ID IBBB4_HYAOR Reviewed; 57 AA. AC C0HLT0; DT 02-JUN-2021, integrated into UniProtKB/Swiss-Prot. DT 02-JUN-2021, sequence version 1. DT 22-FEB-2023, entry version 6. DE RecName: Full=Bowman-Birk type proteinase inhibitor B4 {ECO:0000303|PubMed:33666645}; DE Short=HOSPI-B4 {ECO:0000303|PubMed:33666645}; OS Hyacinthus orientalis (Common hyacinth). OC Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta; OC Spermatophyta; Magnoliopsida; Liliopsida; Asparagales; Hyacinthaceae; OC Hyacinthoideae; Hyacintheae; Hyacinthus. OX NCBI_TaxID=82025; RN [1] RP PROTEIN SEQUENCE, FUNCTION, AND TISSUE SPECIFICITY. RC TISSUE=Bulb {ECO:0000303|PubMed:33666645}; RX PubMed=33666645; DOI=10.1042/bcj20201005; RA Aoki-Shioi N., Terada S., Hellinger R., Furuta Y., Gruber C.W.; RT "Isolation and functional diversity of Bowman-Birk type serine proteinase RT inhibitors from Hyacinthus orientalis."; RL Biochem. J. 478:1287-1301(2021). CC -!- FUNCTION: Serine protease inhibitor (PubMed:33666645). Inhibits trypsin CC (Ki = 110 nM) and very weakly inhibits chymotrypsin (Ki =1200 nM) CC (PubMed:33666645). Does not inhibit bacterial subtilisin CC (PubMed:33666645). {ECO:0000269|PubMed:33666645}. CC -!- TISSUE SPECIFICITY: Expressed in bulb (at protein level). CC {ECO:0000269|PubMed:33666645}. CC -!- SIMILARITY: Belongs to the Bowman-Birk serine protease inhibitor CC family. {ECO:0000305}. CC --------------------------------------------------------------------------- CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms CC Distributed under the Creative Commons Attribution (CC BY 4.0) License CC --------------------------------------------------------------------------- DR AlphaFoldDB; C0HLT0; -. DR SMR; C0HLT0; -. DR GO; GO:0005576; C:extracellular region; IEA:InterPro. DR GO; GO:0004867; F:serine-type endopeptidase inhibitor activity; IDA:UniProtKB. DR GO; GO:0010951; P:negative regulation of endopeptidase activity; IDA:UniProtKB. DR Gene3D; 2.10.69.10; Cysteine Protease (Bromelain) Inhibitor, subunit H; 1. DR InterPro; IPR035995; Bowman-Birk_prot_inh. PE 1: Evidence at protein level; KW Direct protein sequencing; Disulfide bond; Protease inhibitor; KW Serine protease inhibitor. FT CHAIN 1..57 FT /note="Bowman-Birk type proteinase inhibitor B4" FT /id="PRO_0000452980" FT SITE 14..15 FT /note="Reactive bond for trypsin" FT /evidence="ECO:0000250|UniProtKB:P80321" FT DISULFID 6..55 FT /evidence="ECO:0000250|UniProtKB:P80321" FT DISULFID 12..17 FT /evidence="ECO:0000250|UniProtKB:P80321" FT DISULFID 26..33 FT /evidence="ECO:0000250|UniProtKB:P80321" FT DISULFID 30..47 FT /evidence="ECO:0000250|UniProtKB:P80321" SQ SEQUENCE 57 AA; 6321 MW; A3290C0D26E6D107 CRC64; GQQPLCNDCF ACARSLCICG DLVPQCHEGC QQCEKVDTLS GKPLYQCRSF EDYQCAN //