Patents by Inventor Kensaku Sakamoto

Kensaku Sakamoto 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).

  • Publication number: 20210107997
    Abstract: The present invention relates to a monoclonal antibody or antibody fragment thereof as a human IgG antibody including at least one lysine derivative in a constant region of the human IgG antibody; a modified antibody or antibody fragment thereof, wherein the lysine derivative is modified; a nucleic acid including a nucleotide sequence encoding the antibody or antibody fragment thereof; a vector including the nucleic acid; a transformed cell obtained by introducing the vector into a host cell; a method for producing the antibody or antibody fragment thereof; and a composition containing the antibody or antibody fragment thereof.
    Type: Application
    Filed: December 22, 2020
    Publication date: April 15, 2021
    Applicants: RIKEN, KYOWA KIRIN CO., LTD.
    Inventors: Kensaku Sakamoto, Kazumasa Ohtake, Yoshimi Yamaguchi, Shigeyuki Yokoyama, Tatsuo Yanagisawa, Akiko Matsumoto, Akifumi Kato, Yasuhisa Shiraishi, Kaname Kimura, Masakazu Homma
  • Patent number: 10906990
    Abstract: The present invention relates to a monoclonal antibody or antibody fragment thereof as a human IgG antibody including at least one lysine derivative in a constant region of the human IgG antibody; a modified antibody or antibody fragment thereof, wherein the lysine derivative is modified; a nucleic acid including a nucleotide sequence encoding the antibody or antibody fragment thereof; a vector including the nucleic acid; a transformed cell obtained by introducing the vector into a host cell; a method for producing the antibody or antibody fragment thereof; and a composition containing the antibody or antibody fragment thereof.
    Type: Grant
    Filed: August 18, 2016
    Date of Patent: February 2, 2021
    Assignees: RIKEN, KYOWA KIRIN CO., LTD.
    Inventors: Kensaku Sakamoto, Kazumasa Ohtake, Yoshimi Yamaguchi, Shigeyuki Yokoyama, Tatsuo Yanagisawa, Akiko Matsumoto, Akifumi Kato, Yasuhisa Shiraishi, Kaname Kimura, Masakazu Homma
  • Publication number: 20190127488
    Abstract: The present invention relates to a monoclonal antibody or antibody fragment thereof as a human IgG antibody including at least one lysine derivative in a constant region of the human IgG antibody; a modified antibody or antibody fragment thereof, wherein the lysine derivative is modified; a nucleic acid including a nucleotide sequence encoding the antibody or antibody fragment thereof; a vector including the nucleic acid; a transformed cell obtained by introducing the vector into a host cell; a method for producing the antibody or antibody fragment thereof; and a composition containing the antibody or antibody fragment thereof.
    Type: Application
    Filed: August 18, 2016
    Publication date: May 2, 2019
    Applicants: RIKEN, KYOWA HAKKO KIRIN CO., LTD.
    Inventors: Kensaku SAKAMOTO, Kazumasa OHTAKE, Yoshimi YAMAGUCHI, Shigeyuki YOKOYAMA, Tatsuo YANAGISAWA, Akiko MATSUMOTO, Akifumi KATO, Yasuhisa SHIRAISHI, Kaname KIMURA, Masakazu HOMMA
  • Patent number: 9340790
    Abstract: The present invention provides a novel method of producing a recombinant bacterium for production of a non-natural protein, including: (1) expressing tRNA in a bacterium, which tRNA recognizes UAG codon; (2) expressing an aminoacyl-tRNA synthetase in the bacterium, which aminoacyl-tRNA synthetase acylates the tRNA with a non-natural amino acid or an ?-hydroxy acid; (3) (i) introducing a DNA construct into the bacterium, which DNA construct is for expressing, in the absence of a release factor for terminating translation at UAG codon, a function of at least one gene selected from the group consisting of genes each of which loses its function when a gene that codes for the release factor is defective and/or introducing an alteration into said at least one gene in a chromosome of the bacterium, which alteration is for expressing the function of said at least one gene in the absence of the release factor; and (4) causing the gene that codes for the release factor in the bacterium to be defective.
