Preliminary analysis of the proteolytic enzymes in the excretory-secretory products of the adult stages of the dog hookworm Uncinaria stenocephala.

The paper describes an introductory characterisation of proteinases present in the excretory-secretory products (ESP) of adult Uncinaria stenocephala. In SDS-PAGE gelatine substrate gels ESP resolved as a six bands of proteolytic activity, with a molecular weight of 182, 159, 98, 50, 39 and 26 kDa. The 98 and 39 kDa components were serine proteinases. The 50 kDa band was sensitive to a metalloproteinase inhibitor. The 26 kDa component was highly sensitive to cysteine proteinase inhibitors and was also partially inhibited in the presence of EDTA. The bands of 182 and 159 kDa were sensitive to a Zn-metalloproteinase inhibitor. The enzymes present in ESP showed the highest proteolytic activity at pH 8-9. Quantitative analysis revealed maximum proteolytic activity of the polypeptides of 159 and 182 kDa at pH 7; 98 and 26 kDa at pH 8 while the 50 kDa and 39 kDa components showed the highest activity at pH 9.