Distinct kinetics of (H/K/N)Ras glucosylation and Rac1 glucosylation catalysed by Clostridium sordellii lethal toxin

Abstract

MINT‐7261784: TcsL (uniprotkb:Q46342) enzymaticly reacts (MI:0414) N‐RAS (uniprotkb:P01111) by enzymatic studies (MI:0415)

Molecular Characteristics of Clostridium perfringens TpeL Toxin and Consequences of Mono-O-GlcNAcylation of Ras in Living Cells

“…Moreover, spectrometric analysis definitely show that Ras is modified by attachment of GlcNAc in intact cells. Interestingly, also C. sordellii lethal toxin, which modifies Ras and Rac by glucosylation, prefers Ras in vitro (35,36) and in intact cells (36,37). Importantly, our studies on the apoptosis of HeLa cells were performed at rather high concentrations of TpeL (10 nM), where Ras as well as Rac1 is probably modified by the toxin.…”

Large clostridial glycosylating toxins modifying small GTPases

“…Decreased detection is in fact due to glucosylation (and not due to degradation), so long as the cellular level of Rac/Cdc42 and Ras is unchanged upon the application of alternative antibodies that detect Rac/Cdc42 and Ras, regardless of glucosylation. Nowadays, the nonradioactive, cost-effective immunoblot detection is widely applied instead of the previously applied sequential LCGT-catalyzed [ 14 C]glucosylation of Rho-/Ras-GTPases and sequential exoenzyme C3-catalyzed [ 32 P]ADP-ribosylation of RhoA/B/C [136,142,143].…”

Difference in F-Actin Depolymerization Induced by Toxin B from the Clostridium difficile Strain VPI 10463 and Toxin B from the Variant Clostridium difficile Serotype F Strain 1470

“…Lethal toxin from C. sordellii (TcsL) is closely related to TcdBF, as it glucosylates Rac1 and Ras proteins but not Rho(A/B/C) [27,28,29]. TcsL induced rounding of HeLa cells (Figure 1) and of NIH3T3 fibroblasts (Figure 4), with F-actin being present at the plasma membrane and in the cytosol.…”

“…It can be quantified either in terms of rounded per total cells [5] or in terms of the decreased cell diameter in any cultured cell lines with a spread phenotype including epithelial cells, fibroblasts, and adherently growing myeloid cells [32]. The cytopathic effect is a particularly useful measure, as its kinetics reflect the glucosylation of Rho proteins by clostridial toxins [5,29,33]. The quantification of the cytopathic effect by cell rounding moreover represents an established application using a simple and straightforward method with reliable results.…”