Mycoplasma-short notes

General Characteristics :


Mycoplasma is a form of bacteria which was stidied by Nocard and Roux in 1998.

Nowork named ita s Mycoplasma like organism. These are also called as Pleuropneumonia like organisms.

Mycoplasma lacks celk wall and so have no shape i.e. pleomorphic in nature. Hence they are called as ''Jokers in the microbiological pack''.

They were first isolated from Bovine sheep suffering from pleuropneumonia.

The human infertility and abortions are now known to be due to mycoplasma infections in the urinogenetical tract. Many plant diseases eg., Aster yellow, Potato witches broom and Dwarg disease of mulberry are due to mycoplasma.

In 1966, International Committee of Nomenclature of Bacteria, recognised Mycoplasma, as different form of bacteria and placed them under a seperate class-Molicutes which consists of two genera-Mycoplasma and Acholeplasm.


It has no cell wall, A three layered Plasma membrane is present as outer covering.

These are unicellular, non-motile and prokaryotic organisms. These are parasitic and also saprophytic.

These are gram -ve(negetive) organisms, Ribosomes are mostly 72s type. Plant mycoplasma are present in the sap of phloem tissue.

They pass through bacteria-proof filters so these are the smallest free-living gram negetive cells.

They require sterols for growth.

They are insensitive to pencillin. However, they may be killed by using Tetracycline and Chloramphenicol.

They can reproduce by Binary fission, by formation of Spores or by Budding.

Genetic material is dsDNA and RNA is present in the non-aqueous substance of the cell.

Symptoms are mild, rarely requires hospitalization.

Infections of the middle ear (otitis media) also can result.

At this time there are no vaccines and are noneffective measures for control. As with any respiratory diseases, allpeople should cover their face when coughing or sneezing.

In plants like brinjal and papaya it causes diseases by which the leaves of the respective plants get affected.


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