%0 Journal Article
%T Nisin Z Production by Wild Strains of Lactococcus lactis Isolated from Brazilian (Italian Type) Fermented Sausage
%A Baracat-Pereira
%A Maria Cristina
%A Birri
%A Dagim Jirata
%A Brede
%A Dag Anders
%A Moraes
%A C¨¦lia Alencar de
%A Nes
%A Ingolf F
%A Queiroz
%A Marisa Vieira de
%A Saraiva
%A Margarete Alice Fontes
%J -
%D 2020
%R https://doi.org/10.1155/2020/9309628
%X In this study, five bacteriocin-producing Lactococcus lactis strains were identified from different naturally fermented Brazilian sausages. Ion exchange and reversed-phase chromatographies were used to purify the bacteriocins from culture supernatant of the five strains. Mass spectrometry (MALDI-TOF/TOF) showed that the molecular masses of the bactericoins from L. lactis ID1.5, ID3.1, ID8.5, PD4.7, and PR3.1 were 3330.567£¿Da, 3330.514£¿Da, 3329.985£¿Da, 3329.561£¿Da, and 3329.591£¿Da, respectively. PCR product sequence analysis confirmed that the structural genes of bacteriocins produced by the five isolates are identical to the lantibiotic nisin Z. Optimal nisin Z production was achieved in tryptone and casein peptone, at pH 6.0 or 6.5. The most favorable temperatures for nisin Z production were 25¡ãC and 30¡ãC, and its production was better under aerobic than anaerobic condition. The type of carbon source appeared to be an important factor for nisin Z production. While sucrose was found to be the most efficient carbon source for nisin Z production by four L. lactis isolates, fructose was the best for one isolate. Lactose was also a good energy source for nisin Z production. Surprisingly, glucose was clearly the poorest carbon source for nisin Z production. The five isolates produced different amounts of the bacteriocin, L. lactis ID1.5 and ID8.5 isolates being the best nisin Z producers. DNA sequence analysis did not reveal any sequence differences in the nisZ and nisF promoter regions that could explain the differences in nisin Z production, suggesting that there should be other factors responsible for differential nisin Z production by the isolates
%U https://www.hindawi.com/journals/ijmicro/2020/9309628/