views updated

Spiroplasma (family Spiroplasmataceae, order Mycoplasmatales) A genus of bacteria in which the cells are somewhat variable in shape, but all can form helical filaments; the cells lack cell walls. They are motile by an unknown mechanism; there are no flagella. They are chemo-organotrophic, and can grow in the presence or absence of air. They are epiphytic (see EPIPHYTE) or parasitic in plants and arthropods, and can cause disease (e.g. stubborn disease of citrus trees).