Chapter 9 : Cultivation of Microbial Consortia and Communities

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Model systems may be used for cultivation of microbial communities, and they offer the advantages of relative simplicity, experimental control, and replication. Some of the criteria used for isolating communities, and other types of cultures, are discussed in this chapter. Cultivation of defined communities requires that community culture methods be used instead of enrichment culture to better define the environment in terms of the concentration and flux of both substrates and products. The chapter emphasizes those culture systems which provide adequate environmental control of substrate flux and concentration throughout the time course of cultivation. Although batch systems may be used to cultivate microbial associations, they should be used and interpreted with caution. Chemostats, nutristats, microstats, and continuous-flow slide cultures (CFSCs) are among the culture methods commonly used to cultivate consortia and communities. Chemostats and other continuous cultures are among the most widely used systems for cultivating microbial communities and microbial consortia. Robbins device is one of the best-known and most widely used systems for studying biofilm communities and pure culture biofilms in applications ranging from medical to industrial and food research. Microstats are used for the cultivation of biofilm communities, as opposed to planktonic communities. Storage of communities under conditions suitable for preserving pure cultures may be inadequate for the preservation of communities.

Citation: Wolfaardt G, Korber D, Lawrence J. 2007. Cultivation of Microbial Consortia and Communities, p 101-111. In Hurst C, Crawford R, Garland J, Lipson D, Mills A, Stetzenbach L (ed), Manual of Environmental Microbiology, Third Edition. ASM Press, Washington, DC. doi: 10.1128/9781555815882.ch9
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Image of FIGURE 1

Photographs of a RAB setup, showing general arrangement of multiple reactors and plumbing (A) and details of the inner rotating cylinder with 12 removable polycarbonate strips for biofilm development and subsequent analyses (B).

Citation: Wolfaardt G, Korber D, Lawrence J. 2007. Cultivation of Microbial Consortia and Communities, p 101-111. In Hurst C, Crawford R, Garland J, Lipson D, Mills A, Stetzenbach L (ed), Manual of Environmental Microbiology, Third Edition. ASM Press, Washington, DC. doi: 10.1128/9781555815882.ch9
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Image of FIGURE 2

Schematic diagram of a multichannel flow cell. The use of flow cells containing multiple channels simplifies multiple comparisons, replication, and controls.

Citation: Wolfaardt G, Korber D, Lawrence J. 2007. Cultivation of Microbial Consortia and Communities, p 101-111. In Hurst C, Crawford R, Garland J, Lipson D, Mills A, Stetzenbach L (ed), Manual of Environmental Microbiology, Third Edition. ASM Press, Washington, DC. doi: 10.1128/9781555815882.ch9
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Image of FIGURE 3

(Left) Schematic cross section of a microstat perpendicular to the concentration gradient that develops through the porous matrix. The flow over the surface against the direction of the concentration gradient removes molecules as they diffuse out of the porous medium, thereby maintaining a steady state. Adapted from reference . (Right) Photograph of a microstat showing two-dimensional steady-state diffusion gradients that were created by diffusion through an agarose gel. In the case of recalcitrant compounds, microbial communities are provided spatial and temporal gradients on the surface of the gel, thereby allowing organization of community composition and biofilm structure that may facilitate improved utilization of the substrate.

Citation: Wolfaardt G, Korber D, Lawrence J. 2007. Cultivation of Microbial Consortia and Communities, p 101-111. In Hurst C, Crawford R, Garland J, Lipson D, Mills A, Stetzenbach L (ed), Manual of Environmental Microbiology, Third Edition. ASM Press, Washington, DC. doi: 10.1128/9781555815882.ch9
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