Conservation of σ28-Dependent Non-Coding RNA Paralogs and Predicted σ54-Dependent Targets in Thermophilic Campylobacter Species.

Assembly of flagella requires strict hierarchical and temporal control via flagellar sigma and anti-sigma factors, regulatory proteins and the assembly complex itself, but to date non-coding RNAs (ncRNAs) have not been described to regulate genes directly involved in flagellar assembly. In this study we have investigated the possible role of two ncRNA paralogs (CjNC1, CjNC4) in flagellar assembly and gene regulation of the diarrhoeal pathogen Campylobacter jejuni. CjNC1 and CjNC4 are 37/44 nt identical and predicted to target the 5' untranslated region (5' UTR) of genes transcribed from the flagellar sigma factor σ54.

A bacterial homolog of a eukaryotic inositol phosphate signaling enzyme mediates cross-kingdom dialog in the mammalian gut.

Dietary InsP6 can modulate eukaryotic cell proliferation and has complex nutritive consequences, but its metabolism in the mammalian gastrointestinal tract is poorly understood. Therefore, we performed phylogenetic analyses of the gastrointestinal microbiome in order to search for candidate InsP6 phosphatases. We determined that prominent gut bacteria express homologs of the mammalian InsP6 phosphatase (MINPP) and characterized the enzyme from Bacteroides thetaiotaomicron (BtMinpp).

Intestinal intraepithelial lymphocyte-enterocyte crosstalk regulates production of bactericidal angiogenin 4 by Paneth cells upon microbial challenge.

Antimicrobial proteins influence intestinal microbial ecology and limit proliferation of pathogens, yet the regulation of their expression has only been partially elucidated. Here, we have identified a putative pathway involving epithelial cells and intestinal intraepithelial lymphocytes (iIELs) that leads to antimicrobial protein (AMP) production by Paneth cells. Mice lacking γδ iIELs (TCRδ(-/-)) express significantly reduced levels of the AMP angiogenin 4 (Ang4).

Structure and biosynthesis of two exopolysaccharides produced by Lactobacillus johnsonii FI9785.

Exopolysaccharides were isolated and purified from Lactobacillus johnsonii FI9785, which has previously been shown to act as a competitive exclusion agent to control Clostridium perfringens in poultry. Structural analysis by NMR spectroscopy revealed that L. johnsonii FI9785 can produce two types of exopolysaccharide: EPS-1 is a branched dextran with the unusual feature that every backbone residue is substituted with a 2-linked glucose unit, and EPS-2 was shown to have a repeating unit with the following structure: -6)-α-Glcp-(1-3)-β-Glcp-(1-5)-β-Galf-(1-6)-α-Glcp-(1-4)-β-Galp-(1-4)-β-Glcp-(1-.

Effect of acidic pH on flow cytometric detection of bacteria stained with SYBR Green I and their distinction from background.

Unspecific background caused by biotic or abiotic particles, cellular debris, or autofluorescence is a well-known interfering parameter when applying flow cytometry to the detection of microorganisms in combination with fluorescent dyes. We present here an attempt to suppress the background signal intensity and thus to improve the detection of microorganisms using the nucleic acid stain SYBR Green I. It has been observed that the fluorescent signals from SYBR Green I are greatly reduced at acidic pH.