Methionine; Cysteine; Cystine Patents (Class 435/113)
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Patent number: 5622845Abstract: The present invention provides an inexpensive fermentation medium for growing microorganisms. Also provided are fermentation media and methods for producing norleucine by growing E. coli thereon, fermentation media and methods for incorporating norleucine into polypeptides expressed by microorganisms grown thereon, and fermentation media and methods for preventing the incorporation of norleucine into polypeptides expressed by microorganisms grown thereon. Also provided are bovine somatotropin analogs.Type: GrantFiled: June 6, 1995Date of Patent: April 22, 1997Assignee: The Upjohn CompanyInventors: David P. Brunner, Gary C. Harbour, Richard J. Kirschner, James F. Pinner, Robert L. Garlick
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Patent number: 5516660Abstract: The invention relates to novel microorganisms, their use and method of producing L-.alpha.-amino acids. In particular, microorganisms DSM 7329 and 7330 are suitable for the production of L-.alpha.-amino acids from corresponding hydantoins or carbamoyl-.alpha.-amino acids. These novel microorganisms are simple to cultivate and make possible high L-.alpha.-amino acid yields from different substrates.Type: GrantFiled: May 19, 1994Date of Patent: May 14, 1996Assignee: Degussa AktiengesellschaftInventors: Fritz Wagner, Dirk Volkel, Andreas Bommarius, Karlheinz Drauz
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Patent number: 5360742Abstract: The claimed invention provides a eukaryotic plasmid vector which upon expression provides the enzymes required for cysteine biosynthesis, the vector preferably allowing for expression of these enzymes and concomitant production of cysteine in ruminal mucosa cells. The vector of the instant invention is engineered using recombinant techniques to insert microbial genes encoding serine acetyltransferase (SAT) and O-acetylserine sulphydrolase (OASS), preferably the isolated Salmonella typhimurium genes cysE encoding for SAT and cysK or cysM encoding for OASS, driven by a promoter efficient in a eukaryotic host cell, such as the SV40 late promoter, into a eukaryotic cloning vector, such as Promega's pGEM-2. The construction of the instant vector also allows for an additional gene which upon expression produces human growth hormone.Type: GrantFiled: December 23, 1991Date of Patent: November 1, 1994Assignee: Luminis Pty. Ltd.Inventor: George E. Rogers
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Patent number: 5354672Abstract: Disclosed are novel bacterial cells characterized by hypersecretion of an amino acid, wherein a DNA inversion gene has been incorporated into said bacterial cells. Also disclosed are methods of producing said bacterial cells and methods of producing amino acids from said bacterial cells.Type: GrantFiled: November 24, 1992Date of Patent: October 11, 1994Inventors: Ian Fotheringham, Jennifer Ton, Chris Higgins
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Patent number: 5344767Abstract: A method of preparing a high specificity .sup.35 S-sulfide comprises preparing a reducing mixture comprising hydrochloric acid, hydriodic acid and hypophosphorus acid, substantially removing any sulfate present in the mixture, admixing the reducing mixture with a composition comprising an .sup.35 S-sulfate corresponding to a desired .sup.35 S-sulfide to obtain the .sup.35 S-sulfide, and recovering the .sup.35 S-sulfide from the admixture. The thus prepared .sup.35 S-sulfides are applicable to the synthesis of high specificity .sup.35 S amino acids and derivatives thereof by sulfhydrylation, e.g., in the presence of an enzyme and a .sup.35 S-sulfide or sulfhydric acid and the O-acetylated amino acid. The labeled amino acid may be separated from the reaction mixture by reverse phase chromatography.Type: GrantFiled: June 29, 1992Date of Patent: September 6, 1994Assignee: Commissariat a l'Energie AtomiqueInventors: Claude Boullais, Jean-Pierre Noel, Michel Riva
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Patent number: 5326693Abstract: A basic L-amino acid and an acidic L-amino acid may be concurrently produced by either culturing a basic L-amino acid-producing bacteria under conditions for producing an acidic L-amino acid or mix-culturing a basic L-amino acid-producing bacteria and an acidic L-amino acid-producing bacteria.Type: GrantFiled: December 8, 1992Date of Patent: July 5, 1994Assignee: Ajinomoto Co., Inc.Inventors: Hideo Kuronuma, Harufumi Miwa, Shigeru Nakamori, Toshimasa Ishii, Yasuhiko Yoshihara
