AB toxin (original) (raw)
The AB toxins are two-component protein complexes secreted by a number of pathogenic bacteria, though there is a pore-forming AB toxin found the eggs of a snail. They can be classified as Type III toxins because they interfere with internal cell function. They are named AB toxins due to their components: the "A" component is usually the "active" portion, and the "B" component is usually the "binding" portion. The "A" subunit possesses enzyme activity, and is transferred to the host cell following a conformational change in the membrane-bound transport "B" subunit. These proteins consist of two independent polypeptides, which correspond to the A/B subunit moieties. The enzyme component (A) enters the cell through endosomes produced by the oligomeric binding/translocation protein (B), and pr
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| dbo:abstract | The AB toxins are two-component protein complexes secreted by a number of pathogenic bacteria, though there is a pore-forming AB toxin found the eggs of a snail. They can be classified as Type III toxins because they interfere with internal cell function. They are named AB toxins due to their components: the "A" component is usually the "active" portion, and the "B" component is usually the "binding" portion. The "A" subunit possesses enzyme activity, and is transferred to the host cell following a conformational change in the membrane-bound transport "B" subunit. These proteins consist of two independent polypeptides, which correspond to the A/B subunit moieties. The enzyme component (A) enters the cell through endosomes produced by the oligomeric binding/translocation protein (B), and prevents actin polymerisation through ADP-ribosylation of monomeric G-actin. Examples of the "A" component of an AB toxin include C. perfringens iota toxin Ia, C. botulinum C2 toxin CI, and Clostridium difficile ADP-ribosyltransferase. Other homologous proteins have been found in Clostridium spiroforme. An example of the B component of an AB toxin is Bacillus anthracis protective antigen (PA) protein, B. anthracis secretes three toxin factors: the protective antigen (PA); the oedema factor (EF); and the lethal factor (LF). Each is a thermolabile protein of ~80kDa. PA forms the "B" part of the exotoxin and allows passage of the "A" moiety (consisting of EF or LF) into target cells. PA protein forms the central part of the complete anthrax toxin, and translocates the A moiety into host cells after assembling as a heptamer in the membrane. The Diphtheria toxin also is an AB toxin. It inhibits protein synthesis in the host cell through phosphorylation of the eukaryotic elongation factor 2, which is an essential component for protein synthesis. The exotoxin A of Pseudomonas aeruginosa is another example of an AB toxin that targets the eukaryotic elongation factor 2. The AB5 toxins are usually considered a type of AB toxin, characterized by B pentamers. Less commonly, the term "AB toxin" is used to emphasize the monomeric character of the B component. The two-phase mechanism of action of AB toxins is of particular interest in cancer therapy research. The general idea is to modify the B component of existing toxins to selectively bind to malignant cells. This approach combines results from cancer immunotherapy with the high toxicity of AB toxins, giving raise to a new class of chimeric protein drugs, called immunotoxins. (en) AB-toxin är toxin som består av två sammanbundna protein som samverkar. A-delen står för den toxiska effekten när den väl kommit in i cellen. B-delen är värdspecifik och är konstruerad på ett sätt som gör att den binder till en kolhydratstruktur på cellytan hos en viss cell och får den cellen att ta upp toxinet. Botulinumtoxin (världens giftigaste) och tetanustoxin (stelkramp) är två AB-toxin som har samma A-del men olika B-del. De har alltså samma effekt när de kommit in i cellen (de hindrar att neurotransmittorer frisätts) men drabbar olika celler i kroppen. Botulinumtoxin drabbar perifera nervändar och orsakar förlamning medan tetanustoxin drabbar inhibitoriska nervändar och orsakar kramper. (sv) |
