One strain of modified E. coli is capable of converting glucose into cis, cis-muconic acid (Scheme 6), which is hydrogenated to form adipic acid. In unmodified E. coli glucose is trans- formed into the amino acids L-phenyl- alanine, L-tyrosine, and L-tryptophan (Scheme 6). Inter mediates in the production of these amino acids include EAP DAHP DHQ,
3-dehydroshikimic acid (DHS), and shikimic acid. The genetically altered E. coli is incapable of converting DHS to shikimic acid. Instead, modified E. coli converts DHS into protocatechic acid (PCA), PCA to catechol, and catechol to cis, cis-muconic acid. cis,cis-Muconic acid is then hydrogenated over a catalyst to produce adipic acid.