The Protein Journal

, Volume 26, Issue 5, pp 335–348

Biochemical Characterization of a S-glutathionylated Carbonic Anhydrase Isolated from Gills of the Antarctic Icefish Chionodraco hamatus

  • Antonia Rizzello
  • M. Antonietta Ciardiello
  • Raffaele Acierno
  • Vito Carratore
  • Tiziano Verri
  • Guido di Prisco
  • Carlo Storelli
  • Michele Maffia
Article

DOI: 10.1007/s10930-007-9076-1

Cite this article as:
Rizzello, A., Ciardiello, M.A., Acierno, R. et al. Protein J (2007) 26: 335. doi:10.1007/s10930-007-9076-1

Gill cytoplasmic carbonic anhydrase of the haemoglobinless Antarctic icefish Chionodraco hamatus (Ice-CA) was directly sequenced and consists in 259 residues with an acetylated N-terminus. The molecular mass, deduced from the sequence, was 28.45 kDa, while mass spectrometry analysis of the native protein gave higher values. Treatment with dithiothreitol abolished this difference, indicating possible post-translational modifications. Isoelectric focusing analysis of Ice-CA suggested S-thiolation, which was identified as S-glutathionylation by immunostaining. Deglutathionylated Ice-CA maintained the anhydrase activity but showed higher susceptibility to hydrogen peroxide, suggesting that glutathione binding to Cys residues may have a role in the defence against oxidative damage. Ice-CA is characterized by lower thermal stability, higher activity and lower activation energy than its homologue gill CA of the temperate European eel, confirming the adaptation of the catalytic capacity to low temperatures. Alignment of Ice-CA with homologous enzymes from other fish shows high identity; the enzyme is grouped with a previously described fish CA monophyletic clade although Ice-CA shows several characteristics that can increase protein-solvent interaction and structural flexibility.

Keywords

Gill carbonic anhydraseAntarctic fishhaemoglobinless Chionodraco hamatusamino acid sequenceS-glutathionylation

Abbreviations

CA

carbonic anhydrase

Ice-CA

icefish carbonic anhydrase

DTT

dithiothreitol

DTNB

5,5′-dithio-bis 2-nitrobenzoic acid

IEF

isoelectric focusing

RBC

red blood cell, erythrocyte

ROS

reactive oxygen species

SOD

superoxide dismutase

CAT

catalase

GPx

glutathione peroxidase

Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  • Antonia Rizzello
    • 1
  • M. Antonietta Ciardiello
    • 2
  • Raffaele Acierno
    • 1
  • Vito Carratore
    • 2
  • Tiziano Verri
    • 1
  • Guido di Prisco
    • 2
  • Carlo Storelli
    • 1
  • Michele Maffia
    • 1
  1. 1.Laboratory of General Physiology, Department of Biological and Environmental Science and TechnologyUniversity of SalentoLecceItaly
  2. 2.Institute of Protein BiochemistryC.N.R.NaplesItaly