A group from College of Life Sciences, Guizhou University, 550025 Guiyang, Guizhou, China has reported about relationship between peanut root exudates and changes in gene expression of the plant growth-promoting effects of burkholderia pyrrocinia strain P10.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10061817/
The peanut root exudates were mainly composed of organic acids and amino acids, but it also contained sugars, alcohols, fatty acids, sugar alcohols, sugar acids, and other components. The detected compounds included low-molecular-weight organic acids, such as malic acid, lactic acid, succinic acid, pyruvic acid, oxalic acid, and citric acid, which were present at relatively high concentrations. Various amino acids were also detected, including alanine, glycine, proline, valine, phenylalanine, isoleucine, tyrosine, methionine, threonine, glutamic acid, serine, lysine, asparagine, glutamine, and aspartic acid. Xylose, allose, lyxose, and ribose were the most prominent sugars in the peanut RE, which also contained fatty acids (e.g., palmitic acid, stearic acid, myristic acid, oleic acid, and palmitoleic acid), alcohols (e.g., 4-hydroxyphenylethanol, myo-inositol, and phytol), sugar alcohols (e.g., threitol, xylitol, sorbitol, and arabitol), sugar acids (e.g., galactonic acid, gluconic acid, and threonic acid), and some other components (e.g., indole-3-acetamide and urea).
And, the up-regulated genes of burkholderia pyrrocinia strain P10 tended to be associated with ATP binding cassette (ABC) transporters, steroid degradation, quorum sensing (QS), biosynthesis of siderophore group nonribosomal peptides, and galactose metabolism. More specifically, 47 genes with expression levels that were up-regulated by 1.01- to 5.83-times were associated with the transport of minerals and organic ions, oligosaccharides, monosaccharides, amino acids, peptides, iron-siderophores, and ATP binding cassette subfamily C (ABCC) subfamily members. In some cases, the transcription of an entire gene cluster was observed, including the ssuA-C-B genes responsible for alkanesulfonate transport, afuA-B-C genes (Fe3+ transport), proX-W-V genes (glycine betaine/proline transport), and araF-H-G genes (L-arabinose transport). Additionally, the expression of 19 genes involved in QS and four genes contributing to steroid degradation were up-regulated. The expression levels of three genes involved in the biosynthesis of siderophore group nonribosomal peptides and five genes related to galactose metabolism were also up-regulated. The expression of genes associated with strain P10 adhesion and biofilm formation were also up-regulated. In the pathways mediating the metabolism of glucose and mannose, amino sugars, and ribose, the expression of the mannose-1-phosphoguanyltransferase gene algA, which encodes the enzyme that converts mannose-1-phosphate to GDP-mannose, was up-regulated. The GDP-mannose is an important exopolysaccharide (EPS) constituent and the main component of biofilms.