Low-carbon and overproduction of cordycepin from methanol using engineered Pichia pastoris cell factory.

Cordycepin, a nucleoside analog, is widely used in medicine and health products. However, the production of cordycepin from Cordyceps militaris faces the challenges of low productivity and high rate of greenhouse gas emissions. In this study, by optimizing the cordycepin biosynthesis pathway through promoter combination, Kozak sequence, and enzyme fusion, enhancing the methanol assimilation capacity in peroxisomes, adjusting the synthesis of NADPH and ATP, and combining the enhanced supply of adenosine and 3'-AMP, the cordycepin high-yield strain Pp29 was constructed, which produced 1551.44 mg/L cordycepin by shake-flask fermentation. In fed-batch fermentation, Pp29 achieved the highest yield (8.11 g/L, 67.64 mg/g DCW, and 1.35 g/L/d) to date in 10 L fermenter, and the CO2-eq emissions were 1.9-17.3 times lower than C. militaris and other yeast systems. This study provide basis for Pichia pastoris to be used as chassis cell for synthesizing cordycepin and other nucleoside analogs by methanol as carbon source.