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However, an analysis by Ekland suggests that in the sequence space of 220 nucleotide long RNA sequences, a staggering 2.5 x 10^112 sequences are efficent ligases [12]. Not bad for a compound previously thought to be only structural. Going back to our primitive ocean of 1 x 10^24 litres and assuming a nucleotide concentration of 1 x 10-7 M [23], then there are roughly 1 x 10^49 potential nucleotide chains, so that a fair number of efficent RNA ligases (about 1 x 10^34) could be produced in a year, let alone a million years. The potential number of RNA polymerases is high also; about 1 in every 10^20 sequences is an RNA polymerase [12]. Similar considerations apply for ribosomal acyl transferases (about 1 in every 10^15 sequences), and ribozymal nucleotide synthesis [1, 6, 13]. Similarly, of the 1 x 10^130 possible 100 unit proteins, 3.8 x 10^61 represent cytochrome C alone! [29] There's lots of functional enyzmes in the peptide/nucleotide search space, so it would seem likely that a functioning ensemble of enzymes could be brewed up in an early Earth's prebiotic soup. So, even with more realistic (if somewhat mind beggaring) figures, random assemblage of amino acids into "life-supporting" systems (whether you go for protein enzyme based hypercycles [10], RNA world systems [18], or RNA ribozyme-protein enzyme coevolution [11, 25]) would seem to be entirely feasible, even with pessimistic figures for the original monomer concentrations [23] and synthesis times.