Influence of growth conditions on plasmid DNA production.
The obtention of high yields of purified plasmid DNA is viewed as an essential issue to be considered towards efficient production of DNA vaccines and therapeutic plasmids. In this work, Escherichia coli DH5alpha bearing the pVAX1-LacZ plasmid was grown in a developed semi-defined medium at different temperatures and tryptone concentrations. Analysis of pDNA yields and E. coli morphology revealed that at higher temperatures (37 and 40 degrees C), higher specific yields and E. coli filamentation were obtained. However, the best results were achieved when a lower tryptone concentration was used. This approach was shown to be a powerful tool to promote plasmid amplification, keeping the desirable plasmid structure, and favoring the attainment of quality. Our results suggest that by using tryptone alone as an amino acid source, pDNA amplification was improved and a specific yield of 20.43 mg pDNA/g dcw was achieved, proving that this strategy can improve pDNA yield even at a small scale.
Silva
Filomena
F
Centro de Investigacao em Ciencias da Saude, Universidade da Beira Interior, Avenida Infante D. Henrique, 6200-506 Covilha, Portugal.
Passarinha
Luís
L
Sousa
Fani
F
Queiroz
João A
JA
Domingues
Fernanda C
FC
D018929:Cell Culture Techniques / Q000379:methods; D003470:Culture Media / Q000737:chemistry; D004261:DNA Replication; D004269:DNA, Bacterial / Q000096:biosynthesis* / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D005285:Fermentation; D007218:Industrial Microbiology / Q000379:methods; D021141:Nucleic Acid Amplification Techniques / Q000379:methods; D010461:Peptones / Q000737:chemistry; D010957:Plasmids / Q000096:biosynthesis* / Q000235:genetics; D013696:Temperature; D019444:Vaccines, DNA / Q000096:biosynthesis
D003470:Culture Media; D004269:DNA, Bacterial; D010461:Peptones; D019444:Vaccines, DNA; C001830:tryptones