    Type: Grant
    Filed: June 16, 2011
    Date of Patent: May 17, 2016
    Assignee: RIKEN
    Inventors: Shigeyuki Yokoyama, Takahito Mukai, Kensaku Sakamoto, Akiko Matsumoto
  • Patent number: 9133449
    Abstract: Method for incorporating a lysine derivative (particularly an N?-benzyloxycarbonyl-lysine (Z-Lys) derivative) having useful functional group such as heavy atom, selenium, reactive functional group, fluorescent group or crosslinker, which is suitable as a non-natural amino acid, into a desired protein in a site-specific manner. A mutant pyrrolysyl-tRNA synthetase has substitution of at least one amino acid residue selected from tyrosine residue at position 306, leucine residue at position 309 and cysteine residue at position 348 each constituting a pyrrolysine-binding site in the amino acid sequence for pyrrolysyl-tRNA synthetase of SEQ ID NO:2. The substitution of the amino acid residue is: of tyrosine residue at position 306 by glycine or alanine residue, of leucine residue at position 309 by glycine or alanine residue, and/or of a cysteine residue at position 348 by valine, serine or alanine residue.
    Type: Grant
    Filed: April 8, 2014
    Date of Patent: September 15, 2015
    Assignee: RIKEN
    Inventors: Shigeyuki Yokoyama, Kensaku Sakamoto, Tatsuo Yanagisawa, Takatsugu Kobayashi
  • Publication number: 20140322751
    Abstract: Method for incorporating a lysine derivative (particularly an N?-benzyloxycarbonyl-lysine (Z-Lys) derivative) having useful functional group such as heavy atom, selenium, reactive functional group, fluorescent group or crosslinker, which is suitable as a non-natural amino acid, into a desired protein in a site-specific manner. A mutant pyrrolysyl-tRNA synthetase has substitution of at least one amino acid residue selected from tyrosine residue at position 306, leucine residue at position 309 and cysteine residue at position 348 each constituting a pyrrolysine-binding site in the amino acid sequence for pyrrolysyl-tRNA synthetase of SEQ ID NO:2. The substitution of the amino acid residue is: of tyrosine residue at position 306 by glycine or alanine residue, of leucine residue at position 309 by glycine or alanine residue, and/or of a cysteine residue at position 348 by valine, serine or alanine residue.
    Type: Application
    Filed: April 8, 2014
    Publication date: October 30, 2014
    Applicant: Riken
    Inventors: Shigeyuki YOKOYAMA, Kensaku SAKAMOTO, Tatsuo YANAGISAWA, Takatsugu KOBAYASHI
  • Patent number: 8822180
    Abstract: There are provided a DNA construct comprising a suppressor tRNA gene of a non-eukaryote containing no internal promoter functioning in a eukaryotic cell, and a eukaryotic or bacteriophage promoter linked at the 5? end of the tRNA gene, a method for synthesizing a suppressor tRNA by using the DNA construct, and a process for producing protein incorporating a non-natural amino acid by using the same.
    Type: Grant
    Filed: April 30, 2012
    Date of Patent: September 2, 2014
    Assignee: Riken
    Inventors: Shigeyuki Yokoyama, Kensaku Sakamoto, Nobumasa Hino, Takahito Mukai, Takatsugu Kobayashi
  • Patent number: 8785152
    Abstract: A non-natural protein having at least one ester bond in its polypeptide main chain is synthesized by using an in vivo translation system in a ribosome. The following components (a) to (c) are expressed in a cell or an cell extraction solution in the presence of an ?-hydroxy acid: (a) an aminoacyl-tRNA synthetase which can activate the ?-hydroxy acid; (b) suppressor tRNA which can bind to the ?-hydroxy acid in the presence of the aminoacyl-tRNA synthetase; and (c) a gene encoding a desired protein having a nonsense mutation or a frame-shift mutation at a desired site.
