Stimulation of staphylococcus aureus ligase enzyme by magnesium ion

Abstract

Ligases enzymes were discovered as a member of the nucleotidyl transferase family. Here in this paper, DNA Ligase is extracted from S. aureus works with the cofactor NAD+ to make a phosphodiester bond and reform between the 3’hydroxyl and 5’phosphate DNA end. Staphylococcus aureus-DNA Ligases Enzyme type A (SLE-A) contains two essential domains; NTase and OB-fold domain, which are the most essential domains for the enzyme function. The main aim of the study is to investigate the activity of SLE-A in the presence of magnesium ion (Mg+2) by evaluating several kinetic parameters on a time course. The result showed that SLE-A has optimal activity at 500 µM of Mg+2. Furthermore, the low number of Equilibrium Association Constant (Km value) explains the binding affinity between DNA ligase of Staphylococcus aureus SLE-A enzyme and Mg+2 ion was very high and sold.