Abstract: Provided herein, is a means for development of ferrochelatase variants with improved tolerance towards N-methyl protoporphyrin. Also disclosed are cell assay systems utilizing the variants, as the variants would confer resistance to N-methyl protoporphyrin inhibition and thereby keep heme synthesis uninterrupted. The variants contain loop mutations that affect the NMPP-ferrochelatase interaction, and different degrees of NMPP tolerance are obtained with the introduction of loop mutations in wild-type ferrochelatase. Also disclosed is kinetic mechanism of inhibition of ferrochelatase by NMPP, using the disclosed variants whose mutations in the “porphyrin-interacting loop” motif weakened the potency of NMPP as an inhibitor.

Abstract: Described herein are methods, compositions and synthetic biology approaches for solvent production, including but not limited to butanol production. Described herein are recombinant bacteria and yeast strains which may be used in production of a solvent, including but not limited to butanol, from lignocellulosic and other plant-based feedstocks. Described herein are methods of producing solvents, including but not limited to butanol, using bacteria and yeast strains. Described herein are methods of producing organisms that display highly efficient butanol production.

Abstract: Provided herein, is a means for development of ferrochelatase variants with improved tolerance towards N-methyl protoporphyrin. Also disclosed are cell assay systems utilizing the variants, as the variants would confer resistance to N-methyl protoporphyrin inhibition and thereby keep heme synthesis uninterrupted. The variants contain loop mutations that affect the NMPP-ferrochelatase interaction, and different degrees of NMPP tolerance are obtained with the introduction of loop mutations in wild-type ferrochelatase. Also disclosed is kinetic mechanism of inhibition of ferrochelatase by NMPP, using the disclosed variants whose mutations in the “porphyrin-interacting loop” motif weakened the potency of NMPP as an inhibitor.

Abstract: Homostructured, cation exchanged, layered compositions containing mixed onium and alkali metal, alkaline earth metal, protonated hydronium ions and mixtures thereof are described. Particulate concentrates formed by intercalation of a polymer component into the galleries of the layered inorganic and organic homostructured layered cation exchange composition and to the use of the particulate concentrates for the preparation of cured polymer-inorganic nanolayer hybrid composite compositions are described. In the most preferred embodiment of the invention the layered inorganic composition is selected from the family of 2:1 layered silicate clays.

Abstract: Homostructured, cation exchanged, layered compositions containing mixed onium and alkali metal, alkaline earth metal, protonated hydronium ions and mixtures thereof are described. Particulate concentrates formed by intercalation of a polymer component into the galleries of the layered inorganic and organic homostructured layered cation exchange composition and to the use of the particulate concentrates for the preparation of cured polymer-inorganic nanolayer hybrid composite compositions are described. In the most preferred embodiment of the invention the layered inorganic composition is selected from the family of 2:1 layered silicate clays.