BIOFILM FORMATION LACTOCOCCUS LACTIS SUBSP. LACTIS 502 IN PRESENCE OF EXOGENOUS NISIN
Aim: Discovery of the exogenous nisin action on biofilm formation and matrix polysaccharides content in Lactococcus lactis subsp. lactis 502. Materials and methods. As test there were organism used bacteria of strain Lactococcus lactis subsp. lactis 502 received from the collection of microorganisms...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Odessa I. I. Mechnikov National University
2015-09-01
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| Series: | Mìkrobìologìâ ì Bìotehnologìâ |
| Subjects: | |
| Online Access: | http://mbt.onu.edu.ua/article/view/53671 |
| Summary: | Aim: Discovery of the exogenous nisin action on biofilm formation and matrix polysaccharides content in Lactococcus lactis subsp. lactis 502. Materials and methods. As test there were organism used bacteria of strain Lactococcus lactis subsp. lactis 502 received from the collection of microorganisms of Belarussian State Technological University. Commercial preparation Nisaplin (Sigma-Aldrich Co.), containing 2.5 % of pure nisin was used as a source of nisin. The final concentration of nisin was 0.025–250 ng/ml. The cultivation was carried 48 hours at 30 °C in TDES medium in 48-well flat-bottomed plates Nuclon. The number of the planktonic cells was assessed spectrophotometrically. The biofilms were stained with crystal violet. The matrix polysaccharides were stained with congo red. Results. Nisin in concentrations exceeding 62.5 ng/ml has a pronounced inhibitory effect on biofilm formation and polysaccharide content in the matrix. When autoinducer concentrations were 125 and 250 ng/ml biofilm mass were only 11 % and 7 % compared to control and the level of polysaccharide in the matrix decreased by 3.6 and 8.3 times, respectively, in the presence of 125 and 250 ng/ml of nisin. Planktonic cells were less sensitive to the action of nisin. In the presence of two highest concentrations of the autoinducers their content was 60 % from control. The stimulatory effect of nisin was observed over a narrow range of concentrations. Biofilm weight increased 1.6-fold in the presence of nisin at the concentration of 2.5 ng/ml. The content of polysaccharides in the matrix increased by 20–24 % at the concentration of autoinducer 2.5–12.5 ng/ml. Conclusion. The obtained results suggest that high concentrations of nisin inhibit sensory kinase NisK, that, in turn, prevents gene activation of genes of quorum system L. lactis. |
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| ISSN: | 2076-0558 2307-4663 |