InduciblespyTranscription Acts as a Sensor for Envelope Stress ofSalmonella typhimurium.
Salmonella entericainfects a broad range of host animals, and zoonostic infection threatens both public health and the livestock and meat processing industries. Many antimicrobials have been developed to targetSalmonellaenvelope that performs essential bacterial functions; however, there are very few analytical methods that can be used to validate the efficacy of these antimicrobials. In this study, to develop a potential biosensor forSalmonellaenvelope stress, we examined the transcription of theS. entericaserovartyphimurium spygene, the ortholog of which inEscherichia coliencodes Spy (spheroplast protein y). Spy is a chaperone protein expressed and localized in the periplasm ofE. coliduring spheroplast formation, or by exposure to protein denaturing conditions.spyexpression inS. typhimuriumwas examined by constructing aspy-gfptranscriptional fusion.S. typhimurium spytranscription was strongly induced during spheroplast formation, and also when exposed to membrane-disrupting agents, including ethanol and the antimicrobial peptide polymyxin B. Moreover,spyinduction required the activity of regulator proteins BaeR and CpxR, which are part of the major envelope stress response systems BaeS/BaeR and CpxA/CpxR, respectively. Results suggest that monitoringspytranscription may be useful to determine whether a molecule particularly cause envelope stress inSalmonella.
Department of Microbiology and Immunology, Chosun University School of Dentistry, Gwangju 61452, Korea.
Seon Mi
SM
Jeong
Department of Microbiology and Immunology, Chosun University School of Dentistry, Gwangju 61452, Korea.
Hwa Jeong
HJ
Lee
Department of Microbiology and Immunology, Chosun University School of Dentistry, Gwangju 61452, Korea.
Yoon Mee
YM
Park
Division of Life Science, College of Life Sciences and Biotechnology, Korea University, Seoul 02841, Korea.
Jin Seok
JS
Kim
Department of Biological Sciences, Seonam University, Namwon 55724, Korea.
Sang Dae
SD
Lee
Department of Microbiology and Immunology, Chosun University School of Dentistry, Gwangju 61452, Korea.
Iel Soo
IS
Bang
Salmonella; Spy; envelope stress; extracytoplasmic chaperone