Characterization of a unique repression system present in arbitrium phages of the SPbeta family

Cell Host Microbe. 2023 Nov 21:S1931-3128(23)00453-5. doi: 10.1016/j.chom.2023.11.003. Online ahead of print.ABSTRACTArbitrium-coding phages use peptides to communicate and coordinate the decision between lysis and lysogeny. However, the mechanism by which these phages establish lysogeny remains unknown. Here, focusing on the SPbeta phage family's model phages phi3T and SPβ, we report that a six-gene operon called the "SPbeta phages repressor operon" (sro) expresses not one but two master repressors, SroE and SroF, the latter of which folds like a classical phage integrase. To promote lysogeny, these repressors bind to multiple sites in the phage genome. SroD serves as an auxiliary repressor that, with SroEF, forms the repression module necessary for lysogeny establishment and maintenance. Additionally, the proteins SroABC within the operon are proposed to constitute the transducer module, connecting the arbitrium communication system to the activity of the repression module. Overall, this research sheds light on the intricate and specialized repression system employed by arbitrium SPβ-like phages in making lysis-lysogeny decisions.PMID:38035880 | DOI:10.1016/j.chom.2023.11.003

Source: Cell Host and Microbe - November 30, 2023 Category: Microbiology Authors: Aisling Brady Elena Cabello-Yeves Francisca Gallego Del Sol Cora Chmielowska Javier Manche ño-Bonillo Sara Zamora-Caballero Shira Bendori Omer Manuela Torres-Puente Avigdor Eldar Nuria Quiles-Puchalt Alberto Marina Jos é R Penadés Source Type: research