Camel Milk Resistome in Kuwait: Genotypic and Phenotypic Characterization.

Antimicrobial resistance (AMR) is one of the major global health and economic threats. There is growing concern about the emergence of AMR in food and the possibility of transmission of microorganisms possessing antibiotic resistance genes (ARGs) to the human gut microbiome. Shotgun sequencing and in vitro antimicrobial susceptibility testing were used in this study to provide a detailed characterization of the antibiotic resistance profile of bacteria and their ARGs in dromedary camel milk. Eight pooled camel milk samples, representative of multiple camels distributed in the Kuwait desert, were collected from retail stores and analyzed. The genotypic analysis showed the presence of ARGs that mediate resistance to 18 classes of antibiotics in camel milk, with the highest resistance to fluoroquinolones (12.48%) and disinfecting agents and antiseptics (9%). Furthermore, the results pointed out the possible transmission of the ARGs to other bacteria through mobile genetic elements. The in vitro antimicrobial susceptibility testing indicated that 80% of the isolates were resistant to different classes of antibiotics, with the highest resistance observed against three antibiotic classes: penicillin, tetracyclines, and carbapenems. Multidrug-resistant pathogens including Klebsiella pneumoniae, Escherichia coli, and Enterobacter hormaechei were also revealed. These findings emphasize the human health risks related to the handling and consumption of raw camel milk and highlight the necessity of improving the hygienic practices of farms and retail stores to control the prevalence of ARGs and their transmission.

The JAK-STAT Pathway as a Therapeutic Strategy in Cancer Patients with Immune Checkpoint Inhibitor-Induced Colitis: A Narrative Review.

Immunotherapy has emerged as a pivotal component in the treatment of various malignancies, encompassing lung, skin, gastrointestinal, and head and neck cancers. The foundation of this therapeutic approach lies in immune checkpoint inhibitors (ICI). While ICIs have demonstrated remarkable efficacy in impeding the neoplastic progression of these tumours, their use may give rise to substantial toxicity, notably in the gastrointestinal domain, where ICI colitis constitutes a significant aspect. The optimal positioning of Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway inhibitors in the therapeutic management of ICI colitis remains unclear. Numerous reports have highlighted notable improvements in ICI colitis through the application of pan-JAK-STAT inhibitors, with tofacitinib, in particular, reporting evident clinical remission of colitis. The precise mechanism by which JAK-STAT inhibitors may impact the pathogenetic process of ICI colitis remains inadequately understood. However, there is speculation regarding their potential role in modulating memory resident CD8+ T lymphocytes. The elucidation of this mechanism requires further extensive and robust evidence, and ongoing JAK-STAT-based trials are anticipated to contribute valuable insights.

Extracellular DNA secreted in yeast cultures is metabolism-specific and inhibits cell proliferation.

Extracellular DNA (exDNA) can be actively released by living cells and different putative functions have been attributed to it. Further, homologous exDNA has been reported to exert species-specific inhibitory effects on several organisms. Here, we demonstrate by different experimental evidence, including 1H-NMR metabolomic fingerprint, that the growth rate decline in Saccharomyces cerevisiae fed-batch cultures is determined by the accumulation of exDNA in the medium. Sequencing of such secreted exDNA represents a portion of the entire genome, showing a great similarity with extrachromosomal circular DNA (eccDNA) already reported inside yeast cells. The recovered DNA molecules were mostly single strands and specifically associated to the yeast metabolism displayed during cell growth. Flow cytometric analysis showed that the observed growth inhibition by exDNA corresponded to an arrest in the S phase of the cell cycle. These unprecedented findings open a new scenario on the functional role of exDNA produced by living cells.

Real-world clinical outcome and safety of adjuvant therapy in stage III melanoma patients: Data from two Academic Italian Institutions.

