Stress Response Kinetics of Two Nisin Producer Strains of Lactococcus lactis spp. lactis

2009-08-01
Simsek, Oemer
BUZRUL, Sencer
Akkoc, Nefise
Alpas, Hami
Akcelik, Mustafa
The purpose of this study is to determine the survival and nisin production behaviors of two strains of Lactococcus lactis under different stress conditions that represent the food ecosystem. In this respect, the survival ratios of two nisin producers were determined under different pH, temperature, NaCl, and bile salt concentrations. Then, nisin production levels of the strains were determined at each stress conditions. Both strains had similar growth or inactivation patterns under the same stress conditions. NaCl and bile salt stresses on the survival ratio of the strains could be successfully described by the exponential decay function, whereas Gaussian function produced good fits for temperature and pH stresses. The nisin activity of two nisin producers (in their mid-exponential and/or early stationary phase) decreased dramatically under all stress conditions, except osmotic (NaCl) and low temperature applications. The results of this study showed that two nisin producers had similar adaptive responses under severe stress conditions, which could be described by appropriate mathematical equations. Moreover, the effect of harsh environment on the nisin activity of L. lactis strains depends on the stress factors applied.
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY

Suggestions

Expression of chitinase A (chiA) gene from a local isolate of Serratia marcescens in Coleoptera-specific Bacillus thuringiensis
Okay, S.; Tefon, B. E.; ÖZKAN, MELEK; Özcengiz, Gülay (Wiley, 2008-01-01)
Aims: The present study focused on cloning and expression of chiA gene from a highly chitinolytic local isolate of Serratia marcescens in an anti-Coleopteran Bacillus thuringiensis and comparison of the characteristics of the native and recombinant ChiAs.
Effect of starvation on the adhesive properties of xenobiotic degrading bacteria
Sanin, SL; Sanin, Faika Dilek; Bryers, JD (Elsevier BV, 2003-01-31)
The purpose of this study was to observe the effects of different starvation conditions on the surface characteristics and adhesive properties of bacteria. Three pure culture xenobiotic degrading bacteria were used in this study: Pseudomonas sp. strain A, Pseudomonas sp. strain D and Rhodococcus corallinus strain 11. These microorganisms were selected for to their ability to degrade cyanuric acid, which is a derivative of s-Triazine, a common herbicide. These microorganisms were separately starved for carbo...
Effects of pH and feeding strategy on metabolite profiling of beta-lactamase producing bacillus licheniformis
İler, Nazar; Çalık, Pınar; Department of Chemical Engineering (2005)
In this study, the effects of pH and different feeding modes on beta-lactamase production and cell metabolism were investigated with Bacillus licheniformis (ATCC 25972). For this purpose, first, the effects of pH on beta-lactamase activity, cell formation, substrate consumption, as well as intracellular sodium, potassium, ammonium ion, amino acid and organic acid concentrations were investigated in V= 3.0 dm3 batch bioreactors consisting of temperature, pH, foam, stirring rate and dissolved oxygen controls....
Vector construction for transformation of tobacco with a NAC-type transcription factor, TaNAC69-1
Eroğlu, Ayten; BALOĞLU, MEHMET CENGİZ; Yucel, Meral (2016-08-10)
NAC type transcription factors are a large family of plant transcription factors related to defense, development, biotic and abiotic responses of plants. To construct vectors for tobacco transformation, traditional and Gateway cloning technology were used. For traditional cloning, firstly TaNAC69-1 gene was isolated from Triticum aestivum L. cv. Yuregir-89. After cDNA synthesis, TaNAC69-1 gene was cloned into pJET1.2 cloning vector. To transfer the gene into dicot expression vector, pORE-E3, both pJET1.2 a...
Growth of agriculturally important Pseudomonas spp. and Azotobacter Chroococcum on beer waste and observation of their survival in peat
Abat, Benek; Hamamcı, Haluk; Department of Food Engineering (2006)
In this study agriculturally important Pseudomonas spp. which may solubilize phosphate and Azotobacter chroococcum which can fix atmospheric nitrogen were grown on waste beer with 4 different concentrations and conditions for best growth were determined. Having potential of use as biofertilizers, they were put in the carrier material peat and survivals of them were observed for 3 months at three different temperatures. Biofertilizer can be defined as a substance which contains living microorganisms which, w...
Citation Formats
O. Simsek, S. BUZRUL, N. Akkoc, H. Alpas, and M. Akcelik, “Stress Response Kinetics of Two Nisin Producer Strains of Lactococcus lactis spp. lactis,” APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY, pp. 387–397, 2009, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/47367.