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Patent number: 5244794Abstract: Root organ cultures of the monocot genus Allium were successfully grown in culture medium. In a preferred bioreactor system, the roots themselves can be grown and harvested as a source of various Allium flavors and/or the growing roots can be reacted with various nutrients to produce Allium flavor compounds independent of the root harvesting. The root cultures of the present invention produce quantities of onion and onion-like flavor compounds comparable to those found in onion bulbs.Flavor precursors arThis invention was made in part under NSF Grant No. 85-03183. The U.S. Government has certain rights to this invention.Type: GrantFiled: June 28, 1991Date of Patent: September 14, 1993Assignee: Cornell Research Foundation, Inc.Inventors: Christopher Prince, Michael L. Shuler
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Patent number: 5215897Abstract: A process for producing an L-amino acid from the corresponding DL- and/or L-amino acid amide represented by the general formula: ##STR1## wherein R is a substituted or unsubstituted alkyl group having one to 4 carbon atoms, a substituted or unsubstituted phenyl group, or a substituted or unsubstituted aralkyl group, by action of an enzyme having hydrolytic activity to L-amino acid amides which is produced by Enterobacter cloacae or Pseudomonas sp.Type: GrantFiled: May 17, 1990Date of Patent: June 1, 1993Assignee: Nitto Chemical Industries Co., Ltd.Inventors: Keiichi Sakashita, Tetsuji Nakamura, Ichiro Watanabe
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Patent number: 5212077Abstract: The invention relates to a method for producing an organic compound from manure, including the steps of:i) concentrating the manure to form a vapor;ii) condensing said vapor to form a condensate;iii) adding to said condensate micro-organisms which are capable of producing the organic compound; andiv) separating from the condensate the organic compound produced by the micro-organisms.These micro-organisms comprise species of the genera Arthrobacter, Brevibacterium, Corynebacterium, Bacillus, Escherichia, Microbacterium, Micrococcus and Pseudomonas.Type: GrantFiled: April 20, 1990Date of Patent: May 18, 1993Assignee: MeMon B.V.Inventor: Erik D. J. Bleeker
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Patent number: 5196326Abstract: A basic L-amino acid and an acidic L-amino acid may be concurrently produced by either culturing a basic L-amino acid-producing bacteria under conditions for producing an acidic L-amino acid or mix-culturing a basic L-amino acid-producing bacteria and an acidic L-amino acid-producing bacteria.Type: GrantFiled: February 15, 1991Date of Patent: March 23, 1993Assignee: Ajinomoto Co., Inc.Inventors: Hideo Kuronuma, Harufumi Miwa, Shigeru Nakamori, Toshimasa Ishii, Yasuhiko Yoshihara
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Patent number: 5128249Abstract: This invention relates to new stable sulpho-adenosyl-L-methionine (SAMe) salts and the relative production process.Said salts have the following general formula:SAMe.nR(O).sub.m (SO.sub.3 H).sub.p (I)where m can be zero or 1; n is 1.5 when p is 2, and is 3 when p is 1; R is chosen from the group consisting of alkyl, phenylalkyl and carboxyalkyl, in which the linear or branched alkyl chain contains from 8 to 18 carbon atoms.In particular, the salts according to the present invention are SAMe salts of sulphonic acids, or of sulphuric acid esters, or of dioctylsulphosuccinic acid, which fall within formula (I).The process for producing said salts consists of: a) enriching the starting yeast with SAMe; b) lysing the cells and recovering an aqueous solution rich in SAMe (cell lysate); c) purifying the lysate by ultrafiltration; d) precipitating the SAMe by treatment with one of the aforesaid acids or esters; e) separating the precipitated product, washing it and drying it under vacuum.Type: GrantFiled: May 8, 1985Date of Patent: July 7, 1992Assignee: Bioresearch S.p.a.Inventor: Federico Gennari
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Patent number: 5108914Abstract: Microorganisms with the ability to cleave enantioselectively 5-substituted hydantoins to L-alpha-amino acids are cultivated in a known manner in a batch preparation. By one-time dosage of anondegradable enzyme inductor of the structure ##STR1## (where R.sub.1, R.sub.2 and X are specifically defined) an increased enzyme activity combined with an increased reaction rate is achieved.Type: GrantFiled: December 19, 1989Date of Patent: April 28, 1992Assignee: Rutgerswerke AktiengesellschaftInventors: Fritz Wagner, Christoph Syldalk, Vera Mackowiak, Karsten Krohn, Hartmut Hoke, Albrecht Laufer
