title: Immunoelectron microscopic double labeling of alkaline phosphatase and penicillinase with colloidal gold in frozen thin sections of Bacillus licheniformis 749/C.
abstract: The subcellular distribution of alkaline phosphatase and penicillinase was determined by double labeling frozen thin sections of Bacillus licheniformis 749/C with colloidal gold-immunoglobulin G (IgG). Antipenicillinase and anti-alkaline phosphatase antibodies were used to prepare complexes with 5- and 15-nm colloidal gold particles, respectively. The character of the labeling of membrane-bound alkaline phosphatase and penicillinase was different: the immunolabels for alkaline phosphatase (15-nm particles) were bound to a few sites at the inner surface of the plasma membrane, and the gold particles formed clusters of various sizes at the binding sites; the immunolabels for penicillinase (5-nm particles), on the other hand, were bound to the plasma membrane in a dispersed and random fashion. In the cytoplasm, immunolabels for both proteins were distributed randomly, and the character of their binding was similar. The labeling was specific: pretreating the frozen thin sections with different concentrations of anti-alkaline phosphatase or penicillinase blocked the binding of the immunolabel prepared with the same antibody. Binding could be fully blocked by pretreatment with 800 micrograms of either antibody per ml.
mesh_terms: D000469:Alkaline Phosphatase / Q000032:analysis* / Q000276:immunology; D001407:Bacillus / Q000201:enzymology* / Q000648:ultrastructure; D003102:Colloids; D005629:Frozen Sections; D006046:Gold; D006651:Histocytochemistry; D007074:Immunoglobulin G / Q000276:immunology; D008854:Microscopy, Electron; D010405:Penicillinase / Q000032:analysis* / Q000276:immunology
chemical_list: D003102:Colloids; D007074:Immunoglobulin G; D006046:Gold; D000469:Alkaline Phosphatase; D010405:Penicillinase