Elucidating metabolic pathways through genomic analysis in highly heavy metal-resistant strains.

The annotated and predicted genomes of five archaeal strains (AS1, AS2, AS8, AS11 and AS19), isolated from Sfax solar saltern sediments (Tunisia) and affiliated with , were performed by RAST webserver (Rapid Annotation using Subsystem Technology) and NCBI prokaryotic genome annotation pipeline (PGAP). The results showed the ability of strains to use a reduced semi-phosphorylative Entner-Doudoroff pathway for glucose degradation and an Embden-Meyerhof one for gluconeogenesis. They could use glucose, fructose, glycerol, and acetate as sole source of carbon and energy.

Influence of localized sources and meteorological conditions on dry-deposited particles: A case study of Gabès, Tunisia.

This study investigates the spatial and temporal variations of dry-deposited particles on the surface (by turbulence or gravity) in various sites within Gabès city and its surroundings, South-eastern Tunisia. Monthly samples were collected from five distinct locations: suburban-industrial (S2), suburban-residential (S3), and urban sites (S1, S4, and S5). The average monthly particle deposition flows ranged from 7.

Extreme halophilic : carotenoids characterization and antioxidant properties.

Important marine microorganisms are resources of renewable energy that may face global population growth and needs. The application of biomass metabolites, such as carotenoids and their derivatives, may solve some agro-food health problems. Herein, a new halophilic producing carotenoid was screened from a Tunisian solar Saltworks (Sfax).

Hydrolytic enzyme screening and carotenoid production evaluation of halophilic archaea isolated from highly heavy metal-enriched solar saltern sediments.

This paper aimed to screen the enzymatic activities and evaluate the carotenoid production level of twenty-two halophilic archaea isolated from Sfax solar saltern sediments. The molecular identification performed by sequencing the 16S rRNA genes showed that all strains have a high similarity degree (99.7-100%) with Halobacterium salinarum NRC-1.

Genomic analysis of heavy metal-resistant Halobacterium salinarum isolated from Sfax solar saltern sediments.

The draft genome sequences of five archaeal strains, isolated from Sfax solar saltern sediments and affiliated with Halobacterium salinarum, were analyzed in order to reveal their adaptive strategies to live in hypersaline environments polluted with heavy metals. The genomes of the strains (named AS1, AS2, AS8, AS11, and AS19) are found to contain 2,060,688; 2,467,461; 2,236,624; 2,432,692; and 2,428,727 bp respectively, with a G + C content of 65.5, 66.

Resistance of a Halobacterium salinarum isolate from a solar saltern to cadmium, lead, nickel, zinc, and copper.

The current study focuses on the tolerance of a strain of Halobacterium salinarum isolated from Sfax solar saltern (Tunisia) towards cadmium (Cd), lead (Pb), nickel (Ni), zinc (Zn), and copper (Cu) by using agar dilution methods in complex and minimal media. The results showed the least inhibitory metals based on Minimum Inhibitory Concentrations (MICs) were lead (MIC = 4.5 mM), cadmium (MIC = 4 mM), and nickel (MIC = 2.

Biological properties of carotenoids extracted from Halobacterium halobium isolated from a Tunisian solar saltern.

Background: Bioactive molecules have received increasing attention due to their nutraceutical attributes and anticancer, antioxidant, antiproliferative and apoptosis-inducing properties. This study aimed to investigate the biological properties of carotenoids extracted from Archaea.

Methods: Halophilic Archaea strains were isolated from the brine of a local crystallizer pond (TS7) of a solar saltern at Sfax, Tunisia.

Molecular community analysis of magnesium-rich bittern brine recovered from a Tunisian solar saltern.

The microbial community of a magnesium-rich bittern brine saturated with NaCl (380-400 g/L) from a Tunisian solar saltern was investigated using a molecular approach based on 16S rRNA gene analysis and viability tests. The results revealed the existence of microbial flora. Viability test assessment showed that 46.

Assessment of sediment quality in the Mediterranean Sea-Boughrara lagoon exchange areas (southeastern Tunisia): GIS approach-based chemometric methods.

Concentrations of selected heavy metals (Cd, Pb, Zn, Cu, Mn, and Fe) in surface sediments from 66 sites in both northern and eastern Mediterranean Sea-Boughrara lagoon exchange areas (southeastern Tunisia) were studied in order to understand current metal contamination due to the urbanization and economic development of nearby several coastal regions of the Gulf of Gabès. Multiple approaches were applied for the sediment quality assessment. These approaches were based on GIS coupled with chemometric methods (enrichment factors, geoaccumulation index, principal component analysis, and cluster analysis).

Novel prokaryotic diversity in sediments of Tunisian multipond solar saltern.

The phylogenetic diversity of a sediment microbial community from two ponds having different salinities, 150-200 g/l (M2) and 250-300 g/l (TS38), of an Sfax (Tunisia) solar saltern, was investigated using 16S rRNA clone libraries. The 16S rRNA genes from 135 bacterial clones and 105 archaeal clones were sequenced and phylogenetically analyzed. 32 operational taxonomic units (OTUs) were generated for Bacteria and 64 for Archaea.

Microbial community of salt crystals processed from Mediterranean seawater based on 16S rRNA analysis.

Phylogenetic analysis of 16S rRNA was used to investigate for the first time the structure of the microbial community that inhabits salt crystals retrieved from the bottom of a solar saltern, located in the coastal area of the Mediterranean Sea (Sfax, Tunisia). This community lives in an extremely salty environment of 250-310 g/L total dissolved salt. A total of 78 bacterial 16S rRNA clone sequences making up to 21 operational taxonomic units (OTUs), determined by the DOTUR program to 97% sequence similarity, was analyzed.

Isolation and characterization of moderately halophilic bacteria from Tunisian solar saltern.

Bacterial screenings from solar saltern in Sfax (Tunisia) lead to the isolation of 40 moderately halophilic bacteria which were able to grow optimally in media with 5-15% of salt. These isolates were phylogenetically characterized using 16S rRNA gene sequencing. Two groups were identified including 36 strains of Gamma-Proteobacteria (90%) and 4 strains of Firmicutes (10%).

Prokaryotic diversity of a Tunisian multipond solar saltern.

16S rRNA gene clone libraries were separately constructed from three ponds with different salt concentrations, M2 (15%), TS38 (25%) and S5 (32%), located within a multipond solar saltern of Sfax. The 16S rRNA genes from 216 bacterial clones and 156 archaeal clones were sequenced and phylogenetically analyzed. 44 operational taxonomic units (OTUs) were generated for Bacteria and 67 for Archaea.