Correlation between BHK Cell Specific Productivity and Metabolism

Abstract

A rBHK21 clone producing an antibody/cytokine fusion protein was used to study the dependence of cell metabolism on the glucose and glutamine levels in the culture medium. Results indicate that glucose and glutamine consumptions and lactate and ammonia productions show hyperbolic behaviors. The estimated values for K_m were 1.39±0.11 mM for lactate production as a function of glucose and 0.59±0.17 and 0.15 ±0.04mM for ammonia production as a function of glutamine, at glucose concentrations of 0.05 and 1.0 g l^- respectively. At very low glucose concentrations the glucose to lactate yield decreased markedly, showing a metabolic shift towards lower glucose fermentation. At very low glutamine concentrations, the glutamine to ammonia yield increases, showing a more efficient glutamine metabolism. The cell specific productivity can be increased significantly by manipulating nutrient concentrations.