Propeptide processing and proteolytic activity of proenzymes of the Staphylococcal and Enterococcal GluV8-family protease.

Proenzymes with various lengths of propeptides have been observed in GluV8 from Staphylococcus aureus and GluSE from S. epidermidis. However, the production mechanism of these proenzymes and roles of truncated propeptides have yet to be elucidated. Here we demonstrate that shortening of propeptide commonly occurs in an auto-catalytic manner in GluV8-family members, including those from coagulase negative Staphylococci and Enterococcus faecalis. Accompanied with propeptide shortening, the pro-mature junction (Asn/Ser-1-Val1) becomes more susceptible towards the hetero-catalytic maturation enzymes. The auto-catalytic propeptide truncation is not observed in Ser169Ala inert molecules of GluV8-family members. A faint proteolytic activity of proenzymes from Staphylococcus caprae and E. faecalis is detected. In addition, proteolytic activity of proenzyme of GluV8 carrying Arg-3AlaAsn-1 is demonstrated with synthetic peptide substrates LLE/Q-MCA. These results suggest that GluV8-family proenzymes with shortened propeptides intrinsically possess proteolytic activity and are involved in the propeptide shortening that facilitates the final hetero-catalytic maturation.

Magnesium sulphate versus diazepam in the management of eclampsia.

This clinical trial was conducted to compare the anticonvulsant response of magnesium sulphate and diazepam in the management of eclampsia. The study was carried out at the eclampsia unit of Dhaka Medical College Hospital during the period from October, 1995 to January, 1996. Two hundred consecutive admitted patients were recruited for the study and randomly assigned to two treatment groups: magnesium sulphate and diazepam. One hundred patients received injection magnesium sulphate and another one hundred received injection diazepam. All patients of both the group were matched for baseline characteristics. Convulsion was controlled in 95% of the patients of magnesium sulphate group and 74% of the patients of diazepam group (p < .0005). The mean controlling time is also significantly lower in magnesium sulphate group than diazepam group (8.50 hours vs 9.39 hours). Patients of magnesium sulphate group regain consciousness much earlier (mean time 20.62 hrs.) than the patients of diazepam group (mean time 40.62 hrs.). No significant difference was observed in controlling blood pressure and foetal outcome. The study finding shows that magnesium sulphate has some advantage over diazepam in controlling convulsion and regaining consciousness. If magnesium sulphate can be made available in the market by local production it may be recommended to use this drug in the primary health care without any hazzard before referring to other hospital.