title: Kunitz-type serine protease inhibitor from potato (Solanum tuberosum L. cv. Jopung).
abstract: An antifungal protein, AFP-J, was purified from tubers of the potato (Solanum tuberosum cv. L Jopung) by various chromatographic columns. AFP-J strongly inhibited yeast fungal strains, including Candida albicans, Trichosporon beigelii, and Saccharomyces cerevisiae, whereas it exhibited no activity against crop fungal pathogens. Automated Edman degradation determined the partial N-terminal sequence of AFP-J to be NH2-Leu-Pro-Ser-Asp-Ala-Thr-Leu-Val-Leu-Asp-Gln-Thr-Gly-Lys-G lu-Leu-Asp-Ala-Arg-Leu-. The partially sequence had 83% homology with a serine protease inhibitor belonging to the Kunitz family, and the protein inhibited chymotrypsin, pepsin, and trypsin. Mass spectrometry showed that its molecular mass was 13 500.5 Da. This protease inhibitor suppressed over 50% the proteolytic activity at 400 microg/mL. These results suggest that AFP-J is an excellent candidate as a lead compound for the development of novel antiinfective agents.
authors.affiliation: Research Center for Proteineous Materials, Department of Genetic Engineering, Chosun University, 375 Seosuk-Dong, Korea.
authors.forename: Yoonkyung
authors.initials: Y
authors.lastname: Park
authors.forename: Bo Hwa
authors.initials: BH
authors.lastname: Choi
authors.forename: Ji-Sun
authors.initials: JS
authors.lastname: Kwak
authors.forename: Chang-Won
authors.initials: CW
authors.lastname: Kang
authors.forename: Hak-Tae
authors.initials: HT
authors.lastname: Lim
authors.forename: Hyeon-Sook
authors.initials: HS
authors.lastname: Cheong
authors.forename: Kyung-Soo
authors.initials: KS
authors.lastname: Hahm
mesh_terms: D000595:Amino Acid Sequence; D000935:Antifungal Agents / Q000494:pharmacology; D005658:Fungi / Q000187:drug effects; D006801:Humans; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D010940:Plant Proteins / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D035281:Plant Tubers / Q000737:chemistry*; D010944:Plants / Q000382:microbiology; D032322:Solanum / Q000737:chemistry*
chemical_list: D000935:Antifungal Agents; C053865:Kunitz-type protease inhibitor, plant; D010455:Peptides; D010940:Plant Proteins