TCDB is operated by the Saier Lab Bioinformatics Group

1.M.1 The Rz/Rz1 Spanin1 (Rz(1)) Family 

Bacteriophage lambda has four adjacent genes, S, R, Rz and Rz1, dedicated to host cell lysis. S encodes the holin and antiholin and R encodes the endolysin while Rz1 and Rz are an outer membrane lipoprotein and a type II signal anchor protein.  Together they comprise a spanin. The Rz-Rz1 complex spans the periplasm ane carries out the final step in the process of host lysis. Endolysin-mediated degradation of the cell wall is a prerequisite for conformational changes in the Rz-Rz1 complex leading to the juxtaposition and fusion of the two membranes. Fusion removes the last physical barrier to efficient release of progeny virions (Berry et al. 2008; Rajaure et al. 2015).  The lambda Rz and Rz1 lysis genes are remarkable in that Rz1, encoding the outer membrane lipoprotein, is completely embedded in the +1 register within Rz, which itself encodes the inner membrane protein (Summer et al. 2007; Berry et al. 2012; Berry et al. 2008).

References associated with 1.M.1 family:

Berry, J., E.J. Summer, D.K. Struck, and R. Young. (2008). The final step in the phage infection cycle: the Rz and Rz1 lysis proteins link the inner and outer membranes. Mol. Microbiol. 70: 341-351. 18713319
Berry, J., M. Rajaure, T. Pang, and R. Young. (2012). The spanin complex is essential for lambda lysis. J. Bacteriol. 194: 5667-5674. 22904283
Khakhum, N., U. Yordpratum, A. Boonmee, U. Tattawasart, J.L. Rodrigues, and R.W. Sermswan. (2016). Identification of the Burkholderia pseudomallei bacteriophage ST79 lysis gene cassette. J Appl Microbiol. [Epub: Ahead of Print] 27038077
Rajaure, M., J. Berry, R. Kongari, J. Cahill, and R. Young. (2015). Membrane fusion during phage lysis. Proc. Natl. Acad. Sci. USA 112: 5497-5502. 25870259
Summer, E.J., J. Berry, T.A. Tran, L. Niu, D.K. Struck, and R. Young. (2007). Rz/Rz1 lysis gene equivalents in phages of Gram-negative hosts. J. Mol. Biol. 373: 1098-1112. 17900620