ABSTRACT
The impact of 1-(4-amino-2-hydroxyphenyl)ethanone (AHPE) from the metabolites of endophytic fungus Phomopsis liquidambari on quorum sensing (QS) of Agrobacterium tumefaciens was evaluated for the first time in this study. Exposure to AHPE at concentrations ranging from 12.5 to 50 µg/mL, the ß-galactosidase activity, acyl-homoserine lactone level, swimming motility, chemotaxis, and flagella formation were significantly inhibited. qRT-PCR quantification combined with the docking analysis demonstrated that AHPE affected the QS system of A. tumefaciens by repressing the transcriptional levels of traI and traR rather than signal mimicry. 1H NMR-based metabolic analysis indicated that the metabolism of A. tumefaciens was notably disturbed with AHPE treatment. AHPE treatment also resulted in the enhanced oxidative stress in A. tumefaciens. The enhanced oxidative stress lead to the disorder of energy supply, protein synthesis, and nucleotide metabolism, and ultimately attenuated the pathogenicity of A. tumefaciens. Our study indicated that AHPE can serve as a potential pesticide to defend against A. tumefaciens.
ABSTRACT
An organocatalytic chemo- and regioselective C6-functionalization of 2,3-disubstituted indoles has been established via a reaction with ortho-hydroxybenzyl alcohols, which afforded biologically important diarylindol-6-ylmethanes in overall high yields (up to 99% yield). This protocol not only provides an efficient method for constructing biologically important diarylindol-6-ylmethane frameworks in an atom economical fashion, but also serves as a good example for the direct catalytic C6-functionalization of indoles, which have been rarely investigated. More importantly, the preliminary biological evaluation revealed that this new class of diarylindol-6-ylmethanes exhibited strong cytotoxicity to HeLa cell lines.
