Continuous nisin production with bioengineered Lactococcus lactis strains
| Autor: | F. Özçelik, Mustafa Akçelik, Nefise Akkoç, Ömer Şimşek, Ahmet Hilmi Çon, Per E. J. Saris |
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| Rok vydání: | 2009 |
| Předmět: |
culture medium
Regulation genes Continuous fermentation Bioengineering chemistry Applied Microbiology and Biotechnology fructose chemistry.chemical_compound Bacteriocin controlled study genetics Culture Media/metabolism Fermentation Genetic Engineering Kinetics Lactococcus lactis/chemistry/*genetics/*metabolism Nisin/chemistry/*metabolism Nisin genetic engineering bioengineering nonhuman biology Lactococcus lactis Immunity genes article Fructose gene control bacterial strain biology.organism_classification Streptococcaceae Culture Media Dilution Biochemistry bacteria nisin metabolism Bacteria Biotechnology |
| Zdroj: | Journal of Industrial Microbiology & Biotechnology. 36:863-871 |
| ISSN: | 1476-5535 1367-5435 |
| DOI: | 10.1007/s10295-009-0563-6 |
| Popis: | Nisin production in continuous cultures of bioengineered Lactococcus lactis strains that incorporate additional immunity and regulation genes was studied. Highest nisin activities were observed at 0.2 h-1 dilution rate and 12.5 g l-1 fructose concentration for all strains. Recombinant strains were able to produce greater amounts of nisin at dilution rates below 0.3 h-1 compared to the control strain. However, this significant difference disappeared at dilution rates of 0.4 and 0.5 h-1. For the strains LL27, LAC338, LAC339, and LAC340, optimum conditions for nisin production were determined to be at 0.29, 0.26, 0.27, and 0.27 h-1 dilution rates and 11.95, 12.01, 11.63, and 12.50 g l-1 fructose concentrations, respectively. The highest nisin productivity, 496 IU ml -1 h-1, was achieved with LAC339. The results of this study suggest that low dilution rates stabilize the high specific nisin productivity of the bioengineered strains in continuous fermentation. Moreover, response surface methodology analysis showed that regulation genes yielded high nisin productivity at wide ranges of dilution rates and fructose concentrations. © 2009 Society for Industrial Microbiology. |
| Databáze: | OpenAIRE |
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