Method for recombining Saccharopolyspora erythraea strain containing exogenetic vitreoscilla hemoglobin gene (vgb)

Abstract

The invention belongs to the technical field of gene engineering, and provides a method for recombining a Saccharopolyspora erythraea strain containing exogenetic vitreoscilla hemoglobin gene (vgb). In the method, vitreoscilla hemoglobin (VHb) expressed by the vitreoscilla hemoglobin gene (vgb) can be combined with oxygen to form an oxygen-binding state, and intervenes several key steps or branch pints in cell metabolic paths related with oxygen in the mode, so that the cell growth speed is improved, the cell respiration intensity is improved and the critical oxygen concentration of cells is reduced. In large dissolved oxygen change, a constant respiratory rate is kept, and the cell culture density and exogenetic gene expression are improved under low oxygen condition. The method solves the problem that in a large-scale bioreactor, because thalli are positioned in a viscous, enclosed and complicated environment with rich nutrients, oxygen required by massive mycelia in an exponential phase is limited, and the yield of erythrocin is reduced. The method has important application value for the antibiotic fermentation industry and high density cell culture, which have high oxygen consumption and take dissolved oxygen as a limiting factor.

Description

Technical field: [0001] The invention belongs to the technical field of genetic engineering and relates to a method for recombining a Saccharopolyspora erythromyces strain containing exogenous VGB. Background technique: [0002] The invention comes from the Liaoning Provincial Department of Education Youth Talent Fund Project "Research No.05L433 on Transforming Saccharopolyspora Erythromycetes to Increase Erythromycin Production and Reduce Costs". Saccharopolyspora erythromycetes is an engineered strain that produces macrolide antibiotic erythromycin. The industrial production of erythromycin belongs to aerobic fermentation. Due to the viscous, nutrient-rich, and airtight complex environment during the culture of the bacteria, the oxygen required by the massive mycelium in the logarithmic growth phase is limited, thereby Reduce the production of erythromycin. Improving the utilization rate of oxygen in large-scale bioreactors is an effective way to solve this problem. Howe...

AI Technical Summary

Problems solved by technology

The industrial production of erythromycin belongs to aerobic fermentation. Due to the viscous, nutrient-rich, and airtight complex environment during the culture of the bacteria, the oxygen required by the massive mycelium in the logarithmic growth phase is limited, thereby reduce the production of erythromycin

Improving the utilization of oxygen in large-scale bioreactors is an effective way to solve this problem. However, the problem of oxygen limitation in the formation of massive mycelium cannot be improved by improving the gas-liquid transfer rate.

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