Flagella and pili are both necessary for efficient attachment of Methanococcus maripaludis to surfaces

Area of Science:

• Microbiology
• Cell Biology
• Biophysics

Background:

• Methanococcus maripaludis possesses flagella for motility and pili, whose function remains unassigned.
• Previous research established flagella's role in swimming but not in surface interactions.

Purpose of the Study:

• To investigate the role of flagella and pili in the surface attachment of Methanococcus maripaludis.
• To compare wild-type cells with mutants lacking flagella, pili, or both.

Main Methods:

• Scanning electron microscopy was used to observe wild-type and mutant M. maripaludis cells.
• Attachment assays were performed on various surfaces including nickel, gold, molybdenum, glass, silicon, and mica.

Main Results:

• Wild-type M. maripaludis cells exhibited attachment to most surfaces via flagella, forming large cables that connected cells.
• Mutant cells lacking flagella, pili, or both demonstrated significantly impaired surface attachment.
• Flagella were observed to unwind on surfaces, suggesting a mechanical role in adhesion.

Conclusions:

• Flagella have a dual role in M. maripaludis: swimming and surface attachment.
• Pili are essential for surface attachment in M. maripaludis, representing their first identified function.
• Both flagella and pili are critical for efficient cell adhesion to diverse substrates.