Method of degrading lignin of plants with engineering bacteria of saccharomyces cerevisiae

Abstract

The invention discloses a method of degrading lignin of plants with engineering bacteria of brewing yeast and belongs to the biotechnology field. The method includes following steps: (I) cloning lignin peroxidase gene, manganese peroxidase gene and laccase gene from the microorganisms; (II) constructing a brewing yeast expression carrier containing the three gene expression frames; (III) converting the brewing yeast expression carrier into brewing yeast; and (IV) performing G418 resistance screening to obtain the engineering bacteria of brewing yeast containing the gene expression frames of the lignin peroxidase gene, the manganese peroxidase gene and the laccase gene; and (V) degrading the lignin of plants by means of reaction between the three engineering bacteria of brewing yeast and plant raw materials. The degradation effect of the engineering bacteria of brewing yeast on the lignin is stronger than that of a natural microorganism which naturally expresses and secretes manganese peroxidase, lignin peroxidase and laccase and is used for degrading the lignin of the plants.

Description

technical field [0001] The invention belongs to the field of biotechnology and relates to a method for constructing and applying microbial engineering bacteria. Specifically, it is a method for degrading lignin of plant raw materials by using microbial engineering bacteria. Background technique [0002] Manganese Peroxidase (MnP), Lignin Peroxidase (LiP) and Laccase have the function of degrading lignin together. [0003] Plant resources are constantly regenerated and are very rich. The basic components of plants are cellulose, hemicellulose and lignin. Among them, the most useful component in the manufacture of biogas and ethanol industry is cellulose, followed by hemicellulose. The former is composed of glucose while the latter is composed of pentose sugars. These sugars are converted into ethanol and biogas. However, the cellulose molecules are inlaid with lignin, and the inlaid cellulose cannot be hydrolyzed. Lignin is an amorphous, aromatic polymer containing oxyp...

AI Technical Summary

Problems solved by technology

The advantage of using white rot fungi to degrade plant lignin is that white rot fungi have a complete enzyme system for degrading lignin (manganese peroxidase, lignin peroxidase and laccase). The manganese peroxidase gene, lignin peroxidase gene and laccase gene contained in the fungus are only a single copy, and the yield of the expressed enzyme is small, and the growth of white rot fungi is slow, and the cycle of degrading lignin is long

Images