    Type: Grant
    Filed: November 21, 2008
    Date of Patent: July 22, 2014
    Assignee: Riken
    Inventors: Shigeyuki Yokoyama, Kensaku Sakamoto, Tatsuo Yanagisawa, Takahito Mukai, Takatsugu Kobayashi
  • Patent number: 8735093
    Abstract: Method for incorporating a lysine derivative (particularly an N?-benzyloxycarbonyl-lysine (Z-Lys) derivative) having useful functional group such as heavy atom, selenium, reactive functional group, fluorescent group or crosslinker, which is suitable as a non-natural amino acid, into a desired protein in a site-specific manner. A mutant pyrrolysyl-tRNA synthetase has substitution of at least one amino acid residue selected from tyrosine residue at position 306, leucine residue at position 309 and cysteine residue at position 348 each constituting a pyrrolysine-binding site in the amino acid sequence for pyrrolysyl-tRNA synthetase of SEQ ID NO:2. The substitution of the amino acid residue is: of tyrosine residue at position 306 by glycine or alanine residue, of leucine residue at position 309 by glycine or alanine residue, and/or of a cysteine residue at position 348 by valine, serine or alanine residue.
    Type: Grant
    Filed: March 18, 2010
    Date of Patent: May 27, 2014
    Assignee: Riken
    Inventors: Shigeyuki Yokoyama, Kensaku Sakamoto, Tatsuo Yanagisawa, Takatsugu Kobayashi
  • Patent number: 8642291
    Abstract: Producing proteins incorporating non-natural amino acids can involve introducing genes into and knocking inherent genes out of eukaryote-type cells. Genes to be introduced include genes encoding eukaryote-type aminoacyl tRNA synthetase mutants having enhanced specificity to non-natural amino acids, compared with specificity to similar natural amino acids, and tRNA genes for non-natural amino acids capable of binding to the non-natural amino acids in the presence of the eukaryote-type aminoacyl tRNA synthetase mutants. Inherent genes to be knocked out include genes encoding aminoacyl tRNA synthetase having specificity to natural amino acids and tRNA genes capable of binding to the natural amino acids in the presence of the inherent aminoacyl tRNA synthetase.
    Type: Grant
    Filed: May 14, 2012
    Date of Patent: February 4, 2014
    Assignee: RIKEN
    Inventors: Shigeyuki Yokoyama, Kensaku Sakamoto, Fumie Iraha
  • Publication number: 20130130313
    Abstract: There are provided a DNA construct comprising a suppressor tRNA gene of a non-eukaryote containing no internal promoter functioning in a eukaryotic cell, and a eukaryotic or bacteriophage promoter linked at the 5? end of the tRNA gene, a method for synthesizing a suppressor tRNA by using the DNA construct, and a process for producing protein incorporating a non-natural amino acid by using the same.
    Type: Application
    Filed: April 30, 2012
    Publication date: May 23, 2013
    Applicant: RIKEN
    Inventors: Shigeyuki YOKOYAMA, Kensaku Sakamoto, Nobumasa Hino, Takahito Mukai, Takatsugu Kobayashi
  • Publication number: 20130095524
    Abstract: The present invention provides a novel method of producing a recombinant bacterium for production of a non-natural protein, including: (1) expressing tRNA in a bacterium, which tRNA recognizes UAG codon; (2) expressing an aminoacyl-tRNA synthetase in the bacterium, which aminoacyl-tRNA synthetase acylates the tRNA with a non-natural amino acid or an ?-hydroxy acid; (3) (i) introducing a DNA construct into the bacterium, which DNA construct is for expressing, in the absence of a release factor for terminating translation at UAG codon, a function of at least one gene selected from the group consisting of genes each of which loses its function when a gene that codes for the release factor is defective and/or introducing an alteration into said at least one gene in a chromosome of the bacterium, which alteration is for expressing the function of said at least one gene in the absence of the release factor; and (4) causing the gene that codes for the release factor in the bacterium to be defective.
