RESUMEN
The study aimed to investigate whether rutin affects the quorum sensing (QS) of avian pathogenic Escherichia coli (APEC). In this study, APEC-O78 was selected as the test strain. We mainly examined the effects of rutin on the AI-2 secretion by bioluminescence assay, biofilm formation through a crystal violet staining method, and expression of virulence genes of APEC by qRT-PCR. We found that rutin can significantly interfering with QS through reducing the secretion of AI-2, inhibited the biofilm formation, and reduced the expression of virulence genes of APEC. Moreover, rutin markedly decreased adhesion and damage of APEC to chicken type II pneumocytes. These results suggested rutin reduces cell damage of APEC-infected chicken type II pneumocytes through interfering with QS via decreasing AI-2 production, biofilm formation, and the expression of virulence genes. This paper may provide a new evidence for colibacillosis prevention in chicken.
Asunto(s)
Biopelículas/efectos de los fármacos , Infecciones por Escherichia coli/veterinaria , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Percepción de Quorum/efectos de los fármacos , Rutina/antagonistas & inhibidores , Factores de Virulencia/genética , Adhesinas Bacterianas/efectos de los fármacos , Células Epiteliales Alveolares/microbiología , Animales , Biopelículas/crecimiento & desarrollo , Proteínas Portadoras/efectos de los fármacos , Proteínas Portadoras/genética , Supervivencia Celular/efectos de los fármacos , Pollos , Escherichia coli/crecimiento & desarrollo , Escherichia coli/patogenicidad , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/microbiología , Proteínas de Escherichia coli/efectos de los fármacos , Proteínas de Escherichia coli/genética , Regulación Bacteriana de la Expresión Génica/genética , L-Lactato Deshidrogenasa/análisis , Pruebas de Sensibilidad Microbiana , Enfermedades de las Aves de Corral/tratamiento farmacológico , Enfermedades de las Aves de Corral/microbiología , Rutina/química , Virulencia/efectos de los fármacos , Virulencia/genéticaRESUMEN
Verticillium wilt, caused by Verticillium dahliae Kleb., is a serious potato (Solanum tuberosum L.) disease worldwide, and biocontrol represents a promising eco-friendly strategy to reduce its impact. We used extracts from Canada milk vetch (CMV) and a set of four V. dahliae-antagonistic bacterial strains to coat potato seeds at planting and examined the degree of protection provided against V. dahliae as well as accumulation of soluble phenolics as markers for induced resistance. All tested treatments were effective in reducing disease severity, and CMV showed the highest level of protection. In this treatment, flavonol-glycoside rutin was a highly abundant compound induced in potato tissues, with levels two to three times higher than those detected in noninoculated controls and V. dahliae-inoculated plants. We investigated dose-dependent effects of rutin on V. dahliae growth and sporulation in vitro and in planta. The effect of rutin on mycelial growth was inconsistent between disk assay and amended medium experiments. On the other hand, significant reduction of V. dahliae sporulation in vitro was consistently observed starting at 300 and 100 µM for isolates Vd-9 and Vd-21, respectively. We successfully detected 2-protocatechuoylphloroglucinolcarboxylic acid (2-PCPGCA) using ultra-performance liquid chromatography tandem mass spectrometry, indicating that V. dahliae dioxygenally oxidizes quercetin. Quercetin, as an aglycone, is freed from the sugar moiety by glucosidases and rhamnosidases produced by the fungus and is a substrate for quercetinases. The occurrence of quercetinases in V. dahliae provides a background to formulate a hypothesis about how by-product 2-PCPGCA may be interfering with potato defenses.