摘要:
Escherichia. coli mutants which can be used for the synthesis of D-amino acids, and to such a process. The mutants are distinguished by deficiencies in particular enzymes which break down D-amino acids and include those which produce D-amino acids via the carbamoylase/hydantoinase route.
摘要:
The present invention relates to specific E. coli mutants which can be used for the synthesis of D-amino acids, and to such a process. The mutants are distinguished by deficiencies in particular enzymes which break down D-amino acids.
摘要:
The present invention relates to a screening process for hydantoin racemases and to novel hydantoin racemases, to the nucleic acid sequences coding therefor and to a proces for mutagenesis. Hydantoin racemases are of interest in connection with the production of enantiomerically enriched amino acids from racemic hydantoins.
摘要:
The present invention relates to a screening process for hydantoin racemases and to novel hydantoin racemases, to the nucleic acid sequences coding therefor and to a proces for mutagenesis.Hydantoin racemases are of interest in connection with the production of enantiomerically enriched amino acids from racemic hydantoins.
摘要:
The present invention relates to the preparation of compounds of formula (I): from the corresponding hydantoins by means of an enzymatic process. The L-compound is preferably formed.
摘要:
A process for the preparation of an enantiomerically enriched amine, is performed by a) cleaving a racemic mixture of a reaction product of i) a chiral amine and ii) an acyl donor, in the presence of a hydrolase, to obtain a mixture of an enantiomerically enriched amide and an enantiomerically enriched amine; or b) reacting an amine with an acyl donor, in the presence of a hydrolase, to obtain a mixture of an enantiomerically enriched amide and an enantiomerically enriched amine; and c) separating the enantiomerically enriched amide from the enantiomerically enriched amine, wherein the acyl donor is a sulphonylacetic acid ester. The process (1) leads to high enantioselectivities, and (2) high reactivities, (3) is based on an acyl donor accessible in a simple manner, (4) is suitable for a large number of very different substrates and/or (5) is suitable for carrying out at high substrate concentrations.
摘要:
The present invention relates to a process for the preparation of optically active alcohols from ketones with the aid of whole-cell catalysts comprising an alcohol dehydrogenase and also an enzyme capable of cofactor regeneration, a substrate concentration of at least 500 mM of ketone being provided for the conversion and the conversion being carried out without the addition of an “external” cofactor.
摘要:
Hydantoinase enzymes which are mutants of a previously isolated hydantoinase having the amino acid SEQ. ID. NO. 2. The mutants include amino acid substitutions at positions 95, 154, 180, 251 and/or 255 of the wild type hydantoinase (SEQ. ID. NO. 2). The mutant hydantoinases, like the parent hydantoinase, are used in the production of optically pure amino acids.
摘要翻译:乙内酰脲酶,其是具有氨基酸SEQ ID NO:1的先前分离的乙内酰脲酶的突变体。 ID。 没有。 突变体包括野生型乙内酰脲酶(SEQ ID NO:2)的95,54,180,251和/或255位的氨基酸取代。 突变的乙内酰脲酶,如亲水乙内酰脲酶,用于生产光学纯氨基酸。
摘要:
A process for the preparation of an enantiomerically enriched amine, is performed by a) cleaving a racemic mixture of a reaction product of i) a chiral amine and ii) an acyl donor, in the presence of a hydrolase, to obtain a mixture of an enantiomerically enriched amide and an enantiomerically enriched amine; or b) reacting an amine with an acyl donor, in the presence of a hydrolase, to obtain a mixture of an enantiomerically enriched amide and an enantiomerically enriched amine; and c) separating the enantiomerically enriched amide from the enantiomerically enriched amine, wherein the acyl donor is a sulphonylacetic acid ester. The process (1) leads to high enantioselectivities, and (2) high reactivities, (3) is based on an acyl donor accessible in a simple manner, (4) is suitable for a large number of very different substrates and/or (5) is suitable for carrying out at high substrate concentrations.
摘要:
The present invention relates to a new D-carbamoylase and the gene sequences which code for this from the organism Arthrobacter crystallopoietes DSM 20117. Plasmids, vectors, microorganisms, particular primers and specific possible uses of the enzymes according to the invention are also mentioned. The invention moreover describes a new process for the discovery of enzymes which can be employed in a process for the preparation of D-amino acids starting from 5′-substituted hydantoins.