Abstract
An acid proteinase of Dirofilaria immitis worms was purified 437-fold by gel filteration on Sephadex G-75 followed by pepstatin-agarose gel affinity chromatography. The enzyme with a molecular weight of 42 000 and specific activity of 384 units (mg protein) −1 was homogeneous as judged by both affinity chromatography and SDS-polyacrylamide gel electrophoresis. However, polyacrylamide disc electrophoresis at pH 8.9 revealed that the enzyme is composed of 5 multiforms, all carrying proteinase activity. Optimum pH of the enzyme was in the range of pH 2.8-3.4, and its isoelectric point ranged between 5.8 and 6.4. The purified proteinase showed a potent activity against hemoglobin and myglobin releasing acid soluble peptides, but not free amino acids. Complete inhibition of the proteolytic activity by pepstatin in the order of 10 −7M strongly suggests that the enzyme belongs to the carboxyl-proteinase family.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
