|
type |
Journal Article |
authors |
Sumi, C.; Ichinose, H.; Nagatsu, T. |
title |
Characterization of recombinant human aromatic L-amino acid decarboxylase expressed in COS cells |
journal |
J Neurochem |
Activity |
4.1.1.28 |
ui |
90347447 |
year |
(1990) |
volume |
55 |
number |
3 |
pages |
1075-8. |
| |
keywords |
5-Hydroxytryptophan/metabolism |
abstract |
The expression vector containing the full-length cDNA of human aromatic L-amino acid decarboxylase (EC 4.1.1.28) was transfected in COS cells by a modified calcium phosphate coprecipitation method. The cells transfected with plasmids that had a true direction of the cDNA gave a major immunoreactive band at 50 kDa. This expressed enzyme catalyzed the decarboxylation of L-3,4-dihydroxyphenylalanine (L-DOPA), L-5- hydroxytryptophan (L-5-HTP) and L-threo-3,4-dihydroxyphenylserine. The optimal pH of the enzyme activity with L-DOPA as a substrate was 6.5, whereas the enzyme had a broad pH optimum when L-5-HTP was used as a substrate. Addition of pyridoxal phosphate to the incubation mixture greatly enhanced the activity for both L-DOPA and L-5-HTP. |
last changed |
2002/11/12 16:17 |
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