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.

Microbial consortia exert great influence over the physiology of humans, animals, plants, and ecosystems. However, difficulty in controlling their composition and population dynamics have limited their application in medicine, agriculture, biotechnology, and the environment. The approach disclosed herein provides an effective method to dynamically control population compositions in microbial consortia, which we demonstrate in the context of co-culture fermentations for chemical production. Co-culture fermentations can improve chemical production from complex biosynthetic pathways over monocultures by distributing enzymes across multiple strains, thereby reducing metabolic burden, overcoming endogenous regulatory mechanisms, or exploiting natural traits of different microbial species. However, stabilizing and optimizing microbial sub-populations for maximal chemical production remains a major obstacle in the field. An optogenetic circuit, called OptoTA, is disclosed for regulating a toxin-antitoxin system, which enables tunability of, e.g., Escherichia coli growth using only blue light. With the disclosed system, one can control population ratios of co-cultures of, e.g., E. coli and Saccharomyces cerevisiae containing different metabolic modules of biosynthetic pathways. Results reveal that intermediate light duty cycles improve chemical production by establishing optimal co-culture populations.

The disclosure is in the technical field of synthetic biology and metabolic engineering. The disclosure provides engineered viable bacteria. In particular, the disclosure provides viable bacteria with mutated outer membrane biosynthetic pathway leading to disruption of the pathway, preferably substantially lacking lipopolysaccharide (LPS, endotoxin) within the outer membrane. The disclosure further provides methods of generating viable bacteria and uses thereof. The disclosure also provides compositions and methods for inducing immune responses and for researching and developing therapeutic agents. Furthermore, the disclosure is in the technical field of fermentation of metabolically engineered microorganisms producing bioproduct or metabolite.

The present disclosure is in the technical field of synthetic biology and metabolic engineering. The disclosure provides engineered viable bacteria. In particular, the disclosure provides viable bacteria with reduced cell wall biosynthesis additionally modified for production of glycosylated product. The disclosure further provides methods of generating viable bacteria and uses thereof. Furthermore, the disclosure in the technical field of fermentation of metabolically engineered microorganisms producing glycosylated product.

Provided is a mutant UDG having improved thermal sensitivity compared to a wild-type UDG. The mutant UDG of the presently claimed subject matter having a high thermal sensitivity has no inhibitory effect on the PCR reaction and thus can be advantageously used for the development of PCR/qPCR Premix and particularly PCR diagnostic kits employing UDG which requires the use of relatively low temperature in melting and amplification steps.

Provided is a mutant UDG having improved thermal sensitivity compared to a wild-type UDG. The mutant UDG of the presently claimed subject matter having a high thermal sensitivity has no inhibitory effect on the PCR reaction and thus can be advantageously used for the development of PCR/qPCR Premix and particularly PCR diagnostic kits employing UDG which requires the use of relatively low temperature in melting and amplification steps.

The present invention provides a method for detecting and assaying Clostridium neurotoxins and identification of serotypes of botulinum neurotoxins in various food matrices and clinical samples. This method is also used for detection of BoNT inside the neuronal and epithelial cells. The method comprises detecting and assaying the presence of a Clostridium neurotoxin in a sample by: exposing the sample containing a Clostridium neurotoxin to a sample comprising a novel SNAMPXIN/SNAMP universal recombinant substrate fusion protein capable of producing a detectable FRET, following cleavage; detecting and assaying the presence of the Clostridium neurotoxin by measuring a change in the energy transfer or the luminescence signal; and detecting and assaying an electrophoretic mobility pattern of one or more cleaved protein bands or a degraded protein, using a high throughput automated system to identify the different serotypes of the Clostridium neurotoxin. SNAMPXIN/SNAMP is formed from parts of BoNT substrates SNAP-25 and VAMP.

The present invention provides a method for detecting and assaying Clostridium neurotoxins and identification of serotypes of botulinum neurotoxins in various food matrices and clinical samples. This method is also used for detection of BoNT inside the neuronal and epithelial cells. The method comprises detecting and assaying the presence of a Clostridium neurotoxin in a sample by: exposing the sample containing a Clostridium neurotoxin to a sample comprising a novel SNAMPXIN/SNAMP universal recombinant substrate fusion protein capable of producing a detectable FRET, following cleavage; detecting and assaying the presence of the Clostridium neurotoxin by measuring a change in the energy transfer or the luminescence signal; and detecting and assaying an electrophoretic mobility pattern of one or more cleaved protein bands or a degraded protein, using a high throughput automated system to identify the different serotypes of the Clostridium neurotoxin. SNAMPXIN/SNAMP is formed from parts of BoNT substrates SNAP-25 and VAMP.

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