Summary: Toxin Fst, type I toxin-antitoxin system
This is the Wikipedia entry entitled "Par stability determinant". More...
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Par stability determinant Edit Wikipedia article
|Secondary structure of RNAII|
|RNA type||Gene; antitoxin|
|Fst Type I toxin-antitoxin system|
The par stability determinant is a 400 bp locus of the pAD1 plasmid which encodes a type I toxin-antitoxin system in Enterococcus faecalis. It was the first such plasmid addiction module to be found in gram-positive bacteria.
The par locus contains two genes: fst which encodes a 33-amino acid toxic protein and a gene for RNAII, the small RNA anti-toxin which inhibits fst translation. The two genes are found on opposite DNA strands and share a 5' region which is where they are thought to have an antisense interaction. Their RNA secondary structures have been predicted computationally, the complementary regions appear to be presented on exposed loops for interaction.
par maintains pAD1 by means of post-segregational killing (PSK). If a daughter cell does not inherit the par locus, the unstable RNAII will quickly degrade leaving the long-lived fst toxin to damage or kill the daughter cell.
See also 
- Weaver KE, Walz KD, Heine MS (November 1998). "Isolation of a derivative of Escherichia coli-Enterococcus faecalis shuttle vector pAM401 temperature sensitive for maintenance in E. faecalis and its use in evaluating the mechanism of pAD1 par-dependent plasmid stabilization". Plasmid 40 (3): 225â32. doi:10.1006/plas.1998.1368. PMID 9806859.
- Weaver KE, Jensen KD, Colwell A, Sriram SI (April 1996). "Functional analysis of the Enterococcus faecalis plasmid pAD1-encoded stability determinant par". Mol. Microbiol. 20 (1): 53â63. doi:10.1111/j.1365-2958.1996.tb02488.x. PMID 8861204.
- Shokeen S, Greenfield TJ, Ehli EA, Rasmussen J, Perrault BE, Weaver KE (March 2009). "An intramolecular upstream helix ensures the stability of a toxin-encoding RNA in Enterococcus faecalis". J. Bacteriol. 191 (5): 1528â36. doi:10.1128/JB.01316-08. PMC 2648210. PMID 19103923. Retrieved 2010-09-20.
- Greenfield TJ, Ehli E, Kirshenmann T, Franch T, Gerdes K, Weaver KE (August 2000). "The antisense RNA of the par locus of pAD1 regulates the expression of a 33-amino-acid toxic peptide by an unusual mechanism". Mol. Microbiol. 37 (3): 652â60. doi:10.1046/j.1365-2958.2000.02035.x. PMID 10931358. Retrieved 2010-09-20.
- Gerdes K, Gultyaev AP, Franch T, Pedersen K, Mikkelsen ND (1997). "Antisense RNA-regulated programmed cell death". Annu. Rev. Genet. 31: 1â31. doi:10.1146/annurev.genet.31.1.1. PMID 9442888.
Further reading 
- Gerdes K, Gultyaev AP, Franch T, Pedersen K, Mikkelsen ND (1997). "Antisense RNA-regulated programmed cell death". Annu. Rev. Genet. 31: 1â31. doi:10.1146/annurev.genet.31.1.1. PMID 9442888. Retrieved 2010-08-09.
- Poulsen LK, Larsen NW, Molin S, Andersson P (November 1989). "A family of genes encoding a cell-killing function may be conserved in all gram-negative bacteria". Mol. Microbiol. 3 (11): 1463â72. doi:10.1111/j.1365-2958.1989.tb00131.x. PMID 2693900.
- Hayes F (September 2003). "Toxins-antitoxins: plasmid maintenance, programmed cell death, and cell cycle arrest". Science 301 (5639): 1496â9. doi:10.1126/science.1088157. PMID 12970556. Retrieved 2010-08-10.
- Gerdes K, Rasmussen PB, Molin S (May 1986). "Unique type of plasmid maintenance function: postsegregational killing of plasmid-free cells". Proc. Natl. Acad. Sci. U.S.A. 83 (10): 3116â20. doi:10.1073/pnas.83.10.3116. PMC 323463. PMID 3517851. Retrieved 2010-08-10.
This tab holds the annotation information that is stored in the Pfam database. As we move to using Wikipedia as our main source of annotation, the contents of this tab will be gradually replaced by the Wikipedia tab.
Toxin Fst, type I toxin-antitoxin system Provide feedback
Fst (faecalis plasmid stabilization toxin), also known as RNA I, is a toxic peptide. Its N-terminus forms a transmembrane alpha helix, its C terminus is disordered and is likely to be cytosolic. Its translation is inhibited by the antisense RNA, RNA II, which acts as an antitoxin [1,2].
Greenfield TJ, Weaver KE;, Mol Microbiol. 2000;37:661-670.: Antisense RNA regulation of the pAD1 par post-segregational killing system requires interaction at the 5' and 3' ends of the RNAs. PUBMED:10931359 EPMC:10931359
Gobl C, Kosol S, Stockner T, Ruckert HM, Zangger K;, Biochemistry. 2010;49:6567-6575.: Solution structure and membrane binding of the toxin fst of the par addiction module. PUBMED:20677831 EPMC:20677831
External database links
This tab holds annotation information from the InterPro database.
InterPro entry IPR025882
Fst (faecalis plasmid stabilisation toxin), also known as RNA I, is a toxic peptide. Its N terminus forms a transmembrane alpha helix, its C terminus is disordered and is likely to be cytosolic. Its translation is inhibited by the antisense RNA, RNA II, which acts as an antitoxin [PUBMED:10931359, PUBMED:20677831].
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|Number in seed:||13|
|Number in full:||45|
|Average length of the domain:||21.00 aa|
|Average identity of full alignment:||62 %|
|Average coverage of the sequence by the domain:||62.92 %|
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build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 23193494 -E 1000 --cpu 4 HMM pfamseq
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