Dosage des HAP dans les produits de pêche par GC-MS au niveau des côtes marocaines

Being widespread and highly likely to cause adverse biological effects, PAHs have been the subject of several studies and evaluation. Polycyclic aromatic hydrocarbons (PAHs) are a series of hydrocarbons with the carbon atoms are arranged in benzene cycles united to each other, they pose a significant toxicological risk even at low concentrations, related especially to their carcinogenic and/or mutagenic properties. In addition, PAHs are part of some biodegradable contaminants which makes them persistent in natural environments. Thus, their fate in the environment has become a concern. For humans, the majority source of exposure to PAHs for non-smokers is the ingestion of food (meat, fish, vegetables, etc.). This study is conducted on fishery products collected along the Moroccan coast, landed at the level of the main ports of the Kingdom. Analyses of mean concentrations of PAHs in local products vary significantly according to the sites (p < 0,05). The results show a satisfactory quality of these products for consumption. The sampling sites are selected so as to diagnose the state of organic contamination in various fishing products. The determination of these pollutants is done by gas chromatography coupled to mass spectrometry.Les HAP étant largement répandus et fortement susceptibles d’entraîner des effets biologiques néfastes, ils ont fait l’objet de plusieurs études et évaluations. Les Hydrocarbure Aromatique Polycyclique (HAP) sont une série d'hydrocarbures dont les atomes de carbone sont disposés en cycles benzéniques unis les uns aux autres. Ils présentent un risque toxicologique important même à de faibles concentrations, liés surtout à leurs propriétés cancérigènes et/ou mutagènes. De plus, les HAP font partie des contaminants peu biodégradables ce qui les rend persistants dans les milieux naturels. Ainsi, leur sort dans l'environnement est devenu un sujet préoccupant. Pour l'homme, la source majoritaire d'exposition aux HAP pour les non fumeurs est l'ingestion des denrées alimentaires (viandes, poissons, légumes, etc..). Cette étude est menée sur les produits de pêche prélevés le long  du littoral marocain, débarqués au niveau des principaux ports du royaume. Les analyses des teneurs moyennes des HAP dans les produits locaux variaient significativement selon les sites (p<0,05). Les résultats montrent une qualité satisfaisante de ces  produits pour la consommation. Les sites des prélèvements sont choisis de manière à diagnostiquer l’état de la contamination organique dans les différents produits pêchés. Le dosage de ces polluants est réalisé par chromatographie gazeuse couplée à la spectrométrie de masse

The ocean sampling day consortium

Ocean Sampling Day was initiated by the EU-funded Micro B3 (Marine Microbial Biodiversity, Bioinformatics, Biotechnology) project to obtain a snapshot of the marine microbial biodiversity and function of the world’s oceans. It is a simultaneous global mega-sequencing campaign aiming to generate the largest standardized microbial data set in a single day. This will be achievable only through the coordinated efforts of an Ocean Sampling Day Consortium, supportive partnerships and networks between sites. This commentary outlines the establishment, function and aims of the Consortium and describes our vision for a sustainable study of marine microbial communities and their embedded functional traits

The Ocean Sampling Day Consortium

Ocean Sampling Day was initiated by the EU-funded Micro B3 (Marine Microbial Biodiversity, Bioinformatics, Biotechnology) project to obtain a snapshot of the marine microbial biodiversity and function of the world’s oceans. It is a simultaneous global mega-sequencing campaign aiming to generate the largest standardized microbial data set in a single day. This will be achievable only through the coordinated efforts of an Ocean Sampling Day Consortium, supportive partnerships and networks between sites. This commentary outlines the establishment, function and aims of the Consortium and describes our vision for a sustainable study of marine microbial communities and their embedded functional traits

Diversity of Bradyrhizobium strains isolated from root nodules of the shrubby legume Cytisus villosus growing in the Moroccan Rif

The genotypic and phenotypic diversity of nineteen bradyrhizobial strains isolated from the root nodules of wild-grown Cytisus villosus in the central-western region of the Moroccan Rif were carried out. PCR-based RFLP (restriction fragment length polymorphism) of the 16S rDNA (ARDRA) of 19 strains using the restriction enzymes AluI, CfoI, DdeI, HinfI, MspI and RsaI showed that they grouped in 3 clusters. The cluster I includes the type strain Bradyrhizobium canariense BTA-1, the cluster II the type strain Bradyrhizobium japonicum USDA6 and the cluster III the type strains Bradyrhizobium cytisi CTAW11 and Bradyrhizobium rifense CTAW71. The results from 63 physiological and biochemical tests confirmed the existence of the B. canariense and the B. japonicum groups but also allowed the separation of the B. cytisi and B. rifense strains in two groups. The phenotypic characteristics analysed permitted description of a wide physiological and biochemical diversity among the strains, and showed that the heavy metals resistance test was the most discriminating characteristic.This study was supported by the ERDF-cofinanced grants PEAGR2012-1968 from Consejería de Economía, Innovación y Ciencia (Junta de Andalucía, Spain), and AGL2015-64582-C3-3-R from MINECO. Authors thank to AECID for the PCI-Mediterráneo grant A/017685/08 and to CNRST (Morocco) and CSIC (Spain) for cooperation grant 2009MA0013.Peer Reviewe

Characterization of Salmonella Enteritidis isolated from foods and patients in northern Morocco

