Root system response in Argania spinosa plants under drought stress and recovery.

The argane tree is a remarkable essence by its botanical interest and its socioeconomic value. It is endemic species in the southwest of Morocco, where prolonged drought stress may occur. Although its tolerance has been commonly attributed to various mechanisms at the whole plant, the root system has a main role in the whole process of adaptation. We studied in argane tree plants the change in hydraulic conductivity, electrolyte leakage in root as well as root growth under drought stress and recovery. Our findings showed that the root hydraulic conductivity (Lpr) value significantly decreased under drought stress treatment. This was associated with an increase of root electrolyte leakage, signaling the occurrence of an injury to root cell membranes. At root growth level, stressed plants managed to maintain their root elongation despite decreased root mass. After short period of rehydration, the argane tree plants exhibited a tendency of increased hydraulic conductivity during recovery after drought stress, suggesting that this root physiological response may be intimately linked to drought stress tolerance strategies. These results also could be important to contribute to selection of tolerant genotypes and develop argane tree regeneration programs in regions that suffer from lack of water.

Identification of G2607A mutation in EGFR gene with a significative rate in Moroccan patients with Bladder Cancer.

The epidermal growth factor receptor (EGFR) is involved in the regulation of several cellular processes and in the development of many human cancers. Somatic mutations of EGFR at tyrosine kinase domain have been associated with clinical response to tyrosine kinase inhibitors (TKIs) in lung cancer patients. In this study, we evaluated the frequency of point mutations in EGFR for future use of TKI in clinical treatment of bladder cancer. A total, 50 Moroccan patient specimens with bladder cancer and 48 healthy controls were analysed for EGFR mutations in the region delimiting exons 18-21 by PCR amplification and direct sequencing. Our results showed the absence of mutations in the EGFR kinase domain in these exons in all analysed specimens. However, sequence analysis of the EGFR-TK domain, revealed the presence of (G2607A) polymorphism at exon 20. Statistical analysis showed significant difference in the frequencies of G2607A polymorphism between cancer cases and healthy controls (p=0.0001) and the frequencies of the GG and GA/AA genotypes among the cancer cases were 28% and 72%, respectively. Moreover, allelic frequencies of G2607A polymorphism showed significant difference between cancer cases and healthy controls (p=0.0025). Data analysis showed no significant association between G2607A polymorphism and patients' age, clinical stage and tumor grade (p > 0.05). However, a significant difference was found between this polymorphism and patients' sex that could be a sampling bias due to the very limited number of women with bladder cancer. Our findings highlight that, mutations in EGFR kinase domain is a rare event in bladder cancer, suggesting, that treatment of bladder cancer patients with TKI may not be effective. However, the EGFR G2607A polymorphism in exon 20 is frequent in bladder cancer cases and must be further explored for its relevance in the treatment of this disease.

In-depth characterization of bacterial and archaeal communities present in the abandoned Kettara pyrrhotite mine tailings (Morocco).

In Morocco, pollution caused by closed mines continues to be a serious threat to the environment, like the generation of acid mine drainage. Mine drainage is produced by environmental and microbial oxidation of sulfur minerals originating from mine wastes. The fundamental role of microbial communities is well known, like implication of Fe-oxidizing and to a lesser extent S-oxidizing microorganism in bioleaching. However, the structure of the microbial communities varies a lot from one site to another, like diversity depends on many factors such as mineralogy, concentration of metals and metalloids or pH, etc. In this study, prokaryotic communities in the pyrrhotite-rich tailings of Kettara mine were characterized using the Illumina sequencing. In-depth phylogenetic analysis revealed a total of 12 phyla of bacteria and 1 phyla of Archaea. The majority of sequences belonged to the phylum of Proteobacteria and Firmicutes with a predominance of Bacillus, Pseudomonas or Corynebacterium genera. Many microbial populations are implicated in the iron, sulfur and arsenic cycles, like Acidiferrobacter, Leptospirillum, or Alicyclobacillus in Fe; Acidiferrobacter and Sulfobacillus in S; and Bacillus or Pseudomonas in As. This is one of the first description of prokaryotic communities in pyrrhotite-rich mine tailings using high-throughput sequencing.

