Bacteriophage ΦKZ (PhiKZ) is the archetype of a family of massive bacterial viruses. It is considered to have therapeutic potential as its host, Pseudomonas aeruginosa, is an opportunistic, intrinsically antibiotic resistant, pathogen that kills tens of thousands worldwide each year. ΦKZ is an incredibly interesting virus, expressing many systems that the host already possesses. On infection, it forms a 'nucleus', erecting a barrier around its genome to exclude host endonucleases and CRISPR-Cas systems. ΦKZ infection is independent of the host transcriptional apparatus. It expresses two different multi-subunit RNA polymerases (RNAPs): the virion RNAP (vRNAP) is injected with the viral DNA during infection to transcribe early genes, including those encoding the non-virion RNAP (nvRNAP), which transcribes all further genes. ΦKZ nvRNAP is formed by four polypeptides thought to represent homologues of the eubacterial β/β' subunits, and a fifth with unclear homology, but essential for transcription. We have resolved the structure of ΦKZ nvRNAP to better than 3.0 Å, shedding light on its assembly, homology, and the biological role of the fifth subunit: it is an embedded, integral member of the complex, the position, structural homology and biochemical role of which imply that it has evolved from an ancestral homologue to σ-factor.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8287921PMC
http://dx.doi.org/10.1093/nar/gkab539DOI Listing

Publication Analysis

Top Keywords

Φkz nvrnap
8
Φkz
5
structure bacteriophage
4
bacteriophage phikz
4
phikz non-virion
4
non-virion rna
4
rna polymerase
4
polymerase bacteriophage
4
bacteriophage Φkz
4
Φkz phikz
4

Similar Publications

Structure of the Bacteriophage PhiKZ Non-virion RNA Polymerase Transcribing from its Promoter p119L.

J Mol Biol

September 2024

Shenzhen MSU-BIT University, 1 International University Park Road, Dayun New Town, Longgang District, Shenzhen, Guangdong Province 518172, People's Republic of China. Electronic address:

Article Synopsis
  • * ΦKZ creates an internal "nucleus" to protect its genome from host immune responses and uses a unique RNA polymerase (nvRNAP) for gene transcription.
  • * The structure of ΦKZ nvRNAP has been resolved, revealing important insights into its transcription process and how it compares to traditional eubacterial RNA polymerases and the nvRNAP of another virus, AR9.
View Article and Find Full Text PDF

A nucleus-like structure composed of phage-encoded proteins and containing replicating viral DNA is formed in cells infected by jumbo bacteriophage phiKZ. The PhiKZ genes are transcribed independently from host RNA polymerase (RNAP) by two RNAPs encoded by the phage. The virion RNAP (vRNAP) transcribes early viral genes and must be injected into the cell with phage DNA.

View Article and Find Full Text PDF
Article Synopsis
  • Host-pathogen interactions (HPIs) are crucial for understanding how infections establish and progress; traditional methods focus on small pathogens but can be limiting.
  • The researchers introduced co-fractionation mass spectrometry (SEC-MS) to analyze HPIs from two large phages, revealing over 6000 unique interactions and insights into fundamental viral mechanisms.
  • To enhance accessibility, they created PhageMAP, an online tool for visualizing and querying these interactions, aimed at advancing the study of host-pathogen dynamics.
View Article and Find Full Text PDF

Structural basis of template strand deoxyuridine promoter recognition by a viral RNA polymerase.

Nat Commun

June 2022

Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX, 77555-0647, USA.

Recognition of promoters in bacterial RNA polymerases (RNAPs) is controlled by sigma subunits. The key sequence motif recognized by the sigma, the -10 promoter element, is located in the non-template strand of the double-stranded DNA molecule ~10 nucleotides upstream of the transcription start site. Here, we explain the mechanism by which the phage AR9 non-virion RNAP (nvRNAP), a bacterial RNAP homolog, recognizes the -10 element of its deoxyuridine-containing promoter in the template strand.

View Article and Find Full Text PDF

Bacteriophage ΦKZ (PhiKZ) is the archetype of a family of massive bacterial viruses. It is considered to have therapeutic potential as its host, Pseudomonas aeruginosa, is an opportunistic, intrinsically antibiotic resistant, pathogen that kills tens of thousands worldwide each year. ΦKZ is an incredibly interesting virus, expressing many systems that the host already possesses.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!