One approach toward solving these problems is through directed evolution whereby mutations are introduced into the DNA of the native hydrogenase (13, 18-21). Directed evolution is a technique that mimics natural evolution in that multiple mutations are created and tested for enhanced traits. Albeit on a shorter timescale, the proteins with evolved mutations are submitted to repeat cycles of evolutionary pressure.
In this talk I will review my research toward optimizing algal hydrogenases. Specifically, I will review two aspects of my work. The initial work with directed evolution of bacterial hydrogenases that resulted in proof of principle that hydrogenases can be mutated and improved. Secondly, I will show the results of our work with the expression of algal hydrogenases in Chlamydomonas reinhardtii. Ultimately, a mutant with increased hydrogen production and a higher tolerance to oxygen will be transformed into C. reinhardtii, which will facilitate a practical method of producing hydrogen for use as a commercial fuel source.
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