Assessment of the Nature and Severity of Pain Using SF-MPQ for Cancer Patients at the National Institute of Oncology in Rabat in 2015.

BACKGROUND: Cancer is a worldwide health problem and pain is among the most common and unpleasant effects affecting well-being of cancer patients. Accurate description of pain can help physicians to improve its management. Many English tools have been developed to assess pain. Only a limited number of these are applied in Arab countries. Our aim was to assess the quality, the nature and the severity of pain using the short McGill Pain Questionnaire (SF-MPQ) on cancer patients in the National Institute of Oncology (NIO) in Rabat, Morocco. MATERIALS AND METHODS: The tool used was the SF-MPQ inspired from the Arabic version of the MPQ. The subjects were cancer patients (N=182) attending the NIO, from 24th October 2015 to 8th January 2016, ≥18 years old, experiencing pain and coming to have or to update their pain medication. RESULTS: The rate of participation was 96.3%. Eight patients haddif culties to express their pain using descriptors, but could use the Visual Analogue Scale (VAS) and the body diagram. The most frequent sensory descriptors were 'Throbbing', 'Shooting', 'Hot-Burning'. The most used affective descriptor was 'Tiring-Exhausting'. The mean VAS was 6.6 (2.4). The mean score of all items was 11.9 (7.8). The patients were suffering from severe pain. The internal consistency of the form was acceptable. CONCLUSIONS: The findings indicate that most of the patients attending the pain center of the NIO could use the descriptors of the SF-MPQ to describe their pain. They indicate the usefulness of the SF-MPQ to assess the nature and the severity of pain in cancer patients. This tool should now be tested in other Moroccan and Arabic contexts associated with other tools in clinical trials.

Characterisation of Phaseolus symbionts isolated from Mediterranean soils and analysis of genetic factors related to pH tolerance.

The ultimate objective of PhIMED, in which two European (Germany, Italy) and two Mediterranean (Morocco, Egypt) countries collaborate, is to improve the cultivation of French bean (Phaseolus vulgaris) under arid and semi-arid conditions by analysing and enhancing stress tolerance of the nitrogen fixing rhizobial microsymbionts. Rhizobial strains nodulating P. vulgaris (RP strains) isolated from areas in Morocco frequently subjected to drought were analysed for their salt and pH tolerance and their phylogenetic relationship. Strain RP163, exhibiting high nodulation efficiency and a broad pH tolerance was mutagenised by Tn5 and mutants unable to grow on extreme pH media were isolated. Some of the mutants affected in low pH tolerance were found to be mutated in genes related to cobalmin biosynthesis and in succinate dehydrogenase (sdhA). In a parallel approach, promoters and genes inducible under extreme pH values were identified in Rhizobium leguminosarum bv. viciae VF39, among them gabT, which encodes the GABA transaminase and which is induced under acidic conditions. The same gene is present and similarly regulated in RP163. The actSR gene region was cloned from VF39, sequenced and mutants generated in this region were found to be impaired in growth at low pH, but also under neutral conditions. The Agrobacterium rhizogenes 'promintron' promoter, reported to be activated in stationary phase, was found to be also strongly induced under acidic conditions in rhizobia and it is currently being characterised to construct a system allowing the expression of stress tolerance genes in bacteroids and free-living bacteria.

Isolation of a bacteriocin-producing Lactococcus lactis subsp. lactis and application to control Listeria monocytogenes in Moroccan jben.

AIM: Use of a bacteriocin-producing lactococcal strain to control Listeria monocytogenes in jben. METHODS AND RESULTS: A Lactococcus lactis strain isolated from lben was shown, by the spot technique, to produce a bacteriocin different from nisin. Inhibitory activity of the bacteriocin-producing strain against Listeria monocytogenes was investigated in jben, made from cow's milk fermented with the producer organism and contaminated with 104 or 107 cfu ml-1. Listeria counts were monitored during manufacture, and during conservation at room and at refrigeration temperatures. Results showed that the pathogen was reduced by 2.7 logarithmic units after 30 h of jben processing when the initial inoculum of 107 cfu ml(-1) was used. For the initial inoculum of 104 cfu ml(-1), the bacterium was completely eliminated at 24 h. Furthermore, the use of the bacteriocin-producing starter culture extended the shelf-life of jben by 5 days. CONCLUSIONS: In situ production of the lactococcal bacteriocin is an efficient biological means of controlling L. monocytogenes in jben and of allowing shelf-life extension. SIGNIFICANCE AND IMPACT OF THE STUDY: The proposed technology will essentially benefit minimally processed dairy products and those made with raw milk.

