Proteomics for the Investigation of Surface-Exposed Proteins in Probiotics

Probiotics are commensal microorganisms that are present in the intestinal tract and in many fermented foods and positively affect human health, promoting digestion and uptake of dietary nutrients, strengthening intestinal barrier function, modulating immune response, and enhancing antagonism toward pathogens. The proteosurfaceome, i.e., the complex set of proteins present on the bacterial surface, is directly involved as leading actor in the dynamic communication between bacteria and host. In the last decade, the biological relevance of surface-exposed proteins prompted research activities exploiting the potentiality of proteomics to define the complex network of proteins that are involved in the molecular mechanisms at the basis of the adaptation to gastrointestinal environment and the probiotic effects. These studies also took advantages of the recent technological improvements in proteomics, mass spectrometry and bioinformatics that triggered the development of ad hoc designed innovative strategies to characterize the bacterial proteosurfaceome. This mini-review is aimed at describing the key role of proteomics in depicting the cell wall protein architecture and the involvement of surface-exposed proteins in the intimate and dynamic molecular dialogue between probiotics and intestinal epithelial and immune cells

Social environment elicits lateralized navigational paths in two populations of typically developing children

The current study provides the first evidence of human lateralized navigation of a social space within a naturalistic environment. We employed a quantitative, observational approach and report on a detailed set of nearly 700 independent navigational routes from two separate child populations consisting of over 300 typically developing children, aged five to fourteen years. The navigational path was considered across the sagittal plane (left, right) around three distinct target types (peer, adult and object). Both child populations expressed a significant bias for choosing a rightward navigational path around a human tar- get (e.g. peer, adult) and no lateral preference for navigation around fixed, inanimate objects. A rightward navigational path provides an advantage for the left visual field and the right hemisphere, facilitating both the production and perception of social-emotion stimuli. The findings are consistent with evidence from studies of non-human animal species demonstrating that the social environment elicits predictable lateralized behavior, and support an early evolutionary delineation of functional processing by the two hemispheres

Proteomics and Human Diseases

Proteomics, the large scale study of proteins and protein variations, contributes to a better understanding of the molecular basis of variability in susceptibility to diseases that are associated with genetic diversity and environmental factors. The development of proteomic technologies has permitted the unprecedented large-scale identification of proteins in any biological system. Human proteomics point out physiological conditions that could greatly impact on medicine. This knowledge has the potential to decode the pathogenic mechanisms underlying diseases, elucidate potential risk factors and molecular targets for drug development and therapeutic interventions and identify promising biomolecules that could be developed for diagnostic and prognostic purposes and for improved disease management strategies. Thus proteomics can translate basic scientific discoveries into the clinical practice for precision medicine. This report provides an overview of targeted proteomics in biomedical clinical science by focusing on current stateof-the-art relatively to advances in biomedical proteomic applications. Future prospective metaproteomics and proteogenomics studies are highlighted

Proteomics pattern associated with gingival oral squamous cell carcinoma and epulis: A case analysis

Objectives: Oral squamous cell carcinoma (OSCC) is the most common epithelial malignant neoplasm affecting the oral cavity. OSCC can mimic oral lesions of inflammatory origin with benign features, often leading to delay in diagnosis and treatment. Early detection is important to greatly increase the chances of a successful treatment. The present study reports a proteomic analysis of a gingival oral squamous cell carcinoma (G-OSCC) and an epulis. Materials and methods: Normal mucosae tissue, G-OSCC tissue, and epulis tissue as a comparative sample of benign nature were collected and immediately frozen in liquid nitrogen. Tissue-extracted proteins were separated by two-dimensional gel electrophoresis and subjected to image analysis. Proteins that showed a significant difference in the expression level in the G-OSCC tissue were identified by the nano-ESI-HPLC-MS/MS experiment and database searchi. Results and conclusion: The proteomic analysis of G-OSCC tissue enabled the identification of proteins that are potentially related to the disease; these proteins can be considered as signature molecules for diagnostic and prognostic tumor markers

Impact of aerobic and respirative life-style on Lactobacillus casei N87 proteome

Lactic acid bacteria (LAB) are used as starter, adjunct and/or probiotic cultures in fermented foods. Several species are recognized as oxygen-tolerant anaerobes, and aerobic and respiratory cultivations may provide them with physiological and technological benefits. In this light, mechanisms involved in the adaptation to aerobic and respiratory (supplementation with heme and menaquinone) growth conditions of the O2-tolerant strain Lactobacillus casei N87 were investigated by proteomics. In fact, in this bacterial strain, respiration induced an increase in biomass yield and robustness to oxidative, long-term starvation and freeze-drying stresses, while high concentrations of dissolved O2 (dO2 60%) negatively affected its growth and cell survival. Proteomic results well paralleled with physiological and metabolic features and clearly showed that aerobic life-style led to a higher abundance of several proteins involved in carbohydrate metabolism and stress response mechanisms and, concurrently, impaired the biosynthesis of proteins involved in nucleic acid formation and translation processes, thus providing evidence at molecular level of the significant damage to L.casei N87 fitness. On the contrary, the activation of respiratory pathways due to heme and menaquinone supplementation, led to a decreased amount of chaperones and other stress related proteins. These findings confirmed that respiration reduced oxidative stress condition, allowing to positively modulate the central carbohydrate and energy metabolism and improve growth and stress tolerance features. Results of this study could be potentially functional to develop competitive adjunct and probiotic cultures effectively focused on the improvement of quality of fermented foods and the promotion of human health

