IMMUNOELECTRON MICROSCOPY OF HEMOCYANIN FROM THE KEYHOLE LIMPET (MEGATHURA-CRENULATA) - A PARALLEL SUBUNIT MODEL

Immunoelectron microscopy has been performed using negatively stained immune complexes of keyhole limpet hemocyanin (KLH) subunit 2 di- and multidecamers with domain-specific monoclonal antibodies. One antibody (KLH2a1) links the hemocyanin molecules in a side-to-side pattern, whereas the other antibody (KLH2fg1) links the molecules end-to-end. From existing knowledge of the domain sequence of KLH subunit 2, these data provide support for a parallel arrangement of subunits within each decamer. Ten N-terminal a domains are then present at the noncollar region of each decamer with 10 C- terminal g domains at the collar region. The immuno-negative staining data and the parallel KLH subunit model are discussed in relation to other models of molluscan hemocyanins from different species. © 1994 Academic Press. All rights reserved.