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: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. mRNA profiles of Pseudoalteromonas sp. SM9913 planktonic cells, initial pellicle cells and mature pellicle cells were generated by Illumina Hiseq2000.
Project description:MS/MS data obtained from crude extracts from Pseudoalteromonas sp. This data is not publisher yet, so, contact Mr. Christian Martin before use it.
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:Investigation of whole genome gene expression level in motile strain of Sphingomonas. sp A1 All flagellar genes in motile strain of Sphingomonas. sp A1 are highly transcribed.
Project description:Prodiginines are a family of red-pigmented secondary metabolites with multiple biological activities. The biosynthesis of prodiginines is affected by various physiological and environmental factors. Thus, prodiginine biosynthesis regulation is highly complex and multifaceted. Although the regulatory mechanism for prodiginine biosynthesis has been extensively studied in Serratia and Streptomyces species, little is known about that in the marine betaproteobacterium Pseudoalteromonas In this study, we report that stringent starvation protein A (SspA), an RNA polymerase-associated regulatory protein, is required for the biosynthesis of prodiginine in Pseudoalteromonas sp. strain R3. The strain lacking sspA (ΔsspA) fails to produce prodiginine, which resulted from the downregulation of the prodiginine biosynthetic gene (pig) cluster. The effect of SspA on prodiginine biosynthesis is independent of histone-like nucleoid structuring protein (H-NS) and RpoS (σS). Further analysis demonstrates that the ΔsspA strain has a significant decrease in the transcription of the siderophore biosynthesis gene (pvd) cluster, leading to the inhibition of siderophore production and iron uptake. The ΔsspA strain regains the ability to synthesize prodiginine by cocultivation with siderophore producers or the addition of iron. Therefore, we conclude that SspA-regulated prodiginine biosynthesis is due to decreased siderophore levels and iron deficiency. We further show that the iron homeostasis master regulator Fur is also essential for pig transcription and prodiginine biosynthesis. Overall, our results suggest that SspA indirectly regulates the biosynthesis of prodiginine, which is mediated by the siderophore-dependent iron uptake pathway.IMPORTANCE The red-pigmented prodiginines are attracting increasing interest due to their broad biological activities. As with many secondary metabolites, the biosynthesis of prodiginines is regulated by both environmental and physiological factors. At present, studies on the regulation of prodiginine biosynthesis are mainly restricted to Serratia and Streptomyces species. This work focused on the regulatory mechanism of prodiginine biosynthesis in Pseudoalteromonas sp. R3. We found that stringent starvation protein A (SspA) positively regulates prodiginine biosynthesis via affecting the siderophore-dependent iron uptake pathway. The connections among SspA, iron homeostasis, and prodiginine biosynthesis were investigated. These findings uncover a novel regulatory mechanism for prodigiosin biosynthesis.