Publications by authors named "Teresa L Maugeri"

Submarine hydrothermal vents are inhabited by a variety of microorganisms capable of tolerating environmental extremes, making them ideal candidates to further expand our knowledge of the limitations for terrestrial life, including their ability to survive the exposure of spaceflight-relevant conditions. The spore resistance of two Bacillus spp. strains, APA and SBP3, isolated from two shallow vents off Panarea Island (Aeolian Islands, Italy), to artificial and environmental stressors (i.

View Article and Find Full Text PDF

Herpes simplex virus type 1 (HSV-1) is responsible of common and widespread viral infections in humans through the world, and of rare, but extremely severe, clinical syndromes in the central nervous system. The emergence of resistant strains to drugs actually in use encourages the searching for novel antiviral compounds, including those of natural origin. In this study, the recently described poly-γ-glutamic acid (γ-PGA-APA), produced by the marine thermotolerant Bacillus horneckiae strain APA, and previously shown to possess biological and antiviral activity, was evaluated for its anti-HSV-1 and immunomodulatory properties.

View Article and Find Full Text PDF

The prokaryotic abundance and diversity in three cold, oligotrophic Patagonian lakes (Témpanos, Las Torres and Mercedes) in the northern region Aysén (Chile) were compared in winter and summer using 16S rRNA fluorescence in situ hybridization and PCR-denaturing gradient gel electrophoresis technique. Prokaryotic abundances, numerically dominated by Bacteria, were quite similar in the three lakes, but higher in sediments than in waters, and they were also higher in summer than in winter. The relative contribution of Archaea was greater in waters than in sediments, and in winter rather than in summer.

View Article and Find Full Text PDF

The development of antibiofilm strategies is of major interest in contrasting bacterial pathogenic biofilms. A novel fructose and fucose rich exopolysaccharide (EPS1-T14) produced by the recently described thermophilic Bacillus licheniformis T14, isolated from a shallow hydrothermal vent of Panarea Island (Eolian Island, Italy), was evaluated for its effects on biofilm formation by multiresistant clinical strains of Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Staphylococcus aureus. The antibiofilm activity of EPS1-T14 was assessed by microtiter plate assays and visualized by confocal laser scanning microscopic images.

View Article and Find Full Text PDF

Byers Peninsula (Livingston Island, Antarctica), the largest seasonally ice-free region of the Maritime Antarctica, holds a large number of lakes, ponds, and streams. The prokaryotic structure and bacterial diversity in sediment samples collected during the 2008-2009 austral summer from five inland lakes, two coastal lakes, and an estuarine site were analyzed by Catalyzed Reporter Deposition Fluorescence In Situ Hybridization (CARD-FISH) and 16S rRNA 454 tag pyrosequencing techniques, respectively. Differently from inland lakes, which range around the oligotrophic status, coastal lakes are eutrophic environments, enriched by nutrient inputs from marine animals.

View Article and Find Full Text PDF

Hot Lake is a recently described thermal brine pool off Panarea Island (Eolian Islands, Italy) where emitted fluids are highly saline and rich in CO2 and H2S. The prokaryotic community composition in surface sediment samples was analyzed by high-throughput Illumina sequencing targeting the V3 region of the 16S rRNA at two time points that differed mainly with respect to temperature conditions, high-temperature (94 °C, HT09) and low-temperature (28.5 °C, LT10).

View Article and Find Full Text PDF

Extreme marine environments, such as the submarine shallow vents of the Eolian Islands (Italy), offer an almost unexplored source of microorganisms producing unexploited and promising biomolecules for pharmaceutical applications. Thermophilic and thermotolerant bacilli isolated from Eolian vents are able to produce exopolysaccharides (EPSs) with antiviral and immunomodulatory effects against Herpes simplex virus type 2 (HSV-2). HSV-2 is responsible for the most common and continuously increasing viral infections in humans.

View Article and Find Full Text PDF

To investigate the prokaryotic community structure and composition in an active hydrothermal site, named Black Point, off Panarea Island (Eolian Islands, Italy), we examined sediment and fluid samples, differing in temperature, by a massive parallel sequencing (Illumina) technique targeting the V3 region of the 16S rRNA gene. The used technique enabled us to detect a greater prokaryotic diversity than that until now observed and to reveal also microorganisms occurring at very low abundance (≤0.01 %).

View Article and Find Full Text PDF

A haloalkaliphilic, thermophilic Bacillus strain (T14), isolated from a shallow hydrothermal vent of Panarea Island (Italy), produced a new exopolysaccharide (EPS). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain T14 was highly related (99 % similarity) to Bacillus licheniformis DSM 13(T) and Bacillus sonorensis DSM 13779(T). Further DNA-DNA hybridization analysis revealed 79.

