Effects of novel auto-inducible medium on growth, activity and CO2 capture capacity of Escherichia coli expressing carbonic anhydrase

A glucose-based auto-inducible medium (glucose-AIM) has been developed to enhance both growth and expression of lac operon-linked carbonic anhydrase (CA) expression in a recombinant strain of Escherichia coli. When the E. coli expressing CA was grown on various media, the glucose-based auto-inducible medium (glucose AIM) resulted in a CA activity of 1022 mU OD600 nm− 1 mL− 1 at 24 h and a specific growth rate of 0.082 h− 1. The CA activity was four to fourteen times higher than those by LB-IPTG. The E. coli expressing CA grown on the glucose-AIM showed highest activity at pH 8.5 while it kept high stability up to 40 °C and an inlet CO2 concentration of 6%. These findings indicate that the glucose-AIM would be a cost-effective medium to support high cell growth, CA activity and stability for effective CO2 capture.