Of protein toxins

K Sandvig, S Olsnes. (1984). Receptor-mediated entry of protein toxins into cells. Acta Histochem 29 979-994. 

It is also important to have multiple biomarker masses to use in the search. In samples of protein toxins, and of many viruses (e.g., see Figure 12.2), only one of two proteins may be ionized and analyzed for database searching.15,74-76... 

Song X., Swanson B.I., Direct, ultrasensitive, and selective optical detection of protein toxins using multivalent interactions, Anal. Chem. 1999 71 2097-2107. 

The following sections of this review will now transition into a unique group of protein toxins, the SEs and TSST-1. These proteins secreted by S. aureus vcovk in a different fashion versus the aforementioned binary toxins. In fact, these staphylococcal toxins do not enter a cell and do not directly injure the targeted cell surface. Toxin damage is insidiously indirect and caused by an over zealous response executed by the host s immune system. 

S. Olsnes J. Wesche P. O. Falnes, Uptake of Protein Toxins Acting Inside Cells. In Bacterial Protein Toxins] K. Aktorles, I. Just, Eds. Springer Berlin, 2000 Vol. 145, Chapter 1, pp 1-19. 

Falnes, P.O. and Sandvig, K., Penetration of protein toxins into cells, Curr. Opin. Cell Biol., 12, 407 13, 2000. 

Targeted Delivery of Protein Toxins to Tumor Cells... 

Phillips KS, Han J-H, Martinez M, Wang Z, Carter D, Cheng Q (2006) Nanoscale classifcia-tion of gold substrates for surface plasmon resonance analysis of protein toxins with supported lipid membranes. Anal Chem 78 596-603... 

Fig. 3.3 shows the principle behind the design of immunotoxins. A number of protein toxins of bacterial and plant origin are useful for the production of immunotoxins. These include the diphtheria toxin and pseudomonas exotoxin from bacteria, and ricin, arbin, pokeweed antiviral proteins, saporin, and gelonin from plants (Pastan et al, 1986 Pastan and FitzGerald, 1991). All of these toxins kill cells by entering the cells, and enzymatically inactivating the translational machinery of the cells. Some, such as diphtheria toxin, arbin, and ricin, are composed of two protein chains, A and B. The B chains bind to the cell-surface... 

It should also be pointed out in this connection that clathrin-coated pits are not the only route of endocytosis into eukaryotic cells. There are also other coat proteins. Studies of protein toxins have shown that some (e.g. cholera toxin) enter the cell without the aid of clathrin. 

It is being recognized that an increasing number of protein toxins from bacteria and plants act on targets located in the cytosol. Recently it has been shown that such toxins can be used to carry passenger proteins across cellular membranes into the cytosol. A common feature of the toxins in question is that they consist of two functionally different parts, A and B. The B-moiety binds the toxin to cell surface receptors, a binding which is required to produce the toxic effect at low concentrations of the toxin. The A-moiety is an enzyme that enters the cytosol and damages intracellular components. The B-moiety may be a separate part of the same protein as the A-moiety, or it may consist of one or several separate polypeptides. 

Last not least, I would like to thank all the authors for their outstanding effort. I am convinced that their excellent contributions will inspire research in the field of protein toxins and facilitate the use of toxins as tools in biological sciences. 

Interestingly, knowledge gained from the study of protein toxins has proven highly useful in the design of receptor-targeted drugs. Thus, it was learned early... 

Applications of immunoassay to pesticide chemistry have been described which address some difficult problems in analysis by classical methods. These include stereospecific analysis of optically active compounds such as pyrethroids (38), analysis of protein toxins from Bacillus thuringiensis (5,37), and compounds difficult to analyze by existing methods, such as diflubenzuron (35) and maleic hydrazide (15 also Harrison, R.O. Brimfield, A.A. Hunter, K.W.,Jr. Nelson, J.O. J. Agric. Food Chem. submitted). An example of the excellent specificity possible is seen in assays for parathion (10) and its active form paraoxon (3). Some immunoassays can be used directly for analysis without extensive sample extraction or cleanup, dramatically reducing the work needed in typical residue analysis. An example of this is given in Figures 2 and 3, comparing the direct ELISA analysis of molinate in rice paddy water to the extraction required before GC analysis. 

Chen A, Hu T, Mikoryak C et al. (2002). Retrograde transport of protein toxins under conditions of COP1 dysfunction. BiochimBiophys Acta, 1589, 124-139. 

Hudson T, Neville D. Temporal separation of protein toxin translocation from processing events. J Biol Chem. 1987 262 16484-16494. 

In Chapter 10, Samnel Hemandez-Rivera and cowoikers show that Raman detection of trace amoimts of explosives and other hazardous materials on surfaces can be improved by ten to one thousand times with the addition of colloidal metallic nanoparticles to contaminated areas. Banahalli Ratna and colleagues demonstrate that orgarrized spatial distribution of fluorescent reporter molecules on a virus capsid eliminates the commonly encountered problem of fluorescence quenching. Using such viral nanoparticles, they show in Chapter 11 that enhanced fluorescence for the detection of protein toxins is possible. 

Zhou CE, Smith J, Lam M, etal. MvirDB—a microbial database of protein toxins, virulence factors and antibiotic resistance genes for bio-defence applications. Nucl Acids Res. 2007 35 D391-4. doi 10.1093/nar/gkl791. 

Karlsson, E., 1979, Chemistry of protein toxins in snake venoms. In hand book of experimental pharmacology ( Lee, C.Y, Eds.) Springer Verlag, Berlin. Vol 52 pp 159-172. 

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