Provided is a mutant strain having improved aromatic amino acid production capability as a result of inactivation or weakening of activity of glutaminase which is expressed by glutaminase B (glsB) gene.

The present disclosure relates to a variant of cAMP receptor protein of Escherichia coli with alanine at position 35, a microorganism including the same, and a method of producing an L-amino acid using the same.

The present disclosure provides novel bacterial strains with altered expression or start codon modification of one or more RNA degradation/processing genes. The RNA degradation genes of the present disclosure are controlled by heterologous promoters. The present disclosure further describes methods for generating microbial strains comprising heterologous promoter sequences operably linked to RNA degradation/processing genes.

A transport protein coding gene, and a method for efficient production of L-tryptophan by a strain containing the gene. Specifically, by heterologous expression of ywkB gene from Bacillus subtilis on the genome of Escherichia coli, L-tryptophan production efficiency of the strain can be improved. Performing shake flask fermentation with the strain can accumulate 15.2 g/L of L-tryptophan within 24 h, which is 35% higher than a control strain.

Disclosed is a mutant strain having improved aromatic amino acid production capability due to inactivation or weakening of activity of an FMN/FAD exporter protein which is expressed by yeeO gene.

The present disclosure relates to methods for production of 4-hydroxytryptamine and derivatives thereof in a yeast cell. Herein are also disclosed methods for production of halogenated tryptophans and derivatives thereof in a cell. Herein are also disclosed methods for production of methylated tryptamine. The disclosure also provides nucleic acid constructs and cells useful for performing the present methods.

Provided are a cAMP receptor protein variant, a microorganism including the same, and a method of producing an L-amino acid using the same.

Disclosed is a mutant strain having improved aromatic amino acid production capability as a result of the inactivation or weakening of activity of asparaginase which is expressed by ansB gene.

The disclosure relates, in some aspects, to compositions and methods useful for production of nitrated aromatic molecules. The disclosure is based, in part, on whole cell systems expressing artificial fusion proteins comprising cytochrome P450 enzymes linked to reductase enzymes. In some aspects, the disclosure relates to methods of producing nitrated aromatic molecules in whole cell systems having artificial fusion proteins comprising cytochrome P450 enzymes linked to reductase enzymes.

The present invention discloses a method for modifying an amino acid attenuator, a class of amino acid attenuator mutants, engineered bacteria created on the basis of the amino acid attenuator mutants, and use of the engineered bacteria. The present invention protects a method for relieving the attenuation regulation of an amino acid operon gene, which is modification of the amino acid operon gene by: removing a gene coding for a leader peptide and an anterior reverse complementary palindromic sequence in the terminator stem-loop structure, and maintaining a posterior reverse complementary palindromic sequence in the terminator. The amino acid operon particularly can be histidine operon, tryptophan operon, phenylalanine operon, alanine operon, threonine operon and etc. The present invention can be used for the production of amino acids and derivatives thereof in fermentation by bacteria, providing a novel method for improving the production of amino acids in fermentation.