Ultrastructural alterations in Tetrahymena pyriformis induced by growth on saturated phospholipids at 40.1 degrees C

Structural changes in Tetrahymena pyriformis, strain WH-14, induced by growth on saturated phospholipids at 40.1 degrees C, uere studied by electron microscopy. Alterations in the ultrastructural organizations of the cell membrane and surface regions were common. These alterations were characterized in the displacement of kinetosomes, the spatial disorientation and disorganization of cortical ridges and grooves, and the spatial disorientation of longitudal and transverse microtubular ribbons. Irregular surface protrusions and multiple invaginations of alveolar membranes were among the most common features encountered. Disorganization of longitudinal microtubular ribbons was also a frequent encounter. The integrity of the ultrastructure of cell surface membranes and of the internal organization and ultrastructure of the kinetosomes, however, appeared to be unaltered. Other alterations included those of a number of cytoplasmic organelles (e.g. mitochondria and endoplasmic reticulum), which showed characteristic changes in the structural patterns.