Electron microscopic localization of concanavalin A receptor sites in pollen surface material after fixation with glutaraldehyde-cetylpyridinium chloride.
Pollen from birch trees (Betula pendula) was fixed in glutaraldehyde containing 0.5% cetylpyridinium chloride (CPC), incubated with concanavalin A (Con A)-ferritin, postfixed in osmium, dehydrated, and embedded in Epon. On ultrathin sections, ferritin particles were observed closely associated with the electron-dense material precipitated by CPC on the surface of the pollen grains. Controls for CPC, which were fixed in glutaraldehyde alone, showed no electron-dense material on the surface. In controls for Con A, which were incubated in Con A-ferritin in the presence of the inhibitory sugar (alpha-methyl-D-mannopyranoside), no ferritin particles were observed. The above-described procedure thus allows the localization of sugar residues in highly soluble pollen wall glycoproteins.
D002594:Cetylpyridinium; D005404:Fixatives; D005976:Glutaral; D008854:Microscopy, Electron; D011058:Pollen / Q000032:analysis* / Q000648:ultrastructure; D011952:Receptors, Concanavalin A / Q000032:analysis*
D005404:Fixatives; D011952:Receptors, Concanavalin A; D002594:Cetylpyridinium; D005976:Glutaral