MESOMAS: function and characteristics

Prokaryotic cells do not have a cell nucleus that protects genetic material as it does in eukaryotic cells. Instead, the genetic material of prokaryotic cells It is found scattered throughout its cytoplasm, but it is not completely disorganized, but at certain points it is associated with the plasma membrane in the so-called mesosomes. In this lesson from a TEACHER we talk about mesosomes: function and characteristics. If you are interested in learning more about them, join us below!

Mesosomes were first observed in 1953 by chemists George B. Chapman and James Hillier, that they called them as peripheral organs, and it was not until 1959 when J.D. Robertson named him mesosomes. At this time, enough was known about the internal structure of the prokaryotic cell and the electron microscope was already in use. Since the field of cytology was also quite advanced, the discovery of these new structures was revolutionary.

Once these new structures were discovered, hypotheses about their functions began to be devised. They said that their function was to form the wall that separates the daughter cells after division, or that oxidative phosphorylation took place in this area, a function similar to that of eukaryotic mitochondria.

However, although the mesosomes had been observed by scientists, with the evolution of new techniques of preparing the structures for their observation with the microscope, these structures stopped appearing, with which it was concluded that the observation of these were due to membrane damage during sample preparation in the early days of the microscope, that is, they were technical errors.

Many researchers of the time refuted the theory that they were malformations in all situations, presenting evidence that was often discarded. Finally, these structures they were accepted by the entire scientific community.

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In the prokaryotic cells there are some membranous folds from the plasma membrane into the cytoplasm and found in most bacteria. These are not useless areas for the cell, but rather they harbor important enzymes that act in metabolic processes important of the prokaryotic cell and occurring mostly in its membrane.

These folds into the cell interior have a spiral shape and constitute invaginations that are the origin of mesosomes. Mesosomes are very important in metabolic functions of the cell, they are composed of lipids and proteins and act in the beginning of the division of the cells and in the distribution of the genetic material in a balanced way between the two daughter cells

Mesosomes are located in an area that would be equivalent to the loop area in the eukaryotic cells and close to the place of cell division. Although mesosomes are not found in eukaryotic cells, they possess functions similar to those of eukaryotic mitochondria, as can be the breath.

Mesosomes possess enzymes for many metabolic processes in the cell, such as duplication and transcription of prokaryotic DNA, reactions in respiration, photosynthesis, glycolysis, or the synthesis of membrane materials.

Regarding the shape of mesosomes, it is about extensions in the form of an open roll, which do not have compartments and accumulate respiratory corpuscles attached to their membrane, variable in size and number.

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