# US 5,349,123 A · Glycogen biosynthetic enzymes in plants > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,349,123 A - Document ID: US5349123A - Status: Granted - Kind: A - Application number: 07/735,065 - Filed: 1991-07-24 - Granted: 1994-09-20 - Earliest claimed: 1990-12-21 - Assignees: Calgene, Inc. - Inventors: Christine K. Shewmaker; David M. Stalker - Web page: https://patentgrep.com/patent/US5349123A ## CPC - C12N 9/1051: {Hexosyltransferases (2.4.1)} - C12N 9/1241: {Nucleotidyltransferases (2.7.7)} - C12N 15/8245: {involving modified carbohydrate or sugar alcohol metabolism, e.g. starch biosynthesis} - C07K 2319/00: Fusion polypeptide - C07K 2319/02: containing a signal sequence - 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) ## Abstract This invention relates to glycogen biosynthesis enzymes in plants. In particular, this invention is directed to plant cells having a DNA sequence encoding a glycogen biosynthesis enzyme integrated in its genome as the result of genetic engineering. Cells containing a DNA or RNA (mRNA) sequence encoding the enzyme as well as cells containing the enzyme are also provided. Plants and, more particularly, plant parts may also be obtained which contain glycogen biosynthesis enzyme sequences and/or containing such glycogen biosynthesis enzymes. ## Claims ### Claim 1 A nucleic acid construct comprising the encoding sequence from an E. coli glgA gene and a plant plastid transit peptide encoding sequence. ### Claim 2 (depends on 1) The construct of claim 1 wherein said glgA gene is from E. coli strain 618. ### Claim 3 (depends on 1) The construct of claim 1 comprising in the 5'-3' direction of transcription, a transcription initiation region, a translational initiation region, said plastid transit peptide encoding sequence, said E. coli glgA encoding sequence, and a transcription/translational termination region, wherein said transcription initiation region is capable of functioning in a plant cell. ### Claim 4 (depends on 3) The construct of claim 3 wherein said transcription initiation region comprises the regulatory region 5' to a patatin gene from Solanum tuberosum. ### Claim 5 (depends on 3) The construct of claim 3 further comprising a T-DNA border. ### Claim 6 A plant cell comprising E. coli glycogen synthase. ### Claim 7 (depends on 6) The plant cell of claim 6 wherein said enzyme is present in an amyloplast. ### Claim 8 (depends on 6) The plant cell of claim 6 wherein said plant is selected from the group consisting of corn, sorghum, rice, potato, tapioca, cassava, arrowroot, and sago. ### Claim 9 (depends on 6) The plant cell of claim 6, wherein said plant is a cereal grain plant. ### Claim 10 (depends on 6, 7, 8) A plant comprising a cell of any one of claims 6, 7, 8, or 9. ### Claim 11 (depends on 3) A method to modify a potato tuber, wherein said method comprises growing a potato plant, under conditions that will permit the formation of a potato tuber, wherein the genome of said potato plant comprises a construct according to claim 3, and wherein said transcription initiation region is from a patatin gene. ### Claim 12 (depends on 11) The method of claim 11 wherein expression of said E. coli glycogen synthase results in modification of the starch composition of said potato tuber. ### Claim 13 (depends on 12) The method of claim 12 wherein said modified starch has an altered amylose to amylopectin ratio as compared to that of a control starch storage organ. ### Claim 14 (depends on 11) The method of claim 11 wherein said potato tuber comprises modified starch having an altered ratio of low to high molecular weight chains in the amylopectin fraction of said starch, as compared to that of a control potato tuber. ### Claim 15 (depends on 11) A potato tuber having modified starch, wherein said starch modification consists of an increased percentage of low molecular weight chains in the amylopectin portion of said starch, and wherein said potato tuber is produced according to the method of claim 11. ### Claim 16 (depends on 15) The potato tuber of claim 15, wherein the amylopectin fraction of the starch in said potato tuber has a ratio of low to high molecular weight chains of at least 4.0.