5n7j

Publication Abstract from PubMed

Amylosucrase from Neisseria polysaccharea naturally catalyzes the synthesis of alpha-1,4 glucans from sucrose. The product profile is quite polydisperse, ranging from soluble chains called maltooligosaccharides to high-molecular weight insoluble amylose. This enzyme was recently subjected to engineering of its active site to enable recognition of non-natural acceptor substrates. Libraries of variants were constructed and screened on sucrose, allowing the identification of a mutant that showed a 6-fold enhanced activity toward sucrose compared to the wild-type enzyme. Furthermore, its product profile was unprecedented, as only soluble maltooligosaccharides of controlled size chains (2<DP<21) with a narrow polydispersity were observed. This variant, containing 9 mutations in the active site, was characterized at both biochemical and structural levels. Its x-ray structure was determined and further investigated by molecular dynamics to understand the molecular origins of its higher activity on sucrose and higher production of small maltooligosaccharides, with a totally abolished insoluble glucan synthesis.

Engineering of anp efficient mutant of Neisseria polysaccharea amylosucrase for the synthesis of controlled size maltooligosaccharides.,Verges A, Barbe S, Cambon E, Moulis C, Tranier S, Remaud-Simeon M, Andre I Carbohydr Polym. 2017 Oct 1;173:403-411. doi: 10.1016/j.carbpol.2017.06.011. Epub, 2017 Jun 7. PMID:28732882^[2]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.