Enzymatic Synthesis of Galactosylated Serine/Threonine Derivatives by β-Galactosidase from Escherichia coli.

ABSTRACT: The transgalactosylations of serine/threonine derivatives were investigated using β-galactosidase from Escherichia coli as biocatalyst. Using ortho-nitrophenyl-β-D-galactoside as donor, the highest bioconversion yield of transgalactosylated N-carboxy benzyl L-serine benzyl ester (23.2%) was achieved in heptane:buffer medium (70:30), whereas with the lactose, the highest bioconversion yield (3.94%) was obtained in the buffer reaction system. The structures of most abundant galactosylated serine products were characterized by MS/MS. The molecular docking simulation revealed that the binding of serine/threonine derivatives to the enzyme's active site was stronger (-4.6~-7.9 kcal/mol) than that of the natural acceptor, glucose, and mainly occurred through interactions with aromatic residues. F

SUBMITTER: Seo S 

PROVIDER: S-EPMC4490519 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature