title: Fluorescent analogs of trypsin inhibitor SFTI-1 isolated from sunflower seeds--synthesis and applications.
abstract: This article describes the synthesis and enzymatic study of newly synthesized analogs of trypsin inhibitors SFTI-1 that were fluorescent labeled on their N-terminal amino groups. Two fluorescent derivatives of benzoxazole (3-[2-(4-diphenylaminophenyl)benzoxazol-5-yl]-L-alanine-[(4NPh2 )Ph]Box-Ala and 3-[2-(2',4',5'-trimethoxyphenyl)benzoxazol-5-yl]-L-alanine-[2,4,5-(OMe)3Ph]Box-Ala) were used as efficient fluorescent labels. The compounds obtained preserved their inhibitory activity and were efficient inhibitors of bovine trypsin or chymotrypsin. Nevertheless, their association inhibition constants were one or two orders of magnitude lower than those determined for unlabeled monocyclic SFTI-1 or [Phe(5)]SFTI-1, respectively. The conjugates obtained were found to be proteolytically stable in the presence of cognate enzymes. Applying such fluorescent peptides, we were able to investigate enzyme-inhibitor complex formation using fluorescent techniques. We found that such compounds were rapidly internalized by the fibroblast or cancer cells with no cytotoxic effects.
authors.affiliation: Faculty of Chemistry, Gdansk University, Wita Stwosza 63, 80-952, Gdansk, Poland.
authors.forename: Adam
authors.initials: A
authors.lastname: Lesner
authors.forename: Natalia
authors.initials: N
authors.lastname: Karna
authors.forename: Mateusz
authors.initials: M
authors.lastname: Psurski
authors.forename: Anna
authors.initials: A
authors.lastname: Lęgowska
authors.forename: Magdalena
authors.initials: M
authors.lastname: Wysocka
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Guzow
authors.forename: Adam
authors.initials: A
authors.lastname: Sieradzan
authors.forename: Marcin
authors.initials: M
authors.lastname: Sieńczyk
authors.forename: Piotr
authors.initials: P
authors.lastname: Trzonkowski
authors.forename: Michał
authors.initials: M
authors.lastname: Pikuła
authors.forename: Maciej
authors.initials: M
authors.lastname: Zieliński
authors.forename: Paulina
authors.initials: P
authors.lastname: Kosikowska
authors.forename: Rałał
authors.initials: R
authors.lastname: Łukajtis
authors.forename: Monika
authors.initials: M
authors.lastname: Łęgowska
authors.forename: Dawid
authors.initials: D
authors.lastname: Dębowski
authors.forename: Wiesław
authors.initials: W
authors.lastname: Wiczk
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Rolka
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001583:Benzoxazoles / Q000737:chemistry; D002417:Cattle; D002460:Cell Line; D002463:Cell Membrane Permeability; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D005434:Flow Cytometry; D005453:Fluorescence; D006368:Helianthus / Q000737:chemistry*; D006801:Humans; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D010456:Peptides, Cyclic / Q000138:chemical synthesis* / Q000737:chemistry / Q000302:isolation & purification*; D012639:Seeds / Q000737:chemistry*; D013997:Time Factors; D014361:Trypsin Inhibitors / Q000138:chemical synthesis* / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D001583:Benzoxazoles; D010456:Peptides, Cyclic; C448501:SFTI-1 peptide, sunflower; D014361:Trypsin Inhibitors
keywords: SFTI-1; fluorescence; proteinase inhibitors