Construction of SHP-GLOX Straw Lignin Degulation System and Its Application Effect in Rice

Backgroud: Rice straw is the crucial biomass for raw materials in China. Rice straw usage is limited due to its high lignin content, and the reduction of its lignin content could have economic and environmental benefits. Soybean hull peroxidase (SHP), a class III plant peroxidase, is derived from multiple sources. It has several advantages, such as high resistance to heat, high stability under acidic and alkaline conditions, and broad substrates range. SHP is speculated to be useful for lignin degradation. Glyoxal oxidase (GLOX) is an extracellular oxidase that can oxidize glyoxal and methylglyoxal in the extracellular medium to generate H 2 O 2 . Results In the present study, the SHP gene and the GLOX gene in the pCAMBIA3301-glycine-rich protein (GRP)-SHP-GLOX, designated as the K167 vector, was optimized and introduced into rice embryos using Agrobacterium -mediated transformation. Positive transgenic rice embryos were examined using molecular, physiological, biochemical tests and fermentation tests. The outcomes suggested that SHP degraded lignin effectively. Conclusions This research has created a breeding material that does not basically affect the normal growth and yield of rice, but the rice stalks are more likely to be degraded in the later stage, and used to breed rice varieties whose stalks are easy to use for energy. Our results will improve the industrial and commercial applications of rice straw.