Comparison in effect of different metal ions, pH and reducing agent on the protease activity in human hyper mature and mature cataract

Abstract

This study was undertaken to isolate and characterize the protease activity of human eye lens sample of mature and hyper mature cataract. Samples were collected just after surgery of the cataract lens and were stored at −20 °C. The total protein extract was isolated from 5 samples in each case (mature and hyper mature cataract) and clear supernatant obtained after centrifugation was used as an enzyme source. The optimum pH for the proteases of mature cataract was 7.5 while the proteases of hyper mature cataract were recorded for maximum activity at pH 5.5 and 7.5. The optimum temperature for both enzyme sources was 50 °C. Effect of different metal ions such as potassium, lead, silver, zinc and borate was studied. In each case protease activity was increased. Reducing agent e.g. β mercaptoethanol also caused an increase in activity indicating the involvement of sulfhydryl groups. Protease activity was also located on agar plates.

Novel Fibrinolytic Enzyme by Scopulariopsis brevicaulis OS 3456: Production, Characterization, In vitro, and In vivo Activity

“…It was found that the addition of ß-mercaptoethanol, Mn 2+ , Ca 2+ , and Mg 2+ at 5mM concentration significantly increased the enzyme activity by 137.1, 51.6, 14.4, and 10.3%, respectively, acting as activators. The activity increased in the presence of β-mercaptoethanol as a reducing agent, indicating the involvement of sulfhydryl groups (Sami et al, 2007). On the contrary, EDTA, PMSF, Cu 2+ , and Zn 2+ reduced the enzyme activity, revealing that these cations bind to carboxyl groups that may be an essential component of the active site of the enzyme.…”