A brief report on some health aspects of rats fed with crescent levels of recombinant chagasin, a potential plant defense protein.

Chagasin may be considered a potential plant-incorporated protectant (PIP) protein due to its deleterious effects on insect pests. However, extensive safety studies with PIP's are necessary before introducing them into the target plant. Thus, a short-term feeding trial in rats with high doses of r-chagasin was conducted to provide evidences about its safety.

Molecular modeling and inhibitory activity of cowpea cystatin against bean bruchid pests.

Plant cystatins show great potential as tools to genetically engineer resistance of crop plants against pests. Two important potential targets are the bean weevils Acanthoscelides obtectus and Zabrotes subfasciatus, which display major activities of digestive cysteine proteinases in midguts. In this study a cowpea cystatin, a cysteine proteinase inhibitor found in cowpea (Vigna unguiculata) seeds, was expressed in Escherichia coli and purified with a Ni-NTA agarose column.

Pro domain peptide of HGCP-Iv cysteine proteinase inhibits nematode cysteine proteinases.

Cysteine proteinases (CPs) are synthesized as zymogens and converted to mature proteinase forms by proteolytic cleavage and release of their pro domain peptides. A cDNA encoding a papain-like CP, called hgcp-Iv, was isolated from a Heterodera glycines J2 cDNA library, expressed and utilized to assess the ability of its propeptide to inhibit proteinase in its active form. The hgcp-Iv cDNA sequence encodes a polypeptide of 374 amino acids with the same domain organization as other cathepsin L-like CPs, including a hydrophobic signal sequence and a pro domain region.

Molecular cloning of a cysteine proteinase cDNA from the cotton boll weevil Anthonomus grandis (Coleoptera: Curculionidae).

The cotton boll weevil (Anthonomus grandis) causes severe cotton crop losses in North and South America. This report describes the presence of cysteine proteinase activity in the cotton boll weevil. Cysteine proteinase inhibitors from different sources were assayed against total A.

Effects of soybean Kunitz trypsin inhibitor on the cotton boll weevil (Anthonomus grandis).

The cotton boll weevil, Anthonomus grandis, is an economically important pest of cotton in tropical and subtropical areas of several countries in the Americas, causing severe losses due to their damage in cotton floral buds. Enzymatic assays using gut extracts from larval and adult boll weevil have demonstrated the presence of digestive serine proteinase-like activities. Furthermore, in vitro assays showed that soybean Kunitz trypsin inhibitor (SKTI) was able to inhibit these enzymes.