OBJECTIVES: This study aimed to investigate Salmonella Enteritidis strains isolated from human and food sources in the north of Morocco by means of phenotypic and genotypic methods. METHODOLOGY: Fifteen isolates from humans and food were submitted to phage typing, XbaI-macrorestriction (pulsed field gel electrophoresis [PFGE]), enterobacterial repetitive intergenic consensus (ERIC-PCR), antimicrobial susceptibility testing, and PCR assay targeting the spvR and invA genes. RESULTS: Six fingerprinting profiles were obtained with the ERIC-PCR method, four with PFGE profiling, five with antimicrobial resistance, three with phage typing, and only one with plasmid profiling. spvR gene was detected in six strains, which did not harbour plasmids of 90 kb. CONCLUSIONS: The conclusions of this study are drawn from a limited number of isolates. It would be desirable to investigate a greater and more diverse population of Salmonella isolates. S. Enteritidis was genotyped and showed four different patterns by PFGE and six by ERIC-PCR. Accordingly, high genetic similarity and limited genetic diversity were found for these strains from north of Morocco</p

Isolation, drug resistance and molecular characterization of Salmonella isolates in northern Morocco36818

OBJECTIVES: The objective of this investigation was to assess the methods for the characterization of Salmonella isolates and to identify relationships of Salmonella isolates from human and food sources in northern Morocco. METHODOLOGY: Several Salmonella serotypes were isolated from human and food samples and were characterized using conventional culture methods, biochemical, serological, antimicrobial testing, and phage typing. Molecular analyses such as enterobacterial repetitive intergenic consensus (ERIC)-PCR, macrorestriction profiling by pulsed-field gel electrophoresis (PFGE), and virulence gene analysis were also performed. Results: Sixteen Salmonella strains were isolated in our laboratory, serotyped and identified as S. Kottbus, S. Indiana, S. London, S. Typhi, S. Hadar, S. Corvallis, S. Mbandaka, S. Ouakam, S. Tm var. cop., S. Virchow, and S. Altona. The most common resistance profiles for the isolates was ATCFATSCGKSSS, belonging to phage type PT20, ATASCSS associated with strains DT104L/ad and ATATSS for isolates that were not typeable. The PFGE patterns were different for each Salmonella serotype. All strains were negative for the virulence gene spvR. CONCLUSIONS: To our knowledge, this is the first molecular characterization of Salmonella in food and humans from Morocco. Comparison of molecular techniques for differentiating between human and food isolates of Salmonella in north of Morocco shows that ERIC typing and PFGE were more discriminating than the other techniques used in this study</p

Phosphate solubilizing and PGR activities of ericaceous shrubs microorganisms isolated from Mediterranean forest soil

Many soil microorganisms are able to transform insoluble forms of phosphorus into an accessible soluble form, thus contributing to plant nutrition through exhibiting other beneficial traits such as production of organic acids, siderophore indole acetic acid (IAA) and production of hydrogen cyanide (HCN). Achieving this purpose, ericoid fungi and actinobacteria were isolated from roots and rhizospheric soil of Calluna vulgaris L., belonging to the ericaceous family. All isolates were shown to be able to solubilize insoluble phosphate in liquid cultures and to produce transparent halos of solubilization on PVK solid medium. The actinobacteria isolate AH6 was the most efficient compared to others, producing 145.5 mg/L of phosphate and 141 mu g/L of IAA. However, fungi isolate S2 and S3 had high solubilization capacity and produced a high concentration of IAA in comparison with S1, which was a good siderophore producer. We applied a sequencing approach by amplifying the ITS region for fungi and 16S for actinobacteria. Most of the actinobacteria isolates belong to the Streptomyces genus while fungi were identified as related to ericoid mycorrhizal fungi. To evaluate the effectiveness of selected rhizobacteria and symbiotic fungi isolates and to confirm their role as biofertilizers, inoculation experimentations on plants are required

The ocean sampling day consortium

Ocean Sampling Day was initiated by the EU-funded Micro B3 (Marine Microbial Biodiversity, Bioinformatics, Biotechnology) project to obtain a snapshot of the marine microbial biodiversity and function of the world's oceans. It is a simultaneous global mega-sequencing campaign aiming to generate the largest standardized microbial data set in a single day. This will be achievable only through the coordinated efforts of an Ocean Sampling Day Consortium, supportive partnerships and networks between sites. This commentary outlines the establishment, function and aims of the Consortium and describes our vision for a sustainable study of marine microbial communities and their embedded functional traits

Nucleolin is a histone chaperone with FACT-like activity and assists remodeling of nucleosomes

Remodeling machines play an essential role in the control of gene expression, but how their activity is regulated is not known. Here we report that the nuclear protein nucleolin possesses a histone chaperone activity and that this factor greatly enhances the activity of the chromatin remodeling machineries SWI/SNF and ACF. Interestingly, nucleolin is able to induce the remodeling by SWI/SNF of macroH2A, but not of H2ABbd nucleosomes, which are otherwise resistant to remodeling. This new histone chaperone promotes the destabilization of the histone octamer, helping the dissociation of a H2A–H2B dimer, and stimulates the SWI/SNF-mediated transfer of H2A–H2B dimers. Furthermore, nucleolin facilitates transcription through the nucleosome, which is reminiscent of the activity of the FACT complex. This work defines new functions for histone chaperones in chromatin remodeling and regulation of transcription and explains how nucleolin could act on transcription