5-Hydroxytryptophan (5-HTP) is a vital precursor to significant neurotransmitters in mammals.Its medicinal value in treating neurological diseases gives it a broad market prospect.Enzymatic catalysis emerges as a promising production approach due to its high conversion rates, controllable reaction conditions, and eco-friendly nature.But challenges still exist, such as the costly and time-consuming purification of enzyme proteins.This study intend to improve 5-HTP expression, catalysis, and secretion to enhance the biotransformation of 5-HTP from tryptophan utilizing crude enzyme extract.The expression host was genetically modified to effectively block the degradation pathway of substrate and product.The introduction of truncation and solubility-enhancing fusion tags yielded the M11 enzyme mutant with optimal expression efficiency and improved thermal stability.Optimization of catalysis system parameters established the best catalytic conditions, enhancing enzyme catalysis efficiency.The M11 mutant catalyzed in the optimal reaction system produced 0.17 g/L of 5-HTP within 2 h, achieving an 85% conversion ratio.An efficient strategy for the extracellular release of enzyme proteins was developed by combining a green fluorescent protein variant with chemical release agents.The secretion efficiency achieved up to 90%, reducing the operational costs compared with traditional pure enzyme catalysis and offering a potential alternative for the industrial production of 5-HTP.
WU Meiqi
,
YU Shiqin
,
ZENG Weizhu
,
ZHOU Jingwen
. Efficient secretion of tryptophan hydroxylase for biotransformation of 5-hydroxytryptophan[J]. Food and Fermentation Industries, 2025
, 51(4)
: 11
-19
.
DOI: 10.13995/j.cnki.11-1802/ts.039073
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