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Characterization of a GH Family 20 Exo-β-N-acetylhexosaminidase with Antifungal Activity from Streptomyces avermitilis.

ABSTRACT: We characterized SaHEX, which is a glycoside hydrolase (GH) family 20 exo-β-N-acetylhexosaminidase found in Streptomyces avermitilis. SaHEX exolytically hydrolyzed chitin oligosaccharides from their non-reducing ends, and yielded N-acetylglucosamine (GlcNAc) as the end product. According to the initial rate of substrate hydrolysis, the rates of (GlcNAc)₃ and (GlcNAc)₅ hydrolysis were greater than the rates for the other oligosaccharides. The enzyme exhibited antifungal activity against Aspergillus niger, which was probably due to hydrolytic activity with regard to chitin in the hyphal tips. Therefore, SaHEX has potential for use in GlcNAc production and food preservation.

SUBMITTER: Shirasaka N

PROVIDER: S-EPMC8137315 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Characterization of a GH Family 20 Exo-β-N-acetylhexosaminidase with Antifungal Activity from Streptomyces avermitilis.

Shirasaka Naoki N Harazono Koichi K Nakahigashi Ryota R Mitsui Keigo K Tanaka Jun J Tanazawa Sayaka S Mitsutomi Masaru M Ohnuma Takayuki T

Journal of applied glycoscience 20190820 3

We characterized SaHEX, which is a glycoside hydrolase (GH) family 20 exo-β-N-acetylhexosaminidase found in Streptomyces avermitilis. SaHEX exolytically hydrolyzed chitin oligosaccharides from their non-reducing ends, and yielded N-acetylglucosamine (GlcNAc) as the end product. According to the initial rate of substrate hydrolysis, the rates of (GlcNAc)3 and (GlcNAc)5 hydrolysis were greater than the rates for the other oligosaccharides. T ...[more]

PMID: 34354524

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