title: High cell density fermentation of recombinant Vibrio cholerae for the production of B subunit of Escherichia coli enterotoxin.
abstract: High cell density fermentation studies were performed to produce the B subunit of Escherichia coli heat-labile enterotoxin (LTB) from a Vibrio cholerae culture that carries a recombinant plasmid with an ampicillin resistance gene, tac promoter, and the gene encoding LTB. Upon induction with isopropyl-beta-D-thiogalactopyranoside (IPTG) the culture secreted the protein into the extracellular milieu. Fed-batch fermentation with stepwise addition of a total of 5 mM of IPTG during the active growth phase of the organism resulted in the production of 400 mg/L of LTB in 9 h and a cell optical density (OD) of 24. The LTB was purified to homogeneity with 70% recovery from the fermentation broth and was found to be chemically and biologically identical to the native protein by N-terminal amino acid sequencing and receptor binding assay. (c) 1995 John Wiley & Sons, Inc.
authors.affiliation: National institute of immunology, Aruna Asaf Ali Marg, New Delhi 110067, India.
authors.forename: A K
authors.initials: AK
authors.lastname: Panda
authors.forename: A
authors.initials: A
authors.lastname: Ghorpade
authors.forename: A
authors.initials: A
authors.lastname: Mukhopadhyay
authors.forename: G P
authors.initials: GP
authors.lastname: Talwar
authors.forename: L C
authors.initials: LC
authors.lastname: Garg