Microbiome enrichment from contaminated marine sediments unveils novel bacterial strains for petroleum hydrocarbon and heavy metal bioremediation.

Petroleum hydrocarbons and heavy metals are some of the most widespread contaminants affecting marine ecosystems, urgently needing effective and sustainable remediation solutions. Microbial-based bioremediation is gaining increasing interest as an effective, economically and environmentally sustainable strategy. Here, we hypothesized that the heavily polluted coastal area facing the Sarno River mouth, which discharges >3 tons of polycyclic aromatic hydrocarbons (PAHs) and ∼15 tons of heavy metals (HMs) into the sea annually, hosts unique microbiomes including marine bacteria useful for PAHs and HMs bioremediation.

Antibiotic-Resistant Bacteria in Aquaculture and Climate Change: A Challenge for Health in the Mediterranean Area.

Aquaculture is the productive activity that will play a crucial role in the challenges of the millennium, such as the need for proteins that support humans and the respect for the environment. Aquaculture is an important economic activity in the Mediterranean basin. A great impact is presented, however, by aquaculture practices as they involve the use of antibiotics for treatment and prophylaxis.

Do plankton reflect the environmental quality status? The case of a post-industrial Mediterranean Bay.

While the effects of industrial contamination in coastal areas may persist for years in benthos communities, plankton should not show permanent impairments because of their high spatial dynamics, fast turnover times and pronounced seasonality. To test this hypothesis, in 2019 we conducted five surveys in the Bay of Pozzuoli (Gulf of Naples, Mediterranean Sea), in front of a dismissed steel factory and in the adjacent inshore coastal waters. High seasonal variability was observed for bacteria, phytoplankton and mesozooplankton, whereas plankton spatial gradients were relatively smooth during each survey.

Mediterranean Coastal Lagoons: The Importance of Monitoring in Sediments the Biochemical Composition of Organic Matter.

Transitional water ecosystems are targeted by the European Union (EU) Water Framework Directive (WFD, CE 2000/60) monitoring programs in coastal zones. Concerning sediments, activities performed for the WFD focus on a few variables concerning the biochemical composition of organic matter. Our research reports the effects of oxygen availability on the biochemical composition of organic matter in sediments to highlight levels of targeted variables in time and, according to the depth of sediment layer, both under oxygenated and anoxic conditions in a mesocosm study on sediment cores.

Toxicity of diatom polyunsaturated aldehydes to marine bacterial isolates reveals their mode of action.

Diatoms produce and release polyunsaturated aldehydes (PUAs) during senescence in culture and at the end of blooms in nature and these compounds play different ecological roles, as infochemicals, allelochemicals and pheromones In order to elucidate the toxic effects of PUAs, we isolated six bacterial strains from the Mediterranean Sea during a diatom bloom and tested their tolerance to PUA in terms of growth and cell membrane properties. Based upon 16S rRNA sequencing, these bacteria were assigned to the genera Pseudomonas, Sufflavibacter, Halomonas, Vibrio, Idiomarina, and Labrenzia. Growth of these strains was reduced by 50% (EC) at PUA concentrations ranging from 600 to 1700 μM of 2E,4E/Z-heptadienal (HEPTA), 400-800 μM of 2E, 4E/Z-octadienal (OCTA), and 70-400 μM of 2E, 4E/Z-decadienal (DECA).

A Bacillus sp. isolated from sediments of the Sarno River mouth, Gulf of Naples (Italy) produces a biofilm biosorbing Pb(II).

A Pb-resistant bacterial strain (named hereinafter Pb15) has been isolated from highly polluted marine sediments at the Sarno River mouth, Italy, using an enrichment culture to which Pb(II) 0.48mmoll(-1) were added. 16S rRNA gene sequencing (Sanger) allowed assignment of the isolate to the genus Bacillus, with Bacillus pumilus as the closest species.

Klebsiella sp. strain C2A isolated from olive oil mill waste is able to tolerate and degrade tannic acid in very high concentrations.

Four bacterial strains capable of growing in the presence of tannic acid as sole carbon and energy source were isolated from olive mill waste mixtures. 16S rRNA gene sequencing assigned them to the genus Klebsiella. The most efficient strain, Klebsiella sp.

Two-phase olive mill waste composting: community dynamics and functional role of the resident microbiota.

