Abstract: The present invention provides a protein having low-substrate-specific amino acid racemase activity; DNA encoding the protein; a recombinant DNA comprising the DNA; a transformant carrying the recombinant DNA; a process for producing the protein by using the transformant; and a process for producing a racemic amino acid which comprises allowing a culture of the transformant or a treated matter thereof as an enzyme source and an amino acid to be present in an aqueous medium to racemize the amino acid in the aqueous medium, and recovering the racemic amino acid from the aqueous medium.

Abstract: The present invention provides a protein having low-substrate-specific amino acid racemase activity; DNA encoding the protein; a recombinant DNA comprising the DNA; a transformant carrying the recombinant DNA; a process for producing the protein by using the transformant; and a process for producing a racemic amino acid which comprises allowing a culture of the transformant or a treated matter thereof as an enzyme source and an amino acid to be present in an aqueous medium to racemize the amino acid in the aqueous medium, and recovering the racemic amino acid from the aqueous medium.

Abstract: Bacillus subtilis var. chungkookjang, accession no. KCTC 0697BP, a salt-resistant B. subtilis variant isolated from “chungkookjang,” a traditional Korean fermented soy bean paste. This B. subtilis variant produces poly-gamma-glutamic acid (or poly-gamma-glutamate, ?-PGA), an edible, soluble, anionic, and biodegradable high molecular-weight polymer. Bacillus subtilis var. chungkookjang produces ?-PGA with a higher molecular weight than other extracellular ?-PGAs derived from general Bacillus sp. strains. Accordingly, the ?-PGA produced by Bacillus subtilis var. chungkookjang can be utilized for the development of high value-added products, such as cosmetics, absorption agents, and biodegradable plastic materials.

Abstract: The present invention relates to a surface expression vector having pgsBCA, a gene coding poly-gamma-glutamate synthetase and a method for expression of target protein at the surface of microorganism using the vector. The vector, in which foreign genes are inserted, transforms microorganisms and makes foreign proteins expressed stably on the surface of microorganisms.

Abstract: The present invention provides a protein having low-substrate-specific amino acid racemase activity; DNA encoding the protein; a recombinant DNA comprising the DNA; a transformant carrying the recombinant DNA; a process for producing the protein by using the transformant; and a process for producing a racemic amino acid which comprises allowing a culture of the transformant or a treated matter thereof as an enzyme source and an amino acid to be present in an aqueous medium to racemize the amino acid in the aqueous medium, and recovering the racemic amino acid from the aqueous medium.

Abstract: Salt-resistant Bacillus subtilis var. chungkookjang, accession no. KCTC 0697BP, separated from “chungkookjang” a traditional Korean fermented soy bean paste and its poly-gamma-glutamic acid (or poly-gamma-glutamate, g-PGA), an edible, soluble, anionic, and biodegradable high molecular-weight polymer. Bacillus subtilis var. chungkookjang produces g-PGA with a higher molecular weight than other extracellular g-PGAs derived from general Bacillus sp. strains and can be utilized for the development of high value-added products, such as cosmetics, absorption agents, and biodegradable plastic materials.

Abstract: The present invention relates to a poly-gamma-glutamate (PGA) having an ultra-high molecular weight greater than 5,000 kDa. The ultra-high molecular weight PGA according to the present invention has a mean molecular weight greater than 13,000 kDa, and more than 95% of its molecules have a molecular weight ranging from 3,000 to 15,000 kDa. Also, it can be produced by the culturing of Bacillus subtilis var. chungkookjang. The ultra-high molecular weight PGA according to the present invention shows very excellent moisture-absorbing, moisture-retaining, sustained release, mineral solubility, and water-absorbing properties, and thus, can be used as a new and high value-added material in various applications.

Abstract: Bacillus subtilis var. chungkookjang, accession no. KCTC 0697BP, a salt-resistant B. subtilis variant isolated from “chungkookjang,” a traditional Korean fermented soy bean paste. This B. subtilis variant produces poly-gamma-glutamic acid (or poly-gamma-glutamate, ?-PGA), an edible, soluble, anionic, and biodegradable high molecular-weight polymer. Bacillus subtilis var. chungkookjang produces ?-PGA with a higher molecular weight than other extracellular ?-PGAs derived from general Bacillus sp. strains. Accordingly, the ?-PGA produced by Bacillus subtilis var. chungkookjang can be utilized for the development of high value-added products, such as cosmetics, absorption agents, and biodegradable plastic materials.