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Patent number: 5102791Abstract: The present invention relates to new stable sulpho-adenosyl-L-methionine (SAMe) salts particulary suitable for parenteral use, their production process, and pharmaceutical compositions containing them as active principles.Said salts correspond to the general formula:SAMe.n(CH.sub.2).sub.m (SO.sub.3 H).sub.2 (I)where n can vary from 1 to 2 and m can vary from 3 to 12.The process for producing said salts consists of the following stages: a) enriching the starting yeast with SAMe; b) lysing the cells and recovering a solution rich in SAMe (cell lysate); c) prepurifying the cell lysate by ultrafiltration; d) passing the prepurified lysate through a column of weak acid ion exchange resin and eluting with the required disulphonic acid; e) passing the eluate of said column through a colum of absorption resin and washing with the required disulphonic acid; f) concentrating the eluate of the later column by reverse osmosis; g) drying the concentrated solution.Type: GrantFiled: May 9, 1985Date of Patent: April 7, 1992Assignee: Bioresearch S.p.A.Inventor: Fedrico Gennari
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Patent number: 5100782Abstract: The disclosure relates to a process for the preparation of L-amino acids of general Formula I ##STR1## wherein A means the residue of an amino acid molecule, from D,L-aminonitriles of general Formula II ##STR2## wherein A has the meaning given above, characterized by fermenting the .alpha.-aminonitriles with a culture of Actinetobacter calcoaceticus DSM 3875 and reacting the thus-obtained D,L-amino acid amides of general Formula III ##STR3## wherein A has the meaning given above, with a culture of a microorganism containing amino acid amide racemases and L-amino acid amide amidases.Type: GrantFiled: January 5, 1990Date of Patent: March 31, 1992Assignee: Schering AktiengesellschaftInventors: Uwe Klages, Alfred Weber
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Patent number: 5071752Abstract: Process is described for the production of L-amino acids of general formula I ##STR1## in which R.sub.1 means an alkyl radical with at most 12 carbon atoms optionally substituted by hydroxy groups, mercapto groups, halogen atoms, amino groups, carbonyl groups or guanidino groups and/or interrupted by oxygen atoms, nitrogen atoms or sulfur atoms, and in the case of mercapto compounds of formula I also their dithio compounds, characterized in that the microorganism Nocardia spec. DSM 3306 or its enzymes are allowed to act on a D,L-imidazolidinedione derivative of general formula II ##STR2## in which R.sub.1 has the above-named meaning or, in the case of mercapto compounds of formula II, also in their dithio compounds.Type: GrantFiled: September 23, 1988Date of Patent: December 10, 1991Assignee: Schering AktiengesellschaftInventors: Uwe Klages, Alfred Weber, Ludwig Wilschowitz
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Patent number: 5068187Abstract: The 5-substituted hydantoins represented below can be transformed into D-.alpha.-amino acids by the use of the cultured broth, cells or treated cells of the genus Hansenula:5-substituted hydantoins: ##STR1## wherein R represents an alkyl, substituted alkyl, phenyl or substituted phenyl group.D-.alpha.-amino acids: ##STR2## wherein R represents the same meanings as above.Type: GrantFiled: March 28, 1989Date of Patent: November 26, 1991Assignee: Mitsui Toatsu Chemicals, Inc.Inventors: Mamoru Takeichi, Naoshi Hagihara, Hitoshi Tarukawa, Shinichirou Tawaki, Nobuyoshi Makiguchi
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Patent number: 4880738Abstract: A biocatalytic method for producing a desired amino acid is disclosed. The method involves contacting a 2-ketoacid corresponding to the desired amino acid with lactic acid, aspartic acid and ammonia, or salts thereof, in the presence of:(a) one or more transaminase enzymes capable of catalyzing the conversion of the 2-ketoacid and L-aspartic acid to the desired amino acid and oxaloacetic acid;(b) a malate-lactate transhydrogenase enzyme capable of catalyzing the conversion of lactic acid and oxaloacetic acid to pyruvic acid and malic acid;(c) a fumarase enzyme capable of catalyzing the conversion of malic acid to fumaric acid; and(d) an aspartate-ammonia lyase enzyme capable of catalyzing the conversion of fumaric acid and ammonia to aspartic acid.Type: GrantFiled: June 13, 1986Date of Patent: November 14, 1989Assignee: Genetics Institute, Inc.Inventor: J. David Rozzell
