codes(gene_a, enzyme_a).
codes(gene_b, enzyme_b).
codes(gene_c, enzyme_c).
codes(gene_d, enzyme_d).
codes(gene_e, enzyme_e).
codes(gene_f, enzyme_f).
codes(gene_g, enzyme_g).
codes(gene_h, enzyme_h).
codes(gene_i, enzyme_i).
codes(gene_j, enzyme_j).
codes(gene_k, enzyme_k).
codes(gene_l, enzyme_l).
codes(gene_m, enzyme_m).