Abstract: The present invention provides a protein having low-substrate-specific amino acid racemase activity; DNA encoding the protein; a recombinant DNA comprising the DNA; a transformant carrying the recombinant DNA; a process for producing the protein by using the transformant; and a process for producing a racemic amino acid which comprises allowing a culture of the transformant or a treated matter thereof as an enzyme source and an amino acid to be present in an aqueous medium to racemize the amino acid in the aqueous medium, and recovering the racemic amino acid from the aqueous medium.

Abstract: The present invention relates to a surface expression vector having pgsBCA, a gene coding poly-gamma-glutamate synthetase and a method for expression of target protein at the surface of microorganism using the vector. The vector, in which foreign genes are inserted, transforms microorganisms and makes foreign proteins expressed stably on the surface of microorganisms.

Abstract: The present invention relates to the salt-resistant Bacillus subtilis var. chungkookjang, accession no. KCTC 0697BP separated from “chungkookjang” a traditional Korean fermented soy bean paste and to its poly-gamma-glutamic acid (or poly-gamma-glutamate, &ggr;-PGA) an edible, soluble, anionic, and biodegradable high molecular-weight polymer.

Abstract: A recombinant protein capable of constituting a recombinant L-methionine .gamma.-lyase or a variant thereof, a recombinant oligomeric enzyme, preferably tetrameric enzyme, consisting of the recombinant protein, a DNA molecule encoding the same, an expression vector containing the DNA molecule, a host cell harboring the expression vector, a method of preparing the recombinant L-methionine .gamma.-lyase, and anti-tumor agent comprising the recombinant L-methionine .gamma.-lyase or a variant thereof are provided.

Abstract: A recombinant protein capable of constituting a recombinant L-methionine .gamma.-lyase or a variant thereof, a recombinant oligomeric enzyme, preferably tetrameric enzyme, consisting of the recombinant protein, a DNA molecule encoding the same, an expression vector containing the DNA molecule, a host cell harboring the expression vector, a method of preparing the recombinant L-methionine .gamma.-lyase, and anti-tumor agent comprising the recombinant L-methionine .gamma.-lyase or a variant thereof are provided.

Abstract: A process for producing L-lysine, which comprises culturing a mutant L-lysine-producing strain belonging to the genus Brevibacterium or the genus Corynebacterium and having selenalysine resistance in a nutrient medium, producing and accumulating L-lysine in the culture broth and collecting L-lysine from the culture broth.

Abstract: Leucine dehydrogenase is disclosed which retains 80% or more of the activity even after it is incubated in a buffer solution at about 70.degree. C. for 10 minutes, as compared to the activity prior to incubation. A process for producing a heat resistant leucine dehydrogenase is also disclosed. The process comprises culturing a microorganism having an optimum growth temperature of 50.degree. to 85.degree. C. and harvesting the leucine dehydrogenase from the culture and a composition of assaying for leucine aminopeptidase (LAP) comprising the heat resistant leucine dehydrogenase.The leucine dehydrogenase can be stored for a long period of time and thus very effective for investigations in biochemistry, food analysis and clinical test. Further the composition provides extremely easy assay for the LAP activity in high accuracy with good reproducibility which is an important item in clinical test.

Abstract: A process for the preparation of L-tryptophan comprises reacting indole with serine in the presence of tryptophan synthetase or tryptophanase, wherein DL-serine or D-serine is used and a serine racemizing enzyme is included in the reaction system and reacted with the serine.

Abstract: An L-lysine .alpha.-oxidase, that is, a novel L-amino acid oxidase having very high substrate-specificity to L-lysine is produced by culturing a specific microorganism belonging to Trichoderma in a medium.

Abstract: L-lysine contained in a sample can be efficiently determined by using the L-lysine .alpha.-oxidase. The preferred enzyme is an L-lysine .alpha.-oxidase, that is, a novel L-amino acid oxidase having very high substrate-specificity to L-lysine is produced by culturing a specific microorganism belonging to Trichoderma in a medium.

Abstract: Method for the production of substituted sulfur containing L-amino acids by contacting .beta.- or .gamma.-substituted amino acids in an aqueous medium containing methioninase together with the precursor of the substituent.