title: Synthesis and excretion of alpha-amylase in vgb+ and vgb- recombinant Escherichia coli: a comparative study.
abstract: Synthesis and excretion of alpha-amylase is investigated in batch cultures of Escherichia coli JM103[pMK57] (vgb-) and E. coli JM103[pMK79] (vgb+). While total production and excretion of alpha-amylase were promoted in Luria broth (LB) (excretion being as high as 87%), cell-mass-specific production of the enzyme was promoted in M9 in bioreactor cultures and in LB in shake flask cultures. Low aeration and agitation rates and presence of starch were conducive to alpha-amylase synthesis in E. coli JM103[pMK79]. Two-stage bioreactor operating strategies that will improve alpha-amylase production are proposed. The potential of these strategies is demonstrated via two-stage shake flask cultures.
authors: Department of Chemical and Environmental Engineering. Illinois Institute of Technology, Chicago, 60616, USA.
authors: C
authors: C
authors: Tari
authors: S J
authors: SJ
authors: Parulekar
authors: B C
authors: BC
authors: Stark
authors: D A
authors: DA
authors: Webster
mesh_terms: D019149:Bioreactors; D018929:Cell Culture Techniques / Q000379:methods; D003470:Culture Media / Q000378:metabolism; D004926:Escherichia coli / Q000378:metabolism*; D006454:Hemoglobins / Q000235:genetics*; D013997:Time Factors; D000516:alpha-Amylases / Q000378:metabolism*
chemical_list: D003470:Culture Media; D006454:Hemoglobins; D000516:alpha-Amylases