Phenotypic characteristics of rhizobia isolates nodulating acacia species in the arid and Saharan regions of Morocco.

The phenotypic characteristics of 48 isolates obtained from root nodules of four Acacia species (Acacia cyanophylla, A. gummifera, A. horrida and A. raddiana) growing in soils collected from the arid and Saharan regions of Morocco were studied. The rhizobia were very diverse with respect to their cross-nodulation patterns, as well as their physiological and biochemical properties. Dendrograms obtained through computer numerical analysis of 52 phenotypic characteristics showed that isolates could fit into four clusters below the boundary level of 0.85 average distance and that they were very distinct from the reference strains. Some interesting isolates for inoculation trials have been identified. They were able to grow at pH ranging from 4 to 9, tolerate a high salt concentration (3% NaCl) and grew at a maximum temperature between 35 and 40 degrees C.

Genetic diversity and phylogeny of rhizobia that nodulate acacia spp. in morocco assessed by analysis of rRNA genes

Forty rhizobia nodulating four Acacia species (A. gummifera, A. raddiana, A. cyanophylla, and A. horrida) were isolated from different sites in Morocco. These rhizobia were compared by analyzing both the 16S rRNA gene (rDNA) and the 16S-23S rRNA spacer by PCR with restriction fragment length polymorphism (RFLP) analysis. Analysis of the length of 16S-23S spacer showed a considerable diversity within these microsymbionts, but RFLP analysis of the amplified spacer revealed no additional heterogeneity. Three clusters were identified when 16S rDNA analysis was carried out. Two of these clusters include some isolates which nodulate, nonspecifically, the four Acacia species. These clusters, A and B, fit within the Sinorhizobium lineage and are closely related to S. meliloti and S. fredii, respectively. The third cluster appeared to belong to the Agrobacterium-Rhizobium galegae phylum and is more closely related to the Agrobacterium tumefaciens species. These relations were confirmed by sequencing a representative strain from each cluster.

The energetics of the injection process of bacteriophage lambda DNA and the role of the ptsM/pel-encoded protein.

We have examined the nature of the role played in the process of phage lambda DNA injection by the bacterial protein coded by the ptsM/pel gene. Neither the specific inhibition of the activity of the PtsM protein, nor the addition of inhibitors of phosphotransferase system modified the efficiency of lambda DNA penetration. Thus, the PtsM/Pel protein does not seem to play a role through its transport function, although we have confirmed that it must be present for a successful lambda DNA injection. Moreover, the presence of various metabolic inhibitors (uncouplers, cyanide, arsenate) separately or together, or even harsher methods of energy depletion did not prevent lambda DNA penetration, suggesting that DNA is entering the cell cytoplasm by diffusion.

Host cell metabolic energy is not required for injection of bacteriophage T5 DNA.

The addition of various metabolic inhibitors (uncouplers, cyanide, arsenate, ionophores) separately or together (for example, arsenate and an uncoupler) or even harsher methods of energy depletion did not prevent bacteriophage T5 from injecting its first-step-transfer DNA (a DNA segment 3 micron long) into the cytoplasm of host cells. The same indifference to metabolic energy was observed if first-step-transfer DNA was decapsidated and uncoiled before injection, thus precluding any energetic help from the phage capsid or from some tension stored in DNA tightly packed in the head. Penetration of the second-step-transfer DNA across the cytoplasmic membrane was studied by determining injection of superinfecting T5 A2- amber phages into Sup- bacteria containing proteins A1 and A2 previously encoded by the first-step-transfer DNA of a primary wild-type phage. The addition of various metabolic inhibitors after synthesis of proteins A1 and A2 but before superinfection did not prevent this penetration of second-step-transfer DNA. Thus, we conclude that traversal of the cytoplasmic membrane by the entire T5 DNA (a molecule 34 micron long) must occur by diffusion through protein channels.