Curing of Plasmid pXO1 from Bacillus anthracis Using Plasmid Incompatibility

The large plasmid pXO1 encoding the anthrax toxin is important for the virulence of Bacillus anthracis. It is essential to cure pXO1 from B. anthracis to evaluate its role in the pathogenesis of anthrax infection. Because conventional methods for curing plasmids (e.g., curing agents or growth at elevated temperatures) can induce mutations in the host chromosomal DNA, we developed a specific and reliable method to eliminate pXO1 from B. anthracis using plasmid incompatibility. Three putative replication origins of pXO1 were inserted into a temperature-sensitive plasmid to generate three incompatible plasmids. One of the three plasmids successfully eliminated the large plasmid pXO1 from B. anthracis vaccine strain A16R and wild type strain A16. These findings provided additional information about the replication/partitioning of pXO1 and demonstrated that introducing a small incompatible plasmid can generate plasmid-cured strains of B. anthracis without inducing spontaneous mutations in the host chromosome

Low-salt restructured fish products from Atlantic mackerel (<i>Scomber scombrus</i>) with texture resembling turkey breast

Atlantic mackerel ( Scomber scombrus) is a pelagic and migratory species that is usually caught with other fish as bycatch. The aim of this work was to obtain low-salt restructured fish products from Atlantic mackerel resembling turkey breast using transglutaminase (0.2 U/g) as binder. NaCl concentration (0–20 g/kg), temperature (25–40 °C) and time of incubation (30–90 min) were assayed. The texture parameters (Warner–Bratzler force and Warner–Bratzler work) and expressible water were compared to those of turkey breast. Mathematical models were obtained to determine the effect of these variables on the texture of Atlantic mackerel restructured products. Optimal conditions to obtain a similar texture than turkey breast were found. The overall optimization point out that the treatment at 31.8 °C for 63.35 min using a NaCl concentration of 8.45 g/kg allowed to obtain restructured products from Atlantic mackerel with texture and expressible water similar to those of turkey breast. Color parameters ( L*, a* and b*) of the product were also similar to those of turkey breast. The results showed the feasibility of producing low-salt restructured products from Atlantic mackerel resembling turkey breast using transglutaminase.</jats:p

The Influence of Portion Size and Timing of Meals on Weight Balance and Obesity

This review focuses on the influence of portion size and temporal distribution of food intake on weight balance and obesity in adults. The inconsistency of definitions in the area of meal patterns is also discussed. The conclusion is that regular eating habits might facilitate weight balance, while unplanned snacking as well as consuming the major part of the energy intake at the end of the day seem to be unfavourable. Altogether, the research suggests that large portions promote over-consumption and, therefore, limiting portion size of energy dense foods and drinks with added sugar could be recommended. Even if more research is needed, these factors should be taken into consideration in recommendations for obesity prevention