Proteins toxicity

Toxic Proteins, Peptides, Amides, and Amino Acids... 

Abrin A and Abrin B [1393-62-0] m, 63,000-67,000. Toxic proteins from seeds of... 

Prymnesin (toxic protein from phytoflagellate Pyrymnesium parvum) [11025-94-8]. Purified by column chromatography, differential soln and pptn in solvent mixtures and differential partition between diphasic mixtures. The product has at least 6 components as observed by TLC. [Ulitzur and Shilo Biochim Biophys Acta 301 350 1970.]... 

The previous ELP fusions all are examples of protein purification in which the ELP is covalently connected to the protein of choice. This approach is suitable for the purification of recombinant proteins that are expressed to high levels, but at very low concentrations of ELP the recovery becomes limited. Therefore this approach is not applicable for proteins expressed at micrograms per liter of bacterial culture, such as toxic proteins and complex multidomain proteins. An adjusted variant of ITC was designed to solve this problem. This variant makes use of coaggregation of free ELPs with ELP fusion proteins. In this coaggregation process, an excess of free ELP is added to a cell lysate to induce the phase transition at low concentrations of... 

Coelenterates and Echinoderms. Coelenterate and echinoderm toxins range from small molecular weight amines, to sterols, to large complex carbohydrate chains, to proteins of over 100,000 daltons. Molecular size sometimes reflects taxonomy, e.g., sea anemones (Actiniaria) all possess toxic polypeptides varying in size from 3,000 to 10,000 daltons while jellyfish contain toxic proteins (ca. 100,000 daltons). Carotenoids have been isolated from Asterias species (starfish), Echinoidea (sea urchins), and Anthozoans such as Actiniaria (sea anemones) and the corals. These are sometimes complexed with sterols (J5). 

Sea urchin toxins extracted from spines or pedicellariae have a variety of pharmacological actions, including electrophysiological ones (75). Dialyzable toxins from Diadema caused a dose-dependent increase in the miniature end-plate potential frequency of frog sartorius muscle without influencing membrane potential (76). A toxin from the sea urchin Toxopneustes pUeolus causes a dose-dependent release of histamine (67). Toxic proteins from the same species also cause smooth muscle contracture in guinea pig ileum and uterus, and are cardiotoxic (77). 

Agelasine, 320 Aiptasia pallida, 304,310 Aiptasia species, toxic protein, 321 Aiptasiolysin, 304,310 Alexandrium dinoflagellates clones, 36,38-3 saxitoxin source, 21 toxicity, 36... 

In the absence of an AGAC the ribosomes will prodnce the artificial polypeptides, polyphenylalanine (as specified by the codon UUU) or polyproline (as specified by the codon CCC). However, when streptomycin is added, the ribosomes prodnce a mixture of polythreonine (codon ACU) and poly serine (codon UCU). The misreading of the codons does not appear to be random U is read as A or C and C is read as A or U. If such misreading occurs in whole cells the accumulation of non-functional or toxic proteins would eventually prove fatal to the cells. There is some evidence that the bacterial cell membrane is damaged when the cells attempt to excrete the faulty proteins. 

K Sandvig, S Olsnes. (1982). Entry of toxic proteins abrin, modeccin, ricin, and diphtheria toxin into cells. I. Requirement for Ca2+. J Biol Chem 257 7495-7503. 

H-gal-GP and Hll do not simply have a digestive function but protect the parasite from ingested toxic proteins. 

Patocka Jiri, and Ladislav Streda. "Plant Toxic Proteins and Their Current Significance for Warfare and Medicine." Journal of Applied Biomedicine 1 (2003) 141-47. 

BoNTs form complexes with non-toxic proteins called progenitor toxin . Such proteins protect neurotoxins against the negative influences of the stomach environment and proteolytic enzymes. They also play an important... 

Cytotoxins Cytokine, interleukin, growth factor or the receptor binding domains of these proteins Toxin, toxic protein or apoptosis-inducing protein IL-2-DAB TGFa-PE40 IL-2-BAX bFGF-SAP bFGF-RNase [123] [124,125] [126] [127] [128]... 

C41 and C43 BL21 BL21 mutants that over-produce membranes enables expression of membrane-associated and toxic proteins... 

DETAILS Ricin is a toxic protein extracted from the castor bean seed. This bush is a common sight in the southwest United States where it can be found growing wild or cultivated as an ornamental shrub. The seeds are contained in a small spiny green seed pod about 5/8 inch in diameter. This pod is split open to reveal three small hard seeds. 

J. P. Taylor, J. Hardy, K. Fischbeck (2002). Toxic proteins in neurodegenerative disease. Science 296 1991-1995. 

For evaluation of efficiency of medical sorbents, the issue of their deliganding properties, i.e. an ability to withdraw toxic protein bound compounds (ligands) is of great importance. If a sorbent possesses strong deliganding capability as, for example, some types of modem carbon hemosorbents do [11,12], then after contact with such an adsorbent, the ratio of molar concentrations of ligand - protein carrier (M /Mp) decreases, i.e. the transport protein transforms into a more purified state than it was initially (Table 21.3). 

Inside the cell, aminoglycosides bind to specific 30S-subunit ribosomal proteins (S12 in the case of streptomycin). Protein synthesis is inhibited by aminoglycosides in at least three ways (Figure 45-3) (1) interference with the initiation complex of peptide formation (2) misreading of mRNA, which causes incorporation of incorrect amino acids into the peptide and results in a nonfunctional or toxic protein and (3) breakup of polysomes into nonfunctional monosomes. These activities occur more or less simultaneously, and the overall effect is irreversible and lethal for the cell. 

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