Pichia pastoris strain capable of utilizing non methyl alcohol carbon source induced AOX1 promoter to express outside source protein

Abstract

The invention provides a plurality of Pichia pastoris strains capable of utilizing non methyl alcohol carbon source induced AOX1 promoter to express outside source protein. PpHXT1 gene in the Pichia pastoris strain mutates, thus protein can not be coded or the coded protein has no activity, and autophagy gene PpATG30 gene also mutates, thus protein can not be coded or the coded protein has no activity; or PpMIG1 gene in the Pichia pastoris strain mutates, thus protein can not be coded or the coded protein has no activity, and PpMIG2 gene in the Pichia pastoris strain mutates, thus protein can not be coded or the coded protein has no activity. The Pichia pastoris strain of the invention not only has the advantages of the existing Pichia pastoris strain but also can utilize non methyl alcohol carbon source induced AOX1 promoter to express outside source protein, is safe and environmentally friendly, has simple operation and lower cost, also can be applied to production of food or additive and is applicable to large-scale popularization and application.

Description

technical field [0001] The present invention relates to the technical field of bioengineering and biopharmaceuticals, more specifically, to the technical field of expression strains, in particular to a Pichia yeast strain that can use non-methanol carbon sources to induce the expression of foreign proteins from the AOX1 promoter. Background technique [0002] As of 2006, more than 500 foreign proteins have been expressed in Pichia pastoris, and these proteins are derived from the entire biological kingdom, including viruses, bacteria, fungi, plants, insects and vertebrates. The promoter used by Pichia pastoris to express foreign protein is the promoter of AOX1 (Alcohol oxidase 1, alcohol oxidase gene). Fructose, glycerol, etc.) inhibit the expression of AOX1 promoter. [0003] The reason why so many exogenous proteins are expressed using the Pichia pastoris expression system is that it has incomparable advantages over other expression systems, such as the simple operation o...

AI Technical Summary

Problems solved by technology

[0005] 1. When inducing the expression of exogenous recombinant proteins, methanol must be used as a carbon source. Methanol is toxic and flammable. In industrial production, the workshop needs to be designed for riot prevention, resulting in increased costs;

[0006] 2. Methanol fermentation consumes a lot of oxygen. Generally, it is difficult to meet the demand for oxygen by increasing the ventilation volume and speed of the air, and pure oxygen is needed. The more methanol consumed, the more pure oxygen is needed, which brings great harm to the actual industrial production. In addition, the more methanol consumed, the greater the heat produced, and the higher the cooling capacity requirements of the required equipment;

[0007] 3. As a petrochemical product, methanol is not suitable for the production of food or additives;

[0008] 4. Methanol metabolism produces H 2 o 2 , leading to hydrolysis of the expressed protein;

[0009] 5. The high-efficiency transcription of AOX1 is inseparable from methanol, and suffers from carbon source repression in other carbon sources

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