Dependence between the genome size (the total number of encoded proteins) and the number of encoded enzymes. A. The total number of encoded enzymes with assigned four-digit EC numbers. B. The number of encoded non-homologous isofunctional enzymes. Prokaryotic genomes are indicated with diamonds, eukaryotic genomes are indicated with squares. The best fit lines were calculated separately for prokaryotes (blue) and eukaryotes (red).