Oak Bark (Quercus sp. cortex) Protects Plants Through the Inhibition of Quorum Sensing Mediated Virulence of Pectobacterium carotovorum

Abstract

Bacterial intercellular communication mediated by small diffusible molecules, known as quorum sensing (QS), is a common mechanism for regulating bacterial colonisation strategies and survival. Influence on QS by plant-derived molecules is proposed as a strategy for combating phytopathogens by modulating their virulence. This work builds upon other studies that have revealed plant-derived QS inhibitors extracted from oak bark (Quercus sp.). It was found that co-incubation of Pectobacterium carotovorum VKM-B-1247 with oak bark extract (OBE) reduced the production of acyl-HSL. This was accompanied by a dose-dependent decrease in the bacterial cellulolytic and protease activity. The effect of OBE treatment at the transcriptomic level is the suppression of the main QS-related genes expR / expI. Potato tubers pre-treated with OBE showed resistance to a manifestation of soft-rot symptoms. Analysis of the component composition of the OBE identified several biologically active molecules, such as n-hexadecanoic acid, 2,6-di-tert-butyl-4-methylphenol, butylated hydroxytoluene (BHT), gamma-sitosterol, lupeol, and others. Molecular docking of the binding energy of the identified molecules with homology models of LuxR-LuxI type proteins showed high potential binding of a few plant-derived molecules to these proteins.

A new species of Ranunculus (Ranunculaceae) from Western Pamir-Alay, Uzbekistan

“…The populations were detected again in 2019 while working on the Flora of Uzbekistan Project ( Sennikov et al 2016 ). It should be noted that the flora of the Western Pamir-Alay is characterised by a high taxonomic diversity ( Kamelin 1973 ; Vasilchenko and Vasileva 1985 ; Tojibaev et al 2016 ; Makhmudjanov et al 2019 ; Yusupov et al 2020 ).…”