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<entry dataset="Swiss-Prot" created="1989-07-01" modified="2021-04-07" version="95" xmlns="http://uniprot.org/uniprot">
    <accession>P09962-2</accession>
    <name>HOLIN_BPP22</name>
    <protein>
        <recommendedName>
            <fullName evidence="2">Isoform Holin of Antiholin</fullName>
        </recommendedName>
        <alternativeName>
            <fullName evidence="2">Lysis inhibitor 13-108</fullName>
        </alternativeName>
    </protein>
    <gene>
        <name type="primary">13</name>
    </gene>
    <organism>
        <name type="scientific">Salmonella phage P22</name>
        <name type="synonym">Bacteriophage P22</name>
        <dbReference type="NCBI Taxonomy" id="10754"/>
        <lineage>
            <taxon>Viruses</taxon>
            <taxon>Duplodnaviria</taxon>
            <taxon>Heunggongvirae</taxon>
            <taxon>Uroviricota</taxon>
            <taxon>Caudoviricetes</taxon>
            <taxon>Caudovirales</taxon>
            <taxon>Podoviridae</taxon>
            <taxon>Lederbergvirus</taxon>
        </lineage>
    </organism>
    <organismHost>
        <name type="scientific">Salmonella typhimurium</name>
        <dbReference type="NCBI Taxonomy" id="90371"/>
    </organismHost>
    <reference key="1">
        <citation type="journal article" date="1985" name="Virology" volume="143" first="280" last="289">
            <title>Phage P22 lysis genes: nucleotide sequences and functional relationships with T4 and lambda genes.</title>
            <authorList>
                <person name="Rennell D."/>
                <person name="Poteete A.R."/>
            </authorList>
            <dbReference type="PubMed" id="2998005"/>
            <dbReference type="DOI" id="10.1016/0042-6822(85)90115-1"/>
        </citation>
        <scope>NUCLEOTIDE SEQUENCE [GENOMIC DNA]</scope>
        <scope>PARTIAL PROTEIN SEQUENCE</scope>
    </reference>
    <reference key="2">
        <citation type="journal article" date="1995" name="Virology" volume="206" first="479" last="484">
            <title>Dual translational start motif evolutionarily conserved in the holin gene of Bacillus subtilis phage phi 29.</title>
            <authorList>
                <person name="Tedin K."/>
                <person name="Resch A."/>
                <person name="Steiner M."/>
                <person name="Blaesi U."/>
            </authorList>
            <dbReference type="PubMed" id="7831803"/>
            <dbReference type="DOI" id="10.1016/S0042-6822(95)80063-8"/>
        </citation>
        <scope>FUNCTION</scope>
        <scope>ALTERNATIVE INITIATION</scope>
    </reference>
    <reference key="3">
        <citation type="submission" date="1995-12" db="EMBL/GenBank/DDBJ databases">
            <authorList>
                <person name="Schicklmaier P."/>
                <person name="Huber J."/>
                <person name="Schmieger H."/>
            </authorList>
        </citation>
        <scope>NUCLEOTIDE SEQUENCE [GENOMIC DNA]</scope>
    </reference>
    <reference key="4">
        <citation type="journal article" date="2000" name="J. Bacteriol." volume="182" first="6472" last="6481">
            <title>Sequence of the genome of Salmonella bacteriophage P22.</title>
            <authorList>
                <person name="Vander Byl C.S."/>
                <person name="Kropinski A.M.B."/>
            </authorList>
            <dbReference type="PubMed" id="11053393"/>
            <dbReference type="DOI" id="10.1128/JB.182.22.6472-6481.2000"/>
        </citation>
        <scope>NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]</scope>
    </reference>
    <reference key="5">
        <citation type="journal article" date="2003" name="J. Bacteriol." volume="185" first="1475" last="1477">
            <title>Corrected sequence of the bacteriophage P22 genome.</title>
            <authorList>
                <person name="Pedulla M.L."/>
                <person name="Ford M.E."/>
                <person name="Karthikeyan T."/>
                <person name="Houtz J.M."/>
                <person name="Hendrix R.W."/>
                <person name="Hatfull G.F."/>
                <person name="Poteete A.R."/>
                <person name="Gilcrease E.B."/>
                <person name="Winn-Stapley D.A."/>
                <person name="Casjens S.R."/>
            </authorList>
            <dbReference type="PubMed" id="12562822"/>
            <dbReference type="DOI" id="10.1128/JB.185.4.1475-1477.2003"/>
        </citation>
        <scope>NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]</scope>
    </reference>
    <comment type="function">
        <text evidence="1">Accumulates harmlessly in the cytoplasmic membrane until it reaches a critical concentration that triggers the formation of micron-scale pores (holes) causing host cell membrane disruption and endolysin escape into the periplasmic space. Determines the precise timing of host cell lysis. Participates with the endolysin and spanin proteins in the sequential events which lead to the programmed host cell lysis releasing the mature viral particles from the host cell.</text>
    </comment>
    <comment type="subunit">
        <text evidence="1">Homomultimer. Interacts with isoform Antiholin; this interaction blocks the holin homomultimerization and delays host cell lysis.</text>
    </comment>
    <comment type="alternative products">
        <event type="alternative initiation"/>
        <isoform>
            <id>P09962-1</id>
            <name evidence="2">Antiholin</name>
            <name evidence="2">Lysis inhibitor 13-108</name>
            <sequence type="displayed"/>
        </isoform>
        <isoform>
            <id>P09962-2</id>
            <name evidence="2">Holin</name>
            <name evidence="2">Lysis protein 13-105</name>
            <sequence type="described" ref="VSP_058251"/>
        </isoform>
    </comment>
    <comment type="domain">
        <text evidence="1">Has 3 transmembrane regions whereas isoform Antiholin lacks the first transmembrane region.</text>
    </comment>
    <dbReference type="Proteomes" id="UP000001795">
        <property type="component" value="Genome"/>
    </dbReference>
    <dbReference type="Proteomes" id="UP000007960">
        <property type="component" value="Genome"/>
    </dbReference>
    <proteinExistence type="inferred from homology"/>
    <feature type="topological domain" description="Periplasmic" evidence="1">
        <location>
            <begin position="1"/>
            <end position="6"/>
        </location>
    </feature>
    <feature type="transmembrane region" description="Helical" evidence="1">
        <location>
            <begin position="7"/>
            <end position="26"/>
        </location>
    </feature>
    <feature type="topological domain" description="Cytoplasmic" evidence="1">
        <location>
            <begin position="27"/>
            <end position="35"/>
        </location>
    </feature>
    <feature type="modified residue" description="N-formylmethionine" evidence="1">
        <location>
            <position position="1"/>
        </location>
    </feature>
    <evidence type="ECO:0000250" key="1">
        <source>
            <dbReference type="UniProtKB" id="P03705"/>
        </source>
    </evidence>
    <evidence type="ECO:0000303" key="2">
        <source>
            <dbReference type="PubMed" id="7831803"/>
        </source>
    </evidence>
    <sequence length="105" mass="11294" checksum="14B153A499059FBD" modified="1989-07-01" version="1">MPEKHDLLTAMMAAKEQGIGAILAFAMAYLRGRYNGGAFKKTLIDATMCAIIAWFIRDLLVFAGLSSNLAYIASVFIGYIGTDSIGSLIKRFAAKKAGVDDANQQ</sequence>
</entry>
<copyright>
Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms Distributed under the Creative Commons Attribution (CC BY 4.0) License
</copyright>
</uniprot>