Viral terminal protein directs early organization of phage DNA replication at the bacterial nucleoid

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 107; no. 38; pp. 16548 - 16553
• Main Authors: Muñoz-Espín, Daniel, Holguera, Isabel, Ballesteros-Plaza, David, Carballido-López, Rut, Salas, Margarita
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences 21.09.2010; National Acad Sciences
• Subjects: Adenoviruses; Bacillus Phages - genetics; Bacillus Phages - physiology; Bacillus subtilis; Bacillus subtilis - genetics; Bacillus subtilis - metabolism; Bacillus subtilis - virology; Bacterial proteins; Bacteriophage PRD1 - genetics; Bacteriophage PRD1 - physiology; Bacteriophages; Binding sites; Biological Sciences; Cytoskeleton; Data processing; Deoxyribonucleic acid; DNA; DNA biosynthesis; DNA polymerase; DNA replication; DNA Replication - genetics; DNA Replication - physiology; DNA, Viral - biosynthesis; DNA, Viral - genetics; DNA-directed DNA polymerase; DNA-Directed DNA Polymerase - metabolism; E coli; Escherichia coli; Escherichia coli - genetics; Escherichia coli - metabolism; Escherichia coli - virology; Genes, Bacterial; Genes, Viral; Genomes; Infections; Life Sciences; Models, Biological; Models, Molecular; Molecular structure; Mutation; Nucleoids; Phages; Protein Structure, Tertiary; Proteins; Recombinant Fusion Proteins - genetics; Recombinant Fusion Proteins - metabolism; Replication; Terminal protein; Viral Proteins - chemistry; Viral Proteins - genetics; Viral Proteins - metabolism; Virus Replication - genetics; Virus Replication - physiology; Viruses; DNA polymerase; LINEAR DNA; Bacillus subtilis; ADENOVIRUS DNA; MREB; ESCHERICHIA-COLI; FUNCTIONAL DOMAIN; phage phi 29; DNA-binding; bacterial cytoskeleton; ACTIN-LIKE PROTEINS; BACILLUS-SUBTILIS; CHROMOSOME SEGREGATION; COILED-COIL; RNA-POLYMERASE
• ISSN: 0027-8424; 1091-6490; 1091-6490
• DOI: 10.1073/pnas.1010530107

The mechanism leading to protein-primed DNA replication has been studied extensively in vitro. However, little is known about the in vivo organization of the proteins involved in this fundamental process. Here we show that the terminal proteins (TPs) of phages φ29 and PRD1, infecting the distantly related bacteria Bacillus subtilis and Escherichia coli, respectively, associate with the host bacterial nucleoid independently of other viral-encoded proteins. Analyses of phage φ29 revealed that the TP N-terminal domain (residues 1—73) possesses sequence-independent DNA-binding capacity and is responsible for its nucleoid association. Importantly, we show that in the absence of the TP N-terminal domain the efficiency of φ29 DNA replication is severely affected. Moreover, the TP recruits the phage DNA polymerase to the bacterial nucleoid, and both proteins later are redistributed to enlarged helix-like structures in an MreB cytoskeleton-dependent way. These data disclose a key function for the TP in vivo: organizing the early viral DNA replication machinery at the cell nucleoid.