Elisa Garuglieri | King Abdullah University of Science and Technology (KAUST) (original) (raw)

Papers by Elisa Garuglieri

Microbiome

Background The transition from water to air is a key event in the evolution of many marine organi... more Background The transition from water to air is a key event in the evolution of many marine organisms to access new food sources, escape water hypoxia, and exploit the higher and temperature-independent oxygen concentration of air. Despite the importance of microorganisms in host adaptation, their contribution to overcoming the challenges posed by the lifestyle changes from water to land is not well understood. To address this, we examined how microbial association with a key multifunctional organ, the gill, is involved in the intertidal adaptation of fiddler crabs, a dual-breathing organism. Results Electron microscopy revealed a rod-shaped bacterial layer tightly connected to the gill lamellae of the five crab species sampled across a latitudinal gradient from the central Red Sea to the southern Indian Ocean. The gill bacterial community diversity assessed with 16S rRNA gene amplicon sequencing was consistently low across crab species, and the same actinobacterial group, namely Ilu...

Microbiology Spectrum

Bioturbation is one of the most important processes that governs sediment biocenosis in intertida... more Bioturbation is one of the most important processes that governs sediment biocenosis in intertidal systems. By facilitating oxygen penetration into anoxic layers, bioturbation alters the overall sediment biogeochemistry.

PLOS ONE

Due to the chemico-physical differences between air and water, the transition from aquatic life t... more Due to the chemico-physical differences between air and water, the transition from aquatic life to the land poses several challenges for animal evolution, necessitating morphological, physiological and behavioural adaptations. Microbial symbiosis is known to have played an important role in eukaryote evolution, favouring host adaptation under changing environmental conditions. We selected mangrove brachyuran crabs as a model group to investigate the prokaryotes associated with the gill of crabs dwelling at different tidal levels (subtidal, intertidal and supratidal). In these animals, the gill undergoes a high selective pressure, finely regulating multiple physiological functions during both animal submersion under and emersion from the periodical tidal events. We hypothesize that similarly to other marine animals, the gills of tidal crabs are consistently colonized by prokaryotes that may quantitatively change along the environmental gradient driven by the tides. Using electron mic...

&lt;p&gt;Stromatolites are the vestige of first life on earth and were the domina... more &lt;p&gt;Stromatolites are the vestige of first life on earth and were the dominating carbonate forming marine biota in the Archean and Proterozoic.&amp;#160; During the course of the Phanerozoic their importance in producing carbonates has been reduced to niche occurrences usually found in challenging environments, such as hypersaline marine settings and alkaline lakes.&amp;#160; Most recently, the discovery in 2010 of a new chlorophyll type - chlorophyll f - from stromatolites in Hamelin Pool in Shark Bay, Western Australia has sparked much additional interest in the genesis and composition of modern stromatolites. &amp;#160;&lt;/p&gt;&lt;p&gt;We report the discovery of stromatolites in the NE Red Sea on Sheybara Island, Al Wajh carbonate platform, KSA.&amp;#160; Based on satellite and drone surveys calibrated by site surveys, the Red Sea stromatolites are distributed over an area of about 50,000 m&lt;sup&gt;2&lt;/sup&gt; in an intertidal to very shallow subtidal setting on a paleo-reef flat facing the open sea.&amp;#160; Two principal growth shapes are recognized: (i) elongated rhomboidal structures 10-100 cm in length, up to 5-50 cm in width and up to 10 cm in height and (ii) low relief (height &lt;3 cm) irregular shaped tabular sheets in the shallow subtidal environment.&amp;#160; The rhomboidal intertidal stromatolites are pustular on the outside and laminated internally. X-ray CT scanning of the stromatolite samples showed moderately well laminated, millimeter scale, lithified layers potentially representing alternating modes of sedimentation and growth. Scanning Electron Microscopy (SEM) revealed that laminae consist of heavily bored carbonate grains, calcified tubes of filamentous cyanobacteria, mucoid sheets and spider-web like organic matter of likely dehydrated extracellular polymeric substance (EPS).&amp;#160; Carbonate precipitates of sub-micron size equant crystals and elongated aragonite needles, either occurring as single rods or in mashes, were also apparent from SEM. Molecular analysis of bacteria diversity show that cyanobacteria dominate the stromatolite surface, while heterotrophic bacteria are the main component in deeper layers.&lt;/p&gt;&lt;p&gt;During a sampling campaign in March 2021 salinity, pH and dissolved oxygen have been measured with average values at 42ppt, 7.8&amp;#177;0.1 and 5.9&amp;#177;0.5mg/L, respectively, typical for coastal Red Sea surface marine waters.&amp;#160; Water temperatures range from 18&amp;#176;C in the winter to 29&amp;#176;C in the summer.&amp;#160; During exposure at low tides surface temperatures over the tidal flats may fall as low as 12&amp;#176;C in the winter exceeding 43&amp;#176;C in the summer.&amp;#160; Large numbers of cerithid gastropods were found grazing on the stromatolite surfaces apparently not affecting their growth.&lt;/p&gt;&lt;p&gt;Hence, the setting and conditions are overall similar to some of the stromatolites found on the Exuma Islands in the Bahamas, the only other known occurrence of stromatolites in normal marine waters.&amp;#160; Research is continuing on the environmental conditions, the aerial distribution, the microbial diversity and chemical composition of these modern stromatolites to determine why they form in this particular location and if they are similar or not to other reported occurrences of stromatolites.&lt;/p&gt;

