   /ligand="substrate"
FT                   /evidence="ECO:0000250"
FT   BINDING         116
FT                   /ligand="substrate"
FT                   /evidence="ECO:0000250"
FT   BINDING         193
FT                   /ligand="substrate"
FT                   /evidence="ECO:0000250"
FT   SITE            109
FT                   /note="Important for catalytic activity"
FT                   /evidence="ECO:0000250"
SQ   SEQUENCE   225 AA;  24288 MW;  39A10E77B15DC6C6 CRC64;
     MAPVKGPLTP IQVENLQFPA SITSPATAKS YFLGGAGERG LTIEGKFIKF TGLGVYLEDK
     TVDSLATKWK GKSSQELLDS LDFYRDIISS PSEKLIRGSK LRPLSGVEYS RKVMENCVAH
     MKSTGTYGEA EAAAIGKFAE AFRNLDFPPG SSVFYRQSPD GELGLSFSPD DTLPEKEAVV
     IENKALSEAV LETMIGEHAV SPDLKRCLAE RLPAVLNQGL LLSGN