# US 11,306,304 B2 · Mutations in iron-sulfur cluster proteins that improve xylose utilization > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,306,304 B2 - Document ID: US11306304B2 - Status: Granted - Kind: B2 - Application number: 16/575,350 - Filed: 2019-09-18 - Published: 2020-04-16 - Granted: 2022-04-19 - Earliest claimed: 2014-08-11 - Assignees: Lallemand Hungary Liquidity Management LLC - Applicants: Lallemand Hungary Liquidity Management LLC - Inventors: Allan Froehlich; Brooks Henningsen; Sean Covalla; Rintze M. Zelle - Web page: https://patentgrep.com/patent/US11306304B2 ## CPC - C12N 9/92: Glucose isomerase {(5.3.1.5; 5.3.1.9; 5.3.1.18)} - C07K 14/395: from Saccharomyces - C12P 7/06: Ethanol, i.e. non-beverage - C12Y 503/01005: Xylose isomerase (5.3.1.5) - Y02E 50/10: Biofuels, e.g. bio-diesel - C12N: MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA (microbiological testing media C12Q1/00) - C07K: PEPTIDES (peptides in foodstuffs A23; obtaining protein compositions for foodstuffs, working-up proteins for foodstuffs A23J; preparations for medicinal purposes A61K; peptides containing beta-lactam rings C07D; cyclic dipeptides not having in their molecule any other peptide link than those which form their ring, e.g. piperazine-2,5-diones, C07D; ergot alkaloids of the cyclic peptide type C07D519/02; macromolecular compounds having statistically distributed amino acid units in their molecules, i.e. when the preparation does not provide for a specific; but for a random sequence of the amino acid units, homopolyamides and block copolyamides derived from amino acids C08G69/00; macromolecular products derived from proteins C08H1/00; preparation of glue or gelatine C09H; single cell proteins, enzymes C12N; genetic engineering processes for obtaining peptides C12N15/00; compositions for measuring or testing processes involving enzymes C12Q; investigation or analysis of biological material G01N33/00) - C12P: FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIRED CHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERS FROM A RACEMIC MIXTURE {(brewing of beer C12C; producing vinegar C12J; producing specific peptides or proteins C07K; producing enzymes C12N9/00; DNA or RNA concerning genetic engineering, vectors, e.g. plasmids, or their isolation, preparation or purification C12N15/00; measuring or testing processes involving enzymes or microorganisms C12Q; measuring or testing processes involving nucleic acid amplification reactions C12Q1/6844; fermentation processes to form a food composition, A21 or A23; compounds in general, see the relevant compound class, e.g. C01, C07)} - C12Y: ENZYMES - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract There is provided an engineered host cells comprising (a) one or more mutations in one or more endogenous genes encoding a protein associated with iron metabolism; and (b) at least one gene encoding a polypeptide having xylose isomerase activity, and methods of their use thereof. ## Claims ### Claim 1 A recombinant yeast cell comprising (a) at least one heterologous gene encoding a protein associated with iron metabolism and/or one or more mutations in one or more endogenous gene encoding a protein associated with iron metabolism; and (b) at least one heterologous gene encoding a polypeptide having xylose isomerase activity; wherein the gene encoding a protein associated with iron metabolism is YFH1. ### Claim 2 (depends on 1) The recombinant yeast cell of claim 1, wherein the YFH1 gene encodes a polypeptide having at least 80% sequence identity to SEQ ID NO: 31 and comprising a T163P substitution. ### Claim 3 (depends on 1) The recombinant yeast cell of claim 1, wherein the heterologous gene (b) encodes a polypeptide having at least 80%, 85%, 90%, 95% or 100% sequence identity with an amino acid sequence selected from the group consisting of SEQ ID NOs: 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, and 37. ### Claim 4 (depends on 1) The recombinant yeast cell of claim 1, wherein the recombinant yeast cell further comprises at least one genetic modification of one or more endogenous genes encoding a protein of the pentose phosphate pathway. ### Claim 5 (depends on 4) The recombinant yeast cell of claim 4, wherein the recombinant yeast cell comprises at least one genetic modification in at least one of the endogenous genes selected from the group consisting of XKS1, RKI1, RPE1, TKL1, and TAL1. ### Claim 6 (depends on 5) The recombinant yeast cell of claim 5, wherein the recombinant yeast cell further comprises a deletion or disruption of one or more aldose reductase genes. ### Claim 7 (depends on 6) The recombinant yeast cell of claim 6, wherein the aldose reductase gene is GRE3 or YPR1. ### Claim 8 (depends on 7) The recombinant yeast cell of claim 7, wherein the yeast cell further comprises a modification of the endogenous PGM1 gene. ### Claim 9 (depends on 1) The recombinant yeast cell of claim 1, wherein the recombinant yeast cell comprises heterologous expression of one or more polynucleotides encoding XKS1, RKI1, RPE1, TKL1, and/or TAL1. ### Claim 10 (depends on 1) The recombinant yeast cell of claim 1, wherein the at least one heterologous gene encoding a protein associated with iron metabolism and/or the one or more mutations in one or more endogenous gene encoding a protein associated with iron metabolism confers on the recombinant yeast cell an increased ability to utilize xylose as compared to a similar yeast cell lacking the one or more mutations. ### Claim 11 (depends on 1) The recombinant yeast cell of claim 1, wherein the recombinant yeast cell is a member of a genus selected from the group consisting of Saccharomyces, Kluyveromyces, Candida, Pichia, Schizosaccharomyces, Hansenula, Kloeckera, Schwanniomyces, and Yarrowia. ### Claim 12 (depends on 1) The recombinant yeast cell of claim 1, wherein the recombinant yeast cell is S. cerevisiae. ### Claim 13 (depends on 1) A method for producing a fermentation product comprising contacting the recombinant yeast cell of claim 1 with a carbon source, wherein said carbon source comprises xylose and/or xylan. ### Claim 14 (depends on 13) A method of claim 13, wherein the fermentation product is ethanol. ### Claim 15 (depends on 2) A method for producing a fermentation product comprising contacting the recombinant yeast cell of claim 2 with a carbon source, wherein said carbon source comprises xylose and/or xylan. ### Claim 16 (depends on 15) A method of claim 15, wherein the fermentation product is ethanol.