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Updated: Aug 7, 2026

High-throughput Screening of Carbohydrate-degrading Enzymes Using Novel Insoluble Chromogenic Substrate Assay Kits
Published on: September 20, 2016
[An enzyme from the fungus Aspergillus niger that hydrolyzes choline ethers]
Abstract:
The acetylthiocholine-hydrolyzing enzymatic activity inhibited by the neostigmine and partly physostigmine has been found in extracts from mycelium of fungus Aspergillus niger. The enzyme has been isolated and 15-20 fold purified. The cholinesterase activity of the protein (Kmu 7.10-7 M) is comparable with known for analogous enzymes from higher plants, for its inhibition high concentrations of substrate (greater than 10-3M) are required. The enzyme hydrolyzes acetylthiocholine with rate approximately 1.5 times higher than butyrylthiocholine. Molecular mass of native protein is approximately 600 kDa, subunits -63 and 44 kDa.
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