36 results about "Streptomyces roseosporus" patented technology

The present invention relates to an improved process for the production of Daptomycin by fermentation with Streptomyces roseosporus, in the presence of n-decanal or Cuphea oil as sources of the n-decanoyl side chain. These reagents allow to reduce toxicity effects on the bacteria and to avoid the use of solvents in the feeding solution.

The invention discloses a streptomycete and a method for producing daptomycin by using the streptomycete. The strain is preserved in the General Microorganism Center of China Microbial Strain Preservation Management Committee, and the preservation number is CGMCC No.5956. In the present invention, Streptomyces CGMCC No.5956 is cultivated under suitable fermentation conditions by adding capric acid and capric aldehyde composition as a precursor Fermentative production of daptomycin. By adopting the method for producing daptomycin by Streptomyces described in the present invention, the titer of the target product daptomycin is high, the resource utilization rate is high, and the production cost is low, which is beneficial to industrial scale production.

The invention provides a construction method and use of Streptomyces roseosporus gene engineering bacteria. The construction method comprises: cloning upstream and downstream accessory key genes dptE, dptF, dptG, dptH, dptI and dptJ of a nonribosomal peptide synthetases (NRPS) gene in a daptomycin gene cluster; and constructing recombinant plasmids by using an Escherichia coli-Streptomyces shuttle expression vector. The recombinant plasmids are transferred into Escherichia coli ET12567 to culture the ET12567 and the Streptomyces roseosporus together, the Streptomyces roseosporus is transformed by a combined transfer method, a transformant is screened by brulamycin resistance and polymerase chain reaction (PCR) is performed for further confirmation. The Streptomyces roseosporus gene engineering bacteria constructed by the invention can be directly used in the industrial production of daptomycin and can improve yield and reduce cost.

The invention provides a method for producing daptomycin by fermentation, characterized by in the fermental cultivation process of Streptomyces roseosporus, adding an aseptic composite amino acid solution in the fermentation solution. Compared with a process without adding the composite amino acid, the method allows the fermentation unit of daptomycin to increase by more than 10 %, the impurity ingredients of products are not changed obviously, simultaneously, the method has the advantages of simple production operation, low requirement of devices, and low cost, and is suitable for industrial production.

The present invention relates to a Streptomyces roseosporus (Streptomyces roseosporus) L31 with high yield of daptomycin, which fuses two enzymes (DptE and DptF) in the initial reaction of the synthesis pathway of daptomycin, and directional transforms tryptophan The production of daptomycin in this strain was increased by 140% compared with the original strain (WT).

The invention discloses a high-yield daptomycin strain and a method for preparing daptomycin by its fermentation method, belonging to the technical field of biochemical industry. The present invention uses Streptomyces roseosporus as the starting bacterium, and obtains a high-yielding mutagenic strain WKL-126 through protoplast fusion and gene recombination technology, which has been registered in the General Microorganism Center of China Microbiological Culture Collection Management Committee ( CGMCC), the preservation number is: 3731; the present invention also discloses a method for preparing daptomycin by using the strain, and compared with the existing method, the fermentation unit of the method reaches more than 2000 mg / L.

The invention discloses a screening method for breeding Streptomyces roseosporus strains producing Daptomycin and the obtained strains. The screening method comprises the following steps of: 1) coating bacteria liquid of wild Streptomyces roseosporus or mutant strains thereof subjected to mutagenesis on a solid panel containing streptomycin and / or Daptomycin, and culturing to obtain streptomycin and / or Daptomycin tolerant Streptomyces roseosporus; and 2) respectively selecting a single colony of the streptomycin and / or Daptomycin tolerant Streptomyces roseosporus for shake flask fermentation, detecting the Daptomycin content in fermented materials, and selecting strains with the Daptomycin content higher than that of starting strains. The screening method has the advantages of directivity, intuition, simpleness, quickness, high efficiency, great reduction of workload, and acceleration of strain breeding process. The Daptomycin fermentation unit of the screened Streptomyces roseosporus strains is obviously improved, which can be improved by more than 5 times to the maximum.

The invention relates to a batch type feed-batch fermentation method for streptomyces roseosporus to produce Daptomycin efficiently, comprising the following steps: taking streptomyces roseosporus slant spore at normal temperature to prepare spore suspension by sterile water; inoculating 0.5ml of the spore suspension in a 250ml shake flask filled with 30ml of seed culture medium, and culturing for 48h in a shaker when the temperature is 28-32 DEG C and the revolution speed is 180-220 rpm; adding 1% of inoculum size in an automatic 7.5 LDE fermentation tank loaded with fermentation medium; adding one or combination of cofactor ferroheme or leucovorin or pyridoxal phosphate VB6 with the concentration of 0.5-30mg / L; and controlling the throughput to be 0.8-1.2v / v / m, the pH value to be 6.5-7.5 and fermenting for 90-144h at the temperature of 28-32 DEG C. By adopting the method in the invention to regulate biological enzyme activity to increase intracellular metabolism flux introduced in Daptomycin synthesis, the Daptomycin yield is improved; the method has simple operation and low cost; and in the streptomyces roseosporus fermented and cultured by the invention, the fermentation unit of the Daptomycin can be improved by 0.24-4.6 times compared with a contrast sample.