Mollicutes-wall-less bacteria with internal cytoskeletons

Area of Science:

• Microbiology
• Cell Biology
• Biophysics

Background:

• Mollicutes are wall-less eubacteria, representing minimal cells evolved from Clostridia.
• They possess unique structural features, including an internal cytoskeleton, distinguishing them from other bacteria.
• Understanding their structure is key to understanding basic cellular mechanisms.

Purpose of the Study:

• To review the structure and motility of Mollicutes (Spiroplasma, Mycoplasma, Acholeplasma).
• To analyze Mollicute motility and structural dynamics from the perspective of prokaryotic and eukaryotic motors.
• To model Spiroplasma motility using its unique cytoskeleton.

Main Methods:

• Structural and geometrical analysis of Spiroplasma.
• Comparative review of prokaryotic and eukaryotic motor systems.
• Modeling of cell motility based on cytoskeletal function.

Main Results:

• Mollicutes are characterized by a complete lack of cell walls and the presence of an internal cytoskeleton.
• Spiroplasma possess a flat, ribbon-like cytoskeleton within helical cells.
• The cytoskeleton acts as a linear motor, explaining Spiroplasma motility and shape changes.

Conclusions:

• The cytoskeleton is central to Mollicute structure and motility.
• Spiroplasma's motility can be mechanistically explained by its cytoskeleton acting as a linear motor.
• This provides insights into the evolution of minimal cells and biological motors.