ISSN:
0006-3592
Keywords:
Chemistry
;
Biochemistry and Biotechnology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
An auxotrophic mutant of Saccharomyces cerevisiae, containing a recombinant 2-μ-based plasmid, was grown in selective media in continuous culture. The plasmid retained the ability to synthesize acid phosphatase as product, which was deleted from the host. Plasmid loss was followed at various dilution rates, and the level of plasmid expression was controlled by changing the β-glycero/inorganic phosphate ratio.Some interesting trends were observed. As the level of plasmid expression was raised, the stability dropped markedly. Since acid phosphatase expression is regulated at the level of transcription, it is possible that increased transcription interfered with plasmid replication, hindered segregation, or overburdened the cell's DNA repair capability. It was also observed that plasmid stability was substantially increased at high growth rates. At dilution rates of 0.3 and 0.37 h-1, feeding only inorganic phosphate, the plasmid was completely stable.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/bit.260290211
