title: Enhanced stability of Bacillus licheniformis L-arabinose isomerase by immobilization with alginate.
abstract: Recombinant Escherichia coli whole cells harboring Bacillus licheniformis L-arabinose isomerase (BLAI) were harvested to prepare alginate-immobilized biocatalysts. The operational conditions for immobilization were optimized according to relative activity and the cell leakage of the immobilized cell. The optimal conditions are as follows: alginate concentration, Ca(2+) concentration, cell mass loading, and curing time were 2% (w/v), 0.1 M, 50 g l(-1), and 4 hours, respectively. After immobilization, cross-linking with 0.1% glutaraldehyde significantly reduced cell leakage. The immobilized whole cells harboring BLAI were very stable with 89% residual activity remaining after 33 days of incubation at 50 degrees C and were much more stable than the free enzyme and cells. The results showed that immobilizing whole cells harboring BLAI is suitable for use as a biocatalyst in the production of L-ribulose, largely due to its high stability and low cost.
authors.affiliation: Department of Chemical Engineering, Konkuk University, Gwangjin-Gu, Seoul, Korea.
authors.forename: Ye-Wang
authors.initials: YW
authors.lastname: Zhang
authors.forename: Ponnandy
authors.initials: P
authors.lastname: Prabhu
authors.forename: Jung-Kul
authors.initials: JK
authors.lastname: Lee
authors.forename: In-Won
authors.initials: IW
authors.lastname: Kim
mesh_terms: D019747:Aldose-Ketose Isomerases / Q000737:chemistry / Q000378:metabolism*; D000464:Alginates / Q000737:chemistry*; D001407:Bacillus / Q000201:enzymology*; D002118:Calcium / Q000737:chemistry; D018914:Cells, Immobilized / Q000201:enzymology; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D020723:Glucuronic Acid / Q000737:chemistry; D005976:Glutaral / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D010429:Pentoses / Q000096:biosynthesis; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism
chemical_list: D000464:Alginates; D004800:Enzymes, Immobilized; D006603:Hexuronic Acids; D010429:Pentoses; D011994:Recombinant Proteins; C100182:ribulose; D020723:Glucuronic Acid; D019747:Aldose-Ketose Isomerases; C019715:L-arabinose isomerase; D002118:Calcium; D005976:Glutaral