Utilization of oxygen uptake rate to assess the role of glucose and glutamine in the metabolism of infected insect cell cultures

摘要

On-line monitoring is a valuable tool for designing operation strategies.In this work,oxygen uptake rate (OUR) was measured on-line in infected insect cell cultures.OUR increased up to 80% when cultures were infected and glucose was present.In the absence of glucose,OUR did not increase and low yields (9.7 x 10~6 U/cell) of recombinant rotavirus VP8 were obtained.Restoration of the initial glucose concentration at the time of infection increased 10 times the VP8 yield.Glutamine feeding further increased VP8 yields.Glucose or glutamine depletion after infection caused a sudden decrease in OUR.Such a decrease was 19 times faster when glutamine was depleted than when glucose was depleted,indicating that OUR can be utilized to assess which and when either of these two nutrients is exhausted.Feeding strategies were implemented based on OUR measurements.This work shows that OUR can be utilized to take corrective actions for reestablishing recombinant protein yields.Selective glucose and glutamine feeding resulted in recombinant protein yields similar to those obtained by complete medium exchange upon infection,but at reduced expenses and simplified operation.