Three-dimensional immunoelectron microscopy of scorpion hemocyanin labeled with a monoclonal Fab fragment.
An immunocomplex of the 4 x 6-meric hemocyanin of the scorpion Androctonus australis with the monoclonal Fab fragment L104 was reconstructed from electron micrographs of a negatively stained specimen, using the double-carbon-layer technique. The resulting structure enables a clear visualization of the Fab fragments bound to the four copies of the Aa6 subunit and directly confirms a previous localization of the L104 epitope deduced from two-dimensional image processing. Despite a strong flattening effect produced by the negative-staining technique the orientations of the Fab fragments are well characterized. Moreover, the observation of a central hole within the elbow bends of the Fab fragments provides information about the disposition of the Fabs around their main axis.
Boisset
N
N
Laboratoire de Biochimie Fondamentale, Tours, France.
Radermacher
M
M
Grassucci
R
R
Taveau
J C
JC
Liu
W
W
Lamy
J
J
Frank
J
J
Lamy
J N
JN
D000818:Animals; D000911:Antibodies, Monoclonal; D006433:Hemocyanins / Q000737:chemistry / Q000276:immunology / Q000648:ultrastructure*; D007091:Image Processing, Computer-Assisted; D007140:Immunoglobulin Fab Fragments; D016253:Microscopy, Immunoelectron; D008958:Models, Molecular; D012605:Scorpions
D000911:Antibodies, Monoclonal; D007140:Immunoglobulin Fab Fragments; D006433:Hemocyanins