The purpose of this study was to investigate the regulatory effects of biofilm associated non-coding small RNA(sRNA)00085 on the survival and environmental fitness of Listeria monocytogenes.Homologous recombination technology was used to construct a deletion mutant strain(△sRNA 00085)and a complementary strain(C △sRNA 00085)of the sRNA00085 target gene.The differences in biological characteristics were compared among the standard strain,△sRNA 00085,and C△sRNA 00085.The deletion of sRNA00085 led to a significant decrease in biofilm formation capacity and sensitivity to several antibiotics,including penicillin,piperacillin,doxycycline,tetracycline,vancomycin,and cotrimoxazole.However,only the minimum inhibitory concentration(MIC)of tetracycline exhibited a significant decrease in △sRNA00085.Meanwhile,the decreased biofilm formation and antibiotic resistance of the sRNA00085 mutant were restored in the C△sRNA00085 strain.Furthermore,we investigated the transcription levels of tetracycline resistance-related genes in L.monocytogenes.Down-regu-lated transcription of the tetS gene but no significant difference in transcription of the tetA gene were observed in △sRNA 00085 compared with the standard strain and C△sRNA00085.Moreover,the elimination of sRNA00085 did not affect bacterial growth ability or sensitivity to disinfectants.These findings highlight that sRNA00085 plays an important role in the environ-mental adaptability of L.monocytogenes by affecting bacterial biofilm formation and resistance.
关键词
单核细胞增生李斯特菌/非编码小RNA/生物被膜/耐药性/环境适应性
Key words
Listeria monocytogenes/non-coding small RNA/biofilm/resistance/environmental fitness