Functional mechanism of plant growth retardation by Bacillus subtilis IJ-31 and its allelochemicals.
We previously isolated a rhizobacterium (Bacillus subtilis IJ-31) and demonstrated that its associated allelochemicals could indicate plant growth retardation. However, little is known about how the growth of plants is regulated by B. subtilis IJ-31 and its allelochemicals. In this study, we investigated whether plant growth retardation in this relationship occurred through the inhibition of gibberellin (GA) biosynthesis. GA 3beta-hydroxylase activity was found to be inhibited by B. subtilis IJ-31 and hydrocinnamic acid (HCA), which is one of the allelochemicals produced by B. subtilis IJ-31. Additionally, thin layer chromatography (TLC) demonstrated that B. subtilis IJ-31 culture broth and HCA both inhibit GA 3beta-hydroxylase (MBP-GA4) activity. The retardation of plants by HCA was then confirmed in vivo and in vitro using a Ryegrass and Arabidopsis growth retardation assay. Furthermore, treatment with either B. subtilis IJ-31 culture extract or its allelochemicals resulted in significant down-regulation of XTR9 gene expression in Arabidopsis. Overall, we identified the functional mechanism of plant growth retardation by B. subtilis IJ-31 and its allelochemicals.
Department of Agricultural Chemistry, College of Agriculture and Life Sciences, Kyungpook National University, Daegu 702-701, Korea.
Won-Chan
WC
Kim
In-Koo
IK
Rhee
D017360:Arabidopsis / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000254:growth & development*; D001412:Bacillus subtilis / Q000737:chemistry*; D002212:Capsicum / Q000187:drug effects / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D002855:Chromatography, Thin Layer; D015536:Down-Regulation; D004789:Enzyme Activation; D057075:Enzyme Assays; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D005875:Gibberellins / Q000096:biosynthesis; D016695:Glycosyltransferases / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000235:genetics; D008129:Lolium / Q000187:drug effects / Q000201:enzymology / Q000235:genetics / Q000254:growth & development*; D006899:Mixed Function Oxygenases / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000235:genetics; D010666:Phenylpropionates / Q000737:chemistry / Q000494:pharmacology; D010675:Pheromones / Q000737:chemistry / Q000494:pharmacology*; D010940:Plant Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000235:genetics
D004791:Enzyme Inhibitors; D005875:Gibberellins; D010666:Phenylpropionates; D010675:Pheromones; D010940:Plant Proteins; C035253:3-phenylpropionic acid; D006899:Mixed Function Oxygenases; C108186:gibberellin 3beta-hydroxylase; D016695:Glycosyltransferases; C073693:xyloglucan endotransglycosylase