The effect of different concentrations of nisin on DnaK-overproducing Lactococcus lactis strains while growing at 40°C was examined. The plasmid pNZ-8048 which has a nisin promoter was used as a vector for transformation and expression of heterologous or homologous DnaK into L. lactis NZ9000. The transformants were then induced with different concentration of nisin and allowed to grow in presence of nisin. It was found that nisin, the antimicrobial peptide used for induction of DnaK-overexpression, itself conferred a lower but significant stress to the strains. Escherichia coli DnaK (DnaK Eco)-overexpressing cells showed better tolerance to nisin than L. lactis DnaK (DnaK Lla) and T. halophilus DnaK (DnaK Tha)-overexpressing cells. However, all DnaK-overexpressing strains showed better tolerance than the cells without DnaK overexpression. These findings suggest the possibility for a relationship of DnaK protein and tolerance to different antimicrobial peptides.
|Number of pages||10|
|Journal||American Journal of Biochemistry and Molecular Biology|
|Publication status||Published - Feb 21 2012|
All Science Journal Classification (ASJC) codes
- Biochemistry, Genetics and Molecular Biology(all)