In this study, physico-chemical modifications and community dynamics and functional role of the resident microbiota during composting of humid husk from a two-phase extraction system (TPOMW) were investigated. High mineralization and humification of carbon, low loss of nitrogen and complete degradation of polyphenols led to the waste biotransformation into a high-quality compost. Viable cell counts and denaturing gradient gel electrophoresis (DGGE) profiling of the 16S rRNA genes showed that the thermophilic phase was characterized by the strongest variations of cell number, the highest biodiversity and the most variable community profiles.

Two naphthalene degrading bacteria belonging to the genera Paenibacillus and Pseudomonas isolated from a highly polluted lagoon perform different sensitivities to the organic and heavy metal contaminants.

Two bacterial strains were isolated in the presence of naphthalene as the sole carbon and energy source from sediments of the Orbetello Lagoon, Italy, which is highly contaminated with both organic compounds and metals. 16S rRNA gene sequence analysis of the two isolates assigned the strains to the genera Paenibacillus and Pseudomonas. The effect of different contaminants on the growth behaviors of the two strains was investigated.

Membrane fatty acids adaptive profile in the simultaneous presence of arsenic and toluene in Bacillus sp. ORAs2 and Pseudomonas sp. ORAs5 strains.

Bacillus sp. ORAs2 and Pseudomonas sp. ORAs5, two arsenic-resistant bacterial strains previously isolated from sediments of the Orbetello Lagoon, Italy, were tested for their adaptation to mixed contaminants on the level of membrane fatty acid composition.

Iron demand by thermophilic and mesophilic bacteria isolated from an antarctic geothermal soil.

The thermophilic bacterial strain MP 4 assigned to a new species, likely of the genus Alicyclobacillus, was isolated from geothermal soils on the NW slope of Mount Melbourne, Antarctica. These soils have high iron concentrations and the strain MP 4 requires iron additions for growth. Four mesophilic bacterial strains Paenibacillus validus MP 5, MP 8, and MP 10, and P.

An antarctic psychrotrophic bacterium Halomonas sp. ANT-3b, growing on n-hexadecane, produces a new emulsyfying glycolipid.

A bacterial strain ANT-3b was isolated at the sea-ice seawater interface from Terra Nova Bay station, Ross Sea, Antarctica. It was isolated on mineral medium supplemented with 2% diesel fuel as a sole carbon and energy source and grown routinely on 2% n-hexadecane. Analysis of 16S rRNA gene sequence indicates that the strain has 99.

Growth of Rhodosporidium toruloides strain DBVPG 6662 on dibenzothiophene crystals and orimulsion.

Strains DBVPG 6662 and DBVPG 6739 of Rhodosporidium toruloides, a basidiomycete yeast, grew on thiosulfate as a sulfur source and glucose (2 g liter(-1) or 10.75 mM) as a carbon source. DBVPG 6662 has a defective sulfate transport system, whereas DBVPG 6739 barely grew on sulfate.

Envelope glycosylation determined by lectins in microscopy sections of Acinetobacter venetianus induced by diesel fuel.

It was suggested in a previous study that cells of Acinetobacter venetianus VE-C3 adhere to diesel fuel by synthesizing a capsular polysaccharide containing glucose and/or mannose. To study the fine structure of cells and localization of bacterial polysaccharide in the presence of diesel fuel, two lectins were used: ConA, an agglutinin from Canavalia ensiformis specific for mannose and/or glucose residues, and PNA, an agglutinin from Arachis hypogaea, for terminal galactose residues. The lectins were conjugated with electron dense ferritin for transmission electron microscopy (TEM) and with fluorescein isothiocyanate (FITC) for scanning confocal laser microscopy (SCLM).

Long-term analysis of diesel fuel consumption in a co-culture of Acinetobacter venetianus, Pseudomonas putida and Alcaligenes faecalis.

The dynamics of a microbial population isolated from superficial waters of Venice Lagoon and the ability to utilise diesel fuel (n-alkanes mixture C12-C28) as the sole carbon and energy source were studied in a long-term reconstruction experiment. The reconstructed microbial population consisted of three bacterial strains belonging to the species Acinetobacter venetianus, Pseudomonas putida, and Alcaligenes faecalis, which were able to oxidise n-alkanes to alkanoates, n-alkanols to alkanoates, or only n-alkanoates, respectively. Three different approaches: plate counting, cell counting by epifluorescence microscopy with DAPI staining, and by fluorescence in situ hybridisation (FISH) by using a probe conjugate with fluoresceine isothiocyanate specifically targeted towards the 16S rRNA of bacteria belonging to the genus Acinetobacter were used to monitor the growth of the bacterial population.