This project is designed to develop methods for precombustion coal remediation by implementing recent advances in enzyme biochemistry. The novel approach of this study is incorporation of hydrophilic oxidative enzymes in reverse micelles in an organic solvent. Enzymes from commercial sources or microbial extracts are being investigated for their capacity to remove organic sulfur from coal by oxidation of the sulfur groups, splitting of C-S bonds and loss of sulfur as sulfuric acid. Dibenzothiophene (DBT) and ethylphenylsulfide (EPS) are serving as models of organic sulfur-containing components of coal in initial studies. A goal of this project is to define a reverse micelle system that optimizes the catalytic activity of enzymes toward desulfurization of model compounds and ultimately coal samples. Studies by several groups (Martinek et al., 1981; Kabanov et al., 1988; Martinek, 1989; Verhaert et al., 1990) have shown that the surfactant AOT over a broad concentration range in organic solvents produces micelles, comparatively uniform in diameter, which incorporate hydrophilic enzymes. The activity (kcat) of certain enzymes in this system is higher than in aqueous solution. This surfactant is therefore being examined as a vehicle for enhancement of sulfoxidation reactions.

This project is designed to develop methods for precombustion coal remediation by implementing recent advances in enzyme biochemistry. The novel approach of this study is incorporation of hydrophilic oxidative enzymes in reverse micelles in an organic solvent. Enzymes from commercial sources or microbial extracts are being investigated for their capacity to remove organic sulfur from coal by oxidation of the sulfur groups, splitting of C-S bonds and loss of sulfur as sulfuric acid. Dibenzothiophene (DBT) and ethylphenylsulfide (EPS) are serving as models of organic sulfur-containing components of coal in initial studies. A goal of this project is to define a reverse micelle system that optimizes the catalytic activity of enzymes toward desulfurization of model compounds and ultimately coal samples. Studies by several groups (Martinek et al., 1981; Kabanov et al., 1988; Martinek, 1989; Verhaert et al., 1990) have shown that the surfactant AOT over a broad concentration range in organic solvents produces micelles, comparatively uniform in diameter, which incorporate hydrophilic enzymes. The activity (kcat) of certain enzymes in this system is higher than in aqueous solution. This surfactant is therefore being examined as a vehicle for enhancement of sulfoxidation reactions.

The immediate objective of this project is to characterize and purify the enzymes involved in degrading organic sulfur in coal from two well characterization organic sulfur degrading strains, of Rhodococces rhodochorous IGTS8 and K3B. We believe that characterization and purification of these enzymes may provide valuable information that will lead to developing or isolating better strains for desulfurization of coal. Our recent results imply that the IGTS8 enzymes are firmly attached to the cell wall. For coal desulfurization it is better to have a microorganism that can secrete its desulfurization enzymes into the medium. The enzymes could permeate into coal much better than a bacterial cell. We seek that the isolation of a mutant of IGTS8 which can release the desulfurization enzymes in the cultural medium. During this period, we carried out more electron microscope analysis of IGTS8 and related species. These strains grow very poorly in DBT medium as well as in medium containing high sulfate concentration. Cells used for EM analysis were cultured in rich medium with glucose but found that there is no protruding structures on the cells of R. rhodochorous 184 and 13808. We believe that we should also examine the 183 and 13808 cells that …

The immediate objective of this project is to characterize and purify the enzymes involved in degrading organic sulfur in coal from two well characterization organic sulfur degrading strains, of Rhodococces rhodochorous IGTS8 and K3B. We believe that characterization and purification of these enzymes may provide valuable information that will lead to developing or isolating better strains for desulfurization of coal. Our recent results imply that the IGTS8 enzymes are firmly attached to the cell wall. For coal desulfurization it is better to have a microorganism that can secrete its desulfurization enzymes into the medium. The enzymes could permeate into coal much better than a bacterial cell. We seek that the isolation of a mutant of IGTS8 which can release the desulfurization enzymes in the cultural medium. During this period, we carried out more electron microscope analysis of IGTS8 and related species. These strains grow very poorly in DBT medium as well as in medium containing high sulfate concentration. Cells used for EM analysis were cultured in rich medium with glucose but found that there is no protruding structures on the cells of R. rhodochorous 184 and 13808. We believe that we should also examine the 183 and 13808 cells that …

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