SPP 2330

GROUP COMMICHAU / Project CO 1139/6-1

Functional dissection of the Bacillus subtilis SPβ prophage lysogeny-lysis decision system and characterization of a novel SPβ defense system
The temperate phage SPβ infects the endospore-forming Gram-positive bacterium Bacillus subtilis and resides as a prophage in its genome. Phages of the SPβ group use a peptide-based communication system (termed the “arbitrium” system) to coordinate lysis-lysogeny decisions. Recently, we have identified the master repressor of SPβ and a factor that acts downstream of the repressor and is critical for the activation of the lytic cycle. Although many additional components of the lysis-lysogeny decision system have already been identified, it is unclear how the lysogenic cycle, particularly in the case of the phage SPβ, is activated. By pursuing genetic, biochemical, and structural studies, we are elucidating the molecular details of the lysis-lysogeny decision system of the temperate phage SPβ. We also study a putative SPβ defense system that is encoded on an Escherichia coliB. subtilis shuttle vector.

Figure 1: SPβ is a prophage that is present in many B. subtilis strains. (A) SPβ is a host-benefitting trait because the bacteria carrying the prophage produce the glycopeptide sublancin that kill SPβ-free B. subtilis strains and other bacteria. (B) MrpR is the master repressor of SPβ that recognizes the SPBR element in the prophage genome.

Principal Investigator(s)

Prof. Dr. Fabian M. Commichau
Universität Hohenheim
Institute for Biology, FG Molecular Microbiology

E-Mail: fabian.commichau@uni-hohenheim.de
Homepage: https://mikrobiologie.uni-hohenheim.de

PhD student(s)

Publications

  • Kohm K, Jalomo-Khayrova E, Krüger A, Basu S, Steinchen W, Bange G, Frunzke J, Hertel R, Commichau FM, Czech L (2023) Structural and functional characterization of MrpR, the master repressor of the Bacillus subtilis prophage SPb. Nucleic Acids Res 51: 9452-9474.
  • Kohm K, v. Clanner A, Hertel R, Commichau FM (2024) Closely related and yet special – how SPb family phages control lysis-lysogeny decisions. Trends Microbiol In press.