Adjuvant immunotherapy (IO) and targeted therapy (TT) have improved relapse-free survival (RFS) in patients with stage III melanoma, although about 25% of them relapse within a year. However, real-world data on treatment efficacy and safety as well as management of treatment recurrences are still limited. We retrospectively analyzed 113 patients with stage III melanoma who received at least one cycle of anti-PD-1 (nivolumab or pembrolizumab) or dabrafenib + trametinib as adjuvant therapy. Most of patients included into the analyses harbor BRAV600E mutation (66.4%) and had a stage IIIC melanoma (63.7%). Immunotherapy was administered in 48.7% of patients, whereas targeted therapy in 51.3% At data cut-off, median RFS was not reached with 12- and 24-months RFS of 81% and 64%, respectively. No new adverse events were registered. Thirty patients (26.5%) relapsed, mainly at distant sites. Patient treated with IO recurred mostly during adjuvant treatment (ON-treatment) while patients treated with TT relapsed at the end of treatment (OFF-treatment). At relapse, surgery, radiotherapy and systemic therapy were used alone or in combination. Among patients who started a first-line therapy, an excellent response switching to a different treatment was observed. Real-world outcomes and safety of adjuvant treatment for resected stage III melanoma appear comparable to clinical trials data. Moreover, management of recurrences depends on type of relapse (loco-regional vs distant) and timing (during vs OFF treatment). Furthermore, patients who relapse after adjuvant TT respond well to subsequent anti-PD1 based therapy.

Shotgun metagenomic sequencing in culture negative microbial keratitis.

PURPOSE: To evaluate the microbiota of culture negative Corneal Impression Membrane (CIM) microbial keratitis samples with the use of shotgun metagenomics analysis. METHODS: DNA of microbial keratitis samples were collected with CIM and extracted using the MasterPure™ Complete DNA and RNA Purification Kit (Epicentre). DNA was fragmented by sonication into fragments of 300 to 400 base pairs (bp) using Bioruptor® (Diagenode, Belgium) and then used as a template for library preparation. DNA libraries were sequenced on Illumina® HiSeq2500. The resulting reads were quality controlled, trimmed and mapped against the human reference genome. The unmapped reads were taxonomically classified using the Kraken software. RESULTS: 18 microbial keratitis samples were included in the study. Brevundimonas diminuta was found in 5 samples while 6 samples showed the presence of viral infections. Cutibacterium acnes, Staphylococcus aureus, Moraxella lacunata and Pseudomonas alcaligenes were also identified as the presumed putative cause of the infection in 7 samples. CONCLUSIONS: Shotgun sequencing can be used as a diagnostic tool in microbial keratitis samples. This diagnostic method expands the available tests to diagnose eye infections and could be clinically significant in culture negative samples.

Assessment of mastitis in camel using high-throughput sequencing.

Camel milk is recognized as a functional food with significant economic value. Mastitis is one of the most common and costly diseases in the dairy industry. Mastitis, which is caused by pathogens such as bacteria, viruses, fungi, and algae, has an impact on the quality and quantity of milk produced as well as animal health and welfare. There is a paucity of data on the etiological factors that cause camel mastitis. This study reports the bacterial and fungal community involved in clinical camel mastitis using Illumina amplicon sequencing. A total of 25 milk samples were analyzed, including 9 samples with mastitis and 16 healthy samples. The bacterial community in healthy samples was significantly more diverse and abundant than in mastitis samples. The fungal population in mastitis samples, on the other hand, was more diverse and abundant. As compared to healthy samples, the genera Staphylococcus, Streptococcus, Schlegelella, unclassified Enterobacteriaceae, Lactococcus, Jeotgalicoccus. and Klebsiella were found to be abundant in mastitic milk. However, the genera Corynebacterium, Enteractinococcus, unclassified Sphingomonadaceae, Atopostipes, Paenibacillus, Pseudomonas, Lactobacillus, Sphingomonas, Pediococcus and Moraxella were reduced. In the fungal community, mastitis caused a significant increase in the relative abundance of the majority of taxa, including Candida, Phanerochaete, Aspergillus, Cladosporium and unclassified Pyronemataceae, while Penicillium and Alternaria showed a decline in relative abundance. In the bacterial and fungal communities, the discriminant analysis showed 19 and 5 differently abundant genera in healthy milk and mastitic milk, respectively. In conclusion, this study showed a microbiome dysbiosis linked to clinical camel mastitis, with opportunistic pathogens outgrowing commensal bacteria that were reduced. These findings are essential in designing an appropriate control program in the camel dairy herd, as well as in preventing and treating camel mastitis.

