Transcription profiling by array of Bacillus cereus ATCC14579 and its isogenic SecDF deletion mutant
ABSTRACT: SecDF is a highly conserved accessory protein of the Sec-translocase located in the cytoplasmic membrane. The deletion mutant (delta Bc4405) of Bacillus cereus ATCC14579 shows multiple phenotypic changes, including aberrent cell division starting at transitionary phase. To understand the underlying processes genotypic profiling was carried out at 3h and 4h after inoculation. The morphology of the mutant seems to be more severe if glucose is added to the LB medium, thus all cultures contained 1% glucose.
The aim of this study was to explore the role of SecDF in protein secretion in Bacillus cereus ATCC 14579 by in-depth characterization of a markerless secDF knock out mutant. Deletion of secDF resulted in pleiotropic effects characterized by a moderately slower growth rate, aberrant cell morphology, enhanced susceptibility to xenobiotics, reduced virulence and motility. Most toxins, including food poisoning-associated enterotoxins Nhe, Hbl, and cytotoxin K, as well as phospholipase C were less a ...[more]
Project description:B. thuringiensis 407 nprA::lacZ strain was compared with an isogenic delta-nprR-nprX strain to explore the effects of nprR-nprX deletion. NprR is a transition state regulator which is activated towards the end of the exponential phase by a part of the signaling peptide NprX. We made direct comparisons of RNA from the two strains collected at T1 and T3, one and three hours after the transition to stationary phase, respectively. T1 was thought to be the early phase of NprR activation, while T3 was thought to be around the peak of NprR activation. All samples are biological replicates, and dye swap was performed between the different comparisons.
Project description:The transcriptional global profiles of the wild-type strain Bacillus thuringiensis 407 and a cdgF deletion mutant were compared after 1.5 hours of growth in an planktonic culture to analyze the effect of deletion of cdgF, which is involved in c-di-GMP signaling, on the global expression profile of B. thuringiensis 407
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Project description:Salmonella transcription profiles were obtained from samples flown on space shuttle mission STS-115, and compared to profiles from Salmonella grown under identical conditions on the ground. Keywords: stress response, transcriptional profile Triplicate experimental samples were hybridized to slides that contain three identical Salmonella ORF arrays. Each hybridization was performed with Cy3 labeled total RNA and Cy5 labeled gDNA as control.
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