Cupriavidus sp. HN-2, a Novel Quorum Quenching Bacterial Isolate, is a Potent Biocontrol Agent Against Xanthomonas campestris pv. campestris

Abstract

Diffusible signal factor (DSF) represents a family of widely conserved quorum sensing (QS) signals involved in the regulation of virulence factor production in many Gram-negative bacterial pathogens. Quorum quenching, which disrupts QS either by degradation of QS signals or interference of signal generation or perception, is a promising strategy for prevention and control of QS-mediated bacterial infections. In this study, a novel DSF-degrading strain, HN-2, was isolated from contaminated soil and identified as Cupriavidus sp. The isolate exhibited superior DSF degradation activity and completely degraded 2 mmol·L–1 of DSF within 24 h. Analysis of the degradation products of DSF by gas chromatography–mass spectrometry led to the identification of trans-2-decenoic acid methyl ester as the main intermediate product, suggesting that DSF could be degraded by oxidation and hydroxylation. Moreover, this study presents for the first time, evidence that Cupriavidus sp. can reduce the black rot disease caused by Xanthomonas campestris pv. campestris (Xcc). Application of the HN-2 strain as a biocontrol agent could substantially reduce the disease severity. These findings reveal the biochemical basis of a highly efficient DSF-degrading bacterial isolate and present a useful agent for controlling infectious diseases caused by DSF-dependent bacterial pathogens.

Enhanced Cypermethrin Degradation Kinetics and Metabolic Pathway in Bacillus thuringiensis Strain SG4

“…The first-order kinetic equation was followed to fit experimental data of cypermethrin degradation kinetics as follows [40]:…”

Insights Into the Biodegradation of Lindane (γ-Hexachlorocyclohexane) Using a Microbial System

“…Microbial consortiums communicated with each other via the mechanism known as quorum sensing (Ye et al, 2019(Ye et al, , 2020. Due to this communication in the lindane-contaminated sites, the metabolic burden is divided into various members and the consortium perform complex functions.…”

Characterization of a Novel Quorum-Quenching Bacterial Strain, Burkholderia anthina HN-8, and Its Biocontrol Potential against Black Rot Disease Caused by Xanthomonas campestris pv. campestris

“…The prevention and control of black rot disease have become important concerns, due to the hugely destructive impacts of block rot disease on the productivity and quality of cruciferous plants [ 11 ]. In recent years, QQ has been increasingly interested in the development of a biocontrol method based on QS of microorganisms as an alternative and effective way to control plant diseases [ 16 , 17 , 47 , 48 ]. Among all of the methods of QQ, biocontrol bacteria with degrading signal molecule activity have appeared as efficient tools in plant disease management [ 49 ].…”

“…The cultures were incubated at 30 °C and 200 rpm, and the same volume of cultures was taken out and centrifuged to obtain the supernatant, where the residual DSF was extracted from different intervals [ 46 ]. HPLC was performed to determine the amount of residual DSF under the following conditions: C 18 reverse chromatographic column, flow rate of 1 mL·min −1 , column temperature of 35 °C, mobile phase of methanol/water = 80:20 ( ν : ν ), detection wavelength of 210 nm, and injection quantity of 20 μL [ 47 ]. Each treatment was replicated three times.…”

“…The analytical conditions for GC–MS were as follows: injection amount, 1.0 μL; injection mode into the gas chromatograph, split with a 10:1 ratio; capillary column, HP-5 MS Ultra Inert column (30 m\0.25 μm\0.25 μm); column oven temperature, 60 °C for 5 min, then an increase of 10 °C/min, followed by 300 °C for 29 min; injection port temperature, 280 °C; carrier gas, helium; analytical mode, scan mode. Mass spectra were recorded in the m / z range of 40–430 [ 47 , 48 ].…”