Bacillus species are frequently used as bacterial workhorses in industrial microbial cultivation for production of probiotic compounds and antibiotics. Bacterial secretory proteins are known to perform "remote-control" functions, such as the provision of nutrients, detoxification of the environment, and killing of potential competitors. A previous proteomic study carried out in our laboratory examined cell proteins extracted from four closely related isogenic B. Clausii strain, used to produce a commercial probiotic preparation and led to the recognition of a number of proteins differentially expressed in the four strains. Here, we report a proteomic study of the secretome, i.e. the complement of extracellular secreted proteins, of the four B. clausii strains. The main objective of this study was to characterize the proteins actively secreted including secreted enzyme that can be useful in industry and domestic life and metabolic bottlenecks that can contribute to improve process optimization of their production. The electropherogram of the four B. clausii secretomes show more than 400 protein spots separated by two-dimensional gel electrophoresis (2-DE). More pronounced differences were revealed at the expression level of specific proteins, some of which represent the most abundant secreted proteins. The different expression pattern of proteins in the four secretomes demonstrates that the B. clausii strains, which are characterized by a notable low level of intraspecific genome diversity, present distinct pattern of protein secretion.

This study presents the effect of all-trans retinoic acid (ATRA) on cell growth and respiratory chaincomplex I in human keratinocyte cultures. Keratinocyte treatment results in increased level of GRIM-19 and other subunits of complex I, in particular of their carbonylated forms, associated with inhibitionof its enzymatic activity. The results show that in keratinocytes ATRA-promoted phosphatase activitycontrols the proteostasis and activity of conplex I.

Proteomic analysis shows that treatment of keratinocytes cultures with all trans retinoic acid (ATRA), under condition in which it inhibits cell growth, results in marked decrease of the level of the F1-beta subunit of the catalytic sector of the mitochondrial FoF1 ATP synthase complex. Enzymatic analysis shows in ATRA-treated keratinocytes a consistent depression of the ATPase activity, with decreased olygomycin sensitivity, indicating an overall alteration of the ATP synthase complex. These findings, together with the previously reported inhibition of respiratory complex I, show that depression of the activity of oxidative phosphorylation enzymes is involved in the cell growth inhibitory action of ATRA. (C) 2016 Elsevier Inc. All rights reserved.

Parkinson's disease (PD) is the most common neurodegenerative movement disorder caused primarily by selective degeneration of the dopaminergic neurons in substantia nigra. In this work the proteomes extracted from primary fibroblasts of two unrelated, hereditary cases of PD patients, with different parkin mutations, were compared with the proteomes extracted from commercial adult normal human dermal fibroblasts (NHDF) and primary fibroblasts from the healthy mother of one of the two patients. The results show that the fibroblasts from the two differen tcases of parkin-mutant patients display analogous alterations in the expression level of proteins involved in different cellular functions, like cytoskeleton structure-dynamics, calcium homeo- stasis, oxidative stress response and protein and RNA processing.

A comparative proteomic approach, using two dimensional gel electrophoresis and mass spectrometry, has been developed to compare and elucidate the differences among the cellular proteomes of four closely related isogenic O/C, SIN, N/R and T, B. clausii strains during both exponential and stationary phases of growth.Image analysis of the electropherograms reveals a high degree of concordance among the four proteomes, some proteins result, however, differently expressed. The proteins spots exhibiting high different expression level were identified, by mass-spectrometry analysis, as alcohol dehydrogenase (ADHA, EC1.2.1.3; ABC0046 isoform) aldehyde dehydrogenase (DHAS, EC 1.2.1.3; ABC0047 isoform) and flagellin-protein of B. clausii KSM-k16. The different expression levels of the two dehydrogenases were confirmed by quantitative RT- PCR and dehydrogenases enzymatic activity. The different patterns of protein expression can be considered as cell proteome signatures of the different strains.

The spore-bearing alkaliphilic Bacillus species constitute a large, heterogeneous group of microorganisms, important for their ability to produce enzymes, antibodies and metabolites of potential medical use. Some Bacillus species are currently being used for manufacturing probiotic products consisting of bacterial spores, exhibiting specific features (colonization, immune-stimulation and antimicrobial activity) that can account for their claimed probiotic properties. In the present work a comparative proteomic study was performed aimed at characterizing the secretome of four closely related isogenic O/C, SIN, N/R and T B. clausii strains, already marketed in a pharmaceutical mixture as probiotics.Results: Proteomic analyses revealed a high degree of concordance among the four secretomes, although some proteins exhibited considerable variations in their expression level in the four strains. Among these, some proteins with documented activity in the interaction with host cells were identified, such as the glycolytic enzyme enolase, with a putative plasminogen-binding activity, GroEL, a molecular chaperone shown to be able to bind to mucin, and flagellin protein, a structural flagella protein and a putative immunomodulation agent.Conclusion: This study shows, for the first time, differences in the secretome of the OC, SIN, NR and T B. clausii strains. These differences indicate that specific secretome features characterize each of the four strains despite their genotypic similarity. This could confer to the B. clausii strains specific probiotic functions associated with the differentially expressed proteins and indicate that they can cooperate as probiotics as the secretome components of each strain could contribute to the overall activity of a mixed probiotic preparation.