    Type: Application
    Filed: June 16, 2011
    Publication date: April 18, 2013
    Applicant: RIKEN
    Inventors: Shigeyuki Yokoyama, Takahito Mukai, Kensaku Sakamoto, Akiko Matsumoto
  • Publication number: 20120276589
    Abstract: Producing proteins incorporating non-natural amino acids can involve introducing genes into and knocking inherent genes out of eukaryote-type cells. Genes to be introduced include genes encoding eukaryote-type aminoacyl tRNA synthetase mutants having enhanced specificity to non-natural amino acids, compared with specificity to similar natural amino acids, and tRNA genes for non-natural amino acids capable of binding to the non-natural amino acids in the presence of the eukaryote-type aminoacyl tRNA synthetase mutants. Inherent genes to be knocked out include genes encoding aminoacyl tRNA synthetase having specificity to natural amino acids and tRNA genes capable of binding to the natural amino acids in the presence of the inherent aminoacyl tRNA synthetase.
    Type: Application
    Filed: May 14, 2012
    Publication date: November 1, 2012
    Applicant: RIKEN
    Inventors: Shigeyuki Yokoyama, Kensaku Sakamoto, Fumie Iraha
  • Patent number: 8293512
    Abstract: A polypeptide according to the present invention includes: an altered polypeptide obtained by altering an ArgRS, a CysRS, a MetRS, a GlnRS, a GluRS, a LysRS, a TyrRS, or a TrpRS so that an unnatural amino acid is recognized; and an editing polypeptide derived from a PheRS, a LeuRS, an IleRS, a ValRS, an AlaRS, a ProRS, or a ThrRS, the editing polypeptide having been either inserted between a Rossman-fold N domain and a Rossman-fold C domain that exist in the altered polypeptide, or bound to an N terminal of the altered polypeptide. Thus provided are a new aaRS that exhibits high substrate specificity to an unnatural amino acid and a technique that involves the use of such an aaRS.
    Type: Grant
    Filed: July 11, 2011
    Date of Patent: October 23, 2012
    Assignee: Riken
    Inventors: Shigeyuki Yokoyama, Kensaku Sakamoto, Kenji Oki, Takahito Mukai
  • Patent number: 8183013
    Abstract: This invention provides a method for producing proteins into which non-natural amino acids have been incorporated at desired positions involving the use of either prokaryote-derived or eukaryote-type aaRS* and prokaryotic cells or eukaryote-type as host cells, the method comprising steps of: (a) introducing genes encoding prokaryote-derived aminoacyl tRNA synthetase mutants having enhanced specificity to non-natural amino acids similar to given natural amino acids (compared with specificity to the natural amino acids) and tRNA genes for non-natural amino acids capable of binding to the non-natural amino acids in the presence of the prokaryote-derived aminoacyl tRNA synthetase mutants into prokaryotic cells that express genes encoding eukaryote-type aminoacyl tRNA synthetase having specificity to the given natural amino acids and tRNA genes capable of binding to the natural amino acids in the presence of eukaryote-type aminoacyl tRNA synthetase; and (b) knocking out genes encoding aminoacyl tRNA synthetase hav
    Type: Grant
    Filed: November 24, 2006
    Date of Patent: May 22, 2012
    Assignee: Riken
    Inventors: Shigeyuki Yokoyama, Kensaku Sakamoto, Fumie Iraha
  • Patent number: 8168407
    Abstract: There are provided a DNA construct comprising non-eukaryote-derived suppressor tRNA gene containing no internal promoter functioning in a eukaryotic cell, and a eukaryote-derived or bacteriophage-derived promoter linked at the 5? end of the tRNA gene, a method for synthesizing a suppressor tRNA by using the DNA construct, and a process for producing a non-natural amino acid-incorporated protein by using the same.
