1.E.10 The Bacillus subtilis φ29 Holin (φ29 Holin) Family

Phage φ29 gene 14 encodes the late protein GP14 which is required for phage φ29-promoted host cell lysis. When expressed in E. coli, it leads to cell death without lysis. When expressed together with phage φ29 lysozyme or an unrelated murein-degrading enzyme, cell lysis is also observed. Thus, protein 14 is a nonspecific holin in the cytoplasmic membrane of B. subtilis. It is identical to the phage PZA lysis protein and nearly identical to the phage B103 lysis protein. It is 34% identical to the phage GA-1 holin.

This family belongs to the Holin IV Superfamily .



Shi, Y., Y. Yan, W. Ji, B. Du, X. Meng, H. Wang, and J. Sun. (2012). Characterization and determination of holin protein of Streptococcus suis bacteriophage SMP in heterologous host. Virol J 9: 70.

Steiner, M., W. Lubitz, and U. Bläsi. (1993). The missing link in phage lysis of gram-positive bacteria: gene 14 of Bacillus subtilis phage phi 29 encodes the functional homolog of lambda S protein. J. Bacteriol. 175: 1038-1042.

Tedin, K., A. Resch, M. Steiner, and U. Bläsi. (1995). Dual translational start motif evolutionarily conserved in the holin gene of Bacillus subtilis phage phi 29. Virology 206: 479-484.


TC#NameOrganismal TypeExample

Lysis holin protein (late protein GP14) (Tedin et al. 1995).

Bacillus phage f29

GP14 (131 aas; spP11188)


Pneumococcal phage SV1 holin 1.

Firmicute viruses

Pneumococcal phage SV1 holin 1


Holin HolSMP (Orf43) (Shi et al. 2012).

Firmicute viruses

HolSMP of Streptococcus suis phage SMP


Anti-holin (gene 14) of 132 aas and 2 TMSs.  It determines the precise timing of host cell lysis.

Antiholin of Bacillus phage B103 (Bacteriophage B103)