Properties of "usual" and "atypical" serum cholinesterases using o-nitrophenyl butyrate as substrate.
نویسندگان
چکیده
The effects of varying concentrations of sodium chloride and formaldehyde on the activity of “usual” and “atypical” serum cholinesterases using o-nitrophenyl butyrate as substrate have been examined. The atypical enzyme has been shown to be more sensitive to either inhibitor than the usual enzyme. These results indicate two new methods for differentiating the two variants using a noncholine ester as substrate. Differential inhibition of the two enzymes by sodium chloride has been shown to be temperature-dependent.
منابع مشابه
Comparison of atypical and usual human serum cholinesterase. Purification, number of active sites, substrate affinity, and turnover number.
Atypical and usual human serum cholinesterases were purified and studied with the fluorescent probe, N-methyl-(7-dimethylcarbamoxy)quinolinium iodide. Four active sites per tetramer were found in each enzyme. The turnover numbers of usual and atypical cholinesterases were the same: 15,000 mumol of benzoylcholine hydrolyzed/min/mumol of active site; 48,000 min-1 for o-nitrophenylbutyrate; and 0....
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Atypical and usual human serum cholinesterases were purified and studied with the fluorescent probe, N-methyl(7-dimethylcarbamoxy)quinolinium iodide. Four active sites per tetramer were found in each enzyme. The turnover numbers of usual and atypical cholinesterases were the same: 15,000 pmol of benzoylcholine hydrol~zedlminl~mol of active site; 48,000 min-’ for o-nitrophenylbutyrate; and 0.002...
متن کاملSerum cholinesterase variants: examination of several differential inhibitors, salts, and buffers used to measure enzyme activity.
Dibucaine, used as a differential inhibitor with acetyl-, propionyl-, and butyr. ylthiocholine as substrate, clearly identified the “usual” and “atypical” serum cholinesterases. Succinylcholine was also used successfully as a differential inhibitor with butyrylthiocholine as substrate. Sodium fluoride, used as a differential inhibitor, gave conflicting results, depending on whether Tris or phos...
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V,,,, and K,,, values with twenty-five “atypical” and thirty-seven “usual” cholinesterase human sera were determined for the cholinesterase substrates procaine, tetracaine, benzoylcholine, o-nitrophenylbutyrate, cu-naphthylacetate and aspirin. Aspirin was demonstrated to be a substrate for serum cholinesterase. For each of these substrates the ratio of V,,substrate to V,,,, benzoylcholine was f...
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ورودعنوان ژورنال:
- Clinical chemistry
دوره 15 6 شماره
صفحات -
تاریخ انتشار 1969