Pertussis Toxin-ATP Complex: Difference between revisions
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==structure== | ==structure== | ||
The pertussis toxin has been characterized as being an AB toxin meaning that there are 2 subunits: A subunit possesses the enzyme activity and the B possesses it the receptor binding portion. PT in particular is an AB5 toxin consisting of a six-component protein complex. With that in mind, this protein is a hexamer containing a catalytic (S1) subunit that is tightly associated with the pentameric cell-binding component (B-oligomer). The S1 component is a single subunit <scene name='Pertussis_Toxin-ATP_Complex/Subunit_1/3'>S1 (chains A,G)</scene> while the B-oligomer is a pentamer composed of four types of subunits: <scene name='Pertussis_Toxin-ATP_Complex/Subunit_2/3'>S2 (chains B,H)</scene>, | The [http://en.wikipedia.org/wiki/Pertussis_toxin pertussis toxin] has been characterized as being an AB toxin meaning that there are 2 subunits: A subunit possesses the enzyme activity and the B possesses it the receptor binding portion. PT in particular is an AB5 toxin consisting of a six-component protein complex. With that in mind, this protein is a hexamer containing a catalytic (S1) subunit that is tightly associated with the pentameric cell-binding component (B-oligomer). The S1 component is a single subunit <scene name='Pertussis_Toxin-ATP_Complex/Subunit_1/3'>S1 (chains A,G)</scene> while the B-oligomer is a pentamer composed of four types of subunits: <scene name='Pertussis_Toxin-ATP_Complex/Subunit_2/3'>S2 (chains B,H)</scene>, | ||
<scene name='Pertussis_Toxin-ATP_Complex/Subunit_3/5'>S3 (chains C,I)</scene>, two copies of <scene name='Pertussis_Toxin-ATP_Complex/Subunit_4/3'>S4 (chains D,E,J,K)</scene>, and <scene name='Pertussis_Toxin-ATP_Complex/Subunit_5/4'>S5 (chains F,L)</scene>.<ref name=Hazes>PMID: 8637000</ref> These subunits are encoded by a ptx genes, which are encoded on a large PT operon that includes additional genes as well such as Pti genes. Together the PT and Pti proteins form the PT secretion complex. | <scene name='Pertussis_Toxin-ATP_Complex/Subunit_3/5'>S3 (chains C,I)</scene>, two copies of <scene name='Pertussis_Toxin-ATP_Complex/Subunit_4/3'>S4 (chains D,E,J,K)</scene>, and <scene name='Pertussis_Toxin-ATP_Complex/Subunit_5/4'>S5 (chains F,L)</scene>.<ref name=Hazes>PMID: 8637000</ref> These subunits are encoded by a ptx genes, which are encoded on a large PT operon that includes additional genes as well such as Pti genes. Together the PT and Pti proteins form the PT secretion complex. | ||