Kinetic and Thermodynamic Analysis of Thermal Unfolding of Recombinant Erythropoietin

概要

論文の詳細を見る
Thermal stress was used to assess the stability of recombinant human erythropoietin (EPO) derived from Chinese hamster ovary cells. In 20 mM phosphate at pH 7.0,this protein had a highly reversible thermal unfolding as observed by far UV circular dichroism (CD) and native gel analysis, with no indication of protein aggregation. It had a relatively low melting temperature at 53℃. Assuming a two-state transition, the observed reversibility permits thermodynamic analysis of the unfolding of EPO, which shows that the free energy of unfolding at 25℃ is only 6-7 kcal/mol. Upon heating to 79℃ over 30 min, however, this protein does undergo aggregation as assessed by native gel. In 20 mM phosphate and citrate at pH 7.0,the results are similar, i.e., EPO suffered a substantial aggregation, while it showed little aggregation in 20 mM Tris or histidine at pH 7.0 and 20 mM glycine at pH 6.3 under identical heat treatment.
社団法人日本農芸化学会の論文
2001-06-23