The influence of Cadaverine on the structure, stability, and activity of acid phosphatase

Abstract

This research aimed to study the interaction between cadaverine and acid phosphatase. Therefore, the structural alterations of acid phosphatases that were caused by Cadaverine, were measured through fluorescence spectroscopy and UV-Visible spectroscopy. The influence of Cadaverine on the acid phosphatase activity was then investigated at the pH level of 4.8 and the temperature of 310K; also, a sodium citrate buffer was used. The process of binding Cadaverine to acid phosphatase was spontaneous according to the results obtained through fluorescence spectroscopy (ΔG° < 0). The fluorescence of acid phosphatase was decreased through Cadaverine. For the static quenching, the Stern–Volmer quenching constant (KSV from 1.8×103Lmol−1to1.6×103Lmol−1) decreased with an increase in temperature. Therefore, the fluorescence quenching mechanism was via static quenching. The thermal stability of acid phosphatase was been reduced by increasing the concentration of Cadaverine (Tm from 342 K to 337 K). Some data (CD) were obtained regarding the alterations in the α-helicity (from 10.8 to 15.6) increase and the β-sheet (from 30.2 to 27.0) decrease, after binding acid phosphatase to Cadaverine. Molecular docking results also showed the Gibbs free energy negative value for binding Cadaverine to phosphatase acid. In comparison, experiments on fluorescence spectroscopy and docking showed that hydrogen bonds and van der Waals interactions played a major role in the complex formation (ΔH° < 0 and ΔS° < 0). Overall, results showed that Cadaverine could change the acid phosphatase activity and structure.