초록
<P>Hydroxytyrosol is a high-value-added compound with a variety of biological and pharmacological activities. In this study, a whole-cell catalytic method for the synthesis of hydroxytyrosol was developed: aromatic amino acid aminotransferase (TyrB), <SMALL>L</SMALL>-glutamate dehydrogenase (GDH), α-keto acid decarboxylase (PmKDC), and aldehyde reductase (YahK) were co-expressed in <I>Escherichia coli</I> to catalyze the synthesis of hydroxytyrosol from <SMALL>L</SMALL>-3,4-dihydroxyphenylalanine (<SMALL>L</SMALL>-DOPA). The plasmids with different copy numbers were used to balance the expression of the four enzymes, and the most appropriate strain (pRSF-<I>yahK</I>-<I>tyrB</I> and pCDF-<I>gdh</I>-<I>Pmkdc</I>) was identified. After determination of the optimum temperature (35 °C) and pH (7.5) for whole-cell catalysis, the yield of hydroxytyrosol reached 36.33 mM (5.59 g/L) and the space-time yield reached 0.70 g L<SUP>-1</SUP> h<SUP>-1</SUP>.</P><BR>[FIG OMISSION]</BR>