The present invention relates to genetically modified bacteria and methods of optimizing genetically modified bacteria for the production of a metabolite.

The present invention relates to genetically modified bacteria and methods of optimizing genetically modified bacteria for the production of a metabolite.

The invention relates to a method for the protein enrichment of a heterotrophically cultured microalga, the microalga being of the genus Chlorella, even more particularly Chlorella protothecoides, characterized in that it comprises: a first step directed toward limiting the ammonium supply so as to obtain a microalgal biomass with a protein content of less than 50% expressed as N.6.25, preferably less than 30%, more preferentially between 20 and 25%; a second step in which the ammonium supply in the fermentation medium is increased so as to obtain a protein content of greater than 50%, preferably greater than 60%, more preferentially greater than 65%.

The invention relates to a method for the protein enrichment of a heterotrophically cultured microalga, the microalga being of the genus Chlorella, even more particularly Chlorella protothecoides, characterized in that it comprises: a first step directed toward limiting the ammonium supply so as to obtain a microalgal biomass with a protein content of less than 50% expressed as N.6.25, preferably less than 30%, more preferentially between 20 and 25%; a second step in which the ammonium supply in the fermentation medium is increased so as to obtain a protein content of greater than 50%, preferably greater than 60%, more preferentially greater than 65%.

The present disclosure relates to a microorganism having increased glycine productivity and a method for producing a fermented composition using the microorganism, and more specifically, to a microorganism of the genus Corynebacterium having increased glycine productivity due to the introduction of a mutation in HisG, a method for preparing a fermented composition comprising glycine and glutamic acid using the microorganism of the genus Corynebacterium, and the fermented composition.

The present disclosure relates to a microorganism having increased glycine productivity and a method for producing a fermented composition using the microorganism, and more specifically, to a microorganism of the genus Corynebacterium having increased glycine productivity due to the introduction of a mutation in HisG, a method for preparing a fermented composition comprising glycine and glutamic acid using the microorganism of the genus Corynebacterium, and the fermented composition.

The present invention belongs to the bioengineering field, and relates to a method for fermentation production of L-theanine by using an Escherichia coli genetically engineered bacterium. The engineered bacterium is obtained by serving a strain as an original strain, wherein the strain is obtained after performing a single copy of T7RNAP, a dual copy of gmas, xylR knockout, and sucCD knockout on an Escherichia coli W3110 genome, and by integrating genes xfp, pta, acs, gltA, and ppc, and knocking out ackA on the genome. The present invention has a high yield, and stable production performance; after 20-25 h, L-theanine has a titer of 75-80 g/L, and the yield is up to 52-55%. The fermentation broth is purified by membrane separation in combination with a cation-anion resin series technique. Moreover, the one-step crystallization yield is 72.3% and the L-theanine final product has a purity of 99%.

The present invention belongs to the bioengineering field, and relates to a method for fermentation production of L-theanine by using an Escherichia coli genetically engineered bacterium. The engineered bacterium is obtained by serving a strain as an original strain, wherein the strain is obtained after performing a single copy of T7RNAP, a dual copy of gmas, xylR knockout, and sucCD knockout on an Escherichia coli W3110 genome, and by integrating genes xfp, pta, acs, gltA, and ppc, and knocking out ackA on the genome. The present invention has a high yield, and stable production performance; after 20-25 h, L-theanine has a titer of 75-80 g/L, and the yield is up to 52-55%. The fermentation broth is purified by membrane separation in combination with a cation-anion resin series technique. Moreover, the one-step crystallization yield is 72.3% and the L-theanine final product has a purity of 99%.

The present invention relates to a Corynebacterium glutamicum mutant strain having increased L-glutamic acid productivity, a method for constructing the same, and a method of producing L-glutamic acid using the same. The Corynebacterium glutamicum mutant strain is a strain into which a mechanosensitive ion channel gene derived from a Corynebacterium sp. strain has been introduced, and thus it can produce L-glutamic acid in an improved yield due to enhancement of glutamic acid release. Therefore, when the mutant strain is used, it is possible to more effectively produce L-glutamic acid.

The present invention provides a method for producing L-amino acids such as L-amino acids belonging to the glutamate family by fermentation using a bacterium of the family Enterobacteriaceae, particularly a bacterium belonging to the genus Escherichia, which has been modified to disrupt the putrescine degradation pathway by, for example, inactivation of one gene or several genes from the puuADRCBE gene cluster.