原儿茶醛对阪崎克罗诺肠杆菌毒力因子的抑制作用

Inhibition of Protocatechuic Aldehyde on Virulence Factors of Cronobacter sakazakii

探究植物源活性物质原儿茶醛对阪崎克罗诺肠杆菌泳动运动能力、生物被膜形成能力、黏附和侵入Caco-2细胞能力及9种与菌体相关毒力基因转录的影响。结果表明,原儿茶醛对6株阪崎克罗诺肠杆菌实验菌株的最小抑菌质量浓度(minimal inhibitory concentrations,MIC)和最小杀菌质量浓度均为2 mg/mL,对阪崎肠杆菌ATCC29544亚抑制浓度分别为1/200、1/100 MIC和1/50 MIC。亚抑制浓度的原儿茶醛能够抑制阪崎克罗诺肠杆菌在琼脂软平板中泳动运动能力;减弱菌体在12℃和25℃下不同时间段(24、48、72 h)生物被膜的形成能力;降低细菌黏附及侵入Caco-2细胞能力;下调9种与菌体相关毒力基因的转录量。研究结果表明原儿茶醛能够抑制阪崎克罗诺肠杆菌多种毒力因子,其有潜力作为抗生素补充剂或抗毒性物质预防及控制阪崎克罗诺肠杆菌引起的相关感染。

The aim of this study was to evaluate the inhibitory effect of protocatechuic aldehyde(PA),a plant-derived compound,on the swimming motility,bio film formation,adhesion and invasion to Caco-2 cells of Cronobacter sakazakii and to determine its effect on the transcription of nine virulence genes in C.sakazakii.The results indicated that the minimal inhibitory concentrations(MICs)and minimal bactericidal concentrations(MBCs)of PA against six C.sakazakii strains were 2 mg/mL,and the sub-inhibitory concentrations against C.sakazakii ATCC29544 were 1/200,1/100 and 1/50 MIC.PA at SICs inhibited the swimming motility on soft agar plates and biofilm formation of ATCC29544.PA substantially reduced its adhesion and invasion to Caco-2 cells,and repressed the expression of nine virulence genes in this strain.These findings suggest that PA can inhibit the virulence factors of C.sakazakii,and it has the potential to be developed as an alternative or supplemental agent to prevent and control infections caused by C.sakazakii.