1.E.11 The φ11 Holin (φ11 Holin) Family

See 1.E for a generalized description of Holins.

The pneumococcal EJ-1 phage holin (EJh) is a hydrophobic peptide (85 aas) with 2 putative TMSs displaying lethal inner membrane disruptive activity. The synthetic N-terminal TMS flanked by its N-terminal positively charged residues folds into a transmembrane α-helix that increases the membrane permeability. Oligomeric channels of various sizes form depending on the peptide to lipid ratio (Haro et al., 2003). By atomic force microscopy, peptide-induced membrane holes can be seen.

This family belongs to the Holin I Superfamily.



Bon, J., N. Mani, and R.K. Jayaswal. (1997). Molecular analysis of lytic genes of bacteriophage 80 alpha of Staphylococcus aureus. Can. J. Microbiol. 43: 612-616.

Cerca, N., R. Oliveira, and J. Azeredo. (2007). Susceptibility of Staphylococcus epidermidis planktonic cells and biofilms to the lytic action of staphylococcus bacteriophage K. Lett Appl Microbiol 45: 313-317.

Curtin, J.J. and R.M. Donlan. (2006). Using bacteriophages to reduce formation of catheter-associated biofilms by Staphylococcus epidermidis. Antimicrob. Agents Chemother. 50: 1268-1275.

Diaz, E., M. Munthali, H. Lunsdorf, J.V. Holtje, and K.N. Timmis. (1996). The two-step lysis system of pneumococcal bacteriophage EJ-1 is functional in gram-negative bacteria: triggering of the major pneumococcal autolysin in Escherichia coli. Mol. Microbiol. 19: 667-681.

Haro, A., M. Vélez, E. Goormaghtigh, S. Lago, J. Vázquez, D. Andreu, and M. Gasset. (2003). Reconstitution of holin activity with a synthetic peptide containing the 1-32 sequence region of EJh, the EJ-1 phage holin. J. Biol. Chem. 278: 3929-3936.

Loessner, M.J., S. Gaeng, G. Wendlinger, S.K. Maier, and S. Scherer. (1998). The two-component lysis system of Staphylococcus aureus bacteriophage Twort: a large TTG-start holin and an associated amidase endolysin. FEMS Microbiol. Lett. 162: 265-274.

Martínez, V., P. García, J.L. García, and M.A. Prieto. (2011). Controlled autolysis facilitates the polyhydroxyalkanoate recovery in Pseudomonas putida KT2440. Microb Biotechnol 4: 533-547.

Seal, B.S., D.E. Fouts, M. Simmons, J.K. Garrish, R.L. Kuntz, R. Woolsey, K.M. Schegg, A.M. Kropinski, H.W. Ackermann, and G.R. Siragusa. (2011). Clostridium perfringens bacteriophages ΦCP39O and ΦCP26F: genomic organization and proteomic analysis of the virions. Arch Virol 156: 25-35.

Song, J., F. Xia, H. Jiang, X. Li, L. Hu, P. Gong, L. Lei, X. Feng, C. Sun, J. Gu, and W. Han. (2016). Identification and characterization of HolGH15: the holin of Staphylococcus aureus bacteriophage GH15. J Gen Virol 97: 1272-1281.


TC#NameOrganismal TypeExample

Holin 145 (Bon et al. 1997)

Staphylococcus phage φ11

Holin (145 aas)


Holin of 100 aas and 2 TMSs


Holin of Atopobium parvulum

1.E.11.1.2HolinLactococcus phage Tuc 2009Holin (88 aas)

Holin of 85 aas, Ejh (Diaz et al. 1996).  A synthetic peptide based on Ejh has been reconstituted and shown to be active (Haro et al. 2003).  Ejh has been used to promote release of polyhydroxyalkanoate granules from bacterial cells (Martínez et al. 2011).

EJh of Streptococcus pneumoniae phage EJ-1

Holin EJh (85 aas)




Holin of of Streptococcus pyongenes


Holin HolTW (Loessner et al. 1998).

Firmicute viruses

Holin HolTS of Staphylococcus phage TWORT


Putative holin


Putative holin of Listeria innocua


Putative holin; phage phiLC3 holin family


Putative holin of Streptococcus sanguinis


Holin (Orf33) of 167 aas from Stahylococcus phage K. Phage K lysis differentially affects planctonic and biofilm cells (Cerca et al. 2007; Curtin and Donlan 2006).  95% identical to HolGH15 of phage GH15 of S. aureus which has broad host range antibacterial activity against many pathogens (Song et al. 2016).

Firmicute viruses

Orf33 of Stahylococcus phage K; HolGH15 of Staphylococcus phage GH15


Holin of the phage phi LC3 family of 91 aas and 2 TMSs


Holin of Collinsella aerofaciens


TC#NameOrganismal TypeExample

Holin of Clostridium phage phiCP390 (Seal et al. 2011).  This holin is identical to the holin of phage phiCP26F (gp23; F2VHY0).


Holin of Clostridium perfringens phage PhiCP390


Putative holin


Putative holin of Clostridium perfringens


Putative holin


Putative holin of Geobacillus kustophilus


Uncharacterized holin phage phi LC3 of 63 aas and 2 TMSs.

Putative holin of Ruminiclostridium papyrosolvens


Holin of 83 aas and 2 TMSs, Phage_holin_1.

Holin of a eubacterium


TC#NameOrganismal TypeExample

Putative holin of 49 aas and 1 TMS.  TMS 1 corresponds to TMS 2 in the holins of TC subfamilies 1.E.11.1 and 1.E.11.2.


Putative holin of Pseudomonas putida


Uncharacterized protein of 60 aas and 1 TMS

UP of Chromatiales bacterium 21-64-14 (mine drainage metagenome)


Uncharacterized protein of 62 aas and 1 TMS

UP of Chromatium okenii


Putative holin of 50 aas and 1 TMS


Putative holin of Pseudomonas syringae


Putative uncharacterized holin of 32 aas and 1 TMS.

UP of Halomonas sp. HL-48 (microbial mat metagenome)


Uncharacterized protein of 48 aas and 1 TMS.

UP of Marinobacter sp. T13-3 (gas well metagenome)


Uncharacterized protein of 63 aas and 1 TMS (N-terminal)

UP of Mangrovitalea sediminis


Uncharacterized protein of 41 aas and 1 TMS

UP of Nitrincola nitratireducens


Uncharacterized protein of 48 aas and 1 TMS.

UP of Halioglobus sediminis


Uncharacterized protein of 49 aas and 1 TMS

UP of Alcanivorax nanhaiticus


Uncharacterized protein of 54 aas and 1 TMS

UP of Gynuella sunshinyii