ISSN:
0006-3592
Keywords:
pet operon
;
E. coli
;
metabolic fluxes
;
metabolic engineering
;
Chemistry
;
Biochemistry and Biotechnology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
Fermentation patterns of Escherichia coli HB101 carrying plasmids expressing cloned genes of Zymomonas mobilis pyruvate decarboxylase (PDC) and alcohol dehydrogenase li (ADH) were determined in glucose-limited complex medium in pH-controlled anaerobic batch cultivations. Time profiles of glucose, dry cell weight, succinate, formate, acetate, and ethanol were determined, as were the activities of ADH and PDC. Fluxes through the central carbon pathways were calculated for each construct utilizing exponential phase data on extracellular components and assuming quasi-steady state for intermediate metabolites. Overall biomass yields were greatest for cells expressing both PDC and ADH activities. Yields of carbon catabolite end products were similar for all PDC-expressing strains and different from those for other strains. Relative to its glucose uptake rate, the strain with greatest PDC and ADH activities produces formate and acetate more slowly and ethanol more rapidly than other strains. Strong influences of plasmid presence and metabolic coupling complicate detailed interpretations of the data.
Additional Material:
7 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/bit.260390110
