Identification of a novel β-1,4-galactosyltransferase from <i>Haemophilus parainfluenzae</i> for efficient biosynthesis of lacto-<i>N</i>-neotetraose in <i>Escherichia coli</i>.

ABSTRACT: As an important member of human milk oligosaccharides (HMOs), lacto-N-neotetraose (LNnT) has been recognized as a promising HMO with many physiological activities for infants. β-1,4-Galactosyltransferases play a vital role in the final step of LNnT biosynthesis in microbial cell factory. Herein, we identified a novel β-1,4-galactosyltransferase (Hpa-GalT) from Haemophilus parainfluenzae for the efficient biosynthesis of LNnT in E. coli BL21 star(DE3). After overexpression of the key genes in the synthetic pathway, the titer of LNnT reached 1.86 g/L in shake flask fermentation. Moreover, a variant A186P/E146Q of Hpa-GalT was obtained by molecular modification, resulting in an increase of the LNnT titer to 2.15 g/L. Subsequently, a series of genes related to competitive

SUBMITTER: Liu D 

PROVIDER: S-EPMC12492647 | biostudies-literature | 2026 Mar

REPOSITORIES: biostudies-literature