The present disclosure relates to a novel polypeptide having an activity of exporting 5′-inosine monophosphate, a microorganism comprising the same, a method for preparing 5′-inosine monophosphate using the same, and a method for increasing export of 5′-inosine monophosphate.

An expression system and process for the production of Diphtheria toxin polypeptides or mutated forms thereof, such as the toxoid CRM197 polypeptide, in genetically-modified E. coli with high yield is described. The system and process is based on the uncoupling of biomass growth from recombinant protein induction, i.e. using an inducer of protein production that cannot be used as a carbon source for growth by the bacteria. The use of specific components and conditions that improve protein yields are also described.

An expression system and process for the production of Diphtheria toxin polypeptides or mutated forms thereof, such as the toxoid CRM197 polypeptide, in genetically-modified E. coli with high yield is described. The system and process is based on the uncoupling of biomass growth from recombinant protein induction, i.e. using an inducer of protein production that cannot be used as a carbon source for growth by the bacteria. The use of specific components and conditions that improve protein yields are also described.

The present invention relates to a method for producing CRM197 recombinant protein in cells. The method comprises culturing a cell comprising an expression plasmid with a polynucleotide and inducing expression of the CRM197 protein.

The present invention relates to a method for producing CRM197 recombinant protein in cells. The method comprises culturing a cell comprising an expression plasmid with a polynucleotide and inducing expression of the CRM197 protein.

The present disclosure provides peptides derived from CRM197 and Tetanus toxoid that can be used to generate an immune response in an individual. The present disclosure includes isolated peptides and multimers of isolated peptides. Also provided are compositions that include the isolated peptide or the multimer. Further provided are methods, including methods for increasing the antigenicity of a compound, such as an antigen, and methods for inducing an immune response in a subject

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.

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 genetically engineered bacterium includes a genome of the Eschericia coli and a mutant encoding gene hisG* of a Corynebacterium glutamicum ATP phosphoribosyl transferase HisG on the genome, and the gene hisG* is strongly expressed to enhance activity of a key enzyme HisG for histidine synthesis. The gene hisG* has a nucleotide sequence as shown in SEQ ID NO: 1; a copy number of histidine operon genes hisDBCHAFI of the Eschericia coli is further increased on the genome to enhance a terminal synthetic route of histidine; an encoding gene lysE from an arginine/lysine transportprotein of the Corynebacterium glutamicum is further integrated to the genome and strongly expressed to promote the intracellular histidine secrete to the extracellular space; and an encoding gene rocG of glutamate dehydrogenase of Bacillus subtilis is further integrated to the genome and strongly expressed to promote generation of histidine.

A genetically engineered bacterium includes a genome of the Eschericia coli and a mutant encoding gene hisG* of a Corynebacterium glutamicum ATP phosphoribosyl transferase HisG on the genome, and the gene hisG* is strongly expressed to enhance activity of a key enzyme HisG for histidine synthesis. The gene hisG* has a nucleotide sequence as shown in SEQ ID NO: 1; a copy number of histidine operon genes hisDBCHAFI of the Eschericia coli is further increased on the genome to enhance a terminal synthetic route of histidine; an encoding gene lysE from an arginine/lysine transportprotein of the Corynebacterium glutamicum is further integrated to the genome and strongly expressed to promote the intracellular histidine secrete to the extracellular space; and an encoding gene rocG of glutamate dehydrogenase of Bacillus subtilis is further integrated to the genome and strongly expressed to promote generation of histidine.