title: Identification of peptides in wheat germ hydrolysate that demonstrate calmodulin-dependent protein kinase II inhibitory activity.
abstract: Hydrolysis of wheat germ by proteases resulted in bioactive peptides that demonstrated an inhibitory effect against the vasoconstrictive Ca(2+)-calmodulin (CaM)-dependent protein kinase II (CaMK II). The hydrolysate by thermolysin (1.0wt%, 5h) showed a particularly potent CaMK II inhibition. As a result of mixed mode high-performance liquid chromatography of thermolysin hydrolysate with pH elution gradient ranging between 4.8 and 8.9, the fraction eluted at pH 8.9 was the most potent CaMK II inhibitor. From this fraction, Trp-Val and Trp-Ile were identified as CaMK II inhibitors. In Sprague-Dawley rats, an enhanced aortic CaMK II activity by 1μM phenylephrine was significantly (p<0.05) suppressed by 15-min incubation with 300μM Trp-Val or Trp-Ile. On the basis of Ca(2+)-chelating fluorescence and CaMK II activity assays, it was concluded that Trp-Val and Trp-Ile competed with Ca(2+)-CaM complex to bind to CaMK II with Ki values of 5.4 and 3.6μM, respectively.
authors.affiliation: Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School of Kyushu University, 6-10-1 Hakozaki, Fukuoka 812-8581, Japan.
authors.forename: Thanutchaporn
authors.initials: T
authors.lastname: Kumrungsee
authors.affiliation: Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School of Kyushu University, 6-10-1 Hakozaki, Fukuoka 812-8581, Japan.
authors.forename: Sayaka
authors.initials: S
authors.lastname: Akiyama
authors.affiliation: Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School of Kyushu University, 6-10-1 Hakozaki, Fukuoka 812-8581, Japan.
authors.forename: Jian
authors.initials: J
authors.lastname: Guo
authors.affiliation: Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School of Kyushu University, 6-10-1 Hakozaki, Fukuoka 812-8581, Japan.
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Tanaka
authors.affiliation: Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School of Kyushu University, 6-10-1 Hakozaki, Fukuoka 812-8581, Japan. Electronic address: tmatsui@agr.kyushu-u.ac.jp.
authors.forename: Toshiro
authors.initials: T
authors.lastname: Matsui
mesh_terms: D000818:Animals; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2 / Q000378:metabolism*; D008297:Male; D010455:Peptides; D010766:Phosphorylation; D051381:Rats; D017207:Rats, Sprague-Dawley; D013820:Thermolysin / Q000378:metabolism*; D014908:Triticum / Q000382:microbiology*
chemical_list: D010455:Peptides; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D013820:Thermolysin
keywords: Calmodulin-dependent protein kinase II; Peptides; Thermolysin; Wheat germ