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Patent number: 4849345Abstract: New L-phenylalanine dehydrogenases produced by a microorganism belonging to the genus Sporosarcina or Bacillus, new microorganisms capable of l-phenylalanine dehydrogenase and belonging to the genus Sporosarcina or Bacillus, a process for production of L-phenylalanine dehydrogenase using the microorganisms, and processes for production of L-amino acids using the enzymes or the microorganisms.Type: GrantFiled: April 14, 1986Date of Patent: July 18, 1989Assignee: Sagami Chemical Research CenterInventors: Yasuhisa Asano, Akiko Nakazawa, Shiro Terashima, Kiyosi Kondo, Kaori Endo, Kenji Hirai, Naganori Numao
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Patent number: 4837361Abstract: The present invention in one aspect relates to a process for the simultaneous removal of NO.sub.x and SO.sub.2 from a fluid stream comprising mixtures thereof and in another aspect relates to the separation, use and/or regeneration of various chemicals contaminated or spent in the process and which includes the steps of:(A) contacting the fluid stream at a temperature of between about 105.degree. and 180.degree. C.Type: GrantFiled: November 18, 1987Date of Patent: June 6, 1989Assignee: The United States of America as represented by the United States Department of EnergyInventors: Shih-Ger Chang, David K. Liu, Elizabeth A. Griffiths, David Littlejohn
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Patent number: 4826766Abstract: This invention relates to a process for producing a desired alpha-amino acid, AA.sub.d, or a derivative thereof. The process comprises:(a) reacting a first alpha-amino acid, AA.sub.NH.sbsb.2 ; a first alpha-keto acid, KA.sub.t ; a second alpha-keto acid, KA.sub.pre ; a first transaminase enzyme and a second transaminase enzyme to produce (i) the desired alpha-amino acid, AA.sub.d and (ii) a third alpha-keto acid, KA.sub.prod ; and(b) removing KA.sub.prod from the other keto acids, amino acids and enzymes wherein AA.sub.d and KA.sub.pre, AA.sub.t and KA.sub.t, and AA.sub.NH.sbsb.2 and KA.sub.prod are interconvertible, respectively, by amino group transfer. The first transaminase efficiently catalyzes reaction (i), but not reaction (ii) and the second transaminase efficiently catalyzes reaction (ii) but not reaction (i):AA.sub.NH.sbsb.2 +KA.sub.t .revreaction.AA.sub.t +KA.sub.prod (i)AA.sub.t +KA.sub.pre .revreaction.AA.sub.d +KA.sub.t (ii)In one embodiment KA.sub.Type: GrantFiled: September 23, 1985Date of Patent: May 2, 1989Assignee: Genetics Institute, Inc.Inventor: J. David Rozzell
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Patent number: 4820692Abstract: Compounds of the formula: ##STR1## wherein R is H, Cl, F, Br, I or R.sub.1 S--, in which R.sub.1 is C.sub.1 -C.sub.10 linear or branched chain alkyl or halogenated linear or branched chain alkyl, andwherein R.sub.2, R.sub.3 and R.sub.4 are the same or different and each is H-- or --OH,with the proviso that at least one of R.sub.2, R.sub.3 and R.sub.4 is hydroxy and the further proviso that when R.sub.2, R.sub.3 and R.sub.4 are all OH, R.sub.1 is other than methyl, are useful in inhibiting the growth of MTR kinase-dependent microorganisms and parasitic protazoans. The compounds wherein R is R.sub.1 S are novel, except those wherein R.sub.1 is methyl or isobutyl when R.sub.2, R.sub.3 and R.sub.4 are all OH.Type: GrantFiled: January 9, 1987Date of Patent: April 11, 1989Assignee: State of Oregon, acting by and through the Oregon State Board of Higher Education, acting for and on behalf of the Oregon Health Sciences University and Oregon State UniversityInventors: Michael K. Riscoe, John H. Fitchen, Adolph J. Ferro
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Patent number: 4783402Abstract: A process for producing a primary or secondary alcohol derivative of a phosopholipid which comprises reacting the phospholipid with a primary or secondary alcohol in the presence of phospholipase DM.Type: GrantFiled: April 10, 1984Date of Patent: November 8, 1988Assignee: Meito Sangyo Kabushiki KaishaInventors: Yoshitaka Kokusho, Shigeaki Kato, Haruo Machida
