P. Ruizvazquez et al., CHARACTERIZATION OF SEPIAPTERIN REDUCTASE-ACTIVITY FROM DROSOPHILA-MELANOGASTER, Comparative biochemistry and physiology. B. Comparative biochemistry, 113(1), 1996, pp. 131-136
A kinetic study of Drosophila melanogaster sepiapterin reductase has b
een done. The apparent K-m for sepiapterin has been estimated as 153 m
u M. N-acetyldopamine, N-acetylserotonin, and N-methoxyacetylserotonin
have shown to be noncompetitive inhibitors for the Drosophila sepiapt
erin reductase. The K-i obtained were 40 mu M, 127 mu M and 87 mu M, r
espectively. Chromatofocusing of Drosophila crude extracts has shown o
nly one peak with sepiapterin reductase activity, corresponding to pI
6.0. A study of the activity in different eye-color mutant strains rev
ealed significantly decreased levels in clot, red Malpighian tubules a
nd garnet.