Perspectives of biotechnological production of l-tyrosine and its applications

The aromatic amino acid l-tyrosine is used as a dietary supplement and has promise as a valuable precursor compound for various industrial and pharmaceutical applications. In contrast to chemical production, biotechnological methods can produce l-tyrosine from biomass feedstocks under environmentally friendly and near carbon-free conditions. In this minireview, various strategies for synthesizing l-tyrosine by employing biocatalysts are discussed, including initial approaches as well as more recent advances. Whereas early attempts to engineer l-tyrosine-excreting microbes were based on auxotrophic and antimetabolite-resistant mutants, recombinant deoxyribonucleic acid technology and a vastly increasing knowledge of bacterial physiology allowed recently for more targeted genetic manipulations and strain improvements. As an alternative route, l-tyrosine can also be obtained from the conversion of phenol, pyruvate, and ammonia or phenol and serine in reactions catalyzed by the enzyme tyrosine phenol lyase.