Study On The Function Of Gene YogA In Paenibacillus Polymyxa SC2

Paenibacillus polymyxa SC2 is a plant-growth-promoting rhizobacteria from pepper rhizosphere soil in the laboratory.The SC2 have various physiological characteristics,and it can produce kinds of stimulating metabolites such as cytokines and cytokinins,and also can secrete many higher value antibiotics such as fusaricidins and polymyxin.So the SC2 have broad antibacterial spectrum,obvious growth promotion effect and good disease resistance of crops.However,the P.polymyxa SC2 strain was unstable under laboratory conditions and easily mutated.In this study,the mutant strain P.polymyxa SC2-M1 with stable traits was used as the experimental strain.Through preliminary analysis of P.polymyxa SC2 whole genome and proteomics predicted the interaction between YogA(alcohol dehydrogenase)and FusE(aldehyde dehydrogenase).It is predicted that YogA may participate in related metabolic pathways together with FusE.To further clarify YogA functions,this study performed a comparative analysis of the yogA gene,and was constructed a yogA gene knockout strain that combined with omics data to analyze the function of yogA gene.In the experiment,the homologous recombination method was used to knock out the yogA gene in P.polymyxa SC2-M1,and to overexpress the yogA gene with a strong promoter plasmid.The growth ability of knockout and over-expressing strains showed that the yogA gene regulated bacterial growth and metabolism,and the growth rate was significantly improved after knock-out and became slower after over-expression.The bacteriostatic experiment of the knockout strain showed that the ability of antagonize the fungus was almost unchanged after the knockout of the yogA gene,but the ability of antagonize the bacteria became weak.The verification of the interaction between YogA protein and FusE protein by yeast two-hybrid technology showed that there was a protein interaction relationship,but the interaction ability was weak.The yogA gene knockout strain was subjected to transcriptome sequencing analysis.A total of 1096 genes were upregulated and 671 genes were downregulated.By analyzing the metabolic pathways involved in differential genes,it was found that they(as a catalytically active enzyme,transporter,binding molecule,transcription regulator,cell component,etc.)were mainly involved in the metabolism of different pathways,mainly included glycolysis,gluconeogenesis,anabolic metabolism of amino acids,starch and sugar metabolism,chemotaxis of bacteria,biosynthesis of antibiotics,microbial metabolism in different environments,fatty acid synthesis degradation,carbon metabolism,etc.Compared with the starting strain,the metabolome analysis results of the yogA gene knockout strain showed that enrich the metabolic pathways identified by the metabolites,which were mainly involved in various metabolic pathways such as metabolism,amino acid synthesis and metabolism,bacterial chemotaxis,biosynthesis of secondary metabolites,antibiotic biosynthesis,and transmembrane transport.It was more consistent with transcriptional differential genes involved in metabolic pathways.Then,through transcription and metabolomics,it was proved that the yogA gene and the expression product YogA were involved in the predicted metabolism and perform similar functions as AdhA.In the end,both could be identified as isozymes.In this study,the functions of the yogA gene in P.polymyxa SC2-M1 were analyzed.It was beneficial to the improvement of the functions and types of ADH in P.polymyxa SC2-M1.Therefore,it laid the foundation for the basic metabolism and application of the strain.