10 results about "Promoter mutation" patented technology

The invention discloses a promoter mutant and an application of the promoter mutant in production of isoleucine. The invention provides a DNA molecule which is any one of the following: A1) a DNA molecule with a nucleotide sequence as shown in SEQ ID No.2; a2) is a variant which is obtained by substitution, deletion or addition of one or more nucleotides at other positions except the 66th nucleotide in the nucleotide sequence as shown in SEQ ID No.2, and the obtained DNA molecule has the same or enhanced promoter activity. Experiments prove that a series of promoter mutants with different strength and regulation characteristics are constructed to replace natural promoters, so that the transcriptional level of a target gene in a key period of fermentation is accurately improved, and the yield of the target gene is increased. The promoter engineering strategy provides a new direction for improving the production performance of industrial microorganisms by optimizing endogenous stress-resistant elements.

The application discloses a ClHAK8 gene promoter variation site related to watermelon salt tolerance and application thereof, and relates to the technical field of biology.The ClHAK8 gene promoter variation site is located at the position of-1534 to-1529 bp in the ClHAK8 gene promoter region; and the nucleotide sequence of the ClHAK8 gene is shown as SEQ ID NO.1.It is first clarified in the application that the presence or absence of the W-box element (TTGACC) at the position of-1534 to-1529 bp in the upstream promoter region of the watermelon ClHAK8 gene is a core molecular switch for regulating watermelon salt tolerance.The application clarifies the molecular mechanism of the variation of the promoter cis-element for affecting the salt stress response of watermelon by regulating the expression of a potassium transport gene, perfects the salt tolerance regulation network of watermelon, and provides a stable and practical detection tool for the molecular marker assisted breeding of salt-tolerant watermelon.

This invention provides a lacUV5(26) mutant and a high-yield strain of lysostaphin, belonging to the field of biotechnology. lacUV5 A promoter mutant, the nucleotide sequence of which is SEQ ID NO.1; an Escherichia coli Nissle 1917 expression system, comprising: expression strain EcN△P, plasmid pSC101- lacUV5( 26 )‑T7RNAP、 Expression vector pET-22b(+); plasmid pSC101- lacUV5( 26 ）‑ T7RNAP The nucleotide sequence is SEQ ID NO.2; the expression strain EcN△P is an EcN with plasmids pMUT1 and pMUT2 knocked out. Using this E. coli Nissle 1917 expression system to express lysostaphin can increase the expression level of lysostaphin in the strain.

The invention relates to a rice OsACC gene promoter mutant resistant to fluazifop-p-butyl or clethodim and application of the rice OsACC gene promoter mutant resistant to fluazifop-p-butyl or clethodim. The rice OsACC gene mutant is a deletion mutant; the sequence of the nucleic acid before mutation is deleted is as shown in SEQ ID No. 1; the length of the sequence of the deleted nucleic acid is 38-97 bp, A in the initiation codon ATG of the OsACC gene is 0 site, the deleted nucleic acid occurs in the 305-209 sites of the upstream of the initiation codon ATG, and at least the basic groups of the 305-268 sites of the upstream of the initiation codon ATG are deleted; the length of the sequence of the deleted nucleic acid is 63-97 bp, the deleted nucleic acid occurs in the 305-209 sites upstream of the initiation codon ATG, and at least the bases at the 305-243 sites upstream of the initiation codon ATG are deleted.

The invention belongs to the technical field of gene engineering, and relates to a promoter mutant, a method for producing L-isoleucine by using the promoter mutant and application of the promoter mutant. The invention provides a promoter mutant, and a DNA (deoxyribonucleic acid) molecule of the promoter mutant is any one of the following: A1) a DNA molecule with a nucleotide sequence as shown in SEQ ID No.2; a2) a DNA molecule which is obtained by carrying out conservative replacement on a plurality of nucleotides except the 152nd site of the SEQ ID No.2 and has the homology of 95% or above and the promoter function. A series of promoter mutants with different strength and regulation characteristics are constructed to replace natural promoters of the promoter mutants, and results show that in high-density fermentation of engineering strains, the strains show higher environmental tolerance and longer stable production period, and the yield and production efficiency of the L-isoleucine are remarkably improved.

The invention relates to a bacillus subtilis time sequence type promoter and application thereof, and aims to provide a group of time sequence type promoter mutants which have higher transcriptional activity in four different growth periods of bacillus subtilis and keep the dependency characteristic of the growth periods through construction and screening of a promoter random mutation library. The method comprises the following steps: by taking pHT plasmids as a skeleton, placing four dependent promoters in different growth periods at the upstream of a reporter gene, constructing four plasmid vectors of pHT-Phag, PLytR, PspoVG and PmmgA-sfGFP, constructing a random mutation library for the promoters, performing high-throughput preliminary screening on the library by using a flow cytometry screening technology, performing secondary screening by using 96-well plate culture, and performing high-throughput screening on the screened library by using a high-throughput screening technology. Finally, mutants with improved transcriptional activity are successfully obtained, and the dominant mutants are applied to recombinant expression of proteins, so that technical support and reference are provided for enriching expression elements in bacillus subtilis.

The application discloses a Bacillus subtilis promoter mutant and application, and belongs to the field of biotechnology and genetic engineering technology. The application aims to improve the activity of the Bacillus subtilis promoter. The application provides a Bacillus subtilis promoter mutant, wherein the mutant is obtained by performing single-base or multi-base mutation on a promoter gene shown in SEQ ID NO. 1. The high-activity promoter Psrf mutant greatly improves enzyme activity when mediating alpha-amylase expression, and has superior performance in a heterologous expression system, has certain universality, and has a wide application prospect in the industrial production field.

The invention discloses a constitutive promoter library and application, and relates to a construction method of a bacillus methylophilus promoter library, polynucleotide with promoter activity, a promoter mutant library containing the polynucleotide with the promoter activity, a transcription expression cassette, a recombinant expression vector and a recombinant host cell. And a method for producing a target compound. The invention firstly provides the construction method of the bacillus methylolmethane promoter library, a series of promoter mutants can be obtained through the method, the promoter mutants cover a wide expression intensity range and are wide in universality, and abundant promoter elements are provided for modification of target genes.

The invention relates to a rice OsACC gene promoter mutant and application thereof. The rice OsACC gene mutant is a deletion mutant; wherein the deletion mutation occurs in the promoter of the rice OsACC gene, and the sequence of the nucleic acid before the deletion mutation is shown as SEQ ID No.1; the length of the sequence of the deleted nucleic acid is 14 bp to 106 bp, A in an initiation codon ATG of the OsACC gene is 0 site, the deleted nucleic acid occurs in 251 to 146 sites of the upstream of the initiation codon ATG, and at least basic groups of 200 to 187 sites of the upstream of the initiation codon ATG are deleted. The mutant can enable rice to obtain resistance to at least one of herbicide fluazifop-p-butyl, haloxyfop-R-methyl and clethodim.

The application belongs to the technical field of biological medicine, and particularly relates to a SaRNA subgenomic promoter mutant, a mutation method and application thereof. The application obtains a series of promoter mutants with significantly improved expression efficiency by site-directed mutagenesis on the SaRNA subgenomic promoter. Compared with the wild-type promoter, the mutant significantly enhances the expression level of the downstream gene at the cell level and in the animal body. The SaRNA constructed based on the mutant can achieve the same or stronger protein expression effect at a lower dose, and has a wide application prospect in the fields of infectious disease prevention, tumor immunotherapy and protein replacement therapy.