The Growth of Bacterial Colonies

Cooperative formation of chiral patterns during growth of bacterial colonies.

Orientation field model for chiral branching growth of bacterial colonies

We present a new reaction-diffusion model for chiral branching growth of colonies of the bacteria Paenibacillus dendritiformis. In our model the bacteria are represented by a density field with nonlinear diffusion and a complex scalar field which represents bacterial orientation. The orientation field introduces anisotropy into the flux of bacteria, representing self-propulsion along their long...

Lubricating bacteria model for branching growth of bacterial colonies.

Various bacterial strains (e.g., strains belonging to the genera Bacillus, Paenibacillus, Serratia, and Salmonella) exhibit colonial branching patterns during growth on poor semisolid substrates. These patterns reflect the bacterial cooperative self-organization. A central part of the cooperation is the collective formation of a lubricant on top of the agar which enables the bacteria to swim. H...

Universality in Bacterial Colonies

The emergent spatial patterns generated by growing bacterial colonies have been the focus of intense study in physics during the last twenty years. Both experimental and theoretical investigations have made possible a clear qualitative picture of the different structures that such colonies can exhibit, depending on the medium on which they are growing. However, there are relatively few quantita...

Counting Bacterial Colonies

MALLIGO, JOHN E. (Fort Detrick, Frederick, Md.). Evaluation of an automatic electronic device for counting bacterial colonies. Appl. Microbiol. 13:931-934. 1965.-An automatic colony counter was tested extensively with colonies of two bacterial species, Serratia marcescens and Bacillus subtilis var. niger, grown on agar media. A stable relationship was established between machine counts and coun...