Project description:After the attachment of the lytic phage T4 to Escherichia coli cells, 1% E. coli cells showed an approximately 40-fold increase in mutant frequency. They were designated as mutator A global transcriptome analysis using microarrays was conducted to determine the difference between parental strain and mutators, and the host responce after adsorption of the phage and the ghost.
Project description:Here, we investigated the impact of Stx2 phage carriage on Escherichia coli (E. coli) K-12 MG1655 host gene expression. Using quantitative RNA-seq analysis, we compared the transcriptome of naïve MG1655 and the lysogens carrying the Stx2 phage of the 2011 E. coli O104:H4 outbreak strain or of the E. coli O157:H7 strain PA8, which share high degree of sequence similarity.
Project description:References:
1. Xiaomei Zhu, Lan Yin, Leroy Hood, David Galas and Ping Ao, Efficiency, Robustness and Stochasticity of Gene Regulatory networks in Systems biology: Lambda switch as a working example, 2006.
2. Adam Arkin, John Ross and Harley H. McAdams, Stochastic kinetic analysis of developmental pathway bifurcation in phage lambda-infected Escherichia coli cells, 1998, Genetics, 149: 1633-1648.
3. GenBank sequence: NC_001416 is the whole genome sequence of phage lambda.
Project description:Retrons are prokaryotic genetic elements involved in anti-phage defense and consist of a non-coding RNA, a reverse transcriptase (RT), and various effector proteins. Retron-Eco7 (previously known as Retron-Ec78) from Escherichia coli encodes two effector proteins (a PtuA ATPase and a PtuB nuclease) and degrades host tRNATyr upon phage infection, thereby protecting host cells against invading phages. However, its defense mechanism remains elusive. Here, we report the cryo-electron microscopy structures of the Retron-Eco7 complex, comprising the RT, multicopy single-stranded DNA (msDNA), PtuA, and PtuB. The Retron-Eco7 structure reveals that the RT–msDNA complex associates with two PtuA–PtuB complexes, potentially inhibiting their nuclease activity and suppressing bacterial growth arrest prior to phage infection. Furthermore, we found that a phage-encoded D15 nuclease acts as a trigger for the Retron-Eco7 system, cleaving the msDNA bound to the complex and facilitating the dissociation of PtuA–PtuB from RT–msDNA. Our data indicate that msDNA cleavage by D15 is the initial step required for the specific cleavage of host tRNATyr by the PtuA–PtuB nuclease, which leads to abortive infection. Overall, this study provides mechanistic insights into the Retron-Eco7 system and highlights the diversity of prokaryotic anti-phage defense mechanisms.
Project description:After the attachment of the lytic phage T4 to Escherichia coli cells, 1% E. coli cells showed an approximately 40-fold increase in mutant frequency. They were designated as mutator A global transcriptome analysis using microarrays was conducted to determine the difference between parental strain and mutators.
Project description:This project is about the proteomic and phosphoproteomic analyses of phage JSS1 or JSS1Δ004 infected Salmonella strains. AD032TQ is proteomes of phage JSS1 or JSS1Δ004 infected S. enterica serovar Cerro 87. AD032TPST is phosphoproteome of phage JSS1 or JSS1Δ004 infected S. enterica serovar Cerro 87. AE065TQ is proteomes of phage JSS1 or JSS1Δ004 infected CX1, a S. enterica serovar Cerro 87 dndFGH deficient strain, harboring a plasmid expressing DndFGH from Escherichia coli B7A. AE065TPST is phosphoproteome of phage JSS1 or JSS1Δ004 infected CX1 harboring a plasmid expressing DndFGH from E. coli B7A.
Project description:This project is about the proteomic and phosphoproteomic analyses of phage JSS1 or JSS1Δ004 infected Salmonella strains. AD032TQ is proteomes of phage JSS1 or JSS1Δ004 infected S. enterica serovar Cerro 87. AD032TPST is phosphoproteome of phage JSS1 or JSS1Δ004 infected S. enterica serovar Cerro 87. AE065TQ is proteomes of phage JSS1 or JSS1Δ004 infected CX1, a S. enterica serovar Cerro 87 dndFGH deficient strain, harboring a plasmid expressing DndFGH from Escherichia coli B7A. AE065TPST is phosphoproteome of phage JSS1 or JSS1Δ004 infected CX1 harboring a plasmid expressing DndFGH from E. coli B7A.