الفهرس 
Cloning, expression and characterization of bacterial L-arabinose isomerase
AbstractOnly 14 pages are availabe for public view
 |  | from | 149 |  |  |
| | | from | 149 | | |
Abstract
L-Arabinose isomerase genes from Bacillus amyloliquefaciens CAAI and Enterococcus faecium SCAI were cloned and over-expressed in Escherichia coli as soluble and functional proteins. The recombinant enzymes were purified to apparent homogeneity by Ni-NTA affinity chromatography and partially characterized. Besides, biosynthesis of D-tagatose was achieved by constructing and expressing a polycistronic plasmid encoding codon-optimized thermostable Ý-galactosidase from Marinomonas sp. BSi20414 and L-arabinose isomerase from Clostridium hylemonae, simultaneously, in Lactococcus lactis NZ3900. Results revealed an efficient bioconversion of lactose to D-tagatose and maximum production was accomplished at 60{u00B0}C after 12 h, starting with 20% (w/v) lactose. The induced recombinant cells entrapped in chitosan beads converted up to 34% of lactose into D-tagatose in a single step that could be implemented in safe-production of food-grade low-calorie sweetener