Shiga toxin subunits

Goud B, Salamero J, Johannes L. Targeting of Shiga toxin b- 28. subunit to retrograde transport route in association with detergent-resistant membranes. Mol. Biol. Cell 2001 12 2453-2468. 

Shiga toxin produced by Shigella dysenteriae has similar structural features. The toxin binds to a glycolipid (Gb3), undergoes endocytosis, and the enzymatie Ai fragment, which is a specific N-glycosidase, removes adenine from one particular adenosine residue in the 28S RNA of the 60S ribosomal subunit. Removal of the adenine inactivates the 60S ribosome, blocking protein synthesis. Ricin, abrin, and a number of related plant proteins inhibit eukaryotic protein synthesis in a similar manner (Chapter 25). 

Ryd, M., Verma, N. and Lindberg, A.A. (1992) Induction of a humoral immune response to a Shiga toxin B subunit epitope expressed as a chimeric LamB protein in a Shigella flexneri live vaccine strain. Microb Pathog, 12, 399 07. 

In a series of experiments designed to characterize the comparative mechanisms of Pseudomonas and Shiga toxin transfer from the Golgi complex to the ER, investigators first sequenced the respective targeting subunits. The C-terminal 24 amino acids of the B subunits of Pseudomonas toxin and Shiga toxin are shown below ... 

C-termlnal 24 amino acids of Shiga toxin B subunit TGMTVTIKTN ACHNGGGFSE VIFR... 

Effect of microinjected antibodies directed against COPI proteins on the transport of wild type Shiga toxin B-subunit or Shiga toxin B-KDEL from Golgi complex to the ER. 

Shiga toxin, a bacterial toxin produced by Shigella dysenteriae belonging to the AB5 toxins family. It is structurally related to verotoxin and cholera toxin. Shiga toxin is composed of two subunits. The monomeric A-subunit has a N-glycosidase activity causing inhibition of protein synthesis and cell death. The B-subunit is a homopentamer which is responsible for receptor binding, internalization and intracellular transport of the holotoxin [E. A. Meritt, W. G. Hoi, Curr. Opin. Struct. Biol. 1995, 5, 165 D. G. Pina et al., Biochim. Biophys. Acta 2007, 1768, 628]. 

Haicheur N, Bismuth E, Bosset S et al. The B subunit of Shiga toxin fused to a tumor antigen elicits CTL and targets dendritic cells to allow MHC class I-restricted presentation of peptides derived from exogenous antigens. J Immunol 2000 165(6) 3301-3308. 

Fagerquist, C.K., Sultan, O. (2011) Induction and identification of disulfide-intact and disulfide-reduced P-subunit of Shiga toxin 2 from Escherichia coli 0157 H7 using MALDI-TOF-TOF-MS/MS and top-down proteomics. Analyst, 136, 1739-1746 (published on-line February 21). 

Nanowire-based delivery of Escherichia coli 0157 shiga toxin 1 A subunit into human and bovine cells. 

CEGF-SLT comprises Cys-tagged EGF fused to catalytic subunit of E. coli Shiga-like toxin. 

St. Hilaire PM, Boyd MK, Toone EJ. Interaction of the Shiga-like toxin type 1 B-subunit with its carbohydrate receptor. Biochemistry 1994 33 14452-14463. 

Acheson, D.W., Levine, M.M., Kaper, J.B. and Keusch, G.T. (1996) Protective immunity to Shiga-like toxin I following oral immunization with Shiga-Uke toxin I B-subunit-producing Vibrio cholerae CVD 103-HgR. Infect Immun, 64, 355-357. 

Boyd, B., Richardson, S. and Gariepy, J. (1991) Serological responses to the B subunit of Shiga-like toxin 1 and its peptide fragments indicate that the B subunit is a vaccine candidate to counter action of the toxin. Infect Immun, 59, 750-757. 

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