Project description:One of the most distinct features of Pseudoalteromonas sp. SCSIO 11900 is its ability to form a very robust pellicle than most Pseudoalteromonas strains. Thus we want to identify the genes essential for the pellicle formation of SCSIO 11900. We compared transcriptom profiles of planktonic cells, initial pellicle and mature pellicle of coral Pseudoalteromonas sp. SCSIO 11900 and revealed that some unique genes from horizontal gene transfer is involved in the pellicle formation of SCSIO 11900.
Project description:We compared genetic profiles of planktonic stage to biofilm stage of deep sea bacterium Pseudoalteromonas sp. SM9913 and revealed genetic features during switch from planktonic to pellicle stage in Pseudoalteromonas sp. SM9913.
Project description:We compared genetic profiles of planktonic stage to biofilm stage of deep sea bacterium Pseudoalteromonas sp. SM9913 and revealed genetic features during switch from planktonic to pellicle stage in Pseudoalteromonas sp. SM9913. mRNA profiles of Pseudoalteromonas sp. SM9913 planktonic cells, initial pellicle cells and mature pellicle cells were generated by Illumina Hiseq2000.
Project description:Transcriptomic sequencing was performed to obtain the key functional genes involved in the adaptation of oxidative stress induced by hydrogen peroxide (H2O2) in the Arctic bacterium Pseudoalteromonas sp. A2. Exposure to 1 mmol/L H2O2 resulted in large alterations of the transcriptome profile, including significant upregulation of 109 genes and significant downregulation of 174 genes. Functional classification of differentially expressed genes revealed that most of genes affiliated with biological adhesion, negative regulation of biological process, enzyme regulator activity, protein binding transcription factor activity and structural molecular activity were upregulated, and most of genes affiliated with multicellular organismal process and extracellular region were downregulated. It was notably that fifteen genes affiliated with flagella and four genes affiliated with heat shock proteins were significantly upregulated. Meanwhile, nine genes affiliated with cytochrome and cytochrome oxidase, and five genes affiliated with TonB-dependent receptor, were significantly downregulated. However, eighteen genes with antioxidant activity categorized by GO analysis showed differential expressions. This overall survey of transcriptome and oxidative stress-relevant genes can contribute to understand the adaptive mechanism of Arctic bacteria. five significant upregulated genes and five significant downregulated genes were selected using qRT-PCR to cinduct the oxidative stress. overall survey of transcriptomic sequencing by RNA-Seq of the Pseudoalteromonas sp. A2, an isolate from seawater with high activity against H2O2
Project description:Genome mining of pigmented Pseudoalteromonas has revealed a large potential for production of bioactive compounds, both hydrolytic enzymes and secondary metabolites and the purpose of the present study was to explore this bioactivity potential in a potent antibiotic and enzyme producer, Pseudoalteromonas rubra strain S4059. Proteomic analyses indicated that a highly efficient chitin degradation machinery was present in the red-pigmented P. rubra S4059 when grown on chitin. Four GH18 chitinases and two GH20 hexosaminidases were significantly upregulated by chitin. GH19 chitinase which is not common in bacteria is consistently found in pigmented Pseudoalteromonas and in S4059 it was only detected when the bacterium was grown on chitin. To explore the possible role of GH19 in pigmented Pseudoalteromonas, we deleted the GH19 chitinase and compared a range of phenotypes in the mutant and wild type. Neither, the chitin degrading ability or the biofilm forming capacity was affected by GH19 deletion. In some Vibrionaceae, the secondary metabolome is significantly affected by growth on chitin as compared to simpler carbon sources. The secondary metabolites produced by S4059 and the GH19 mutant were xxx start by chitin/mannose – then the mutant. not altered by the absence of the gene, indicating that chitin utilization may not directly influence the production of secondary metabolites as has been observed in some Vibrionaceae. Metabolome analysis reveal that growth on chitin XX. In summary,
