Mycoplasma like Organisms Or Pleuro Pneumonia like Organisms (PPLO)
Mycoplasmas are the smallest, walless, free living microorganisms, cause disease similar to virus in plants. Doi ct.al. (1967) described the structure of this pathogen using election microscope. Mycoplasmas like bodies have also been detected in electron micro graphs of plants suffering from corn. Stunt and aster yellow.
“Mycoplasma are smallest, free living, walless, prokaryotic organism without an organised and bounded nucleus.”
Mycoplasma lack rigid cell wall, being surrounded only by single tripla layered unit membrane which allows them to be highly plemorphic. They assume vast array of shapes and size. They require sterols (Lipoproteins) for growth Mycoplasma cannot be grown on artificial media and they reproduce by budding and binary fissions.
Mycoplasma like organisms are included in class: Mollicutes which has one order: Mycoplasmatales. The order has three families, each family containing one genus.
1. Mycoplasmataceae: One genus Mycoplasma.
2. Acholeplamataceae: One genus Acholeoplasma.
3. Spiroplasmataceae: One genus Spiroplasma.
These genera are separated on the basis of their sterol requirement for growth.