A CELLULAR AUTOMATA MODEL FOR BIOFILM GROWTH

A CELLULAR AUTOMATA MODEL FOR BIOFILM GROWTH

Rodriguez, D.; Carpio, A.; Einarsson, B.

Full Article:

Biofilms are aggregates of bacteria attached to surfaces, which are very adaptable to changes in the environment and survive under extreme conditions. These living structures are behind many problems in research and industry. Therefore there is an increasing interest in improving our understanding on biofilms to be able to control them, either designing protocols to destroy them when harmful or promoting their growth when beneficial. A bidimensional cellular automata model for biofilm development is proposed to study the biofilm behaviour as its key growth parameters vary. The model includes several metabolic and spreading mechanisms typical of bacteria: cell division and spreading, detachment mechanisms adapted to the flow and probabilistic rules for EPS matrix generation. Numerical simulations of the model reproduce a number of biofilm patterns observed in real experiments: ripples, streamers, mushroom networks and patches. The influence of the nutrient concentration and the type of flow on the evolution of the bacterial community is monitorized. Biofilm tends to cover the whole surface when enough nutrients are available. Erosion enhances the creation of holes in this cover and promotes a variety of geometric patterns. The survival of the colony and its final shape will depend on the balance between the main growth parameters. Large Reynolds numbers and poor nutrient sources promote the formation of flat, and thin biofilms. Decreasing the Reynolds number or increasing the nutrient and oxygen concentration enhance pattern formation.

Biofilms are aggregates of bacteria attached to surfaces, which are very adaptable to changes in the environment and survive under extreme conditions. These living structures are behind many problems in research and industry. Therefore there is an increasing interest in improving our understanding on biofilms to be able to control them, either designing protocols to destroy them when harmful or promoting their growth when beneficial. A bidimensional cellular automata model for biofilm development is proposed to study the biofilm behaviour as its key growth parameters vary. The model includes several metabolic and spreading mechanisms typical of bacteria: cell division and spreading, detachment mechanisms adapted to the flow and probabilistic rules for EPS matrix generation. Numerical simulations of the model reproduce a number of biofilm patterns observed in real experiments: ripples, streamers, mushroom networks and patches. The influence of the nutrient concentration and the type of flow on the evolution of the bacterial community is monitorized. Biofilm tends to cover the whole surface when enough nutrients are available. Erosion enhances the creation of holes in this cover and promotes a variety of geometric patterns. The survival of the colony and its final shape will depend on the balance between the main growth parameters. Large Reynolds numbers and poor nutrient sources promote the formation of flat, and thin biofilms. Decreasing the Reynolds number or increasing the nutrient and oxygen concentration enhance pattern formation.

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DOI: 10.5151/meceng-wccm2012-16793

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Como citar:

Rodriguez, D.; Carpio, A.; Einarsson, B.; "A CELLULAR AUTOMATA MODEL FOR BIOFILM GROWTH", p-409-421. In: In Proceedings of the 10th World Congress on Computational Mechanics [= Blucher Mechanical Engineering Proceedings, v. 1, n. 1]. São Paulo: Blucher, 2014.
ISSN 23580828, DOI 10.5151/meceng-wccm2012-16793