“…The chemical constitution common to all known living cells is apparently restricted to the ten elements C, H, N, O, P, S, K, Mg, Zn and Mn. [1] Certain elements are present in the composition of most species but absent in others, thus Escherichia coli is devoid of Na and Cl, Saccharomyces cerevisiae of Mo and Lactobacillus plantarum of Fe. The templated biosynthesis of informational polymers proceeds by exclusively incorporating the C, H, N, O, P subset in nucleic acids (as catalyzed by RNA and DNA polymerases) and the C, H, N, O, S subset in proteins (as catalyzed by ribosomes).…”