Lavysh, D.; Mekler, V.; Klimuk, E.; Severinov, K. Regulation of Gene Expression of phiEco32-like Bacteriophage 7-11. Viruses2022, 14, 555.
Lavysh, D.; Mekler, V.; Klimuk, E.; Severinov, K. Regulation of Gene Expression of phiEco32-like Bacteriophage 7-11. Viruses 2022, 14, 555.
Lavysh, D.; Mekler, V.; Klimuk, E.; Severinov, K. Regulation of Gene Expression of phiEco32-like Bacteriophage 7-11. Viruses2022, 14, 555.
Lavysh, D.; Mekler, V.; Klimuk, E.; Severinov, K. Regulation of Gene Expression of phiEco32-like Bacteriophage 7-11. Viruses 2022, 14, 555.
Abstract
Salmonella enterica serovar Newport bacteriophage 7-11 shares 41 homologous ORFs with Escherichia coli phage phiEco32 and both phages encode a protein similar to bacterial RNA polymerase promoter specificity subunit. Here, we investigated the temporal pattern of 7-11 gene expression during the infection and compared it to the previously determined transcription strategy of phiEco32. Using primer extension and in vitro transcription assays we identified eight promoters recognized by host RNA polymerase holoenzyme containing 7-11 subunit SaPh711_gp47. These promoters are characterized by a bipartite consensus GTAAtg-(16)-aCTA and are located upstream of late phage genes. While dissimilar from single-element middle and late promoters of phiEco32 recognized by holoenzyme formed by the phi32_gp36 factor, the 7-11 late promoters are located at genome positions similar to those of phiEco32 middle and late promoters. Two early 7-11 promoters are recognized by RNA polymerase holoenzyme containing host primary σ70 factor. Unlike the case of phiEco32, no shut off of σ70-dependent transcription is observed during 7-11 infection and there are no middle promoters. These differences can be explained by the fact that phage 7-11 does not encode a homologue of phi32_gp79, an inhibitor of host and early phage transcription and an activator of transcription by the phi32_gp36-holoenzyme.
Keywords
bacteriophage; alternative sigma factor; transcription regulation
Subject
Biology and Life Sciences, Immunology and Microbiology
Copyright:
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