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Characterization of an Alkaline Alginate Lyase with pH-Stable and Thermo-Tolerance Property.

ABSTRACT: Alginate oligosaccharides (AOS) show versatile bioactivities. Although various alginate lyases have been characterized, enzymes with special characteristics are still rare. In this study, a polysaccharide lyase family 7 (PL7) alginate lyase-encoding gene, aly08, was cloned from the marine bacterium Vibrio sp. SY01 and expressed in Escherichia coli. The purified alginate lyase Aly08, with a molecular weight of 35 kDa, showed a specific activity of 841 U/mg at its optimal pH (pH 8.35) and temperature (45 °C). Aly08 showed good pH-stability, as it remained more than 80% of its initial activity in a wide pH range (4.0-10.0). Aly08 was also a thermo-tolerant enzyme that recovered 70.8% of its initial activity following heat shock treatment for 5 min. This study also demonstrated that Aly08 is a polyG-preferred enzyme. Furthermore, Aly08 degraded alginates into disaccharides and trisaccharides in an endo-manner. Its thermo-tolerance and pH-stable properties make Aly08 a good candidate for further applications.

SUBMITTER: Wang Y

PROVIDER: S-EPMC6562718 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature

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Characterization of an Alkaline Alginate Lyase with pH-Stable and Thermo-Tolerance Property.

Wang Yanan Y Chen Xuehong X Bi Xiaolin X Ren Yining Y Han Qi Q Zhou Yu Y Han Yantao Y Yao Ruyong R Li Shangyong S

Marine drugs 20190524 5

Alginate oligosaccharides (AOS) show versatile bioactivities. Although various alginate lyases have been characterized, enzymes with special characteristics are still rare. In this study, a polysaccharide lyase family 7 (PL7) alginate lyase-encoding gene, aly08, was cloned from the marine bacterium Vibrio sp. SY01 and expressed in Escherichia coli. The purified alginate lyase Aly08, with a molecular weight of 35 kDa, showed a specific activity of 841 U/mg at its optimal pH ( ...[more]

PMID: 31137685

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Dataset Information

Characterization of an Alkaline Alginate Lyase with pH-Stable and Thermo-Tolerance Property.

Publications

Characterization of an Alkaline Alginate Lyase with pH-Stable and Thermo-Tolerance Property.

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