Biomedical Research

All submissions of the EM system will be redirected to Online Manuscript Submission System. Authors are requested to submit articles directly to Online Manuscript Submission System of respective journal.

- Biomedical Research (2011) Volume 22, Issue 1

Mycobacterial secretory SEVA TB ES-31 antigen, a chymotrypsin-like serine protease with lipase activity and drug target potential

Mycobacterium tuberculosis is known to secrete number of proteins which play an important role in pathogenicity and diagnosis. A diagnostically important secreted antigen, Excretory Secretory-31 (SEVA TB ES-31) protein with serine protease activity was isolated from Mycobacterium tuberculosis H37Ra culture filtrate. Serine proteases like Chymotrypsin have been reported to possess lipase activ-ity as the catalytic triad is similar in serine protease and some lipase enzymes. In this study, ES-31 showed presence of 44.5U/mg pr of lipase activity by titrimetric assay. The lipase activity was inhib-ited by lipase inhibitor, Orlistat by 100%, as well as by serine metalloprotease inhibitors, Phenyl me-thyl sulphonyl fluoride and Ethylene Diamine Tetraacetic acid by 100%. The serine protease activity of ES-31 was inhibited by Phenyl methyl sulphonyl fluoride, Ethylene Diamine Tetraacetic acid, and orlistat by 78.3%, 64.3%, 89.4% respectively. Inhibition of serine protease activity of ES-31 by lipase inhibitor and inhibition of lipase activity of ES-31 by serine protease inhibitor suggests that the cata-lytic site of ES-31 is sensitive to both types of the inhibitors and ES-31 may be a chymotrypsin-like protein with drug target potential

Author(s): Gauri Wankhade, Anindita Majumdar, Pranita D Kamble, BC Harinath

Abstract Full Text PDF