首先采用原核表达并纯化出97 kDa 的受体结合域 (receptor binding domain, RBD) 蛋白,并利用杂交瘤技术成功筛选出能稳定分泌针对RBD蛋白的单克隆抗体杂交瘤细胞AE2D3,经检测其抗体亚型为IgG2b (κ)。其次以针对RBD蛋白的单克隆抗体为检...
We note that many of the potent neutralizers of TcdA bind epitopes within the delivery domain, a finding that could reflect roles of the delivery domain in receptor binding and/or the conserved role of pore-formation in the delivery of the toxin enzyme domains to the ...
Our recombinant TcdB consists of the enzymatic domain. Both TcdA and TcdB also have potassium-dependent UDP-Glc hydrolase activity, which is essentially glucosyltransferase activity with water as the acceptor molecule (7). Under same conditions, UDP-glucose hydrolysis by TcdB occurs at a rate about...
a)ThecysteineproteaseC-domaincanbecharacterizedbythecatalytictriadconsistingofAsp587,His653andCys698(DHC).b)TheDXG(D1665)motifwassuggestedtobepartofanaspartateproteasedomain,possiblyinvolvedinprocessingofthetoxins.3.theN-terminalenzymedomain ①TheNterminusharborstheglucosyltransferaseactivityofthetoxinsandisthe...
3. the N-terminal enzyme domain The N terminus harbors the glucosyltransferase activity of the toxins and is the biological activity domain The catalytic core is formed by a mixed a/b-fold with mostly parallel b-strands These additional residues are mainly helices, possibly involved in membrane ...
GTD: glucosyltransferase domain, CPD: cysteine protease domain, DRBD: delivery and receptor-binding domain, CROPs: combined repetitive oligopeptides domain, Hinge: a key fragment between the DRBD and CROPs that mediates structural communications among all four domains of TcdB. CSPG4 is composed of ...
(25, 26), and excess TcdA CROPS domain can compete with TcdA holotoxin for cell binding (27). At the same time, truncations of TcdA and TcdB that lack the CROPS domains are still capable of intoxicating cells (7, 28, 29) and a homologous toxin from ...
Using a series of C-terminal truncations, we show that the CSPG4-binding site on TcdB extends into the CROP domain, requiring three short repeats for binding and for full toxicity on CSPG4-expressing cells. Consistent with the location of the CSPG4-binding site on TcdB, we show that ...
Blister formation and chromatin condensation was specifically induced by the glucosyltransferase domain of TcdB from strain VPI10473 since neither TcdBF from cdi1470 nor the chimera of TcdB harbouring the glucosyltransferase domain of TcdBF was able to induce these effects. In summary, TcdB induces ...
Most surprisingly, Ax, independent of its effects on endosomal acidification, decreased the toxins' intracellular enzyme activity, which is mediated by a catalytic glucosyltransferase domain. Considering its undoubted safety profile, Ax might be taken into account as therapeutic o...