Structure and properties of the potato chymotrypsin inhibitor.

The potato tubers contain proteins that inhibit serine proteinases and belong to subfamily of potato Kunitz-type proteinase inhibitors (PKPI). New highly purified protein had been isolated from mature potato tubers (Solanum tuberosum L., cv.

Comparative analyses of exoproteinases produced by three phytopathogenic microorganisms.

Proteinases secreted by the oomycete Phytophthora infestans (Mont.) de Bary, Rhizoctonia solani, and Fusarium culmorum belonging to different families of fungi have been studied to determine if the exoenzyme secretion depends on the environmental conditions and the phylogenetic position of the pathogen. The substrate specificity of the extracellular proteinases of F.

Kunitz-type protease inhibitors group B from Solanum palustre.

Five Kunitz protease inhibitor group B genes were isolated from the genome of the diploid non-tuber-forming potato species Solanum palustre. Three of five new genes share 99% identity to the published KPI-B genes from various cultivated potato accessions, while others exhibit 96% identity. Spls-KPI-B2 and Spls-KPI-B4 proteins contain unique substitutions of the most conserved residues usually involved to trypsin and chymotrypsin-specific binding sites of Kunitz-type protease inhibitor (KPI)-B, respectively.