Lipid reduction to improve clarification and filterability during primary recovery of intracellular products in yeast lysates using exogenous lipase

BACKGROUND The yeast Pichia pastoris is a popular host organism for production of a range of biological products, several of which are intracellular. The disruption of yeast cells by homogenization also releases large quantities of lipids, which can foul the downstream membranes and chromatography matrices used for purification. This work examines lipid removal from yeast cells following homogenization by enzymatic degradation and its impact on the performance of the subsequent centrifugation and filtration. RESULTS Lipase treatment of cell homogenate at 37 degrees C for 2 h, followed by clarification using a scaled-down mimic of disc stack centrifugation, resulted in a 6.5-fold improvement in solids removal when compared to untreated feed material. The lipase-treated and untreated materials that had undergone initial centrifugation were then tested for filtration performance by passing the material through a 0.45 mu m polyethylene sulfone membrane under constant flux. A 50% increase in throughput was observed in comparison to the untreated material. CONCLUSION These proof-of-concept data suggest enzymatic digestion of lipids, analogous to the widely performed DNA reduction using nucleases, could be a valuable process improvement strategy. (c) 2021 The Authors. Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI).

Automated summary

This study demonstrates that enzymatic degradation of lipids from yeast cells can significantly improve solid removal efficiency and increase membrane throughput, suggesting a valuable process improvement strategy for bioproduction.