86 results about "Microbial genetics" patented technology

The invention discloses a construction method and application of a Saccharomyces cerevisiae gsh1 deleted mutant strain. The method is performed according to the description in the document (Yeast, 1998, 14:953-962), including designing of primers and transformation of knockout segment according to the principle of homologous recombination and gene knockout of Saccharomyces cerevisiae gene. The method is a conventional method for gene knockout in the Saccharomyces cerevisiae at present. The method specifically comprises the following steps: designing primers (forward primer P1 and reverse primer P2) according to the gene sequence of Saccharomyces cerevisiae gsh1; carrying out PCR (polymerase chain reaction) amplification on the plasmid pFA6a-Kan MX6 by using the forward primer P1 and the reverse primer P2 to obtain a knockout segment containing forward and reverse sequences of the Saccharomyces cerevisiae gsh1 gene; and introducing the knockout segment into a Saccharomyces cerevisiae BY47421 strain cell by a lithium acetate / PEG (polyethylene glycol) transformation method, and screening to obtain the Saccharomyces cerevisiae DELTAgsh1 mutant strain YJL101C. The Saccharomyces cerevisiae cell DELTAgsh1 mutant strain is constructed by a microbial genetic method, and the cytotoxicity of cadmium chloride or any other heavy metal is detected by using the mutant strain, thereby enhancing the cytotoxicity detection sensitivity. The method is easy to implement and simple to operate.

The invention relates to a construction strategy and a construction process of an unmarked lysobacter enzymogenes engineering strain capable of preventing plant bacteriosis, and belongs to the field of microbial genetic engineering. An excellent exogenous gene aiiA is directionally integrated onto a chromosome, and any marked genes are not brought into the unmarked lysobacter enzymogenes engineering strain. A quorum-sensing system for plant pathogenic bacteria can be efficiently damaged by the engineering strain, pathogenicity of the pathogenic bacteria on a host plant (Chinese cabbage) is remarkably reduced, and biological prevention of the plant bacteriosis is realized.

The present invention relates to an efficient and cost effective method of preventing growth of genetic transformant bacteria Agrobacterium tumefaciens after transformation in plants by using tea leaf extract as a bactericide, wherein said method leads to elimination of common problem of polyphenol oxidation during transformation and thereby helps maintain regeneration potential in explants and also helps in increased transformation efficacy

The invention relates to the technical field of microbial genetic engineering, and discloses saccharomyces cerevisiae for high-yield production of hydroxytyrosol and a construction method thereof. The saccharomyces cerevisiae for high-yield production of hydroxytyrosol expresses HpaB and HpaC with specific sources on the basis of saccharomyces cerevisiae capable of synthesizing hydroxytyrosol, thereby realizing the preparation and high yield of hydroxytyrosol. The invention mainly selects 4-hydroxyphenylacetic acid-3-hydroxylase derived from pseudomonas aeruginosa, and combines with riboflavin oxidoreductase with other specific sources to transfer the 4-hydroxyphenylacetic acid-3-hydroxylase into saccharomyces cerevisiae chassis cells capable of producing hydroxytyrosol, thereby realizing the improvement of the yield of hydroxytyrosol; and on the basis, various modifications are further carried out, so that the yield of hydroxytyrosol of the saccharomyces cerevisiae is up to 1120mg / L, and a new way is provided for the efficient fermentation production of hydroxytyrosol by microorganisms.

The invention discloses a construction method and application of a Saccharomyces cerevisiae gsh1 deleted mutant strain. The method is performed according to the description in the document (Yeast, 1998, 14:953-962), including designing of primers and transformation of knockout segment according to the principle of homologous recombination and gene knockout of Saccharomyces cerevisiae gene. The method is a conventional method for gene knockout in the Saccharomyces cerevisiae at present. The method specifically comprises the following steps: designing primers (forward primer P1 and reverse primer P2) according to the gene sequence of Saccharomyces cerevisiae gsh1; carrying out PCR (polymerase chain reaction) amplification on the plasmid pFA6a-Kan MX6 by using the forward primer P1 and the reverse primer P2 to obtain a knockout segment containing forward and reverse sequences of the Saccharomyces cerevisiae gsh1 gene; and introducing the knockout segment into a Saccharomyces cerevisiae BY47421 strain cell by a lithium acetate / PEG (polyethylene glycol) transformation method, and screening to obtain the Saccharomyces cerevisiae DELTAgsh1 mutant strain YJL101C. The Saccharomyces cerevisiae cell DELTAgsh1 mutant strain is constructed by a microbial genetic method, and the cytotoxicity of cadmium chloride or any other heavy metal is detected by using the mutant strain, thereby enhancing the cytotoxicity detection sensitivity. The method is easy to implement and simple to operate.

The invention discloses a method for preparing microorganism competent cells by using constant-pressure room-temperature plasmas, and belongs to the application of a plasma technology in a biological technical field. According to the basic principle provided by the invention, energetic ions and charged particles in the plasmas are used for interacting with proteins and genetic materials in the microorganism cells, so as to finally cause the property change of the cells. Therefore, the cells are at a physiological status which is the most suitable for capturing and containing external DNA. The method provided by the invention uses the constant-pressure room-temperature plasmas with a liquid circulation system, and uses helium as a plasma discharging gas to take effect on the microorganism cells, so that the competent cells can be efficiently and conveniently prepared. The method is efficient, fast, safe and convenient, and can be widely used for as a novel experimental technique in fields including microbial genetics, molecular genetics and genetic engineering,.

The invention discloses a method for genetic transformation of a cell. An ultrasonic transformation device is utilized, and the following parameters are set for the ultrasonic transformation device: 1) the ultrasonic transmitting frequency is 0.1 to 1,000 KHz; and 2) the ultrasonic output power is 0.01 to 1,000Watt / cm<2>; and under the conditions, a biomacromolecule to be transformed is transformed into microbial cells, microalgae cells and animal and plant cells. The invention also provides the ultrasonic transformation device for implementing the method. The method and the device can be used for microbial genetic transformation, mass and energy transfer among cells and regular transformation of nucleic acid, protein, polysaccharide and medicament in a bioreactor.

The invention belongs to the technical field of recombinant microbial genetic engineering, particularly relates to a construction method of a recombinant bacillus subtilis strain, and further relatesto application of the recombinant bacillus subtilis strain, in particular to the application thereof to synthesis of acety-lglucosamine. The construction method of a recombinant bacillus subtilis comprises the steps as follows: using bacillus subtilis BSGNK-PxylA-glmS-P43-GNA1 as a starting strain, knocking out KHG / KDPG aldolase gene kdgA, and obtaining the recombinant bacillus subtilis strain. The recombinant bacillus subtilis, provided by the invention, can efficiently utilize glucose to synthesize the acety-lglucosamine, and the fermentation yield of shake flask can reach 7.34 g / L, which is11.84% higher than that before the knockout, thereby laying a foundation for further transforming the bacillus subtilis to produce glucosamine through metabolic engineering.