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品牌：List Labs 

貨號：179A

品名：List LabsPertussis Toxin from B. pertussis (in Glycerol)

中文名：百日咳毒素

規(guī)格：50 ug

純度：>95%

形式：liquid

內(nèi)毒素水平：2 EU/mg

儲存溫度：-20°C

描述：

Pertussis toxin (PTX) is produced by Bordetella pertussis, the bacterium responsible for whooping cough. Pertussis toxin is a multi-component protein composed of six non-covalently bound subunits ranging in molecular weight from approximately 9 to 28 kDa. These subunits are designated as S1, S2, S3, S4 and S5 and occur in native pertussis toxin in a ratio of 1:1:1:2:1, where the subunit S4 is present in two copies.The largest subunit S1, also called the A protomer, is responsible for the ADP-ribosyltransferase activity; the A protomer alone will transfer the ADP ribose from NAD+ to α subunits of G proteins of the class Gαi, Gαo or Gαt. The crystal structure of PTX reveals a pyramid-like shape with the A protomer situated on top of the S5 subunit which rests on two dimers, S2-S4 and S3-S4.Together the five subunit platform is called the B oligomer and under certain conditions PTX dissociates into just two parts, the enzymatic A protomer and the five subunit binding complex, the B oligomer. This B oligomer allows PTX to enter most cells, attaching to glycan residues present on receptor proteins including TLR4 and glycoprotein Ib. After entering the cell via receptor-mediated endocytosis, PTX is transported retrogradely via the endosomal pathway and Golgi complex to the endoplasmic reticulum. A protomer is released from the toxin and translocates through the membrane of the endoplasmic reticulum where the toxin inactivates the target membrane-bound G proteins.

注：產(chǎn)品僅用于研究目的，不得用于人體或作為診斷劑。