Kunitz-type serine protease inhibitor from potato (Solanum tuberosum L. cv. Jopung).
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.
Park
Yoonkyung
Y
Research Center for Proteineous Materials, Department of Genetic Engineering, Chosun University, 375 Seosuk-Dong, Korea.
Choi
Bo Hwa
BH
Kwak
Ji-Sun
JS
Kang
Chang-Won
CW
Lim
Hak-Tae
HT
Cheong
Hyeon-Sook
HS
Hahm
Kyung-Soo
KS
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*
D000935:Antifungal Agents; C053865:Kunitz-type protease inhibitor, plant; D010455:Peptides; D010940:Plant Proteins