    Type: Grant
    Filed: August 21, 2008
    Date of Patent: May 1, 2012
    Assignee: Riken
    Inventors: Shigeyuki Yokoyama, Kensaku Sakamoto, Nobumasa Hino, Takahito Mukai, Takatsugu Kobayashi
  • Publication number: 20120028330
    Abstract: A polypeptide according to the present invention includes: an altered polypeptide obtained by altering an ArgRS, a CysRS, a MetRS, a GlnRS, a GluRS, a LysRS, a TyrRS, or a TrpRS so that an unnatural amino acid is recognized; and an editing polypeptide derived from a PheRS, a LeuRS, an IleRS, a ValRS, an AlaRS, a ProRS, or a ThrRS, the editing polypeptide having been either inserted between a Rossman-fold N domain and a Rossman-fold C domain that exist in the altered polypeptide, or bound to an N terminal of the altered polypeptide. Thus provided are a new aaRS that exhibits high substrate specificity to an unnatural amino acid and a technique that involves the use of such an aaRS.
    Type: Application
    Filed: July 11, 2011
    Publication date: February 2, 2012
    Applicant: RIKEN
    Inventors: Shigeyuki Yokoyama, Kensaku Sakamoto, Kenji Oki, Takahito Mukai
  • Publication number: 20110136168
    Abstract: A non-natural protein having at least one ester bond in its polypeptide main chain is synthesized by using an in vivo translation system in a ribosome. The following components (a) to (c) are expressed in a cell or an cell extraction solution in the presence of an ?-hydroxy acid: (a) an aminoacyl-tRNA synthetase which can activate the ?-hydroxy acid; (b) suppressor tRNA which can bind to the ?-hydroxy acid in the presence of the aminoacyl-tRNA synthetase; and (c) a gene encoding a desired protein having a nonsense mutation or a frame-shift mutation at a desired site.
    Type: Application
    Filed: November 21, 2008
    Publication date: June 9, 2011
    Inventors: Shigeyuki Yokoyama, Kensaku Sakamoto, Tatsuo Yanagisawa, Takahito Mukai, Takatsugu Kobayashi
  • Publication number: 20100304431
    Abstract: The present invention relates to a process for producing a protein having an unnatural amino acid introduced therein, the process including: expressing in a eukaryotic cell an aminoacyl-tRNA synthetase, a nucleic acid having a sequence containing a eukaryote-derived tRNA nucleotide sequence linked to the 5? end of a tRNA nucleotide sequence that is ligated with to an unnatural amino acid in the presence of the aminoacyl-tRNA synthetase, an unnatural amino acid, and a gene of a desired protein having a nonsense mutation at a predetermined position, to integrate the unnatural amino acid at the nonsense mutation position into the protein, thereby expressing a protein having an unnatural amino acid introduced therein.
    Type: Application
    Filed: August 2, 2006
    Publication date: December 2, 2010
    Inventors: Shigeyuki Yokoyama, Kensaku Sakamoto, Tatsuo Yanagisawa, Takatsugu Kobayashi
  • Publication number: 20100267087
    Abstract: Method for incorporating a lysine derivative (particularly an N?-benzyloxycarbonyl-lysine (Z-Lys) derivative) having useful functional group such as heavy atom, selenium, reactive functional group, fluorescent group or crosslinker, which is suitable as a non-natural amino acid, into a desired protein in a site-specific manner. A mutant pyrrolysyl-tRNA synthetase has substitution of at least one amino acid residue selected from tyrosine residue at position 306, leucine residue at position 309 and cysteine residue at position 348 each constituting a pyrrolysine-binding site in the amino acid sequence for pyrrolysyl-tRNA synthetase of SEQ ID NO:2. The substitution of the amino acid residue is: of tyrosine residue at position 306 by glycine or alanine residue, of leucine residue at position 309 by glycine or alanine residue, and/or of a cysteine residue at position 348 by valine, serine or alanine residue.
    Type: Application
    Filed: March 18, 2010
    Publication date: October 21, 2010
    Applicant: RIKEN
    Inventors: SHIGEYUKI YOKOYAMA, KENSAKU SAKAMOTO, TATSUO YANAGISAWA, TAKATSUGU KOBAYASHI