Transgenic Expression of a Bacterial Thermophilic Amylase in the Chlamydomonas reinhardtii Chloroplast to Facilitate Algal Biofuel Production

This study investigated expression of a thermophilic amylase (arAmyBH) from hyperthermophilic bacterium Thermotoga neapolitana into Chlamydomonas reinhardtii chloroplast to facilitate in vivo starch hydrolysis for algal biofuel production. The expression and accumulation of the recombinant protein in the algal chloroplast were verified by Western blot analysis. The recombinant arAmyBH was purified using Ni-NTA purification system. The optimum pH and temperature of arAmyBH were 5.5 and 60 °C, respectively. The enzymatic hydrolysis of the algal starch demonstrated that with supplemental commercial alpha-amylase, the transformant completely converted starch into reducing sugars in vivo at an elevated temperature.