LAUSR

Pichia pastoris is an expression platform widely employed for foreign protein expression, while it is unknown how the global lipids profiles changed during the cultivation process, which is crucial for fermentation optimization and chassis design. Therefore, the present study aimed to reveal the diverse lipids profiles of P. pastoris controlled by constitutive promoter of glyceraldehyde-3-phosphate dehydrogenase gene and to unravel their change at the lag, logarithmic, stationary and death phases, using ultra-performance liquid chromatography/Nano-electrospray-mass/mass spectrometry. 240 lipid species across 11 lipids classes were detected, including various glycerolipids, glycerophospholipids and sphingolipids. Pichia cells displayed high diversity and variability of lipids in lipids profile, relative intensity, PI/PS ratio, fatty acid chain length and unsaturation degree. Notably, increase of unsaturated TG level was accompanied by rise of malondialdehyde level under oxidative stress. The increased ceramide with long fatty acid chain could be a key feature at death phase. The present work deepened our understanding of the physiology of P. pastoris during cultivation and provided valuable information for further improvement of P. pastoris expression system.