Data on microbial diversity of camel milk microbiota determined by 16S rRNA gene sequencing.

Raw camel milk samples were collected from three geographical locations (south, north and middle Kuwait) during two seasons. Next generation sequencing of the V3-V4 regions of the 16S rRNA gene was used to analyze the bacterial community in camel milk. DNA was extracted from one hundred thirty-three samples, and libraries were prepared using custom fusion primers of the 16S rRNA gene and sequenced on Illumina HiSeq 2500 platform. 16S rRNA gene sequences were aligned against the SILVA database SSU release 138. The high-throughput sequencing data are available at the NCBI database under the Bioproject PRJNA814013. This work describes camel milk's bacterial diversity among different geographical locations and seasons. The distribution of alpha diversity measures among camel milk sample groups collected from different geographical locations and seasons is presented. A significant effect of these parameters on camel milk's bacterial diversity was shown. Linear discriminant analysis (LefSe) showed significant differentially abundant bacteria at the phylum, class, order, family and genus level among the three locations and seasons. LefSe identified a total of 83 and 40 differentially abundant genera in the different geographical locations and seasons, respectively. More details about the bacterial composition of raw camel milk at the phylum and genus level can be found in research article [1]. These data can be used to compare the diversity of milk bacterial community between different milk producing species and camels from different parts of the world. Besides, these findings will contribute to our understanding of the camel microbiome structure and might be useful for designing an appropriate control program in the camel dairy herd. The data described in this article are available in Mendeley Data [2].

The Flavone Cirsiliol from Salvia x jamensis Binds the F1 Moiety of ATP Synthase, Modulating Free Radical Production.

Several studies have shown that mammalian retinal rod outer segments (OS) are peculiar structures devoid of mitochondria, characterized by ectopic expression of the molecular machinery for oxidative phosphorylation. Such ectopic aerobic metabolism would provide the chemical energy for the phototransduction taking place in the OS. Natural polyphenols include a large variety of molecules having pleiotropic effects, ranging from anti-inflammatory to antioxidant and others. Our goal in the present study was to investigate the potential of the flavonoid cirsiliol, a trihydroxy-6,7-dimethoxyflavone extracted from Salvia x jamensis, in modulating reactive oxygen species production by the ectopic oxidative phosphorylation taking place in the OS. Our molecular docking analysis identified cirsiliol binding sites inside the F1 moiety of the nanomotor F1Fo-ATP synthase. The experimental approach was based on luminometry, spectrophotometry and cytofluorimetry to evaluate ATP synthesis, respiratory chain complex activity and H2O2 production, respectively. The results showed significant dose-dependent inhibition of ATP production by cirsiliol. Moreover, cirsiliol was effective in reducing the free radical production by the OS exposed to ambient light. We report a considerable protective effect of cirsiliol on the structural stability of rod OS, suggesting it may be considered a promising compound against oxidative stress.

Microbiome characterization of alpine water springs for human consumption reveals site- and usage-specific microbial signatures.