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Patent number: 4782020Abstract: .alpha.-Hydroxycarboxylic acids are continuously converted into the corresponding optically active .alpha.- aminocarboxylic acids. The conversion is carried out in a membrane reactor in the presence of nicotinamide-adenine dinucleotide increased in molecular weight by bonding to a water soluble high molecular weight material, a dehydrogenase specific for the .alpha.-hydroxycarboxylic acid, a dehydrogenase specific for the corresponding .alpha.-amino-carboxylic acid and ammonium ions. There is continuously supplied to the membrane reactor an aqueous solution of the .alpha.-hydroxycarboxylic acid to be reacted, a substantially lesser amount of the corresponding .alpha.-ketocarboxy lic acid, and an amount of ammonium ion at least equivalent to the .alpha.-hydroxycarboxylic acid to be reacted. There is maintained over the membrane a difference in pressure 1 and 15 bar. Behind the membrane, there is continuously drawn off a filtrate stream containing the .alpha.-aminocarboxylic acid formed.Type: GrantFiled: August 10, 1987Date of Patent: November 1, 1988Assignee: Degussa AktiengesellschaftInventors: Wolfgang Leuchtenberger, Christian Wandrey, Maria-Regina Kula
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Patent number: 4782019Abstract: A process for producing a sphingophospholipid derivative comprising reacting a sphingophospholipid with a specified compound having an alcoholic hydroxyl group selected from the group consisting of specified primary alcohol compounds, specified secondary alcohol compounds and specified saccharides or their phenol glycosides in the presence of phospholipase DM.Type: GrantFiled: April 10, 1984Date of Patent: November 1, 1988Assignee: Meito Sangyo Kabushiki KaishaInventors: Yoshitaka Kokusho, Shigeaki Kato, Haruo Machida
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Patent number: 4605625Abstract: S-adenosyl-L-homocysteine is produced by contacting adenosine with D-homocysteine in an aqueous medium in the presence of cells or treated cells of a microorganism of the genus Pseudomonas having the ability to racemize D-homocysteine to DL-homocysteine and in the presence of S-adenosyl-L-homocysteine hydrolase, to synthesize S-adenosyl-L-homocysteine, and thereafter collecting it.Type: GrantFiled: February 27, 1985Date of Patent: August 12, 1986Assignee: Nippon Zeon Co., Ltd.Inventors: Hideaki Yamada, Sakayu Shimizu, Shozo Shiozaki
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Patent number: 4599309Abstract: Yeast cells containing useful substances accumulated therein are contacted with a divalent copper ion in aqueous suspension, thereby discharging low-molecular-weight compounds in the cytoplasm out of the cells. Useful substances can be efficiently recovered both from the discharged compounds and the remaining cells.Type: GrantFiled: December 12, 1983Date of Patent: July 8, 1986Assignee: Nippon Zeon Co., Ltd.Inventors: Yoshinori Ohsumi, Takanori Sato
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Patent number: 4590161Abstract: The invention is directed to a microbiologically produced L-phenylalanine-dehydrogenase and a process for its recovery from Brevibacterium species DSM 2448. The new enzyme can be used for the enzymatic conversion of phenyl pyruvic acid, p-hydroxyphenyl pyruvic aid, indolyl pyruvic acid or 2-keto-4-(methylmercapto)-butyric acid into the corresponding L-.alpha.-aminocarboxylic acids.Type: GrantFiled: February 24, 1984Date of Patent: May 20, 1986Assignees: Degussa Aktiengesellschaft, Gesellschaft fur biotechnologisch ForschungInventors: Maria-Regina Kula, Werner Hummel, Horst Schutte, Wolfgang Leuchtenberger
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Patent number: 4562149Abstract: A yeast culture containing at least 10% by weight, based on the dry cell, of S-adenosyl methionine; and a process for producing S-adenosyl methionine, which comprises cultivating a yeast having the ability to produce S-adenosyl methionine in a liquid culture medium containing methionine to accumulate at least 10% by weight, based on the dry yeast cells, of S-adenosyl methionine in the yeast cells, separating the yeast cells from the culture medium, and thereafter obtaining S-adenosyl methionine in a stable form from the yeast cells.Type: GrantFiled: February 4, 1983Date of Patent: December 31, 1985Assignee: Nippon Zeon Co., Ltd.Inventors: Shozo Shiozaki, Hideaki Yamada, Yoshiki Tani, Sakayu Shimizu
