Patents by Inventor John D. Childs

John D. Childs has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6274372
    Abstract: The invention provides a novel flavin reductase, which has been isolated from Rhodococcus strain sp. IGTS8 and purified to homogeneity. The flavin reductase is of use in the biocatalytic desulfurization of a fossil fuel containing organic sulfur compounds. The method comprises the steps of (1) contacting the fossil fuel with an aqueous phase containing a biocatalyst capable of cleaving carbon—sulfur bonds and a rate-enhancing amount of the flavin reductase of the present invention, thereby forming a fossil fuel and aqueous phase mixture; (2) maintaining the mixture under conditions sufficient for cleavage of the carbon—sulfur bonds of the organic sulfur molecules by the biocatalyst, thereby resulting in a fossil fuel having a reduced organic sulfur content; and (3) separating the fossil fuel having a reduced organic sulfur content from the resulting aqueous phase.
    Type: Grant
    Filed: May 3, 1999
    Date of Patent: August 14, 2001
    Assignee: Enchira Biotechnology Corporation
    Inventors: Kevin A. Gray, John D. Childs, Charles H. Squires
  • Patent number: 6235519
    Abstract: The present invention relates to an isolated nucleic acid molecule which encodes one or more of the enzymes which catalyze one or more steps in the desulfurization of thiophene, or a homologue or active fragment thereof. The invention also includes a recombinant microorganism containing one or more such heterologous nucleic acid molecules. The invention also provides a method for desulfurizing a fossil fuel containing thiophene and/or one or more substituted thiophenes. The method comprises contacting the fossil fuel with an organism containing a recombinant nucleic acid molecule which encodes an enzyme which catalyzes the desulfurization of thiophene.
    Type: Grant
    Filed: February 26, 1998
    Date of Patent: May 22, 2001
    Assignee: Energy Biosystems Corporation
    Inventors: Yongzhao Wang, John D. Childs, Charles H. Squires
  • Patent number: 5985650
    Abstract: The invention relates to the discovery that the rate of reaction of the desulfurization of fossil fuels is enhanced by the addition of a flavoprotein to the biocatalyst. The invention is drawn to a method for enhancing the rate of desulfurizing a fossil fuel containing organic sulfur compounds, comprising the steps of:a) contacting the fossil fuel with an aqueous phase containing a biocatalyst capable of cleaving carbon-sulfur bonds and a rate-enhancing amount of a flavoprotein, thereby forming a fossil fuel and aqueous phase mixture;b) maintaining the mixture of step (a) under conditions sufficient for cleavage of the carbon-sulfur bonds of the organic sulfur molecules by the biocatalyst, thereby resulting in a fossil fuel having a reduced organic sulfur content; andc) separating the fossil fuel having a reduced organic sulfur content from the resulting aqueous phase.
    Type: Grant
    Filed: February 18, 1998
    Date of Patent: November 16, 1999
    Assignee: Energy BioSystems Corporation
    Inventors: Charles H. Squires, Wan Ji, Lei Xi, Beatrice C. Ortego, Olga S. Pogrebinsky, Kevin A. Gray, John D. Childs
  • Patent number: 5952208
    Abstract: The present invention provides novel recombinant pseudomonads which contain a heterologous nucleic acid molecule comprising a nucleotide sequence encoding one or more desulfurization enzymes which are components of a biodesulfurization catalyst. The invention also provides a method of desulfurizing a carbonaceous material, such as a fossil fuel, which comprises organosulfur compounds. The method includes the steps of The method comprises the steps of (1) contacting the fossil fuel with an aqueous phase containing a recombinant biocatalyst which is capable of cleaving carbon-sulfur bonds and, optionally, a flavoprotein, thereby forming a fossil fuel and aqueous phase mixture; (2) maintaining the mixture under conditions sufficient for cleavage of the carbon-sulfur bonds of the organosulfur molecules by the biocatalyst, thereby resulting in a fossil fuel having a reduced organic sulfur content; and (3) separating the fossil fuel having a reduced organic sulfur content from the resulting aqueous phase.
    Type: Grant
    Filed: May 5, 1997
    Date of Patent: September 14, 1999
    Assignee: Energy BioSystems Corporation
    Inventors: Aldis Darzins, Lei Xi, John D. Childs, Daniel J. Monticello, Charles H. Squires
  • Patent number: 5919683
    Abstract: The invention provides a novel flavin reductase, which has been isolated from Rhodococcus strain sp. IGTS8 and purified to homogeneity. The flavin reductase is of use in the biocatalytic desulfurization of a fossil fuel containing organic sulfur compounds. The method comprises the steps of (1) contacting the fossil fuel with an aqueous phase containing a biocatalyst capable of cleaving carbon-sulfur bonds and a rate-enhancing amount of the flavin reductase of the present invention, thereby forming a fossil fuel and aqueous phase mixture; (2) maintaining the mixture under conditions sufficient for cleavage of the carbon-sulfur bonds of the organic sulfur molecules by the biocatalyst, thereby resulting in a fossil fuel having a reduced organic sulfur content; and (3) separating the fossil fuel having a reduced organic sulfur content from the resulting aqueous phase.
    Type: Grant
    Filed: June 26, 1998
    Date of Patent: July 6, 1999
    Assignee: Energy BioSystems Corporation
    Inventors: Kevin A. Gray, John D. Childs, Charles H. Squires
  • Patent number: 5804433
    Abstract: The invention provides a novel flavin reductase, which has been isolated from Rhodococcus strain sp. IGTS8 and purified to homogeneity. The flavin reductase is of use in the biocatalytic desulfurization of a fossil fuel containing organic sulfur compounds. The method comprises the steps of (1) contacting the fossil fuel with an aqueous phase containing a biocatalyst capable of cleaving carbon-sulfur bonds and a rate-enhancing amount of the flavin reductase of the present invention, thereby forming a fossil fuel and aqueous phase mixture; (2) maintaining the mixture under conditions sufficient for cleavage of the carbon-sulfur bonds of the organic sulfur molecules by the biocatalyst, thereby resulting in a fossil fuel having a reduced organic sulfur content; and (3) separating the fossil fuel having a reduced organic sulfur content from the resulting aqueous phase.
    Type: Grant
    Filed: October 23, 1996
    Date of Patent: September 8, 1998
    Assignee: Energy BioSystems Corporation
    Inventors: Kevin A. Gray, John D. Childs, Charles H. Squires
  • Patent number: 5733773
    Abstract: The invention relates to the discovery that the rate of reaction of the desulfurization of fossil fuels is enhanced by the addition of a flavoprotein to the biocatalyst. The invention is drawn to a method for enhancing the rate of desulfurizing a fossil fuel containing organic sulfur compounds, comprising the steps of:a) contacting the fossil fuel with an aqueous phase containing a biocatalyst capable of cleaving carbon-sulfur bonds and a rate-enhancing amount of a flavoprotein, thereby forming a fossil fuel and aqueous phase mixture;b) maintaining the mixture of step (a) under conditions sufficient for cleavage of the carbon-sulfur bonds of the organic sulfur molecules by the biocatalyst, thereby resulting in a fossil fuel having a reduced organic sulfur content; andc) separating the fossil fuel having a reduced organic sulfur content from the resulting aqueous phase.
    Type: Grant
    Filed: June 12, 1996
    Date of Patent: March 31, 1998
    Assignee: Energy BioSystems Corporation
    Inventors: Charles H. Squires, Wan Ji, Lei Xi, Beatrice C. Ortego, Olga S. Pogrebinsky, Kevin A. Gray, John D. Childs