The third and final day of Synthetic Biology 3.0 in Zürich, Switzerland is designed to address applications for synthetic bio. I was just blown away by a nice demonstration in the first talk this morning by Michael Famulok, of the University of Bonn.
Famulok works on RNA catalysts, or ribozymes, working to design and refine them via selection in a test tube, in some ways modelling the conditions that might have existed in an early RNA world – of course, in a much accelerated way. He gave some indication of the range of molecules such a system could possibly choose from.
In a 100 nucleotide sequence of RNA, there are obviously 4^100 possible combinations of sequence. That’s 10ˆ60 RNA molecules each 100 nucleotides long. That many RNA strands would weigh something on the order of 10^38 kilograms which is roughly the mass of the Milky Way. Wow!
In vitro selection is a powerful process, but it can’t possibly test the full combinatorial space of an RNA sequence this size.