It is proposed to continue the genetic analysis of the P2 - P4 system consisting of two temperate bacteriophages, P2 (or a P2 relative) and P4, and their common bacterial host, Escherichia coli. In this system P2 (or its relative) serves as """"""""helper"""""""" for its """"""""satellite"""""""" P4. The main aim is to further elucidate the genetic control mechanisms that couple gene expression for satellite and helper. These include mutual derepression and transactivation. Investigations of other interactions characteristic for this system are also planned. Specifically the proposal concerns: (1) studies of P4 mutants able to use as helper a P2-related prophage not accessible to wild type P4, to identify the critical interaction for this helper - P4 combination; (2) studies of mutations affecting phage head size determination in the P2 - P4 system, especially further analysis of """"""""shrink resistant"""""""" P2 mutants, also (3) related studies of P4 - plasmid interactions leading to the formation of transducing """"""""phasmids""""""""; (4) a search for P2 mutants deficient in reciprocal transactivation of P4; (5) further studies of the effects fo mutation in rpoA (the gene for he Alpha subunit of the bacterial RNA polymerase) on gene expression in the P2 - P4 systems; (6) studies of bacterial filamentation caused by P4 mutants present as prophage or infecting phage; (7) further studies of P2 cox mutants and their effects on derepression and recombination; (8) further studies of suppresor mutations that compensate forlack of an early P2 gene function and; (9) a search for P4 related genomes and their eventual analysis.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI004043-24
Application #
3124167
Study Section
(MG)
Project Start
1979-01-01
Project End
1986-12-31
Budget Start
1985-01-01
Budget End
1985-12-31
Support Year
24
Fiscal Year
1985
Total Cost
Indirect Cost
Name
University of Iowa
Department
Type
Schools of Medicine
DUNS #
041294109
City
Iowa City
State
IA
Country
United States
Zip Code
52242
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Forti, F; Polo, S; Lane, K B et al. (1999) Translation of two nested genes in bacteriophage P4 controls immunity-specific transcription termination. J Bacteriol 181:5225-33
Nilssen, O; Six, E W; Sunshine, M G et al. (1996) Mutational analysis of the bacteriophage P4 capsid-size-determining gene. Virology 219:432-42
Haggard-Ljungquist, E; Jacobsen, E; Rishovd, S et al. (1995) Bacteriophage P2: genes involved in baseplate assembly. Virology 213:109-21
Six, E W; Sunshine, M G; Williams, J et al. (1991) Morphopoietic switch mutations of bacteriophage P2. Virology 182:34-46
Inouye, S; Sunshine, M G; Six, E W et al. (1991) Retronphage phi R73: an E. coli phage that contains a retroelement and integrates into a tRNA gene. Science 252:969-71
Sunshine, M; Six, E (1986) sub, a host mutation that specifically allows growth of replication-deficient gene B mutants of coliphage P2. Mol Gen Genet 204:359-61