Biohydroxylation reactions catalyzed by enzymes and whole-cell systems

The biohydroxylation of a number of cyclic substrates (3-24) containing aro matic side chains was used to compare substrate specificity and selectivity of hydroxylation using microbial enzymes and whole-cell biocatalysts. In g eneral, the regioselectivity of reaction was remarkably similar between the different catalysts in that little aromatic or benzylic, but significant a liphatic hydroxylation was observed. However, a more detailed investigation of isolated products showed complementary substrate specificity, functiona l group compatibility, and regioselectivity of hydroxylation. Substrate spe cificity and regioselectivity could be further modulated by small changes t o the nature of the aromatic side chain, which appears to play an important role in substrate recognition, (C) 1999 Academic Press.