The invention provides a
yeast engineering strain for synthesizing
melatonin as well as a construction method and application of the
yeast engineering strain, and relates to the technical field of
genetic engineering and microbial
fermentation engineering. According to the invention, a novel
yeast engineering bacterium for synthesizing
melatonin is constructed, wherein the novel yeast engineering bacterium is used for overexpressing arylalkylamine N-acetyl
transferase, 5-hydroxytryptophan decarboxylase,
tryptophan hydroxylase, N-acetyl
serotonin methyltransferase, 6-pyruvoyl
tetrahydrobiopterin synthetase, ink
pterin reductase, 4a-hydroxytetrahydrobiopterin
dehydratase and dihydropterin
reductase. Under the
fermentation process that 1g / L
tryptophan is externally added, the content of
melatonin in a
fermentation product obtained by the yeast engineering
bacteria reaches 14.32 mg / L, and 17.48 mg / g DCW. Under the condition that 4g / L
tryptophan is added, 5L fermentation tank culture is carried out, and the content of melatonin in a fermentation product obtained by the yeast engineering
bacteria reaches 91.82 mg / L. The engineered yeast provided by the invention can significantly increase the yield of melatonin, is expected to realize industrial
mass production of melatonin, and has good application value and commercial value.