5 results about "UV-Mutagenesis" patented technology

The present disclosure provides a mutant strain of Aspergillus niger designated MTCC 25761 on deposit with the Microbial Type Culture Collection and Gene Bank, Institute of Microbial Technology, Chandigarh, derived from parent strain Aspergillus niger ATCC 9142 through UV mutagenesis at 254 nm wavelength for 19 minutes with constant stirring The mutant strain demonstrates enhanced production capabilities for both citric acid and gluconic acid compared to the parent strain. The mutant strain exhibits enhanced metabolic performance through improved enzyme expression, substrate utilization efficiency, and regulatory control mechanisms. Gluconic acid production is 1.37-fold higher (164.045 g / L) and citric acid production is 1.29-fold higher (0.506 g / L) than the parent strain.

The invention belongs to the technical field of genetically engineered bacteria, and particularly discloses apramycin genetically engineered bacteria with genetic stability as well as a construction method and application of the apramycin genetically engineered bacteria. The construction method comprises the following steps: by taking a plasmid containing an xylE gene and a tsnR gene as a template, obtaining a linearized vector skeleton without a promoter; the method comprises the following steps: inserting a streptomyces indicus promoter sequence into a linearized vector skeleton to enable the promoter to be located at the upstream of an xylE gene and a tsnR gene, and constructing a double-reporter gene expression vector; transferring the expression vector into streptomyces through conjugation to obtain a conjugate; the genetically stable strain is obtained through ultraviolet mutagenesis in combination with catechol chromogenic screening. The biological value is increased by more than 40% compared with that of an original strain, the value retention rate of 94.5% or above is kept in continuous 10 generations of long-term passage experiments, and a powerful technical support is provided for industrial stable production of anti-mycoplasma active substances.

The application discloses an escherichia coli zjut-mhol and application thereof in production of heme oxygenase-1, and a gene of mouse-derived HO-1 is synthesized and cloned by using a preferred codon optimization method, a gene recombinant escherichia coli capable of producing HO-1 is constructed, and a mutant strain with high enzyme activity and stable passage is obtained through ultraviolet mutagenesis, and the mutant strain can be applied to preparation of HO-1. The strain is cultured for enzyme production, and the bacterial body with intracellular active HO-1 is obtained, and the enzyme production activity is 122 U / g according to the mass of the dry bacterial body. The HO-1 freeze-dried powder is separated from the bacterial body, and the enzyme activity of the freeze-dried powder is 91.8 U / g.

Disclosed herein is a UV mutagenesis produced new Streptomyces spororaveus strain SC263 that exhibits an increased thermostability of the antibiotic produced, which shows antibiotic activity against bacteria and fungi. Also provided are the antibiotic produced by SC263 and a composition thereof for treatment of bacterial and fungal infections. The antibiotic has a very high molecular weight, which is suitable for topical administration.

The invention belongs to the technical field of biological fermentation, and particularly relates to Wickerham Schiff's yeast with high yield of triacetyl phytosphingosine and application of the Wickerham Schiff's yeast. The strain is Wickerhamomyces ciferrii DB38MQ9, is preserved in the China Center for Type Culture Collection, and has the preservation number of CCTCC (China Center for Type Culture Collection) M20251536. The strain is obtained by performing ARTP-UV mutagenesis and screening on an initial strain of Wickerham Schiff's yeast for producing tetra-acetyl phytosphingosine, the fermentation level of the tetra-acetyl phytosphingosine in fermentation liquor can be effectively improved, the content of the tetra-acetyl phytosphingosine in the fermentation liquor of the strain can reach nearly 30g / L in 100L tank fermentation, and the yield of the tetra-acetyl phytosphingosine can be greatly improved. Not only is the subsequent purification process of the triacetyl phytosphingosine simplified, but also the method has certain application value and guiding significance for reducing the production cost of the phytosphingosine and improving the productivity.