TY - JOUR
AU - Inui, Takashi
AB - Lipocalin-type prostaglandin D synthase (L-PGDS) binds various hydrophobic small molecules. Since we aim to use human L-PGDS as a carrier in a drug delivery system (DDS) for poorly water-soluble drugs, quality control of the protein is indispensable. In this study, we investigated the thermodynamic stability of human L-PGDS under various pH conditions. Differential scanning calorimetry revealed that the thermal unfolding of L-PGDS was an almost-reversible two-state transition between the native and unfolded states over the pH range from 2.5 to 7.4. The linear relationship of ΔH(Tm) to Tm in this pH range gave a heat capacity change (ΔCp) of 4.76 kJ/(K·mol), which was small compared to those commonly found in globular proteins. The temperature-dependent free energy of unfolding, ΔG(T), specified by Tm, ΔH(Tm) and ΔCp, showed a pH dependence with the highest value at pH 7.4 closest to the isoelectric point of 8.3. The small value of Cp resulted in a large value of ΔG(T), which contributed to the stability of the protein. Taken together, these results demonstrated that human L-PGDS is sufficiently thermostable for storage and practical use and can be useful as a delivery vehicle of protein-based DDS.
TI - Thermodynamic stability of human lipocalin-type prostaglandin D synthase under various pH conditions
JF - The Journal of Biochemistry
DO - 10.1093/jb/mvad016
DA - 2023-02-10
UR - https://www.deepdyve.com/lp/oxford-university-press/thermodynamic-stability-of-human-lipocalin-type-prostaglandin-d-lrYC9RTkiN
SP - 21
EP - 31
VL - 174
IS - 1
DP - DeepDyve
ER -