| 초록 |
As an important industrial strain producing amino acids, biochemical, and recombinant protein, Corynebacterium glutamicum has been developed by molecular and metabolic engineering. In this work, we implemented adaptive laboratory evolution, a powerful methodology for manufacturing bacteria. Cells expressing eGFP with constitutive promoter in plasmid system were evolved by fluorescence-activated cell sorter. Artificial strong selection pressure was high fluorescence intensity. Approximately 7-fold the fluorescence intensity was shown in evolved strain. A nonsense mutation was found only in parB of pCG1 origin, cryptic plasmid of C. glutamicum by switching to stop codon or frameshift. These mutation leads to an increase in plasmid copy number. This mutant plasmid had an 11-fold plasmid copy number than that of wild type plasmid. In addition, it had high segregational stability under 60 generation cultivation without antibiotic. |
