Patent ID: 6287866
Filing Date: 2001-09-11
Classification: A61K,C07K,C12N,C12P

Abstract:
A method of improving the genetic stability of a plasmid-containing cell during fermentation comprising the steps of: 1) transforming a cell with a vector comprising an isolated DNA sequence comprising a nucleotide sequence encoding human .beta.-casein, wherein said nucleotide sequence is operably linked to a promoter, a nucleotide sequence encoding a first subunit of a kinase, a nucleotide sequence encoding a second subunit of said kinase, a nucleotide sequence encoding a peptidase and a nucleotide sequence encoding a bacterial resistance marker, 2) prior to fermentation, growing said cell in a culture utilized for inoculating a fermentor, 3) growing said cell in said fermentor, 4) inducing at least one of said nucleotide sequences present in said vector, and 5) completing fermentation for a time and under conditions suitable for optimal expression of said at least one nucleotide sequence, said method resulting in a cell having improved genetic stability during fermentation.