Project description:Paenibacillus polymyxa is an agriculturally important plant growth promoting rhizobacterium (PGPR). Many Paenibacillus species are known to be engaged in complex bacteria-bacteria and bacteria-host interactions, which in other bacteria were shown to necessitate quorum sensing communication, but to date no quorum sensing systems have been described in Paenibacillus. Here we show that the type strain P. polymyxa ATCC 842 encodes at least 16 peptide-based communication systems. Each of these systems comprises a pro-peptide that is secreted to the growth medium and further processed to generate a mature short peptide. Each peptide has a cognate intracellular receptor of the RRNPP family, and we show that external addition of P. polymyxa communication peptides to the medium leads to reprogramming of the transcriptional response. We found that these quorum sensing systems are conserved across hundreds of species belonging to the Paenibacillaceae family, with some species encoding more than 25 different peptide-receptor pairs, representing a record number of quorum sensing systems encoded in a single genome.
Project description:Transcriptional profiling of the bacteria Paenibacillus vortex comparing control untreated cells with kanamycin treated cells after 18 hours of exposure. Goal was to determine the effect of the antibiotic kanamycin in concentration which affect the colony morphology on global bacteria gene expression. Two-condition experiment, control cells vs. kanamycin treated cells. Biological replicates: 2 control replicates, 2 treated replicates. Pooling of 5 technical replicates for each biological replicate.
Project description:Transcriptome profile was obtained from a set of human embryonic stem cell (hESCs) line (WA09: H9) with different passage numbers (P1: 40s, P2: 100s, P3: 200s, P4: 300s passage). Culture adaptation occurs in hESCs during repeated in vitro culture to acquire ‘survival advantage’ to be highly resistant to various stresses. In special, difference in gene expression profile of cell death or apoptotic gene signature was evident between P1/P2 and P3/P4 hESCs. Overall design: Microarray analysis of human embryonic stem cells (hESCs) with different passage numbers P1: H9 hESCs (40s passage), P2: H9 hESCs (100s passage), P3: H9 hESCs (200s passage), P4: H9 hESCs (300s passage)