title: Comparative analysis of GFP(UV)-beta1,3-N-acetylglucosaminyltransferase 2 production in two insect-cell-based expression systems.
abstract: Active beta1,3-N-acetylglucosaminyltransferase 2 (beta3GnT2) was produced in the baculovirus expression system (BES) and in stably transformed insect Tn-5B1-4 cells. beta3GnT2 was expressed as a secreted fusion protein with GFP(UV) with three different types of signal sequence to enhance the secretion of the fusion protein. In the stably transformed cells, the maximal beta3GnT2 activity differed between isolates, but their secretion efficiencies were similar. The difference between the maximal beta3GnT activities of the isolates studied was considered to be due to the presence of a copy number of the fusion gene, as determined on the basis of the results of Southern blot analysis. The beta3GnT activities of the culture supernatant in BES (Tn-5B1-4 cells) without or with the addition of the protease inhibitor, leupeptin, were 0.68 and 2.01 mU/ml, respectively. The stably transformed Tn-5B1-4 cells (Tn-pXme11) exhibited a beta3GnT activity of 6.83 mU/ml, which was 3.4-fold higher than that observed for BES with the leupeptin addition. The purity of fusion protein purified from the culture supernatant of the Tn-pXme11 was higher than 95% on SDS-PAGE, in contrast with that purified from the culture supernatant of the baculovirus-infected cells which contained low-molecular-weight fragments of the fusion protein. The stably transformed cell line is more suitable than BES for the efficient production of the secretory protein, beta3GnT2.
authors.affiliation: Laboratory of Biotechnology, Department of Applied Biological Chemistry, Faculty of Agriculture, Shizuoka University, 836 Ohya, Shizuoka 422-8529, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Kato
authors.forename: Takeomi
authors.initials: T
authors.lastname: Murata
authors.forename: Taichi
authors.initials: T
authors.lastname: Usui
authors.forename: Enoch Y
authors.initials: EY
authors.lastname: Park
mesh_terms: D000818:Animals; D002460:Cell Line; D049452:Green Fluorescent Proteins; D006801:Humans; D007313:Insecta; D008164:Luminescent Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008555:Melitten / Q000235:genetics; D017351:N-Acetylglucosaminyltransferases / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D021382:Protein Sorting Signals; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D014170:Transformation, Genetic
chemical_list: D008164:Luminescent Proteins; D021382:Protein Sorting Signals; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins; D008555:Melitten; D017351:N-Acetylglucosaminyltransferases; C428132:B3GNT2 protein, human