55.1, a gene of unknown function of phage T4, impacts on Escherichia coli folate metabolism and blocks DNA repair by the NER

Article Article scientifique Article 55.1, a gene of unknown function of phage T4, impacts on Escherichia coli folate metabolism and blocks DNA repair by the NER eng 2011 author Mattenberger Yves Benoît 502615 author Mattson Shawn 712247 author Metrailler Johann 593042 author Silva Filo 23504 author Belin Dominique 24771 1406-1421 10.1111/j.1365-2958.2011.07897.x 22029793 0950-382X Phage T4, the archetype of lytic bacterial viruses, needs only 62 genes to propagate under standard laboratory conditions. Interestingly, the T4 genome contains more than 100 putative genes of unknown function, with few detectable homologues in cellular genomes. To characterize this uncharted territory of genetic information, we have identified several T4 genes that prevent bacterial growth when expressed from plasmids under inducible conditions. Here, we report on the various phenotypes and molecular characterization of 55.1, one of the genes of unknown function. High-level expression from the arabinose-inducible P(BAD) promoter is toxic to the bacteria and delays the intracellular accumulation of phage without affecting the final burst size. Low-level expression from T4 promoter(s) renders bacteria highly sensitive to UV irradiation and hypersensitive to trimethoprim, an inhibitor of dihydrofolate reductase. The delay in intracellular phage accumulation requires UvsW, a T4 helicase that is also a suppressor of 55.1-induced toxicity and UV sensitivity. Genetic and biochemical experiments demonstrate that gp55.1 binds to FolD, a key enzyme of the folate metabolism and suppressor of 55.1. Finally, we show that gp55.1 prevents the repair of UV-induced DNA photoproducts by the nucleotide excision repair (NER) pathway through interaction with the UvrA and UvrB proteins. Bacteriophage T4/genetics/metabolism DNA Damage/radiation effects DNA Repair/radiation effects Escherichia coli/genetics/metabolism/radiation effects Escherichia coli Proteins/genetics/metabolism Folic Acid/metabolism Gene Expression Ultraviolet Rays Viral Proteins/genetics/metabolism Dewey 616.07 137 Département de pathologie et immunologie 21F false 138 Translocation des protéines à travers les membranes 169 Molecular microbiology 82 6 418a58ba-af1d-4453-96dc-fd09d0566684 Article (Published version) Public 55.1_molmic.pdf 1574075 application/pdf 4d7acfbb-151d-4cad-80ed-338ed98f2458 Article (Published version) Public 55.1_molmic_supmat.pdf 1158012 application/pdf openAccess Faculté de médecine / Section de médecine fondamentale / Département de pathologie et immunologie

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55.1, a gene of unknown function of phage T4, impacts on Escherichia coli folate metabolism and blocks DNA repair by the NER	Molecular microbiology			2011	679	1,128

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Mattson, Shawn