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Yanggu, South Korea

Seo J.-H.,Seoul National University | Kyung D.,Seoul National University | Kyung D.,SK Holdings Co. | Joo K.,Korea Institute of Advanced Study | And 2 more authors.
Biotechnology and Bioengineering | Year: 2011

The half reactions of ω-aminotransferase (ω-AT) from Vibrio fluvialis JS17 (ω-ATVf) were carried out using purified pyridoxal 5'-phosphate-enzyme (PLP-Enz) and pyridoxamine 5'-phosphate-enzyme (PMP-Enz) complexes to investigate the relative activities of substrates. In the reaction generating PMP-Enz from PLP-Enz using L-alanine as an amine donor, L-alanine showed about 70% of the initial reaction rate of (S)-α-methylbenzylamine ((S)-α-MBA). However, in the subsequent half reaction recycling PLP-Enz from PMP-Enz using acetophenone as an amine acceptor, acetophenone showed nearly negligible reactivity compared to pyruvate. These results indicate that the main bottleneck in the asymmetric synthesis of (S)-α-MBA lies not in the amination of PLP by alanine, but in the amination of acetophenone by PMP-Enz, where conformational restraints of the enzyme structure is likely to be the main reason for limiting the amine group transfer from PMP-Enz to acetophenone. Based upon those half reaction experiments using the two amino acceptors of different activity, it appears that the relative activities of the two amine donors and the two acceptors involved in the ω-AT reactions can roughly determine the asymmetric synthesis yield of the target chiral amine compound. Predicted conversion yields of several target chiral amines were calculated and compared with the experimental conversion yields. Approximately, a positive linear correlation (Pearson's correlation coefficient = 0.92) was observed between the calculated values and the experimental conversion yields. To overcome the low (S)-α-MBA productivity of ω-ATVf caused by the possible disadvantageous structural constraints for acetophenone, new ω-ATs showing higher affinity to benzene ring of acetophenone than ω-ATVf were computationally screened using comparative modeling and protein-ligand docking. ω-ATs from Streptomyces avermitilis MA-4680 (SAV2612) and Agrobacterium tumefaciens str. C58 (Atu4761) were selected, and the two screened ω-ATs showed higher asymmetric synthesis reaction rate of (S)-α-MBA and lower (S)-α-MBA degradation reaction rate than ω-ATVf. To verify the higher conversion yield of the variants of ω-ATs, the reaction with 50 mM acetophenone and 50 mM alanine was performed with coupling of lactate dehydrogenase and two-phase reaction system. SAV2612 and Atu4761 showed 70% and 59% enhanced yield in the synthesis of (S)-α-MBA compared to that of ω-ATVf, respectively. © 2010 Wiley Periodicals, Inc. Source


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Sk Holdings Co. | Date: 2016-06-08

Gas for processing semiconductor; detergents for industrial use; detergents for use in manufacturing processes; etchants for use in the manufacture of semiconductors; detergents for industrial use as part of manufacturing operations; perfluorinated chemical compounds prepared synthetically for use in manufacture; silanes for the manufacture of semiconductor and solar batteries; chemical source material for the deposition of thin films upon semiconductor wafers for the manufacture of semiconductors; chemicals for use in the manufacture of solar cells; chlorides; chlorofluorocarbons; carbon fluorochloride; etching solutions (acids); caustics for industrial purposes; corrosive preparations; acids; inorganic acid.


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Sk Holdings Co. | Date: 2015-12-07

pharmaceutical and veterinary preparations for treatment of central nervous system diseases, cancer and metabolic diseases; sanitary preparations for medical use; biological preparations for medical purposes, namely, for the treatment of central nervous system diseases, cancer and metabolic diseases; biochemical preparations for medical purposes, namely, for the treatment of central nervous system diseases, cancer and metabolic diseases; chemical preparations for pharmaceutical purposes, namely, for the treatment of central nervous system diseases, cancer and metabolic diseases; medical preparation of trace elements for human and animal use, namely, for the treatment of central nervous system diseases, cancer and metabolic diseases; ferments for pharmaceutical purposes; biotechnological preparations for medical purposes, namely, for the treatment of central nervous system diseases, cancer and metabolic diseases; blood solvent; chemical preparations for medicinal purposes, namely, for the treatment of central nervous system diseases, cancer and metabolic diseases; chemical preparations for medical or veterinary purposes, namely, for the treatment of central nervous system diseases, cancer and metabolic diseases; chemical preparations for sanitary use; pharmaceutical preparations for immunity adjustment; vitamin preparations; vaccines; dietary supplements; therapeutic drugs and agents for the treatment of central nervous system diseases, cancer and metabolic diseases; chemico-pharmaceutical preparations for the treatment of central nervous system diseases, cancer and metabolic diseases; bacteriological preparations for medical and veterinary use.


Sk

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Sk Holdings Co. | Date: 2015-09-25

Sanitary preparations for medical use; chemical preparations for sanitary use; dietary supplements; bacteriological preparations for medical and veterinary use; pharmaceutical and veterinary preparations for treatment of central nervous system diseases, cancer and metabolic diseases; biochemical preparations for medical purposes, namely for the treatment of central nervous system diseases, cancer and metabolic diseases; chemical preparations for pharmaceutical purposes namely for the treatment of central nervous system diseases, cancer and metabolic diseases; biotechnological preparations for medical purposes, namely for the treatment of central nervous system diseases, cancer and metabolic diseases; chemical preparations for medicinal purposes, namely for the treatment of central nervous system diseases, cancer and metabolic diseases; chemical preparations for medical or veterinary purposes, namely for the treatment of central nervous system diseases, cancer and metabolic diseases; therapeutic drugs and agents for the treatment of central nervous system diseases, cancer and metabolic diseases; chemico-pharmaceutical preparations for the treatment of central nervous system diseases, cancer and metabolic diseases.


Trademark
Sk Holdings Co. | Date: 2015-09-30

Pharmaceutical and veterinary preparations; dietetic food and substances for medical or veterinary purposes; sanitary preparations for medical use; biological preparations for medical purposes; biochemical preparations for medical purposes; chemical preparations for pharmaceutical purposes; preparations of trace elements for human and animal use; ferments for pharmaceutical purposes; biotechnological preparations for medical purposes; blood solvent; chemical preparations for medicinal purposes; chemical preparations for medical or veterinary purposes; chemical preparations for sanitary use; pharmaceutical preparations for immunity adjustment; vitamin preparations; vaccines; dietary supplements; therapeutic drugs and agents; chemico-pharmaceutical preparations; bacteriological preparations for medical and veterinary use.

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