Spongiibacter marinus gen. nov., sp. nov., a halophilic marine bacterium isolated from the boreal sponge Haliclona sp. 1

Strain HAL40bT was isolated from the marine sponge Haliclona sp. 1 collected at the Sula Ridge off the Norwegian coast and characterized by physiological, biochemical and phylogenetic analyses. The isolate was a small rod with a polar flagellum. It was aerobic, Gram-negative and oxidase- and catalase-positive. Optimal growth was observed at 20–30 °C, pH 7–9 and in 3 % NaCl. Substrate utilization tests were positive for arabinose, Tween 40 and Tween 80. Enzyme tests were positive for alkaline phosphatase, esterase lipase (C8), leucine arylamidase, acid phosphatase, naphthol-AS-BI-phosphohydrolase and N-acetyl-β-glucosaminidase. The predominant cellular fatty acid was C17 : 1 ω8, followed by C17 : 0 and C18 : 1 ω7. Analysis by matrix-assisted laser desorption/ionization time-of-flight MS was used to characterize the strain, producing a characteristic low-molecular-mass protein pattern that could be used as a fingerprint for identification of members of this species. The DNA G+C content was 69.1 mol%. Phylogenetic analysis supported by 16S rRNA gene sequence comparison classified the strain as a member of the class Gammaproteobacteria. Strain HAL40bT was only distantly related to other marine bacteria including Neptunomonas naphthovorans and Marinobacter daepoensis (type strain sequence similarity >90 %). Based on its phenotypic, physiological and phylogenetic characteristics, it is proposed that the strain should be placed into a new genus as a representative of a novel species, Spongiibacter marinus gen. nov., sp. nov.; the type strain of Spongiibacter marinus is HAL40bT (=DSM 17750T =CCUG 54896T)

Comparison of geometric morphometric outline methods in the discrimination of age-related differences in feather shape

BACKGROUND: Geometric morphometric methods of capturing information about curves or outlines of organismal structures may be used in conjunction with canonical variates analysis (CVA) to assign specimens to groups or populations based on their shapes. This methodological paper examines approaches to optimizing the classification of specimens based on their outlines. This study examines the performance of four approaches to the mathematical representation of outlines and two different approaches to curve measurement as applied to a collection of feather outlines. A new approach to the dimension reduction necessary to carry out a CVA on this type of outline data with modest sample sizes is also presented, and its performance is compared to two other approaches to dimension reduction. RESULTS: Two semi-landmark-based methods, bending energy alignment and perpendicular projection, are shown to produce roughly equal rates of classification, as do elliptical Fourier methods and the extended eigenshape method of outline measurement. Rates of classification were not highly dependent on the number of points used to represent a curve or the manner in which those points were acquired. The new approach to dimensionality reduction, which utilizes a variable number of principal component (PC) axes, produced higher cross-validation assignment rates than either the standard approach of using a fixed number of PC axes or a partial least squares method. CONCLUSION: Classification of specimens based on feather shape was not highly dependent of the details of the method used to capture shape information. The choice of dimensionality reduction approach was more of a factor, and the cross validation rate of assignment may be optimized using the variable number of PC axes method presented herein

The biodiversity hypothesis and immunotolerance in allergy.

Background: The human immune system is capable of detecting a multitude of substances and organisms in the environment and responding to these in a variety of ways. This includes immune responses to pathogens, on the one hand, and immunotolerance in the form of immunoregulatory responses, resulting in either the termination of immune responses or in tolerance to harmless and endogenous substances, on the other. The development of immunotolerance is an active process that is essentially characterized by interaction with microbiota and environmental components and is primarily mediated by regulatory T cells. Methods: This article provides an overview of selected scientific articles and is addressed also to non-specialists. It is based on a literature search in PubMed, specialist databases, and guidelines. Results: According to the diversity hypothesis, exposure in early childhood to broad biodiversity is now considered to reduce the risk of developing allergic diseases. Conclusion: Therefore, tolerance induction emerges in allergology not only as a potential concept for prevention, but also as a treatment approach in atopic diseases

Cutaneous barriers and skin immunity.

The skin barrier provides us with several lines of protection from outside hazards. Its most outward layers, the stratum corneum and the epidermis seal our body with an acidic, dry, and rather cool surface, hostile to microbes. Yet, there are also fine-tuned interactions between the mostly commensal microbiota on top of the skin surface, with underlying epidermal cells as well as the immune system, to preserve a healthy steady state and to initiate repair processes when necessary. We take a concise look at the recent insights on the inner workings of this complex barrier

Induction of IL-10-balanced immune profiles following exposure to LTA from <em>Staphylococcus&nbsp;epidermidis</em>.

