Isolation and biochemical characterization of novel acid phosphatase and zinc-dependent acid phosphatase from the chicken's brain

Int J Biol Macromol. 2024 May;266(Pt 2):131339. doi: 10.1016/j.ijbiomac.2024.131339. Epub 2024 Apr 3.

Abstract

The AcPase exhibits a specific activity of 31.32 U/mg of protein with a 728-fold purification, and the yield of the enzyme is raised to 3.15 %. The Zn2+-dependent AcPase showed a purification factor of 1.34 specific activity of 14 U/mg of proteins and a total recovery of 5.14. The SDS-PAGE showed a single band corresponding to a molecular weight of 18 kDa of AcPase and 29 kDa of Zn2+-dependent AcPase. The AcPase enzyme has shown a wide range of substrate specificity for p-NPP, phenyl phosphate and FMN, while in the case of ZnAcPase α and β-Naphthyl phosphate and p-NPP were proved to be superior substrates. The divalent metal ions like Mg2+, Mn2+, and Ca2+ increased the activity, while other substrates decreased the enzyme activity. The Km (0.14 mM) and Vmax (21 μmol/min/mg) values of AcPase were higher than those of Zn2+-AcPase (Km = 0.5 mM; Vmax = 9.7 μmol/min/mg). The Zn2+ ions activate the Zn2+-AcPase while Fe3+, Al3+, Pb2+, and Hg2+ showed inhibition on enzyme activity. Molybdate, vanadate and phosphate were found to be competitive inhibitors of AcPase with Ki values 316 μM, 185 μM, and 1.6 mM, while in Zn2+-AcPase tartrate and phosphate also showed competitive inhibition with Ki values 3 mM and 0.5 mM respectively.

Keywords: Acid phosphatases; Gallus domesticus; Polyacrylamide gel electrophoresis.

MeSH terms

  • Acid Phosphatase* / chemistry
  • Acid Phosphatase* / isolation & purification
  • Acid Phosphatase* / metabolism
  • Animals
  • Brain* / enzymology
  • Chickens*
  • Hydrogen-Ion Concentration
  • Kinetics
  • Molecular Weight
  • Substrate Specificity
  • Zinc* / chemistry

Substances

  • Zinc
  • Acid Phosphatase