The microbiome of water springs is gaining increasing interest, especially in water intended for human consumption. However, the knowledge about large-scale patterns in water springs microbiome is still incomplete. The presence of bacteria in water sources used for human consumption is a major concern for health authorities; nonetheless, the standard microbiological quality checks are focused only on pathogenic species and total microbial load. Using 16S rRNA high throughput sequencing, we characterized the microbiome from 38 water springs in Trentino (Northern Italy) for 2 consecutive years in order to gain precious insights on the microbiome composition of these unexplored yet hardly exploited environments. The microbiological studies were integrated with standard measurements of physico-chemical parameters performed by the Provincial Office for Environmental Monitoring in order to highlight some of the dynamics influencing the microbial communities of these waters. We found that alpha diversity showed consistent patterns of variation overtime, and showed a strong positive correlation with the water nitrate concentration and negatively with fixed residue, electrical conductivity, and calcium concentration. Surprisingly, alpha diversity did not show any significant correlation with neither pH nor temperature. We found that despite their remarkable stability, different water springs display different coefficients of variation in alpha diversity, and that springs used for similar purposes showed similar microbiomes. Furthermore, the springs could be grouped according to the number of shared species into three major groups: low, mid, and high number of shared taxa, and those three groups of springs were consistent with the spring usage. Species belonging to the phyla Planctomycetes and Verrucomicrobia were prevalent and at relatively high abundance in springs classified as low number of shared species, whereas the phylum Lentisphaerae and the Candidate Phyla radiation were prevalent at higher abundance in the mineral and potable springs. The present study constitutes an example for standard water spring monitoring integrated with microbial community composition on a regional scale, and provides information which could be useful in the design and application of future water management policies in Trentino.

Camel milk microbiota: A culture-independent assessment.

Camel milk is renowned for its nutritional value and its therapeutic properties. It is considered a promising alternative to bovine milk due to its higher nutritional benefits, hypoallergenic characteristics and greater digestibility in the human gastrointestinal system. This study reports camel milk's bacterial and fungal microbiota, and the effect of geographical location and season on its bacterial community. We sequenced the V3-V4 regions of the16S rRNA gene for bacteria and the internal transcribed spacer (ITS) for fungi. A total of 134 samples of dromedary raw camel milk were collected from south, north and middle Kuwait during two seasons. Raw camel milk showed a diversified bacterial community, with 1196 genera belonging to 33 phyla. The four most predominant phyla of bacteria were Proteobacteria, Firmicutes, Actinobacteria and Bacteroidota. The core microbiota of raw camel milk, represented by the dominant genera shared by the majority of samples, was constituted by the genera Schlegelella, Paenibacillus, Lactobacillus, unclassified Comamonadaceae, Pediococcus, Moraxella, Acinetobacter, Staphylococcus, Enterococcus, Pseudomonas, Streptococcus, unclassified Micrococcaceae, Rothia, unclassified Sphingomonadaceae, unclassified Neisseriaceae and Sphingomonas. The fungal population was assessed in 14 raw camel milk samples, and comprised 87 genera belonging to 3 phyla. The genera Penicillium, Cladosporium, Candida, Aspergillus, Alternaria and Fusarium, dominated the fungal community. These findings shed light on raw camel milk's core bacterial and fungal microbiome. The geographical location and the season had a significant impact on the diversity and composition of camel milk microbiome.

Identification and Characterization of an RRM-Containing, RNA Binding Protein in Acinetobacter baumannii.

Acinetobacter baumannii is a Gram-negative pathogen, known to acquire resistance to antibiotics used in the clinic. The RNA-binding proteome of this bacterium is poorly characterized, in particular for what concerns the proteins containing RNA Recognition Motif (RRM). Here, we browsed the A. baumannii proteome for homologous proteins to the human HuR(ELAVL1), an RNA binding protein containing three RRMs. We identified a unique locus that we called AB-Elavl, coding for a protein with a single RRM with an average of 34% identity to the first HuR RRM. We also widen the research to the genomes of all the bacteria, finding 227 entries in 12 bacterial phyla. Notably we observed a partial evolutionary divergence between the RNP1 and RNP2 conserved regions present in the prokaryotes in comparison to the metazoan consensus sequence. We checked the expression at the transcript and protein level, cloned the gene and expressed the recombinant protein. The X-ray and NMR structural characterization of the recombinant AB-Elavl revealed that the protein maintained the typical ß1α1ß2ß3α2ß4 and three-dimensional organization of eukaryotic RRMs. The biochemical analyses showed that, although the RNP1 and RNP2 show differences, it can bind to AU-rich regions like the human HuR, but with less specificity and lower affinity. Therefore, we identified an RRM-containing RNA-binding protein actually expressed in A. baumannii.

