Unknown,Transcriptomics,Genomics,Proteomics

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RNA-Seq analysis of Pseudomonas aeruginosa PAO1 cells infected with PhiKZ phage

ABSTRACT: Pseudomonas aeruginosa bacteriophage PhiKZ is the type representative of the M-bM-^@M-^XgiantM-bM-^@M-^Y phage genus with unusually large virions and genomes. By unraveling the transcriptional map of the 280 kb genome to single-nucleotide resolution, we show that it encodes 369 genes organized in 134 operons, 20% more than originally annotated. Early transcription is initiated from 28 highly conserved AT-rich promoters distributed over the PhiKZ genome, all located on the same strand. Transcription of middle and late genes is dependent on protein synthesis and mediated by very poorly conserved middle (6) and late (16) promoters. As a result of massive PhiKZ transcription, halfway through infection only 1.5% of all mRNAs in the infected cell remain bacterial. Unique to PhiKZ is its ability to complete its infection in complete absence of bacterial RNA polymerase (RNAP) enzyme activity. Its transcription is performed by the consecutive action of two PhiKZ-encoded, non-canonical RNAPs, one of which is packed within the virion. This unique, rifampicin-resistant transcriptional machinery is conserved among giant viruses, seems to function without auxiliary factors and might have its origin preceding the split between Gram-positive and Gram-negative bacteria. Construction of transcription maps for the PhiKZ phage and analysis of differential expression of host and phage genes using RNA-Seq data from samples taken in duplicate at 0, 5, 10, 15, and 35 minutes into infection.

ORGANISM(S): Pseudomonas aeruginosa

SUBMITTER: Bob Blasdel

PROVIDER: E-GEOD-58494 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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RNA-Seq analysis of Pseudomonas aeruginosa PAO1 cells infected with PhiKZ phage

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