Tip extension and simultaneous multiple fission in a filamentous bacterium

Area of Science:

• Microbiology
• Bacterial Morphology
• Biofilm Development

Background:

• Bacterial cell shape and growth are crucial for microbial community structure.
• The filamentous bacterium Corynebacterium matruchotii forms core structures in dental plaque biofilms.
• The developmental processes of C. matruchotii filaments are not well understood.

Purpose of the Study:

• To investigate the cell cycle and division mechanisms of Corynebacterium matruchotii.
• To elucidate the growth strategy and filament formation in dental plaque biofilms.
• To understand how C. matruchotii establishes its spatial organization within microbial consortia.

Main Methods:

• Live-cell time-lapse microscopy was employed to observe bacterial growth dynamics.
• Fluorescent D-amino acids were used to track peptidoglycan biosynthesis and cell wall formation.
• Comparative analysis with related bacterial species was performed.

Main Results:

• Corynebacterium matruchotii exhibits tip extension growth, similar to Streptomyces.
• Filaments elongate at rates significantly faster than related species.
• Simultaneous multiple septation occurs, resulting in 3 to 14 daughter cells per filament.
• Daughter cells initiate new filaments, forming the characteristic 'whip handle' morphology.

Conclusions:

• This study reveals an unprecedented mode of multiple simultaneous division in bacteria.
• The unique growth and division strategy of C. matruchotii contributes to its success in dental plaque.
• Findings expand the understanding of bacterial cell cycle diversity and adaptation.