FIG 1.

Expression of tyrosinase gene and melanin production in V. natriegens through IPTG induction. (A) Left, melanin production in M9 medium supplemented with 40 μg/ml CuSO₄ and 0.4 mg/ml l-tyrosine after tyrosinase was induced in rich medium; right, melanin production from the filtered supernatant supplemented with CuSO₄ and l-tyrosine after the induced cells were incubated in M9 medium for 15 min. (B) Kinetics of melanin production in M9 (•) and LBv2 (♦) media supplemented with 40 μg/ml CuSO₄ and 0.4 mg/ml l-tyrosine after tyrosinase was induced in rich medium. (C) Effect of l-tyrosine concentration (in milligrams per milliliter) on melanin production in M9 medium. Graphs in panels B and C represent the averages of the results from five independent experiments. (D) Syntheses of melanin variants with tripeptide precursors. IPTG-induced V. natriegens/pJV-Tyr1 cells were transferred into M9 medium supplemented with CuSO₄ and 5 mM tripeptides and incubated at 37°C for 1 h.