Selective herbivory of thyme chemotypes by a mollusk and a grasshopper

The common thyme (Thymus vulgaris, Labiatae) is biochemically variable, and in southern France individual plants belong to one of six chemotypes defined by the presence of specific monoterpenes. These chemotypes were exposed to herbivory by Deroceras reticulatum (Limacidae, Mollusca) and Leptophyes punctitatissimum (Tettigoniidae, Orthoptera). Members of both animal species were given the opportunity to select among all six chemotypes in individual arenas. Both species showed preferences for specific chemotypes. The chemotypes selected by Deroceras were very different from those selected by Leptophyes. Such species-specific feeding selection is found in a number of thyme herbivores, and can contribute to the maintenance of the biochemical polymorphism common to this and other species of the genus Thymus.Le thym commun (Thymus vulgaris, Labiatae) est biochimiquement variable ; en France méridionale, les individus appartiennent à l’un des six chémotypes définis par la présence de monoterpènes spécifiques. Ces chémotypes ont été soumis à la prédation de Deroceras reticulatum (Limacidae, Mollusque) et Leptophyes punctitatissimum (Tettigoniidae, Orthoptère). Des individus de ces deux espèces animales, placés dans des cages individuelles, ont eu l’opportunité de choisir parmi les six chemotypes. Les deux espèces ont montré des préférences pour des chémotypes spécifiques. Les chémotypes choisis par Deroceras étaient très différents de ceux choisis par Leptophyes. Une telle alimentation espèce-dépendante a été observée chez un certain nombre de prédateurs du thym, et peut contribuer au maintien du polymorphisme biochimique commun à cette espèce de thym et à d’autres du genre Thymus.Linhart Yan B., Chaouni-Benabdallah Loubna, Parry Jean-Marc, Thompson John D. Selective herbivory of thyme chemotypes by a mollusk and a grasshopper. In: Ecologia mediterranea, tome 25 n°2, 1999. pp. 147-151

Synthesis and characterization of zeolite HS using natural pyrophyllite as new clay source

Zeolite synthesis has been achieved by alkaline treatment of a local clay, pyrophyllite. The chemical, textural and structural characteristics of the modified clay were evaluated and compared to those of the raw clay. The samples were characterized by X-ray fluorescence, nitrogen adsorption–desorption studies, X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy and thermoanalysis (TG–DSC). The pyrophyllite was converted to porous hydroxysodalite (HS), nearly pure, which has a surface area of 19.56 m2g-1 with a spherical structure and cubic system.A. El Gaidoumi thanks Erasmus + Key Action 107 Program for his research grant in order to carry out his internship at the University of Las Palmas de Gran Canaria, Spain

Anthropogenic nitrate contamination impacts nitrous oxide emissions and microbial communities in the Marchica Lagoon (Morocco)

Lagoon systems are often confined, and their waters are poorly renewed, which makes them vulnerable to pollutants’ accumulation. Here, the impact of different sources of anthropogenic contamination (domestic, urban, industrial, and agricultural) on the nitrate (NO) content, emission of the greenhouse gas nitrous oxide (NO), abundance of total bacterial archaeal, nitrifying, and denitrifying communities, and diversity and composition of bacterial communities in the sediments of the RAMSAR-protected Marchica lagoon (Nador, Morocco) was investigated. Six lake sites differing in NO concentration were selected. Wastewater coming from industrial activities results in the greatest concentration of NO in sediments and emissions of NO. Increased carbon to nitrogen content in sites near domestic activities resulted in an increase in the abundance of total bacterial and archaeal communities, as well as nitrification and denitrification genes, but low NO emissions due to a greater presence of microorganisms involved in NO production over those able to reduce NO. Significant differences in bacterial community composition between sites were observed, with the NO content being the main driver of these changes. Increased NO content in the sampling sites significantly reduced bacterial diversity. Bacterial genera involved in the degradation of organic and inorganic pollutants and nitrous oxide reduction, such as Robiginitalea, Symbiobacterium, Bacillus, Fusibacter, Neptunomonas, Colwellia, and Alteromonas, were the most abundant in the lagoon. The results suggest that the type of anthropogenic contamination directly impacts the nitrate content in the sediments of the Marchica lagoon, which determines variations in nitrous oxide emissions, nitrogen-cycling gene abundances, and bacterial diversity

Spatio-temporal patterns of Synechococcus oligotypes in Moroccan lagoonal environments

Synechococcus are unicellular cyanobacteria susceptible to environmental fluctuations and can be used as bioindicators of eutrophication in marine ecosystems. We examined their distribution in two Moroccan lagoons, Marchica on the Mediterranean coast and Oualidia on the Atlantic, in thesummers of 2014 and 2015 using 16S rRNA amplicon oligotyping. Synechococcus representatives recruited a higher number of readsfrom the 16S rRNA in Marchica in comparison to Oualidia. We identified 31 Synechococcus oligotypes that clustered into 10 clades with different distribution patterns. The Synechococcus community was mainly represented by oligotype 1 (clade III) in Marchica. Cooccurring clades IV and I had an important relative abundance in Marchica in the summer of 2014, which is unusual, as these clades are widespread in cold waters. Moreover, Clades VII and subcluster “5.3” formed a sizeable percentage of the Synechococcus community in Marchica. Notably, we found low Synechococcus sequence counts in the Atlantic Lagoon. These results showed that the relative abundance of Synechococcusreads is not constant over space and time and that rare members of the Synechococcus community did not follow a consistent pattern. Further studies are required to decipher Synechococcus dynamics and the impact of environmental parameters on their spatial and temporal distributions.</p