Beneficial effect of polyphenols in COVID-19 and the ectopic F1 FO -ATP synthase: Is there a link?

COVID-19 has been proposed to be an endothelial disease, as endothelial damage and oxidative stress contribute to its systemic inflammatory and thrombotic events. Polyphenols, natural antioxidant compounds appear as promising agents to prevent and treat COVID-19. Polyphenols bind and inhibit the F1 Fo -ATP synthase rotary catalysis. An early target of polyphenols may be the ectopic F1 Fo -ATP synthase expressed on the endothelial plasma membrane. Among the pleiotropic beneficial action of polyphenols in COVID-19, modulation of the ecto-F1 Fo -ATP synthase, lowering the oxidative stress produced by the electron transfer chain coupled to it, would not be negligible.

Evolutionary Adaptation of the Thyroid Hormone Signaling Toolkit in Chordates.

The specification of the endostyle in non-vertebrate chordates and of the thyroid gland in vertebrates are fundamental steps in the evolution of the thyroid hormone (TH) signaling to coordinate development and body physiology in response to a range of environmental signals. The physiology and biology of TH signaling in vertebrates have been studied in the past, but a complete understanding of such a complex system is still lacking. Non-model species from non-vertebrate chordates may greatly improve our understanding of the evolution of this complex endocrine pathway. Adaptation of already existing proteins in order to perform new roles is a common feature observed during the course of evolution. Through sequence similarity approaches, we investigated the presence of bona fide thyroid peroxidase (TPO), iodothyronine deiodinase (DIO), and thyroid hormone receptors (THRs) in non-vertebrate and vertebrate chordates. Additionally, we determined both the conservation and divergence degrees of functional domains at the protein level. This study supports the hypothesis that non-vertebrate chordates have a functional thyroid hormone signaling system and provides additional information about its possible evolutionary adaptation.

Mesorhizobium comanense sp. nov., isolated from groundwater.

Strain 3P27G6T was isolated from an artesian well connected to the thermal water basin of Comano Terme, Province of Trento, Italy. In phylogenetic analyses based on multilocus sequence analysis, strain 3P27G6T clustered together with Mesorhizobium australicum WSM2073T. Genome sequencing produced a 99.51 % complete genome, with a length of 7 363 057 bp and G+C content of 63.53 mol%, containing 6897 coding sequences, 55 tRNA and three rRNA. Average nucleotide identity analysis revealed that all distances calculated between strain 3P27G6T and the other Mesorhizobium genomes were below 0.9, indicating that strain 3P27G6T represents a new species. Therefore, we propose the name Mesorhizobium comanense sp. nov. with the type strain 3P27G6T (=DSM 110654T=CECT 30067T). Strain 3P27G6T is a Gram-negative, rod-shaped, aerobic bacterium. Growth condition, antibiotic susceptibility, metabolic and fatty acid-methyl esters profiles of the strain were determined. Only few nodulation and nitrogen fixation genes were found in the genome, suggesting that this strain may not be specialized in nodulation or in nitrogen fixation.

Arabidopsis thaliana Response to Extracellular DNA: Self Versus Nonself Exposure.

The inhibitory effect of extracellular DNA (exDNA) on the growth of conspecific individuals was demonstrated in different kingdoms. In plants, the inhibition has been observed on root growth and seed germination, demonstrating its role in plant-soil negative feedback. Several hypotheses have been proposed to explain the early response to exDNA and the inhibitory effect of conspecific exDNA. We here contribute with a whole-plant transcriptome profiling in the model species Arabidopsis thaliana exposed to extracellular self- (conspecific) and nonself- (heterologous) DNA. The results highlight that cells distinguish self- from nonself-DNA. Moreover, confocal microscopy analyses reveal that nonself-DNA enters root tissues and cells, while self-DNA remains outside. Specifically, exposure to self-DNA limits cell permeability, affecting chloroplast functioning and reactive oxygen species (ROS) production, eventually causing cell cycle arrest, consistently with macroscopic observations of root apex necrosis, increased root hair density and leaf chlorosis. In contrast, nonself-DNA enters the cells triggering the activation of a hypersensitive response and evolving into systemic acquired resistance. Complex and different cascades of events emerge from exposure to extracellular self- or nonself-DNA and are discussed in the context of Damage- and Pathogen-Associated Molecular Patterns (DAMP and PAMP, respectively) responses.

