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What do colony patterns mean? - A biologist’s view James A. Shapiro, University of Chicago 1. The colony as an organized, differentiated structure with a complex morphogenesis, even laboratory E. coli. 2. Patterns that reflect the formation of adaptive structures: genetic analysis. 3. A pattern that reflects the operation of adaptive systems under defined conditions: environmental analysis and modeling (Proteus mirabilis). 4. The dense-branching morphology of B. subtilis colonies under nutritional restriction: a problem for modeling.
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Clonal and Non-clonal Patterns in E. coli Colonies
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Initiation of E. coli colony development
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Morphogenesis and cellular differentiation in E. coli
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Colony differentiation into organized regions: E. coli
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Patterns that reflect the formation of adaptive structures: E. coli Budrene EO, Berg HC. Dynamics of formation of symmetrical patterns by chemotactic bacteria. Nature. 1995 376(6535):49- 53.
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Patterns that reflect the formation of adaptive structures: B. subtilis Fruiting Body Formation by Bacillus subtilis Steven S. Branda 1†, José Eduardo González-Pastor 2†, Sigal Ben-Yehuda 2, Richard Losick 2 and Roberto Kolter. Proc. Nat. Acad. Sci. USA, 98: 11621-11626
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Patterns that reflect the formation of adaptive structures: genetic analysis Esteban Lombardía, Adrián J. Rovetto, Ana L. Arabolaza, and Roberto R. Grau. A LuxS-Dependent Cell-to- Cell Language Regulates Social Behavior and Development in Bacillus subtilis. Journal of Bacteriology, June 2006, p. 4442-4452, Vol. 188
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A pattern that reflects the operation of adaptive systems under defined conditions: Proteus mirabilis. Where modeling matters most. Synchronous inoculationAsynchronous inoculation (1 hr)
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Proteus Crew L-R: Todd Dupont, Mitsugu Matsushita, Bruce Ayati, Oliver Rauprich, JAS, Sergei Esipov & Sune Danø
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Different cell types in Proteus swarming
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Distinct roles of glucose and amino acids in growth and swarming
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Dependence of swarming velocity on amino acid, not glucose concentration (above a threshold) Sune Danø
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Robust Periodicity in Proteus Swarming Rauprich O, Matsushita M, Weijer K, Siegert F, Esipov S, Shapiro JA. 1996. Periodic phenomena in Proteus mirabilis swarm colony development. J. Bacteriol. 178:6525-38
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Independence of swarm period from swarming velocity (amino acids) Sune Danø
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Interlocking Cell Cycles Esipov, S. and J.A.Shapiro. 1998. Kinetic model of Proteus mirabilis swarm colony development. J. Math. Biol. 36, 249-268.
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Kinetic Equations Esipov, S. and J.A.Shapiro. 1998. Kinetic model of Proteus mirabilis swarm colony development. J. Math. Biol. 36, 249-268. Diffusivity Spatially Resolved Kinetics Swarmer cell density
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Robust periodicity requires age- dependent dedifferentiation Bruce P. Ayati. Modeling the role of the cell cycle in regulating Proteus mirabilis swarm-colony development. Applied Mathematics Letters 20 (2007) 913–918
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Experimental examination of Proteus dedifferentiation A. Liew & JAS
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The dense-branching morphology of B. subtilis colonies under nutritional restriction: a problem ripe for modeling. Fujikawa H, and Matsushita M. 1989. Fractal growth of Bacillus subtilis on agar plates. J. Phys. Soc. Japan 58:3875-78
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Amino acid-dependent branching at different temperatures Julkowska DJulkowska D, Obuchowski M, Holland IB, Séror SJ. 2004. Branched swarming patterns on a synthetic medium formed by wild-type Bacillus subtilis strain 3610: detection of different cellular morphologies and constellations of cells as the complex architecture develops. Microbiology 150:1839-49.Obuchowski MHolland IBSéror SJ
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Motility occurs in a small “fingernail” region at the tip of each dendrite M. Matsushita
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Observations and hypotheses for modeling B. subtilis DBM Observations: 1.Amino acids necessary (I.B. Holland, personal communication) 2.DBM limited to a special region of the nutritional-mobility space 3.DBM characterized by branches that do not grow in width 4.Tip-splitting occurs when branches separated by a critical distance 5.Increased cell activity in a limited zone at the tip of each dendrite Hypotheses: 1.Tip expansion requires active cell movement inside front 2.Cell movement occurs only above a threshold amino acid level 3.Cell movement is the major sink for amino acid consumption 4.Glucose-based growth is not nutritionally limited
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