Staphylococcus&nbsp;epidermidis colonises human skin without apparent inflammation, but a dominance of S.&nbsp;epidermidis and S.&nbsp;aureus is characteristic of cutaneous microbial dysbiosis in atopic dermatitis (AD). While S.&nbsp;aureus can trigger AD, the role of S.&nbsp;epidermidis is less understood. We characterised consequences of innate immune sensing of lipoteichoic acid (LTA) preparations derived from S.&nbsp;epidermidis (epi-LTA) or S.&nbsp;aureus (aureus-LTA). Therefore, dendritic cell (DC) activation and consecutive priming of antigen-specific T cells following exposure of DC to epi-LTA or aureus-LTA were investigated. Mimicking acute AD, exposure of DC to IL-4 and LTAs was analysed. Exposure to epi-LTA or aureus-LTA activated human immune cells and murine dendritic cells (DCs) via TLR2/MyD88, however, resulting in divergent immune profiles. Differences between LTAs were significant for IL-6, IL-12p40 and IL-12p70 but not for IL-10, which was best reflected by the IL-12p70-to-IL-10 ratio being IL-10-balanced for epi-LTA but pro-inflammatory for aureus-LTA. LTA-exposed DCs activated CD4+ T cells; however, while T-cell-derived IL-10 was equivalent between LTAs, IFN-γ and IL-17 were significantly higher for aureus-LTA. Mimicking acute AD by exposing DCs to IL-4 and LTAs revealed that IL-4 significantly and uniformly suppressed epi-LTA-induced cytokine production, keeping the IL-12p70-to-IL-10 ratio balanced. In contrast, exposure of DCs to aureus-LTA and IL-4 enhanced IL-12p70 but suppressed IL-10 levels, further unbalancing the IL-12p70-to-IL-10 ratio. These data demonstrate opposing immune consequences following exposure to staphylococcal LTAs. Epi-LTA induced IL-10-balanced, aureus-LTA pro-inflammatory immune profiles

Carboxylative efficacy of trans and cis MK7 and comparison with other vitamin K isomers

Carboxylative enzymes are involved in many pathways and their regulation plays a crucial role in many of these pathways. In particular, γ-glutamylcarboxylase (GGCX) converts glutamate residues (Glu) into γ-carboxyglutamate (Gla) of the vitamin K-dependent proteins (VKDPs) activating them. VKDPs include at least 17 proteins involved in processes such as blood coagulation, blood vessels calcification, and bone mineralization. VKDPs are activated by the reduced form of vitamin K, naturally occurring as vitamin K1 (phylloquinone) and K2 (menaquinones, MKs). Among these, MK7 is the most efficient in terms of bioavailability and biological effect. Similarly to other trans isomers, it is produced by natural fermentation or chemically in both trans and cis. However, the efficacy of the biological effect of the different isomers and the impact on humans are unknown. Our study assessed carboxylative efficacy of trans and cis MK7 and compared it with other vitamin K isomers, evaluating both the expression of residues of carboxylated Gla-protein by western blot analysis and using a cell-free system to determine the GGCX activity by HPLC. Trans MK7H2 showed a higher ability to carboxylate the 70 KDa GLA-protein, previously inhibited in vitro by warfarin treatment. However, cis MK7 also induced a carboxylation activity albeit of a small extent. The data were confirmed chromatographically, in which a slight carboxylative activity of cis MK7H2 was demonstrated, comparable with both K1H2 and oxidized trans MK7 but less than trans MK7H2. For the first time, a difference of biological activity between cis and trans configuration of menaquinone-7 has been reported

Natural Staphylococcus aureus-derived peptidoglycan fragments activate NOD2 and act as potent costimulators of the innate immune system exclusively in the presence of TLR signals.

Innate immune sensing of Staphylococcus aureus unravels basic mechanisms leading to either effective antibacterial immune responses or harmful inflammation. The nature and properties of S. aureus-derived pathogen-associated molecular pattern (PAMPs) are still not completely understood. We investigated the innate immune sensing of peptidoglycan (PGN) structures and subsequent immune consequences. Macromolecular PGN (PGN(polymer)) preparations activated NF-κB through human Toll-like receptors 2 (TLR2), as shown by luciferase reporter assays, and induced murine dendritic cell (DC) maturation and cytokine production. In contrast, PGN(polymer) from lgt-mutant S. aureus failed to stimulate human TLR2, demonstrating that lipoproteins within the macromolecular structures of PGN(polymer), but not PGN itself, activate TLR2. Thus, HPLC-purified monomeric PGN (PGN(monomer)) structures were investigated. Strikingly, PGN(monomer) completely lacked NF-κB activation, lacked TLR2 activity, and failed to functionally activate murine DCs. However, PGN(monomer) in concert with various TLR ligands most effectively stimulated DCs to up-regulate IL-12p70 and IL-23 by ≥3- to 5-fold. Consequently, DCs coactivated by PGN(monomer) markedly up-regulated Th1 and Th17 while suppressing Th2 cell priming. Notably, PGN(monomer) failed to coactivate NOD2(-/-) DCs. This demonstrates that PGN(monomer) is a natural ligand of NOD2, which was previously only demonstrated for synthetic compounds like muramyl dipeptide. Interestingly, murine DCs lacking TLR2 remained mute in response to the combinative immune sensing of S. aureus-derived PAMPs, including PGN(monomer), providing for the first time an explanation of why S. aureus can colonize the nasal mucosa in the absence of inflammation. This is very likely based on the lack of TLR2 expression in mucosal epithelial cells under normal conditions, which determines the unresponsiveness to S. aureus PAMPs