Frontiers in Microbiology, 2021

Academic year: 2016/2017 "E per il resto lasciatevi accadere la vita. Credetemi: la vita ha ragio... more Academic year: 2016/2017 "E per il resto lasciatevi accadere la vita. Credetemi: la vita ha ragione, in tutti i casi. Non vi osservate troppo. Non ricavate conclusioni troppo rapide da quello che vi accade; lasciate che semplicemente vi accada.

Frontiers in Microbiology, 2019

Environmental Pollution, 2019

RUNNING TITLE Impact of silver nanoparticles on gut microbiota HIGHLIGHTS • Interactions among Ag... more RUNNING TITLE Impact of silver nanoparticles on gut microbiota HIGHLIGHTS • Interactions among AgNPs, the intestinal microbiota, and a probiotic were tested • AgNPs did not affect the core fecal microflora and its metabolic and toxic profiles • Functional differences in few critical pathways occurred in AgNPs-treated samples • The probiotic had a chemopreventive role on fecal microflora against AgNPs CAPSULE This work will contribute to better understand the effects of non-lethal concentrations of AgNPs on the gut microbiota, and their interactions with probiotic administrations.

The ever-growing exploitation of nanotechnologies and innovative nanomaterials in food and agricu... more The ever-growing exploitation of nanotechnologies and innovative nanomaterials in food and agricultural applications is rising a number of safety, environmental, ethical, policy and regulatory issues, becoming a priority field for scientific research. At present, packaging is the major foodrelated area of nanoparticles\u2019 application (NPs, particles between 1 and 100 nanometers in size), increasing human oral exposure to estimated consumes of over a trillion man-made food-related NPs every day per person in developed countries. In addition, the growing awareness of the importance of the gut microbiome in health and disease, and the recognition that intestinal microflora exists as a biofilm with characteristics different from its planktonic counterpart, highlights the need to consider how deeply microbial and in particular bioflm-structures ecology can affect human health. However, a little number of published studies considered both the complexity of anaerobic intestinal biofilms and their interactions with food-related NPs and literature on the safety of oral exposure to food-related NPs and their effects on human-relevant biological systems provides insufficient reliable data. The NanoGut project funded by Fondazione Cariplo aims to elucidate the effects of sub-lethal concentrations of food-related NPs on the gut interactive ecosystem, potential toxicity mechanisms, and create the scientific know-how to develop leading edge methodologies vital for the nanosafety assessment. NanoGut involves the development of an interactive in vitro gut ecosystem model composed by: 1) Caco-2 intestinal epithelial cell; 2) anaerobic mono- and multi-species intestinal biofilm; 3) silver nanoparticles (AgNPs), chosen as the more representative engineered nanoparticles used in food packages and conservation, will be used as related-food NPs models; 4) a probiotic bacterium (Bacillus subtilis natto)

Ingestion of silver nanoparticles (AgNPs) is inevitable linked to their widespread use in food, m... more Ingestion of silver nanoparticles (AgNPs) is inevitable linked to their widespread use in food, medicines and other consumer products. However, their effects on human microbiota at non-lethal concentrations remain poorly understood. In this study, the interactions among 1 mg mL 1 AgNPs, the intestinal microbiota, and the probiotic Bacillus subtilis (BS) were tested using in-vitro batch fermentation models inoculated with human fecal matter. Results from metagenomic investigations revealed that the core bacterial community was not affected by the exposure of AgNPs and BS at the later stage of fermentation, while the proportions of rare species changed drastically with the treatments. Furthermore, shifts in the Firmicutes/Bacteriodetes (F/B) ratios were observed after 24 h with an increase in the relative abundance of Firmicutes species and a decrease in Bacteroidetes in all fermentation cultures. The co-exposure to AgNPs and BS led to the lowest F/B ratio. Fluorescent in-situ hybridization analyses indicated that non-lethal concentration of AgNPs negatively affected the relative percentage of Faecalibacterium prausnitzii and Clostridium coccoides/Eubacterium rectales taxa in the fermentation cultures after 24 h. However, exposure to single and combined treatments of AgNPs and BS did not change the overall diversity of the fecal microflora. Functional differences in cell motility, translation, transport, and xenobiotics degradation occurred in AgNPs-treated fermentation cultures but not in AgNPsþBS-treated samples. Compared to the control samples, treated fecal cultures showed no significant statistical differences in terms of short-chain fatty acids profiles, cytotoxic and genotoxic effects on Caco-2 cell monolayers. Overall, AgNPs did not affect the composition and diversity of the core fecal microflora and its metabolic and toxic profiles. This work indicated a chemopreventive role of probiotic on fecal microflora against AgNPs, which were shown by the decrease of F/B ratio and the unaltered state of some key metabolic pathways.

