Year: 2012
Type: article
Abstract: Several trypsin inhibitors named LHTIs (Liliaceae hyacinth trypsin inhibitors) have been isolated from hyacinth bulbs in our laboratory, and their properties and primary structures have been examined.LHTIs belong to the Bowman-Birk inhibitor family.cDNA cloning experiment has revealed that two similar LHTIs were encoded tandemly separated by a unique sequence (a linker sequence) unrelated to mature inhibitors.Two cDNA clones lhti-x1 and lhti-y1 were then expressed in Escherichia coli as fusion proteins with thioredoxin and several variants with mutated sequences at the reactive site or the neighboring residues were also prepared similarly.The protein LHTI-X1 obtained from lhti-x1 having a reactive site of Leu-Met inhibited trypsin and elastase as well as chymotrypsin.On the other hand, the protein LHTI-Y1 with a reactive site of Trp-Val showed no inhibitory activity to any proteases including chymotrypsin.However, an LHTI-X2 variant having Thr residue instead of Ser at the P 2 subsite inhibited chymotrypsin.The inhibitory mechanism of LHTI to serine proteases is also discussed.
Authors: 成之 寺田, 敦子 渡部, 佳孝 古田, 枝里奈 前川, 真由 上村, Shigeyuki Terada, Atsuko Watanabe, Yoshitaka Furuta, Erina Maekawa, Mayu Uemura
Language: Japanese
Subfield: Cancer Research
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W7257229