摘要:
Disclosed herein are a microorganism strain capable of producing the L-methionine precursor O-acetyl homoserine in high yield and a method of producing O-acetyl homoserine using the same. The microorganism strain is a strain of Escherichia sp. in which an acetyl-CoA synthase gene (acs) and/or a pantothenate kinase gene (coaA) encoding a pantothenate kinase gene refractory to feedback inhibition by CoA is introduced and expressed.
摘要:
The present invention relates to a polypeptide that is modified to have homoserine O-acetyltransferase activity, and in particular, the present invention provides a modified polypeptide having homoserine O-acetyltransferase activity, in which the amino acid at position 111 of a polypeptide having homoserine succinyltransferase activity is substituted with other amino acid.
摘要:
The present invention relates to a method for increasing L-methionine productivity and organic acid productivity. More particularly, the present invention relates to a method which involves adding a mixture containing methyl mercaptan and dimethyl sulfide at a appropriate ratio to O-acetyl homoserine or O-succinyl homoserine and to an enzyme having an activity of converting methionine precursor into L-methionine, so as to perform an enzyme reaction, to thereby improve the conversion rate of L-methionine and organic acid from the L-methionine precursor, and thus increasing L-methionine yield as compared to conventional method.
摘要:
Disclosed is a strain of Escherichia sp., capable of producing O-acetyl homoserine in high yield, with the introduction and enhancement therein of the activity of: homoserine acetyl transferase, aspartokinase and homoserine dehydrogenase; and at least one enzyme selected from a group consisting of phosphoenolpyruvate carboxylase, aspartate aminotransferase and aspartate semi-aldehyde dehydrogenase. Also, a method of producing O-acetyl homoserine using the strain is provided.
摘要:
Disclosed herein are a microorganism strain capable of producing the L-methionine precursor O-acetyl homoserine in high yield and a method of producing O-acetyl homoserine using the same. The microorganism strain is a strain of Escherichia sp. in which an acetyl-CoA synthase gene (acs) and/or a pantothenate kinase gene (coA) encoding a pantothenate kinase gene refractory to feedback inhibition by CoA is introduced and expressed.
摘要:
The present invention relates to a novel protein having O-acetylhomoserine sulfhydrylase activity, a mutant protein thereof, a polynucleotide encoding the same, a recombinant vector comprising the polynucleotide, a microorganism transformed with the recombinant vector, and a method for producing methionine or acetic acid using the protein. The production method of the present invention has the advantage of producing L-methionine and acetic acid cost-effectively through having higher conversion rate and reduced reaction time compared to the existing methods, and it can minimize the amount of enzyme homogenate added when using the mutant protein, thereby easily producing L-methionine and acetic acid at high yield.
摘要:
The present invention relates to a polypeptide that is modified to have homoserine O-acetyltransferase activity, and in particular, the present invention provides a modified polypeptide having homoserine O-acetyltransferase activity, in which the amino acid at position 111 of a polypeptide having homoserine succinyltransferase activity is substituted with other amino acid.
摘要:
The present invention relates to a novel protein having O-acetylhomoserine sulfhydrylase activity, a mutant protein thereof, a polynucleotide encoding the same, a recombinant vector comprising the polynucleotide, a microorganism transformed with the recombinant vector, and a method for producing methionine or acetic acid using the protein. The production method of the present invention has the advantage of producing L-methionine and acetic acid cost-effectively through having higher conversion rate and reduced reaction time compared to the existing methods, and it can minimize the amount of enzyme homogenate added when using the mutant protein, thereby easily producing L-methionine and acetic acid at high yield.
摘要:
A method for the preparation of nicotinic acid, which includes the step of obtaining a culture solution containing quinolinic acid by incubating a microorganism having an ability to produce quinolinic acid, and the step of adding an acid to the culture solution and conducting a decarboxylation reaction.
摘要:
The present invention relates to a method for increasing L-methionine productivity and organic acid productivity. More particularly, the present invention relates to a method which involves adding a mixture containing methyl mercaptan and dimethyl sulfide at a appropriate ratio to O-acetyl homoserine or O-succinyl homoserine and to an enzyme having an activity of converting methionine precursor into L-methionine, so as to perform an enzyme reaction, to thereby improve the conversion rate of L-methionine and organic acid from the L-methionine precursor, and thus increasing L-methionine yield as compared to conventional method.