The rice foot rot pathogen Dickeya zeae alters the in-field plant microbiome.

Studies on bacterial plant diseases have thus far been focused on the single bacterial species causing the disease, with very little attention given to the many other microorganisms present in the microbiome. This study intends to use pathobiome analysis of the rice foot rot disease, caused by Dickeya zeae, as a case study to investigate the effects of this bacterial pathogen to the total resident microbiome and to highlight possible interactions between the pathogen and the members of the community involved in the disease process. The microbiome of asymptomatic and the pathobiome of foot-rot symptomatic field-grown rice plants over two growing periods and belonging to two rice cultivars were determined via 16S rRNA gene amplicon sequencing. Results showed that the presence of D. zeae is associated with an alteration of the resident bacterial community in terms of species composition, abundance and richness, leading to the formation of microbial consortia linked to the disease state. Several bacterial species were significantly co-presented with the pathogen in the two growing periods suggesting that they could be involved in the disease process. Besides, culture-dependent isolation and in planta inoculation studies of a bacterial member of the pathobiome, identified as positive correlated with the pathogen in our in silico analysis, indicated that it benefits from the presence of D. zeae. A similar microbiome/pathobiome experiment was also performed in a symptomatically different rice disease evidencing that not all plant diseases have the same consequence/relationship with the plant microbiome. This study moves away from a pathogen-focused stance and goes towards a more ecological perception considering the effect of the entire microbial community which could be involved in the pathogenesis, persistence, transmission and evolution of plant pathogens.

The diterpene Manool extracted from Salvia tingitana lowers free radical production in retinal rod outer segments by inhibiting the extramitochondrial F1 Fo ATP synthase.

Uncontrolled oxidative stress production, especially in the outer retina is one of the causes of retinal degenerations. Mitochondria are considered the principal source of oxidative stress. However, a Reactive Oxygen Intermediates (ROI) production in the retinal photoreceptor layer seems to depend also on the expression of an extramitochondrial oxidative phosphorylation (OxPhos) machinery in the rod outer segments (OS). In fact, OS conduct aerobic metabolism, producing ATP through oxygen consumption, although it is devoid of mitochondria. As diterpenes display an antioxidant effect, we have evaluated the effect Manool, extracted from Salvia tingitana, on the extramitochondrial OxPhos and the ROI production in the retinal rod OS. Results confirm that the OxPhos machinery is ectopically expressed in the OS and that F1 Fo -ATP synthase is a target of Manool, which inhibited the OS ATP synthesis, binding the F1 moiety with high affinity, as analysed by molecular docking. Moreover, the overall slowdown of OxPhos metabolism reduced the ROI production elicited in the OS by light exposure, in vitro. In conclusion, data are consistent with the antioxidant properties of Salvia spp., suggesting its ability to lower oxidative stress production, a primary risk factor for degenerative retinal diseases. SIGNIFICANCE OF THE STUDY: Here we show that Manool, a diterpene extracted from Salvia tingitana has the potential to lower the free radical production by light-exposed rod outer segments in vitro, by specifically targeting the rod OS F1 Fo -ATP synthase belonging to the extramitochondrial OxPhos expressed on the disk membrane. The chosen experimental model allowed to show that the rod OS is a primary producer of oxidative stress linked to the pathogenesis of degenerative retinal diseases. Data are also consistent with the antioxidant and anti-inflammatory action of Salvia spp., suggesting a beneficial effect also in vivo.

Essential Oils as Alternative Biocides for the Preservation of Waterlogged Archaeological Wood.

