Dithiobisnitrobenzoic acid

An enzymatic assay can also be used for detecting anatoxin-a(s). " This toxin inhibits acetylcholinesterase, which can be measured by a colorimetric reaction, i.e. reaction of the acetyl group, liberated enzymatically from acetylcholine, with dithiobisnitrobenzoic acid. The assay is performed in microtitre plates, and the presence of toxin detected by a reduction in absorbance at 410 nm when read in a plate reader in kinetic mode over a 5 minute period. The assay is not specific for anatoxin-a(s) since it responds to other acetylcholinesterase inhibitors, e.g. organophosphoriis pesticides, and would need to be followed by confirmatory tests for the cyanobacterial toxin. 

Selected entries from Methods in Enzymology [vol, page(s)] Assay with 2,2-dithiobisnitrobenzoic acid method, 233, 381-382 pH effects, 233, 384-385 formed by incubation with dithiothrei-tol, labeling, 233, 409-410 protein thiol assay, 234, 273-274 labeling, 233, 414 reactivity with free radicals and reactive oxygen species, 233, 405 reaction with ferrylmyoglobin, 233, 196-197. 

DEPC diethyl pyrocarbonate DIFP diisopropyl fluorophosphate DTNB 5,5 -dithiobisnitrobenzoic acid pCMB p-chloromercuribenzoate PMSF phenyl-methylsulfonyl fluoride TLCK N-tosyl-L-lysine chloromethylketone. 

Organophosphorus compounds—inhibition of cholinesterase. To each of two tubes add 3 ml of dithiobisnitrobenzoic acid solution, 0.1 ml of 5% acetylthiocholine iodide solution, and 20 ml of normal serum to the first tube add 0.2 ml of water and to the second tube add 0.2 ml of the filtered sample and allow to stand for 2 minutes. Any significant difference in colour between the tubes is suggestive of the presence of an organophosphorus compound or other cholinesterase inhibitor. 

Dithiobisnitrobenzoic Acid Solution dissolve 10 mg of 5,5 -dithiobis-2-nitrobenzoic acid in 100 ml o(phosphate... 

Ditan, 897 Ditaven, 541 Dithiazanine iodide, xvii Dithiobisnitrobenzoic acid solution, 1169 Dithionite test, on stomach contents, 6 on urine, 5 Dithranol, 567 Dithranol acetate, 568 Dithranol triacetate, 568 Dithrocream, 567 Dithrolan, 567, 965 Dithylinum, 998 Ditrazini citras, 538 Ditrosol, 555 Diubram, 454 Diucardin, 667 Diucen-H, 663 Diuchlor H, 663 Diulo, 111 Diumide-K, 634 Diupres, 454, 958 Diural, 634 Diuresal, 634 Diuret, 454... 

Acetylthiocholine Iodide, Another automated procedure for cholinesterase inhibition studies has been used by Levine et al. (18) and by Voss (19). The method uses acetylthiocholine iodide as substrate and dithiobisnitrobenzoic acid (DTNB). Cholinesterase sphts the substrate, and the thiocholine released reduces the DTNB to the yellow anion of thionitrobenzoic acid, whose absorbance is measured at 420 fi,... 

Fig. 3. Summary of key experiments examining transbilayer lipid movement in liposomes. Reaction of dithio-bisnitrobenzoic acid (DTNBA) with R-SH gives R-S-SNBA. Each of the experiments was specifically designed to initially sample only the outer leaflet of the bilayer and then at subsequent periods detect the movement of lipid from the inner to the outer leaflet of the bilayer. lAA, isethionylacetimidate TNBS, trinitrobenzenesulfonate DG, diacylglycerol DTNBA, dithiobisnitrobenzoic acid (Ellman s reagent).

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