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Selections from Screens: a Novel Tool for the Selection of Overproducers

Michael D. Lynch, University of Colorado, ECCH 111, Campus Box 424, Boulder, CO 80309, Tirzah Ya'el Mills, Chemical Engineering, West Virginia University, 956 Ashton Place, Morgantown, WV 26508, and Ryan T. Gill, Department of Chemical and Biological Engineering, University of Colorado, Campus Box 424, Boulder, CO 80309.

The combination of newly developed population based genomics tools and selection strategies have recently made the mapping of fitness to genotype a high throughput endeavor. However, when these tools are applied to non-selectable phenotypes, such as metabolite or organic acid production, they still require an enormous amount of screening. Screening populations with greater than 107 members becomes prohibitive and as in all screening strategies is a severe limitation when compared to selection. We have recently developed a new genomics tool to rapidly select for promoters responsive to specific environmental conditions such as product concentration. Linking these promoters to selectable reporters such as antibiotic resistance markers allows us to link the production to survival and select for a previously non-selectable phenotype. This advance allows for the application of population based genomics tools to map non-selectable phenotypes to genotypes and for more rapid strain engineering.