High Level Expression and Purification of PZase and Study of Osmolyte Effects on its Activity

Tuberculosis is a common infectious disease caused by various strains of mycobacteria, usually Mycobacterium tuberculosis. The emergence of strains of M.tuberculosis resistant to drug is an important public health problem. Pyrazinamide (PZA) is an important first-line drug used for the short-course treatment of tuberculosis in combination with isoniazid and rifampin. Previous studies have shown that the bacterial enzyme pyrazinamidase (PZase) is required to convert PZA to pyrazinoic acid (POA), which is toxic to M. tuberculosis. Therefore, reduction in PZase activity and stability ormutation in pnc gene causes resistance to PZA resistance. In this work, we have cloned, overexpressed, purified and characterized the activity of PZase in aqueous osmolytes solutions (Glycerol, Betain, Sorbitol, Sucrose, Urea and Guanidin Hydrochlorid).Results: Our results showed that the Glycerol solution increases, whereas lowconcentrations of Urea and GuHCl decrease the PZase activity, and the other osmolytes have no significant effect on protein. Discussion: glycerol could protect both the tertiary and secondary structure of enzyme from unfolding and thus keep the protein from further aggregation And inactivation.

کلیدواژه ها:

Tuberculosis ، Pyrazinamidase ، Drug Resistance ، Enzyme stabilization