Chromosomal Locus for Cadmium Resistance in Pseudomonas putida Consisting of a Cadmium-Transporting ATPase and a MerR Family Response Regulator

Pseudomonads from environmental sources vary widely in their sensitivity to cadmium, but the basis for this resistance is largely uncharactarized. A chromosomal fragment encoding cadmium resistance was cloned from Pseudomonas putida 06909, a rhizosphere bacterium, and sequence analysis revealed two divergently transcribed genes, cadA and cadR. CadA was similar to cadmium-transporting ATPases known mostly from gram-positive bacteria, and to ZntA, a lead-, zinc-, and cadmium-transporting ATPase from Escherichia coli. CadR was related to the MerR family of response regulators that normally control mercury detoxification in other bacterial systems. A related gene, zntR, regulates zntA in E. coli, but it is not contiguous with zntA in the E. coli genome as cadA and cadR were in P. putida. In addition, unlike ZntA and other CadA homologs, but similar to the predicted product of gene PA3690 in the P. aeruginosa genome, the P. putida CadA sequence had a histidine-rich N-terminal extension. CadR and the product of PA3689 of P. aeruginosa also had histidine-rich C-terminal extensions not found in other MerR family response regulators. Mutational analysis indicated that cadA and cadR are fully responsible for cadmium resistance and partially for zinc resistance. However, unlike zntA, they did not confer significant levels of lead resistance. The cadA promoter was responsive to Cd(II), Pb(II), and Zn(II), while the cadR promoter was only induced by Cd(II). CadR apparently represses its own expression at the transcriptional level. However, CadR apparently does not repress cadA. Homologs of the cadmium-transporting ATPase were detected in many other Pseudomonas species

First draft genome assembly of the Argane tree (Argania spinosa) [version 1; peer review: 1 approved, 1 approved with reservations]

Background: The Argane tree (Argania spinosa L. Skeels) is an endemic tree of southwestern Morocco that plays an important socioeconomic and ecologic role for a dense human population in an arid zone. Several studies confirmed the importance of this species as a food and feed source and as a resource for both pharmaceutical and cosmetic compounds. Unfortunately, the argane tree ecosystem is facing significant threats from environmental changes (global warming, over-population) and over-exploitation. Limited research has been conducted, however, on argane tree genetics and genomics, which hinders its conservation and genetic improvement. Methods: Here, we present a draft genome assembly of A. spinosa. A reliable reference genome of A. spinosa was created using a hybrid de novo assembly approach combining short and long sequencing reads. Results: In total, 144 Gb Illumina HiSeq reads and 7.2 Gb PacBio reads were produced and assembled. The final draft genome comprises 75 327 scaffolds totaling 671 Mb with an N50 of 49 916 kb. The draft assembly is close to the genome size estimated by k-mers distribution and covers 89% of complete and 4.3% of partial Arabidopsis orthologous groups in BUSCO. Conclusion: The A. spinosa genome will be useful for assessing biodiversity leading to efficient conservation of this endangered endemic tree. Furthermore, the genome may enable genome-assisted cultivar breeding, and provide a better understanding of important metabolic pathways and their underlying genes for both cosmetic and pharmacological purposes.This work was supported by the Iridian Genome Foundation (MD, USA). H.G. is supported by a Grant from the NIH (MD, USA) for H3ABioNet/H3Africa (grant numbers U41HG006941 and U24 HG006941). O.B. and B.C. are Fulbright JSD (USA) grant recipients. This work also benefited from support of Midterm Research Program of INRA-Morocco through the use of its bioinformatics platform

A Clinical and Molecular Genetic Study of 50 Families with Autosomal Recessive Parkinsonism Revealed Known and Novel Gene Mutations

In this study, the role of known Parkinson�s disease (PD) genes was examined in families with autosomal recessive (AR) parkinsonism to assist with the differential diagnosis of PD. Some families without mutations in known genes were also subject to whole genome sequencing with the objective to identify novel parkinsonism-related genes. Families were selected from 4000 clinical files of patients with PD or parkinsonism. AR inheritance pattern, consanguinity, and a minimum of two affected individuals per family were used as inclusion criteria. For disease gene/mutation identification, multiplex ligation-dependent probe amplification, quantitative PCR, linkage, and Sanger and whole genome sequencing assays were carried out. A total of 116 patients (50 families) were examined. Fifty-four patients (46.55; 22 families) were found to carry pathogenic mutations in known genes while a novel gene, not previously associated with parkinsonism, was found mutated in a single family (2 patients). Pathogenic mutations, including missense, nonsense, frameshift, and exon rearrangements, were found in Parkin, PINK1, DJ-1, SYNJ1, and VAC14 genes. In conclusion, variable phenotypic expressivity was seen across all families. © 2017, Springer Science+Business Media New York