The ''Bacillus subtilis'' φ29 Holin (φ29 Holin) Family (TC# 1.E.10) is a group of
transporters belonging to the
Holin Superfamily IV The Holin superfamily IV is a superfamily of integral membrane transport proteins. It is one of the seven different holin superfamilies in total.
The Holin superfamily IV includes the TC families:
1.E.10- The ''Bacillus subtilis'' φ29 Holin (φ ...
. A representative list of members belonging to the φ29 holin family can be found in the Transporter Classification Database.
The phage φ29 gene 14 encodes the protein GP14 (TC# 1.E.10.1.1) which is required for phage φ29-promoted host cell lysis. When expressed in ''
E. coli
''Escherichia coli'' (),Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. also known as ''E. coli'' (), is a Gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus ''Escher ...
'', it leads to
cell death without
lysis
Lysis ( ) is the breaking down of the membrane of a cell, often by viral, enzymic, or osmotic (that is, "lytic" ) mechanisms that compromise its integrity. A fluid containing the contents of lysed cells is called a ''lysate''. In molecular bio ...
. When expressed together with phage φ29
lysozyme or an unrelated
murein-degrading enzyme,
cell lysis is also observed. Thus, GP14 is a nonspecific holin in the cytoplasmic membrane of ''
B. subtilis
''Bacillus subtilis'', known also as the hay bacillus or grass bacillus, is a Gram-positive, catalase-positive bacterium, found in soil and the gastrointestinal tract of ruminants, humans and marine sponges. As a member of the genus ''Bacillus' ...
.'' 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.
See also
*
Holin
*
Lysin
Lysins, also known as endolysins or murein hydrolases, are hydrolytic enzymes produced by bacteriophages in order to cleave the host's cell wall during the final stage of the lytic cycle. Lysins are highly evolved enzymes that are able to target ...
*
Transporter Classification Database
References
Holins
Protein families
{{Membrane-protein-stub