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MisL is a Salmonella enterica serotype Typhimurium fibronectin binding protein whose expression is induced during infection of mice. T-POP transposon mutagenesis identified marT as a positive regulatory element controlling expression of a misL::lacZYA transcriptional fusion. Gel shift analysis identified MarT as a transcriptional activator of the misL promoter.

The technological and probiotic characteristics of a number of Lactobacillus plantarum strains (previously isolated and identified from traditionally produced fermented vegetables) were compared, with the aim of identifying potential starter cultures to be used for the fermentation of vegetables. The L. plantarum strains were differentiated by their plasmid profiles; 12 separate strains with different plasmid profiles were examined. Other than survival in different concentrations of NaCl, the technological characteristics of all the strains examined were similar. However, strain-dependent variations in probiotic features were observed, with low pH in particular found to be a restrictive condition for all strains. The results indicated that, among the tested strains, L. plantarum 3 and 22 had good technological properties whereas L. plantarum 66 was significantly efficient in terms of probiotic features. Overall, L. plantarum 22 was found to be the most appropriate strain due to its combination of technological and probiotic properties.

Nisin is a bacteriocin produced by Lactococcus lactis that has been approved by the Food Drug Administration for utilization as a GRAS status food additive. Nisin can inhibit spore germination and demonstrates antimicrobial activity against Listeria, Clostridium, Staphylococcus, and Bacillus species. Under some circumstances, it plays an immune modulator role and has a selective cytotoxic effect against cancer cells, although it is notable that the high production cost of nisin-a result of the low nisin production yield of producer strains-is an important factor restricting intensive use. In recent years, production of nisin has been significantly improved through genetic modifications to nisin producer strains and through innovative applications in the fermentation process. Recently, 15,400 IU ml nisin production has been achieved in L. lactis cells following genetic modifications by eliminating the factors that negatively affect nisin biosynthesis or by increasing the cell density of the producing strains in the fermentation medium. In this review, innovative approaches related to cell and fermentation systems aimed at increasing nisin production are discussed and interpreted, with a view to increasing industrial nisin production.