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 Lactobacillus acidophilus 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 L. acidophilus

Periodontal disease is the most frequent cause of tooth loss among adults. It is defined as a plaque-induced inflammation of the periodontal tissues that results in a loss of support of the affected teeth. This process is characterized by destruction of the periodontal attachment apparatus, increased bone resorption with loss of crestal alveolar bone, apical migration of the epithelial attachment, and formation of periodontal pockets. Although the presence of periodontal pathogens such as Porphyromonas gingivalis is a prerequisite, the progression of periodontal disease is dependent on the host response to pathogenic bacteria that colonize the tooth surface. Nowadays, a growing body of literature has accumulated to investigate the association between bone diseases, periodontal pathogens and periodontal diseases. The integration of pathogen-associated molecular patterns from microorganisms with their surface receptors in the immune cells, induces the production of several cytokines and chemokines that present either a pro- and/or anti-inflammatory role and the activation of mechanisms of controlling this and the related disease, such as osteoporosis and rheumatoid arthritis. This review focuses on the evidence and significance of bone host cell invasion by Porphyromonas gingivalis in the pathogenesis of bone disorders, as well as the different lines of evidence supporting the role of cytokines in bone diseases.

Rhinitis comprises several diseases with varying causes and different clinical manifestations and pathological features, but treated as a single clinical disorder. As heterogeneous disease, proper differential diagnosis is useful to delineate appropriate therapeutic intervention. Comparative proteomic investigation was aimed to provide information for specific differentially expressed proteins in rhino pathologic state, that could be used for diagnostic purpose and therapeutic monitoring. Methods. Proteins extracted from nasal mucosa cells of patients with different features of rhinitis and from control subjects, were separated by 2-DE. Proteins differentially expressed were identified by mass spectrometry (MS). Results. Comparative proteomic analyses led to the identification of eighteen proteins differentially expressed in patients with rhinitis, mainly related to cell defense and innate and acquired immunity. From that, at least one protein can be a possible candidate as biomarker of disease.

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.

Proteomics, the large scale study of proteins and protein variations, contributes to a better understanding of themolecular basis of variability in susceptibility to diseases that are associated with genetic diversity and environmentalfactors. The development of proteomic technologies has permitted the unprecedented large-scale identification ofproteins in any biological system. Human proteomics point out physiological conditions that could greatly impact onmedicine. This knowledge has the potential to decode the pathogenic mechanisms underlying diseases, elucidatepotential risk factors and molecular targets for drug development and therapeutic interventions and identify promisingbiomolecules that could be developed for diagnostic and prognostic purposes and for improved disease managementstrategies. 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 andproteogenomics studies are highlighted.

Lactobacilli are essential components of gut microflora and some strains exhibit probiotic features. In the gut, they participate to the metabolism of food components such as polyphenols, molecules that have well-known nutraceutical properties and positively affect microbiota composition by inhibiting pathogens and favoring probiotic growth [1].Polyphenols-microbiota interplay was investigated by proteomics using as model system the potential probiotic strain Lactobacillus acidophilus DSMZ20079 grown in presence/absence of rutin (quercetin-3-rutinoside), one of the glycosylated forms of quercetin, that is among the most studied polyphenols [2].Proteomics highlighted that molecular chaperones, Clp ATP-dependent proteases, oxidoreductases, responsible of cell redox homeostasis, and enzymes involved in energy metabolism were overexpressed in cells grown in the presence of rutin. The activation of glycolysis led to an increase of ATP production, needed to sustain ATP-dependent activity of folding and degradation machinery. Therefore, adaptation of L. acidophilus to the presence of rutin could be related to its ability to activate general stress response mechanisms.Interestingly, the activation of pyruvate kinase could parallel with the higher expression of branched-chain amino acid aminotransferase. In fact, pyruvate could be converted to ?-ketoacids and finally, by the aminotransferases action, into branched-chain amino acids, that are precursors of short chain fatty acids [3]. These molecules, produced by microbial metabolism in the gut, contribute in maintaining host homeostasis and positively act on gut inflammatory disorders. This work represents one of the first proteomic study focused on the investigation of the complex bacteria-polyphenols-interplay and further assesses the key role of proteomics in the elucidation of molecular mechanisms underlying probiotic traits.