Hemocyanin conformational changes associated with SDS-induced phenol oxidase activation

Sharon Baird, Sharon M. Kelly, Nicholas C. Price, Elmar Jaenicke, Christian Meesters, Dorothea Nillius, Heinz Decker, Jacqueline Nairn*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

69 Citations (Scopus)

Abstract

The enzymatic activity of phenoloxidase is assayed routinely in the presence of SDS. Similar assay conditions elicit phenoloxidase activity in another type 3 copper protein, namely hemocyanin, which normally functions as an oxygen carrier. The nature of the conformational changes induced in type 3 copper proteins by the denaturant SDS is unknown. This comparative study demonstrates that arthropod hemocyanins can be converted from being an oxygen carrier to a form which exhibits phenoloxidase activity by incubation with SDS, with accompanying changes in secondary and tertiary structure. Structural characterisation, using various biophysical methods, suggests that the micellar form of SDS is required to induce optimal conformational transitions in the protein which may result in opening a channel to the di-copper centre allowing bulky phenolic substrates access to the catalytic site. (c) 2007 Elsevier B.V. All rights reserved.

Original languageEnglish
Pages (from-to)1380-1394
Number of pages15
JournalBiochimica et Biophysica Acta - Proteins and Proteomics
Volume1774
Issue number11
DOIs
Publication statusPublished - Nov 2007

Keywords

  • hemocyanin
  • phenoloxidase
  • spectroscopy
  • enzyme activation
  • isothermal titration calorimetry
  • X-RAY-SCATTERING
  • EURYPELMA-CALIFORNICUM
  • PHENOLOXIDASE ACTIVITY
  • ARTHROPOD HEMOCYANIN
  • TARANTULA HEMOCYANIN
  • LIMULUS-POLYPHEMUS
  • CANCER-MAGISTER
  • DROSOPHILA-MELANOGASTER
  • ALLOSTERIC INTERACTIONS
  • LOBSTER HEMOCYANIN

Fingerprint

Dive into the research topics of 'Hemocyanin conformational changes associated with SDS-induced phenol oxidase activation'. Together they form a unique fingerprint.

Cite this