Topology of the 10 subunits within the decamer of KLH, the hemocyanin of the marine gastropod Megathura crenulata

J Struct Biol. 2002 Sep;139(3):153-9. doi: 10.1016/s1047-8477(02)00591-9.

Abstract

Immunoelectron microscopy has been performed using negatively stained immune complexes of keyhole limpet hemocyanin isoform 1 (KLH1) decamers and a functional unit-specific monoclonal antibody anti-KLH1-c1. The antibody links hemocyanin molecules at both the collar and the collarless edge of the decamer, indicating a peripheral localization of functional units c. In isoform 2 (KLH2) the positions of functional units c have been identified with the peanut agglutinin (PNA), which has previously been shown to exclusively bind to KLH2-c. Ferritin linked to PNA was used to visualize labeled molecules electron microscopically. The pattern of labeling also indicates a peripheral localization of the c functional units. The data presented in this paper support only one of two possible models for the subunit orientation within the hemocyanin decamer.

MeSH terms

  • Animals
  • Crystallography, X-Ray
  • Hemocyanins / chemistry*
  • Hemocyanins / isolation & purification
  • Hemocyanins / ultrastructure
  • Microscopy, Electron
  • Models, Molecular
  • Molecular Weight
  • Mollusca / chemistry*
  • Protein Structure, Quaternary
  • Protein Subunits / chemistry*
  • Protein Subunits / isolation & purification

Substances

  • Protein Subunits
  • Hemocyanins
  • keyhole-limpet hemocyanin