PPepDB-ID	"Peptide Name"	PMID	"Plant source"	"Plant Family"	"Peptide Family"	"Peptide function"	"Peptide function description"	"Activity against"	Sequence	"Sequence Length"	Validation	"Avg. Molecular wt(Da)"	"Monoisotopic molecular wt(Da)"	pI	Method	"Additional information"
PPepDB_5642	SPI1_SOLTU	--NA--	"Solanum tuberosum"	Solanaceae	--NA--	Signaling-peptide	"Direct protein sequencing; Protease inhibitor; Serine protease inhibitor; Signal; Vacuole | Serine protease inhibitor 1 precursor (PSPI-21) (PSPI-21-6.3),[Contains: Serine protease inhibitor 1 chain A; Serine protease,inhibitor 1 chain B].Vacuole (By similarity)."	--NA--	GKRRLALVKDNPLDISFKQVQIGQADSSWFKIVKSSQLGYNLLYCPVTSTMSCPFSSDDQFCLKVGVVHQNMKCLFLVCLCLVPIVVFSSTFTSQNPINLPSDATPVLDVTGKELDSRLSYRIISTFWGALGGDVYLGKSPNSDAPCANGVFRYNSDVGPSGTPVRFIGSSSHFGQGIFENELLNIQFAISTSKLCVSYTIWKVGDYDASLGTMLLETGGT	221	"Experimental evidence at protein level"	24009.5	23994.03	6.87	--NA--	"FUNCTION:Potent inhibitor of serine proteases (chymotrypsin and trypsin). Inhibits tightly human leukocyte elastase (HLE). Does not inhibit papain, pepsin nor cathepsin D (cysteine and aspartic proteases). Protects the plant by inhibiting proteases of invading organisms, decreasing both hyphal growth and zoospores germination of Phytophthora infestans.SUBUNIT:Heterodimer of chains A and B; disulfide-linked. Double- headed inhibitor able to form triple complexes with target proteases, by binding simultaneously one molecule of trypsin and one molecule of chymotrypsin.TISSUE SPECIFICITY:Tubers.INDUCTION:By infection with Phytophthora infestans.PTM:Synthesized as a single-chain precursor which is cleaved to form chain A and chain B.MASS SPECTROMETRY:Mass=20262; Mass_error=20; Method=Electrospray; Range=29-178, 185-221; Note=The measured mass is that of the native protein composed of the 2 chains A and B; Source=PubMed:11209756;MASS SPECTROMETRY:Mass=16078; Mass_error=16; Method=Electrospray; Range=29-178; Source=PubMed:11209756;MASS SPECTROMETRY:Mass=4282; Mass_error=4; Method=Electrospray; Range=185-221; Source=PubMed:11209756;MISCELLANEOUS:The serine protease inhibitor PSPI-21 comprises two protein species with pI 5.2 and 6.3, denoted as PSPI-21-5.2 and PSPI-21-6.3. They may be encoded by two alleles at the same gene locus.SIMILARITY:Belongs to the protease inhibitor I3 (leguminous Kunitz-type inhibitor) family."