Plasmid maintenance and recombinant cell fitness explored in bacterial colonies

• Published in: Biotechnology letters Vol. 23; no. 10; pp. 831 - 838
• Main Authors: CAZORLA, Daniel, FERRER-MIRALLES, Neus, FELIU, Jordi X, CARBONELL, Xavier, VILLAVERDE, Antonio
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer 01-05-2001; Springer Nature B.V
• Subjects: Bacteria; Biological and medical sciences; Biotechnology; E coli; Escherichia coli; Fundamental and applied biological sciences. Psychology; Genetic engineering; Genetic technics; lacZ gene; Methods. Procedures. Technologies; Microbiology; Miscellaneous; Synthetic digonucleotides and genes. Sequencing; Recombinant microorganism; Microorganism growth; Stability; Enzyme; Escherichia coli; Plasmid; Glycosidases; Microorganism culture; Bacteria; Hydrolases; O-Glycosidases; β-Galactosidase; Enterobacteriaceae; Fitness
• ISSN: 0141-5492; 1573-6776
• DOI: 10.1023/A:1010326125346

During growth of recombinant bacteria, irregular plasmid partitioning generates non-productive, plasmid-free cells whose proportion usually increases in the culture. For Escherichia coli producing engineered β-galactosidases, we have shown a coincidence between plasmid stability and the extension of white/blue areas within individual colonies on X-gal plates. In this context, a good correlation between plasmid permanence in colonies and parameters accurately describing the dynamics of plasmid-free cell population in liquid cultures has been observed. Moreover, the impact of lacZ gene engineering and the metabolic burden imposed by the encoded proteins has been evaluated through plasmid stability by simple image analysis, revealing an enhanced plasmid loss rate as the cells enter into the stationary phase that is modulated by the expression of particular recombinant genes.[PUBLICATION ABSTRACT]