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Updated: Aug 15, 2026
10:59
Recording Multicellular Behavior in Myxococcus xanthus Biofilms using Time-lapse Microcinematography
Published on: August 6, 2010
RasA is required for Myxococcus xanthus development and social motility
Vinh D Pham1, Conrad W Shebelut, Bipasha Mukherjee
1Section of Microbiology, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.
Journal of Bacteriology
|September 17, 2005
Summary
A mutation in the rasA gene stopped Myxococcus xanthus development and reduced swarm expansion. RasA is essential for forming extracellular fibrils and social gliding motility.
Area of Science:
- Microbiology
- Molecular Biology
- Cell Biology
Background:
- Myxococcus xanthus exhibits complex multicellular behaviors, including developmental aggregation and sporulation.
- Social motility and extracellular fibril formation are crucial for M. xanthus development and survival.
Purpose of the Study:
- To investigate the role of the rasA gene in Myxococcus xanthus development, motility, and fibril formation.
Main Methods:
- Genetic analysis involving insertion mutagenesis in the rasA gene.
- Phenotypic characterization of mutant strains, including developmental assays (aggregation, sporulation) and motility assessments (swarm expansion, fibril formation).
Main Results:
- Insertion in the rasA gene completely inhibited developmental aggregation and sporulation.
- The rasA mutation significantly reduced swarm expansion on low-agar (0.3%) surfaces.
- Data indicate that rasA is necessary for the formation of extracellular fibrils.
- RasA is required for social gliding motility in M. xanthus.
Conclusions:
- The rasA gene plays a critical role in regulating Myxococcus xanthus multicellular development.
- RasA is essential for both extracellular fibril production and social gliding motility, processes vital for M. xanthus life cycle.
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