A case report of esophageal actinomycosis in an immunocompetent patient and review of the literature

Actinomycosis is a rare, chronic and slowly progressive granulomatous disease caused by Actinomyces spp., a Gram-positive anaerobic bacterium that rarely affects the esophagus. Although this infection is uncommon, it has been reported in both immunocompromised and immunocompetent individuals. The infection is often misdiagnosed because it can mimic other pathological conditions (like neoplasms and candidiasis), and Actinomyces is difficult to isolate because it requires specific growth conditions. However, actinomycosis has a favorable course if the microbiological diagnosis is timely. We report a case of esophageal actinomycosis in an immunocompetent 23-year-old man. The patient was admitted with symptoms of gastro-esophageal reflux disease (GERD), that had subsequently worsened. Histological and microbiological investigations revealed the presence of Actinomyces spp. A review of the literature regarding the clinical features, diagnosis, and management of this infection is also discussed

A distinctive protein signature induced by lysophosphatidic acid receptor 6 (LPAR6) expression in hepatocellular carcinoma cells

Hepatocellular carcinoma (HCC) is the most commonly diagnosed liver malignancy, ranking third in the overall global cancer-related mortality. A complex network of interacting proteins controls HCC growth and progression. Lysophosphatidic acid receptors (LPAR) are commonly overexpressed in HCC. In particular, we have previously reported that the expression of LPAR6 sustains tumorigenesis and growth of HCC and results in a poor prognosis in HCC patients. Here, we applied a comparative proteomic approach to compare protein expression in both LPAR6 expressing (HLE-LPAR6) and nonexpressing HCC cells (HLE-neo). We found changes in the expression levels of 19 proteins, which include carbohydrate metabolism enzymes, redox and detoxification enzymes, and gene-expression regulatory proteins. Our findings support the role of LPAR6 in controlling the expression of a distinctive protein signature in HCC cells, which can offer a valuable resource for the identification of potential theranostic biomarkers

<i>Lactobacillus acidophilus</i>—Rutin Interplay Investigated by Proteomics

<div><p>Dietary polyphenols are bioactive molecules that beneficially affect human health, due to their anti-oxidant, anti-inflammatory, cardio-protective and chemopreventive properties. They are absorbed in a very low percentage in the small intestine and reach intact the colon, where they are metabolized by the gut microbiota. Although it is well documented a key role of microbial metabolism in the absorption of polyphenols and modulation of their biological activity, molecular mechanisms at the basis of the bacteria-polyphenols interplay are still poorly understood. In this context, differential proteomics was applied to reveal adaptive response mechanisms that enabled a potential probiotic <i>Lactobacillus acidophilus</i> strain to survive in the presence of the dietary polyphenol rutin. The response to rutin mainly modulated the expression level of proteins involved in general stress response mechanisms and, in particular, induced the activation of protein quality control systems, and affected carbohydrate and amino acid metabolism, protein synthesis and cell wall integrity. Moreover, rutin triggered the expression of proteins involved in oxidation-reduction processes.This study provides a first general view of the impact of dietary polyphenols on metabolic and biological processes of <i>L</i>. <i>acidophilus</i>.</p></div

Decreased amount of vimentin N-terminal truncated proteolytic products in parkin-mutant skin fibroblasts

Vimentin, a member of cytoskeleton intermediate filaments proteins, plays a critical role in cell structure and dynamics. The present proteomic study reveals reduced amount of six different lengths, N-terminal truncated proteolytic products of vimentin, in the primary skin fibroblasts from two unrelated PD patients, as compared to control fibroblasts. The decreased amount of N-terminal truncated forms of vimentin in parkin-mutant fibroblasts, could contribute to impairment of cellular function, potentially contributing to the pathogenesis of Parkinson disease

Growth curves of <i>L</i>. <i>acidophilus</i> in control conditions and in the presence of rutin.

<p>(A) Growth curves of <i>L</i>. <i>acidophilus</i> obtained by plate counting. (B) Growth curves of <i>L</i>. <i>acidophilus</i> obtained measuring the optical density at 600 nm. Arrows indicate the times of bacterial cell collection for the further proteomic analyses. Values are the means of four independent experiments.</p