The enzyme tyrosinase catalyses the oxidation of several aromatic substrates that generate polymers called melanins. This enzyme and its products have several potential industrial applications. Tyrosinases from different biological sources have been utilized for the synthesis of L-3,4-dihydroxyphenylalanine (L-dopa) and for the removal of phenolic compounds from wastewaters. Melanins have physicochemical properties that allow them to act as UV absorbers, cation exchangers, amorphous semiconductors, X- and γ-ray absorbers. With the purpose of generating Escherichia coli strains with the capacity of synthesizing a tyrosinase and melanins, the gene melA from the bacterium Rhizobium etli was amplified using PCR and cloned to obtain plasmid pTrcmelA. Recombinant E. coli strain W3110/pTrcmelA synthesized a dark pigment identified as melanin. The recombinant tyrosinase expressed intracellularly in E. coli was purified and characterized. The K_m for L-dopa and L-tyrosine were determined as 2.44 mM and 0.19 mM, respectively. Temperature and pH for maximum activity were 50^oC and 6.5-7.5, respectively. A parametric study was conducted to define conditions for achieving high yields in the conversion of tyrosine to melanin using W3110/pTrcmelA as a biocatalyst. Batch aerobic fermentor cultures were performed to study the effect of melA gene inducer concentration (IPTG), temperature and pH on melanin production. Under optimum conditions, 0.1 mMol of IPTG, culture temperature of 30ºC, and changing pH from 7.0 to 7.5 during the production phase, a 100% yield conversion of tyrosine into melanin was observed. In addition, tyrosine-feeding experiments allowed us to obtain a high titer (6 g/l) of melanin.