| dbo:symbol | ADPrib_exo_Tox Binary_toxB |
| dbo:thumbnail | wiki-commons:Special:FilePath/PDB_1giq_EBI.jpg?width=300 |
| dbo:wikiPageID | 20681039 (xsd:integer) |
| dbo:wikiPageLength | 8052 (xsd:nonNegativeInteger) |
| dbo:wikiPageRevisionID | 1122602452 (xsd:integer) |
| dbo:wikiPageWikiLink | dbr:Cancer dbr:Endosome dbr:Moiety_(chemistry) dbr:Toxalbumin dbr:C._botulinum dbr:Antigen dbr:C._perfringens dbc:Protein_families dbr:Pseudomonas_aeruginosa dbr:Clostridium_difficile_(bacteria) dbr:Enzyme dbr:Conformational_change dbr:Malignant dbr:Bacteria dbr:Actin dbr:Cell_(biology) dbr:Pseudomonas_exotoxin dbr:Cell_membrane dbr:Diphtheria_toxin dbr:Protein dbr:Bacillus_anthracis dbr:EEF2 dbr:Pathogenicity dbr:AB5_toxin dbc:Bacterial_toxins dbr:Homology_(biology) dbr:Transport dbr:Cancer_immunotherapy dbr:Mechanism_of_action dbr:Snail dbr:Exotoxin dbr:Perivitellin-2 dbr:Immunotoxins dbr:Chimera_(protein) dbr:Membrane-bound |
| dbp:caption | crystal structure of the anthrax toxin protective antigen heptameric prepore (en) crystal structure of the enzymatic component of iota-toxin from clostridium perfringens with nadh (en) |
| dbp:interpro | IPR003540 (en) IPR003896 (en) |
| dbp:name | ADPrib_exo_Tox (en) Binary_toxB (en) |
| dbp:pfam | PF03495 (en) PF03496 (en) |
| dbp:pfamClan | CL0084 (en) |
| dbp:scop | 1 (xsd:integer) |
| dbp:symbol | ADPrib_exo_Tox (en) Binary_toxB (en) |
| dbp:tcdb | 1 (xsd:integer) |
| dbp:wikiPageUsesTemplate | dbt:Infobox_protein_family dbt:InterPro_content dbt:Reflist dbt:Toxins |
| dct:subject | dbc:Protein_families dbc:Bacterial_toxins |
| gold:hypernym | dbr:Complexes |
| rdf:type | owl:Thing dbo:Biomolecule wikidata:Q206229 wikidata:Q8054 yago:Abstraction100002137 yago:Family108078020 yago:Group100031264 yago:Organization108008335 yago:YagoLegalActor yago:YagoLegalActorGeo yago:YagoPermanentlyLocatedEntity dbo:Building dbo:Protein yago:SocialGroup107950920 yago:Unit108189659 yago:WikicatProteinFamilies |
| rdfs:comment | The AB toxins are two-component protein complexes secreted by a number of pathogenic bacteria, though there is a pore-forming AB toxin found the eggs of a snail. They can be classified as Type III toxins because they interfere with internal cell function. They are named AB toxins due to their components: the "A" component is usually the "active" portion, and the "B" component is usually the "binding" portion. The "A" subunit possesses enzyme activity, and is transferred to the host cell following a conformational change in the membrane-bound transport "B" subunit. These proteins consist of two independent polypeptides, which correspond to the A/B subunit moieties. The enzyme component (A) enters the cell through endosomes produced by the oligomeric binding/translocation protein (B), and pr (en) AB-toxin är toxin som består av två sammanbundna protein som samverkar. A-delen står för den toxiska effekten när den väl kommit in i cellen. B-delen är värdspecifik och är konstruerad på ett sätt som gör att den binder till en kolhydratstruktur på cellytan hos en viss cell och får den cellen att ta upp toxinet. (sv) |
| rdfs:label | AB toxin (en) AB-toxin (sv) |
| owl:sameAs | freebase:AB toxin yago-res:AB toxin wikidata:AB toxin dbpedia-sv:AB toxin https://global.dbpedia.org/id/4K8wU |
| prov:wasDerivedFrom | wikipedia-en:AB_toxin?oldid=1122602452&ns=0 |
| foaf:depiction | wiki-commons:Special:FilePath/PDB_1giq_EBI.jpg wiki-commons:Special:FilePath/PDB_1tzo_EBI.jpg |
| foaf:isPrimaryTopicOf | wikipedia-en:AB_toxin |
| is dbo:wikiPageDisambiguates of | dbr:AB |
| is dbo:wikiPageRedirects of | dbr:A-B_toxin dbr:A-B_toxins dbr:A/B_toxin dbr:AB-type_toxins dbr:AB_toxins |
| is dbo:wikiPageWikiLink of | dbr:Toxalbumin dbr:Anthrax_toxin dbr:Cytolethal_distending_toxin dbr:Clostridioides_difficile dbr:Cyclic_adenosine_monophosphate dbr:Diphtheria_toxin dbr:AB dbr:Exotoxin dbr:Immunotoxin dbr:Perivitellin-2 dbr:Perivitellins dbr:A-B_toxin dbr:A-B_toxins dbr:A/B_toxin dbr:AB-type_toxins dbr:AB_toxins |
| is foaf:primaryTopic of | wikipedia-en:AB_toxin |