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Patent number: 4518692Abstract: A process is described for producing alpha amino acids or derivatives thereof. The process comprises reacting an alpha-keto acid with L-aspartic acid in the presence of transaminase enzyme to produce (1) an alpha amino acid corresponding to said alpha-keto acid and (2) oxaloacetate; and decarboxylating said oxaloacetate.Type: GrantFiled: September 1, 1983Date of Patent: May 21, 1985Assignee: Genetics Institute, Inc.Inventor: J. David Rozzell
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Patent number: 4390626Abstract: An immobilized aminoacylase is prepared by bonding aminoacylase to a water-insoluble porous anion exchanger such as a porous phenolic resin, porous styrene resin, porous silica or porous glass having anion exchange groups and treating the bonded amino-acylase with a crosslinking agent such as an aliphatic dialdehyde. The porous anion exchanger preferably has a pore size of about 150.degree. to 3,000 A.degree., pore volume of about 0.3 to 1.0 m.sup.1 /g, specific surface area of about 10 to 150 m.sup.2 /g and particle size of above 0.1 to 1.2 mm. Preferred anion exchangers are trimethylammonium-introduced styrene resin and trimethylammonium-introduced silica.Type: GrantFiled: July 29, 1981Date of Patent: June 28, 1983Assignee: Tanabe Seiyaku Co., Ltd.Inventors: Ichiro Chibata, Tetsuya Tosa, Takao Mori, Motoki Fujimura
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Patent number: 4335210Abstract: L-2-oxothiazolidine-4-carboxylate, a sulfur analog of 5-oxoproline, is cleaved by the enzyme 5-oxo-L-prolinase to form cysteine, thus providing the basis for a cysteine delivery system by the addition of L-2-oxothiazolidine-4-carboxylate to base amino acid solutions or by injecting it directly into in vivo cells.Type: GrantFiled: February 11, 1981Date of Patent: June 15, 1982Assignee: Cornell Research FoundationInventors: Alton Meister, Joanne M. Williamson
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Patent number: 4237227Abstract: A process for preparing D-N-carbamoyl-.alpha.-amino acids by subjecting 5-substituted hydantoins to the action of a cultured broth, cells or treated cells of microorganisms having an ability in asymmetrically hydrolyzing the hydantoin ring in an aqueous medium of pH 7 to 10. The process is suited for the industrial manufacture of D-N-carbamoyl-.alpha.-amino acids which are useful intermediates for the preparation of medicines.Type: GrantFiled: December 21, 1977Date of Patent: December 2, 1980Assignee: Kanegafuchi Kagaku Kogyo Kabushiki KaishaInventors: Hideaki Yamada, Satomi Takahashi, Koji Yoneda
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Patent number: 4232123Abstract: A method is disclosed for making a water-soluble hydrolyzate of a keratinaceous starting material which comprises first subjecting said starting material to acid treatment at a pH of 2 or below and at an elevated temperature above 80.degree. C. to effect mild hydrolysis thereof and then enzymatically degrading said acid-treated material in an aqueous bath in the presence of urea with an alkaline proteinase having an activity optimum in a range between pH 9 and pH 13, the initial pH of the enzymatic treatment being within the pH range optimum for the enzyme employed.Type: GrantFiled: July 9, 1979Date of Patent: November 4, 1980Assignees: Firma Carl Freudenberg, R/hm GmbHInventors: Klaus Braeumer, Zdenek Eckmayer, Alexander Berg, Rolf Monsheimer, Ernst Pfleiderer
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Patent number: 4211840Abstract: D-.alpha.-amino acids are produced by contacting a 5-substituted hydantoin with an effective amount of an enzyme capable of converting the 5-substituted hydantoin to the D-.alpha.-amino acid produced by a microorganism in an aqueous medium at a pH in the range of 4 to 9, the microorganism being capable of utilizing the D-isomer of the 5-substituted hydantoin as the sole nitrogen source, but substantially incapable of utilizing the L-isomer of the 5-substituted hydantoin as the nitrogen source and the substituent of the 5-position being such that upon reaction with the enzyme, an optically active D-.alpha.-amino acid isomer is produced; and recovering the D-.alpha.-amino acid which accumulates in the aqueous medium.Type: GrantFiled: April 17, 1978Date of Patent: July 8, 1980Assignee: Ajinomoto Company, IncorporatedInventors: Shigeru Nakamori, Kenzo Yokozeki, Koji Mitsugi, Chikahiko Eguchi, Hisao Iwagami