Analysis of TNT (2,4,6-Trinitrotoluene)-Inducible Cellular Responses and Stress Shock Proteome in Stenotrophomonas sp. OK-5

Abstract

In this study, the cellular responses of Stenotrophomonas sp. OK-5 to explosive 2,4,6-trinitrotoluene (TNT) have been extensively analyzed. The stress shock proteins, which might contribute to enhancing cellular resistance to TNT-mediated toxicity, were induced at different concentrations of TNT used as a substrate for cell culture of Stenotrophomonas sp. OK-5 capable of utilizing TNT. Proteomic analysis for 2-DE of soluble protein fractions from the culture of OK-5 exposed to TNT demonstrated approximately 300 spots on the silver-stained gel ranging from pH 3 to pH 10. Among them, 10 spots significantly induced and expressed in response to TNT were selected and analyzed. As the result of internal amino acid sequencing with ESI-Q TOF mass spectrometry, TNT-mediated stress shock proteins such as DnaK, OmpW, and OsmC were identified and characterized. Survival of strain OK-5 was periodically monitored in the presence of different concentrations of TNT along with the production of the stress shock proteins. Cells of strain OK-5 pre-exposed to TNT had in improved survival tolerance. Analysis of total cellular fatty acids in strain OK-5 suggested that several saturated or unsaturated fatty acids might increase or decrease under TNT-mediated stress condition. Scanning electron microscopy of cells treated with 0.8 mM TNT for 12 h revealed irregular rod shapes with wrinkled surfaces.

Antibacterial Effects of Green Tea Polyphenols on Clinical Isolates of Methicillin-Resistant Staphylococcus aureus

“…After overnight incubation at 4°C, the precipitate was centrifuged at 10,000 g for 30 min at 4°C and washed with ice-cold 100% acetone [1,2]. 2-DE was performed according to previously described methods [9]. Isoelectric focusing (IEF) was performed with the Ettan IPG phor System (Amersham Biosciences, Uppsala, Sweden) according to the manufacturer's guidelines.…”

“…In-Gel Digestion and MALDI-TOF/MS Protein spots were excised from silver-stained 2-DE gels, and peptides digested with trypsin according to previously described methods [9,14]. Digested peptides were redissolved using 0.1% trifluoroacetic acid (TFA).…”

Cellular Responses of Salmonella typhimurium Exposed to Green Tea Polyphenols

“…S. typhimurium 세포 를 포함하는 한천블록은 그 후 phosphate buffer에서 37℃, 12시 간 동안 3,000 µg/ml TPP에 노출시켰다. 그후 TPP로 처리된 집 락들은 고정, 탈수, 금으로 코팅 등의 이전에 기술된 방법에 따 라, Hitachi S-2500C 주사전자현미경(Hitachi, Japan)으로 조사 하였다 (Ho et al, 2004). …”

“…2-DE는 이전에 기술된 방법에 따라 실시되었다 (Ho et al, 2004). 염색된 protein spot은 젤에서 잘라내어, 30 mM potassium ferricyanide와 100 mM sodium thiosulfate를 사용하여 탈염색 하고, 증류수로 세척하였다.…”

Insights into the Extracytoplasmic Stress Response of Xanthomonas campestris pv. campestris : Role and Regulation of σ E -Dependent Activity

“…In addition, three genes encode cell envelope proteins. Among them, XCC0539 encodes a pre-dicted member of the OmpW/AlkL family that is found in all Gram-negative bacteria and is involved in the protection of bacteria against various forms of environmental stress (36). pglA encodes a predicted polygalacturonase (PG) to selectively degrade the pectic polymers of the plant cell walls, and PGs are virulence factors in closely related bacterial species (73).…”