Biochemistry (Moscow)

, Volume 76, Issue 6, pp 694–701

Purification, primary structure, and properties of Euphorbia characias latex purple acid phosphatase

  • F. Pintus
  • D. Spano
  • S. Corongiu
  • G. Floris
  • R. Medda
Article

DOI: 10.1134/S0006297911060101

Cite this article as:
Pintus, F., Spano, D., Corongiu, S. et al. Biochemistry Moscow (2011) 76: 694. doi:10.1134/S0006297911060101

Abstract

A purple acid phosphatase was purified to homogeneity from Euphorbia characias latex. The native protein has a molecular mass of 130 ± 10 kDa and is formed by two apparently identical subunits, each containing one Fe(III) and one Zn(II) ion. The two subunits are connected by a disulfide bridge. The enzyme has an absorbance maximum at 540 nm, conferring a characteristic purple color due to a charge-transfer transition caused by a tyrosine residue (Tyr172) coordinated to the ferric ion. The cDNA nucleotide sequence contains an open reading frame of 1392 bp, and the deduced sequence of 463 amino acids shares a very high degree of identity (92–99%) to other purple acid phosphatases isolated from several higher plants. The enzyme hydrolyzes well p-nitrophenyl phosphate, a typical artificial substrate, and a broad range of natural phosphorylated substrates, such as ATP, ADP, glucose-6-phosphate, and phosphoenolpyruvate. The enzyme displays a pH optimum of 5.75 and is inhibited by molybdate, vanadate, and Zn2+, which are typical acid phosphatase inhibitors.

Key words

acid phosphataseEuphorbia characiasiron ionmetalloenzymespurple phosphatasezinc ion

Abbreviations

AP

acid phosphatases

ELPAP

Euphorbia latex purple acid phosphatase (protein)

PAPs

purple acid phosphatases

p-NPP

4-nitrophenyl phosphate

RT-PCR

reverse transcription-polymerase chain reaction

SDS-PAGE

sodium dodecyl sulfate polyacrylamide gel electrophoresis

Copyright information

© Pleiades Publishing, Ltd. 2011

Authors and Affiliations

  • F. Pintus
    • 1
  • D. Spano
    • 1
  • S. Corongiu
    • 1
  • G. Floris
    • 1
  • R. Medda
    • 1
  1. 1.Department of Applied Sciences in BiosystemsUniversity of CagliariCagliariItaly