High-Level Expression of a Thermally Stable Alginate Lyase Using Pichia pastoris, Characterization and Application in Producing Brown Alginate Oligosaccharide.

ABSTRACT: An alginate lyase encoding gene sagl from Flavobacterium sp. H63 was codon optimized and recombinantly expressed at high level in P.pastoris through high cell-density fermentation. The highest yield of recombinant enzyme of sagl (rSAGL) in yeast culture supernatant reached 226.4 μg/mL (915.5 U/mL). This was the highest yield record of recombinant expression of alginate lyase so far. The rSAGL was confirmed as a partially glycosylated protein through EndoH digestion. The optimal reaction temperature and pH of this enzyme were 45 °C and 7.5; 80 mM K⁺ ions could improve the catalytic activity of the enzyme by 244% at most. rSAGL was a thermal stable enzyme with T5015 of 57⁻58 °C and T5030 of 53⁻54 °C. Its thermal stability was better than any known alginate lyase. In 100 mM phosphate buffer o

SUBMITTER: Li H 

PROVIDER: S-EPMC5983289 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature