Improved Expression in Escherichia Coli and Stability of Halophilic β-Lactamase-Firefly Luciferase Fusion Protein

Abstract

Halophilic bacteria living in high salinity environments, i.e., oceans, salt lakes salty foods, etc., produce halophilic enzymes that show high aqueous solubility, strong resistance to protein aggregation, and high refolding and renaturation efficiency. These properties are associated with their abundant net negative charges. Firefly (Photinus pyralis) luciferase is widely used in a variety of applications, but known as an aggregation-prone protein with low stability. Here, we demonstrated that halophilic β-lactamase confers to the firefly luciferase higher solubility and stability as a His-β-lactamase-luciferase fusion protein construct.