Sviluppo di un approccio innovativo, sia concettuale che operativo, in grado di coniugare, senza ... more Sviluppo di un approccio innovativo, sia concettuale che operativo, in grado di coniugare, senza sovrapporle in maniera vincolante, la dimensione artistica e quella di ricerca scientifica.
Se da un lato l’apporto innovativo rispetto al mondo delle installazioni di arte interattiva consiste proprio nel dualismo installazione-strumento di indagine scientifica, dall’altro la progettazione e lo sviluppo del prototipo è imprescindibile, assieme allo studio rigoroso del concept, da una certa coerenza con le esigenze della futura ricerca di modo che essa possa risultare attendibile e pionieristica. Nello specifico ci si propone di stimolare, attraverso l’uso di oggetti interattivi (suoni e immagini rilassanti), uno stato di rilassatezza e focalizzazione dell’attenzione cosciente che permetta alle istanze inconsce di emergere ed interagire con il sistema randomico il quale, infine, restituirà non un valore quantitativo ma un responso con significato simbolico.
La novità che questo approccio apporta alle precedenti esperienze di mPK presenti in letteratura è proprio questa: non si intende analizzare le semplici anomalie di frequenza REG (già dimostrate dal PEAR project di Princeton), ma valutare la ricorrenza di correlazioni di tipo simbolico quali esito dell’interazione tra l’individuo e il sistema randomico. Questo permetterebbe di “chiudere il cerchio” delle esperienze scientifiche circa la sincronicità approfondendone la seconda condizione così come definita da Jung e Pauli tramite l’acquisizione di dati su quella parte del fenomeno che risulta più misteriosa, intima e soggettiva.

Frontiers in Microbiology, 2018

Nanotechnology applications are expected to bring a range of benefits to the food sector, aiming ... more Nanotechnology applications are expected to bring a range of benefits to the food sector, aiming to provide better quality and conservation. In this research, the physiological response of both an Escherichia coli mono-species biofilm and Caco-2 intestinal cells to sub-lethal concentrations of silver nanoparticles (AgNPs) has been investigated. In order to simulate the anaerobic and aerobic compartments required for bacteria and intestinal cells growth, a simplified semi-batch model based on a transwell permeable support was developed. Interaction between the two compartments was obtained by exposing Caco-2 intestinal cells to the metabolites secreted by E. coli biofilm after its exposure to AgNPs. To the best of the authors’ knowledge, this study is the first to investigate the effect of AgNPs on Caco-2 cells that takes into consideration previous AgNP-intestinal biofilm interactions, and at concentrations mimicking real human exposure. Our data show that 1 μg/mL AgNPs in anaerobic conditions (i) promote biofilm formation up to 2.3 ± 0.3 fold in the first 72 h of treatment; (ii) increase reactive oxygen species (ROS) production to 84 ± 21% and change the physiological status of microbial cells after 96 h of treatment; (iii) seriously affect a 72-h old established biofilm, increasing the level of oxidative stress to 86 ± 21%. Moreover, the results indicate that oxygen renders the biofilm more adequate to counteract AgNP effects. Comet assays on Caco-2 cells demonstrated a protective role of biofilm against the genotoxic effect of 1 μg/mL AgNPs on intestinal epithelial cells.

Biointerphases, Jan 16, 2016

The present work is aimed at comparing the effects of sublethal concentrations of silver nanopart... more The present work is aimed at comparing the effects of sublethal concentrations of silver nanoparticles (AgNPs) on the growth kinetic, adhesion ability, oxidative stress, and phenotypic changes of model bacteria (Escherichia coli and Bacillus subtilis) under both aerobic and anaerobic conditions. Growth kinetic tests conducted in 96-well microtiter plates revealed that sublethal concentrations of AgNPs do not affect E. coli growth, whereas 1 μg/ml AgNPs increased B. subtilis growth rate under aerobic conditions. At the same concentration, AgNPs promoted B. subtilis adhesion, while it discouraged E. coli attachment to the surface in the presence of oxygen. As determined by 2,7-dichlorofluorescein-diacetate assays, AgNPs increased the formation of intracellular reactive oxygen species, but not at the highest concentrations, suggesting the activation of scavenging systems. Finally, motility assays revealed that 0.01 and 1 μg/ml AgNPs, respectively, promoted surface movement in E. coli a...

CV by Elisa Garuglieri