Prospects
With the body of knowledge available, large-scale application of Synechocystis strains, metabolically reprogrammed according to the Photanol concept or for hydrogen production, as outlined above, seems a challenging but feasible approach. Here, we will not discuss technical aspects of large-scale culturing of unicellular photosynthetic organisms but it should be noted that major progress is being made in this field with respect to cost reduction, stability, and efficiency improvements in effective light capturing, see for example [41,42 ,43]. An interesting development in this respect is the application of new emerging LED-technologies as an additional, low-energy artificial supply of light with optimal properties for photosynthesis [44]. Another important development is the work to increase photosynthetic efficiency in mass cultures through the modulation of antenna size [45 ].