Waterlogged archaeological wood is exposed to a high risk of biological degradation during the post-excavation phases of storage and restoration. For this reason, often biocides must be used to preserve wooden remains. In the present work three essential oils (cinnamon, wild thyme, and common thyme) were tested as possible alternative biocides to use in the preservation of waterlogged archaeological wood. The oils were first tested in vitro to establish the minimum inhibitory concentration (MIC) and to evaluate the biocidal activity on selected fungal strains. Then, the established MIC was applied on waterlogged archaeological wood samples and during an actual restoration treatment. The effectiveness of the oils was evaluated through cultural analyses, ATP quantification, and next-generation sequencing. The results showed that the oils caused a significant decrease in the vitality of fungal mycelia grown in vitro and of the microbiota present in treated wood and storage water. Furthermore, an influence on the composition of the bacterial communities of treated wood samples was observed. Although further tests are needed to evaluate interferences with the materials used during restoration procedures, essential oils could be considered as a possible alternative to the currently used biocide.

Sclareol modulates free radical production in the retinal rod outer segment by inhibiting the ectopic f1fo-atp synthase.

We have previously shown that the retinal rod outer segments (OS) produce reactive oxygen species in the function of illumination in vitro, establishing a relationship among the extra-mitochondrial oxidative phosphorylation and phototransduction. This source of oxidative stress in the OS can be modulated by polyphenols, acting as inhibitors of F1Fo-ATP synthase. The present study aimed at exploring whether sclareol, a diterpene, interacts with F1Fo-ATP synthase mitigating the light-induced free radical production in the rod OS. Characterization of bovine retinal sections was conducted by immunogold analysis. Reactive oxygen intermediates production, oxygen consumption, the activity of the four respiratory complexes and ATP synthesis were evaluated in purified bovine rod OS. Molecular docking analyses were also conducted. Sclareol reduced free radical production by light-exposed rod OS. Such antioxidant effect was associated with an inhibition of the respiratory complexes and oxygen consumption (OCR), in coupled conditions. Sclareol also inhibited the rod OS ATP synthetic ability. Since the inhibitor effect on respiratory complexes and OCR is not observed in uncoupled conditions, it is supposed that the modulating effect of sclareol on the ectopic oxidative phosphorylation in the rod OS targets specifically the F1Fo-ATP synthase. This hypothesis is confirmed by the in silico molecular docking analyses, which shows that sclareol binds the F1 moiety of ATP synthase with high affinity. In conclusion, a beneficial effect of sclareol can be envisaged as a modulator of oxidative stress in the photoreceptor, a risk factor for the degenerative retinal diseases, suggestive of its potential beneficial action also in vivo.

Characterization of black patina from the Tiber River embankments using Next-Generation Sequencing.

Black patinas are very common biological deterioration phenomena on lapideous artworks in outdoor environments. These substrates, exposed to sunlight, and atmospheric and environmental agents (i.e. wind and temperature changes), represent extreme environments that can only be colonized by highly versatile and adaptable microorganisms. Black patinas comprise a wide variety of microorganisms, but the morphological plasticity of most of these microorganisms hinders their identification by optical microscopy. This study used Next-Generation Sequencing (NGS) (including shotgun and amplicon sequencing) to characterize the black patina of the travertine embankments (muraglioni) of the Tiber River in Rome (Italy). Overall, the sequencing highlighted the rich diversity of bacterial and fungal communities and allowed the identification of more than one hundred taxa. NGS confirmed the relevance of coccoid and filamentous cyanobacteria observed by optical microscopy and revealed an informative landscape of the fungal community underlining the presence of microcolonial fungi and phylloplane yeasts. For the first time high-throughput sequencing allowed the exploration of the expansive diversity of bacteria in black patina, which has so far been overlooked in routine analyses. Furthermore, the identification of euendolithic microorganisms and weathering agents underlines the biodegradative role of black patina, which has often been underestimated. Therefore, the use of NGS to characterize black patinas could be useful in choosing appropriate conservation treatments and in the monitoring of stone colonization after the restoration interventions.