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

Naoki Shirasaka; Koichi Harazono; Ryota Nakahigashi; Keigo Mitsui; Jun Tanaka; Sayaka Tanazawa; Masaru Mitsutomi; Takayuki Ohnuma

doi:10.5458/jag.jag.JAG-2019_0001

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

J Appl Glycosci (1999). 2019 Aug 20;66(3):83-88. doi: 10.5458/jag.jag.JAG-2019_0001. eCollection 2019.

Authors

Naoki Shirasaka¹, Koichi Harazono¹, Ryota Nakahigashi¹, Keigo Mitsui², Jun Tanaka², Sayaka Tanazawa², Masaru Mitsutomi³, Takayuki Ohnuma²

Affiliations

¹ 1 Nagase ChemteX Corporation.
² 2 Department of Advanced Bioscience, Kindai University.
³ 3 Department of Applied Biochemistry and Food Science, Saga University.

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.

Keywords: N-acetylhexosaminidase; antifungal activity; biopreservation; chitin.

2019 by The Japanese Society of Applied Glycoscience.