Abstract: Compositions, methods and kits are provided. The compositions, methods and kits are for assembly of series of DNA segments in yeast using homologous recombination. The assembled DNA segments are maintained episomally. Yeast made using the methods are included, as are methods of using the yeast to express proteins, and for screening test agents that can affect yeast that are modified to include the assembled DNA segments.

Abstract: Provided are modified microorganisms which are modified such that their growth can be controlled using exogenously provided compounds. The microorganisms can be modified by genetic alterations that include a promoter inducible by a first exogenously supplied compound. The promoter can be configured to drive expression of an RNA coding sequence that may be essential to growth of the microorganism. The microorganisms may also be modified to include site specific recombinase recognition sites flanking or within the RNA coding sequence so that expression of the corresponding site specific recombinase will disrupt transcription of the RNA. The site specific recombinase can be configured such that it expression and/or activity is suppressed by a second exogenously supplied compound. Methods of making the modified microorganisms and kits that contain reagents for making and using the modified microorganisms are also provided.

Abstract: Provided are modified microorganisms which are modified such that their growth can be controlled using exogenously provided compounds. The microorganisms can be modified by genetic alterations that include a promoter inducible by a first exogenously supplied compound. The promoter can be configured to drive expression of an RNA coding sequence that may be essential to growth of the microorganism. The microorganisms may also be modified to include site specific recombinase recognition sites flanking or within the RNA coding sequence so that expression of the corresponding site specific recombinase will disrupt transcription of the RNA. The site specific recombinase can be configured such that it expression and/or activity is suppressed by a second exogenously supplied compound. Methods of making the modified microorganisms and kits that contain reagents for making and using the modified microorganisms are also provided.

Abstract: Compositions, methods and kits are provided. The compositions, methods and kits are for assembly of series of DNA segments in yeast using homologous recombination. The assembled DNA segments are maintained episomally. Yeast made using the methods are included, as are methods of using the yeast to express proteins, and for screening test agents that can affect yeast that are modified to include the assembled DNA segments.

Abstract: Provided are modified microorganisms which are modified such that their growth can be controlled using exogenously provided compounds. The microorganisms can be modified by genetic alterations that include a promoter inducible by a first exogenously supplied compound. The promoter can be configured to drive expression of an RNA coding sequence that may be essential to growth of the microorganism. The microorganisms may also be modified to include site specific recombinase recognition sites flanking or within the RNA coding sequence so that expression of the corresponding site specific recombinase will disrupt transcription of the RNA. The site specific recombinase can be configured such that it expression and/or activity is suppressed by a second exogenously supplied compound. Methods of making the modified microorganisms and kits that contain reagents for making and using the modified microorganisms are also provided.

Abstract: Provided are compositions and methods for use in assembling and expressing a plurality of transcription units using, in one aspect, homologous recombination in yeast. Yeast containing the plurality of transcription units, and isolated transcription units, are also provided. Kits for use in making the yeast and the transcript units are further included.

Abstract: Provided are compositions and methods for use in assembling and expressing a plurality of transcription units using, in one aspect, homologous recombination in yeast. Yeast containing the plurality of transcription units, and isolated transcription units, are also provided. Kits for use in making the yeast and the transcript units are further included.

Abstract: Provided are compositions and methods for use in assembling and expressing a plurality of transcription units using, in one aspect, homologous recombination in yeast. Yeast containing the plurality of transcription units, and isolated transcription units, are also provided. Kits for use in making the yeast and the transcript units are further included.

Abstract: Provided are modified microorganisms which are modified such that their growth can be controlled using exogenously provided compounds. The microorganisms can be modified by genetic alterations that include a promoter inducible by a first exogenously supplied compound. The promoter can be configured to drive expression of an RNA coding sequence that may be essential to growth of the microorganism. The microorganisms may also be modified to include site specific recombinase recognition sites flanking or within the RNA coding sequence so that expression of the corresponding site specific recombinase will disrupt transcription of the RNA. The site specific recombinase can be configured such that it expression and/or activity is suppressed by a second exogenously supplied compound. Methods of making the modified microorganisms and kits that contain reagents for making and using the modified microorganisms are also provided.

Abstract: Provided are compositions and methods for use in assembling and expressing a plurality of transcription units using, in one aspect, homologous recombination in yeast. Yeast containing the plurality of transcription units, and isolated transcription units, are also provided. Kits for use in making the yeast and the transcript units are further included.