The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 08, 1992
Filed:
Aug. 28, 1989
Keith C Backman, Bedford, MA (US);
BioTechnica International, Inc., Cambridge, MA (US);
H.J. Heinz Company, Pittsburgh, PA (US);
Abstract
A method of controlling of cell mass by starving cells that are ppc.sup.- and pc.sup.- for tricarboxylic acid cycle (TAC) intermediates, while fermenting a product compound. The cells are adapted to enable or enhance conversion of a raw material to the product via a bioconversion pathway that does not include any TAC intermediates, and preferably they are either conditionally or permanently incapable of producing a net increase in TAC intermediates via any anaplerotic pathways. First the cells are cultured to the desired cell mass under growth medium conditions characterized by the presence of at least one TAC intermediate, or by the presence of a compound that the cells can convert to a TAC intermediate via an anaplerotic pathway under the conditions present in the growth medium. In that way the medium provides the cell enough TAC intermediates to support growth. When the desired cell density has been reached, the cells are cultured under product-production medium conditions in which the cell does not receive adequate TAC intermediates to support growth, because the medium lacks TAC intermediates as well as compounds that they all can convert to TAC intermediate via an anapleortic pathway.