1 research outputs found
Isolation and Sequencing of Salsolinol Synthase, an Enzyme Catalyzing Salsolinol Biosynthesis
Salsolinol (1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline),
a derivate of dopamine, is suspected to be the most probable neurotoxin
in the degeneration of dopaminergic neurons. Numerous hypotheses regarding
its pathophysiological roles have been raised, especially related
to Parkinson’s disease and alcohol addiction. In the mammalian
brain, salsolinol may be enzymatically synthesized by salsolinol synthase
from dopamine and acetaldehyde. However, the direct evidence of its
biosynthesis was still missing. In this study, we purified salsolinol
synthase from rat brain by a systematical procedure involving acid
precipitation, ultrafiltration, and hydrophilic interaction chromatography.
The molecular weight of salsolinol synthase determined by MALDI-TOF
MS is 8622.29 Da, comprising 77 amino acids (MQIFVKTLTG KTITLEVEPS
DTIKNVKAKI QDKEGIPPDQ QRLIFAGKQL EDGRTLSDYN IQKKSTLHLV LRLRVDY). Homology
analysis showed that the enzyme is a ubiquitin-like protein, with
a difference of four amino acids, which suggests it is a novel protein.
After it was overexpressed in eukaryotic cells, the production of
salsolinol was significantly increased as compared with control, confirming
the catalytic function of this enzyme. To our knowledge, it is the
first systematic purification and sequencing of salsolinol synthase.
Together, this work reveals a formerly anonymous protein and urges
further exploration of its possible prognostic value and implications
in Parkinson’s disease and other related disorders