View Article and Find Full Text PDF

The prokaryotic cells distribution in the water column of the coastal saline meromictic Lake Faro (Messina, Italy) was investigated by microscopic counting techniques. Water samples were collected at a central station from the surface to the bottom, when waters were characterized by a marked stratification. A "red-water" layer, caused by a dense growth of photosynthetic sulfur bacteria, was present at a depth of 15 m, defining a transition area between oxic (mixolimnion) and anoxic (monimolimnion) layers.

View Article and Find Full Text PDF

The variations in vertical distribution and composition of bacteria in the meromictic Lake Faro (Messina, Italy) were analysed by culture-independent methods in two different mixing conditions. Water samples were collected from a central station from the surface to the bottom (30 m depth) on two different sampling dates--the first characterised by a well-mixed water mass and the second by a marked stratification. A 'red-water' layer, caused by a dense growth of photosynthetic sulphur bacteria, was present at a depth of 25 m in December 2005 and at 15 m in August 2006, defining two different zones in terms of their physicochemical properties.

View Article and Find Full Text PDF

The immunomodulatory and antiviral effects of an extracellular polysaccharide (EPS-2), produced by a strain of Geobacillus thermodenitrificans isolated from a shallow marine vent of Vulcano Island (Italy), were evaluated. In the present study, we show for the first time that EPS-2 treatment hinder HSV-2 replication in human peripheral blood mononuclear cells (PBMC) but not in WISH cells. In fact, high levels of IFN-alpha, IL-12, IFN-gamma, TNF-alpha, IL-18 were detected in supernatants of EPS-2 treated PBMC.

View Article and Find Full Text PDF

The Alcantara River estuary was studied to obtain the first data on both water quality and ecological status of the only River Park in Sicily (Italy). Water samples were seasonally collected from three selected stations in the estuarine area and from one station at the mouth of the estuary in the marine coastal zone. Picoplankton and picophytoplankton counts were among the highest observed in estuarine environments and in other coastal waters of the Mediterranean Sea.

View Article and Find Full Text PDF

The aim of this study was to investigate the microbial community thriving at two shallow hydrothermal vents off Panarea Island (Italy). Physico-chemical characteristics of thermal waters were examined in order to establish the effect of the vents on biodiversity of both Bacteria and Archaea. Water and adjacent sediment samples were collected at different times from two vents, characterised by different depth and temperature, and analysed to evaluate total microbial abundances, sulphur-oxidising and thermophilic aerobic bacteria.

View Article and Find Full Text PDF

EPS-1 is a novel extracellular polysaccharide produced by a strain of thermotolerant Bacillus licheniformis, isolated from a shallow marine hot spring of Vulcano Island (Italy). In this paper, antiviral and immunomodulatory effects of EPS-1 were evaluated. It was found that EPS-1 treatment impaired HSV-2 replication in human peripheral blood mononuclear cells (PBMC) but not in WISH cells.

View Article and Find Full Text PDF

Vibrio vulnificus, a human and animal pathogen, is present in low numbers in the Mediterranean Sea. Seawater and plankton samples were collected from a marine coastal zone of the Straits of Messina in the Mediterranean Sea (Italy) in order to investigate V. vulnificus as free-living (>0.

View Article and Find Full Text PDF

Seawater and plankton samples from the Straits of Messina, Italy, were analysed to confirm the occurrence of potentially pathogenic Arcobacter butzleri, A. cryaerophilus and A. skirrowii.

View Article and Find Full Text PDF

Phylogenetic relationships of a thermophilic, halophilic, aerobic spore-forming strain 4-1(T), isolated from the water of a shallow sea hot spring at Vulcano Island (Italy), revealed its relatedness to members of the genus Bacillus. Chemotaxonomic and phenotypic properties of strain 4-1(T) are sufficiently different from related moderately thermophilic species, e.g.

View Article and Find Full Text PDF

During a polyphasic taxonomic analysis performed on isolates from shallow marine hydrothermal vents of Eolian Islands (Italy), three thermophilic, halotolerant bacilli, designated as strain 1bw, strain 5-2 and strain 10-1, could not be affiliated to any described species. Physiological and biochemical characteristics, membrane lipids composition, mol % G+C content, and phylogenetic relationships determined on the basis of the 16S rRNA gene sequence analysis, placed these strains within the genus Geobacillus. The three strains were only moderately related to species of Geobacillus and their relatives, members of Saccharococcus.

View Article and Find Full Text PDF