Biochemistry (Moscow)

, Volume 76, Issue 6, pp 694–701

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

Authors

  • F. Pintus
    • Department of Applied Sciences in BiosystemsUniversity of Cagliari
  • D. Spano
    • Department of Applied Sciences in BiosystemsUniversity of Cagliari
  • S. Corongiu
    • Department of Applied Sciences in BiosystemsUniversity of Cagliari
  • G. Floris
    • Department of Applied Sciences in BiosystemsUniversity of Cagliari
    • Department of Applied Sciences in BiosystemsUniversity of Cagliari
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 phosphatase Euphorbia characias iron ion metalloenzymes purple phosphatase zinc 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