Identification of Lactic Acid Bacteria from Poultry Feces: Evidence on Anti-Campylobacter and Anti-Listeria Activities

ABSTRACT Forty-five strains of lactic acid bacteria were isolated from poultry feces sampled from an indus-trial farm located in the Nantes area (France), and most of them belong to the Streptococcus or Lactobacillus genus according to the results obtained by Galerie API and mo-lecular methods. The most representative lactic acid bac-teria strains were screened for antibacterial compound production against 2 indicator organisms (Listeria innocua F and Campylobacter jejuni 11168) by means of the agar diffusion test. Strain S37, identified as Enterococcus faecalis

Biodiversity and Phylogenetic Relationships of Novel Bacteriocinogenic Strains Isolated from Animal’s Droppings at the Zoological Garden of Lille, France

International audienceThis study aimed at exploring droppings of animals living in captivity in the zoological garden (Zoo) of Lille (France), as novel sources of bacteriocinogenic strains. A collection of 295 bacterial isolates was constituted from droppings of capybara, alpaca, muntjac, zebra, tapir, rhinoceros, binturong, armadillo, saki monkey and cockatoo. Of 295 isolates, 51 exhibited antagonism against a panel of pathogenic target bacteria like Escherichia coli MC4100, Clostridium perfringens DSM 756 and Salmonella enterica subsp. enterica Newport ATCC6962. Remarkably, within this collection, only 2 Gram-negative bacilli exhibited activity against E. coli MC4100 strain used as target organism. Then, the 16S rDNA sequencing revealed these thereafter cited species, Pediococcus pentosaceus, Weissella cibaria, E. coli, Lactobacillus reuteri, Enterococcus hirae and Enterococcus faecalis. Characterization of this antagonism has revealed 11 strains able producing extracellular protease-sensitive inhibitory compounds. These strains included E. coli ICVB442 and ICVB443, Ent. faecalis ICVB472, ICVB474, ICVB477 ICVB479, ICVB481, ICVB497 and ICVB501 and Ped. pentosaceus ICVB491 and ICVB492. The genomes of the 5 most promising bacteriocinogenic strains were sequenced and analysed with Bagel4 software. Afterwards, this bioinformatics analysis permitted to locate genes encoding bacteriocins like colicin Y (E. coli), enterocin 1071A, enterocin 107 B (Ent. faecalis) and penocin A (Ped. pentosaceus), associating the above-mentioned antibacterial activity of proteinaceous nature to possible production of bacteriocins. All these results enabled us to select different bacteriocinogenic strains for a further characterization in terms of beneficial traits

Elevation of Peripheral BDNF Promoter Methylation Links to the Risk of Alzheimer's Disease

Brain derived neurotrophic factor (BDNF) has been known to play an important role in various mental disorders or diseases such as Alzheimer's disease (AD). The aim of our study was to assess whether BDNF promoter methylation in peripheral blood was able to predict the risk of AD. A total of 44 AD patients and 62 age- and gender-matched controls were recruited in the current case-control study. Using the bisulphite pyrosequencing technology, we evaluated four CpG sites in the promoter of the BDNF. Our results showed that BDNF methylation was significantly higher in AD cases than in the controls (CpG1: p = 10.021; CpG2: p = 0.002; CpG3: p = 0.007; CpG4: p = 0.005; average methylation: p = 0.004). In addition, BDNF promoter methylation was shown to be significantly correlated with the levels of alkaline phosphatase (ALP), glucose, Lp(a), ApoE and ApoA in males (ALP: r = -0.308, p = 0.042; glucose: r = -0.383, p = 0.010; Lp(a): r = 0.333, p = 0.027; ApoE: r = -0.345, p = 0.032;), ApoA levels in females (r = 0.362, p = 0.033), and C Reactive Protein (CRP) levels in both genders (males: r = -0.373, p = 0.016; females: r = -0.399, p = 0.021). Our work suggested that peripheral BDNF promoter methylation might be a diagnostic marker of AD risk, although its underlying function remains to be elaborated in the future