Abstract

Staphylococcus aureus (S. aureus) is a versatile bacterium which exhibits multiple antibiotic resistances. To ameliorate the undesirable diseases causing potential, there is a need to design a protective vaccine capable of stimulating immune response against this pathogen. In a similar study in our laboratory, reverse vaccinology approach was used to nominate potential vaccine candidate genes against S. aureus. Zinc Metalloproteinase Aureolysin (aur) gene was one of the nominated genes based on that previously published in-silico study. The objective of this study is the cloning, expression,  purification of aur gene and testing the aur protein reactivity with serum antibodies collected from groups of human patients with confirmed Staphylococcal disease. Cloning was done in pH6HTN His6HaloTag® vector and it was expressed in E. coli BL21 (DE3) using these conditions; 0.5 mM Isopropyl β-D-1-thiogalactopyranoside (IPTG) for 4 h at 37°C. Purification was carried out by Immobilized Metal Affinity Chromatography (IMAC). The his-tag aur protein was detected at ~86 KDa as a single band after western blot assay and was successfully reacted with antibodies obtained from humans infected with S. aureus. The results encourage further testing of aur protein as a potential vaccine candidate for S. aureus.

Key words: Staphylococcus aureus, Zinc Metalloproteinase Aureolysin (aur), cloning, expression.