Bradyrhizobium sp endosymbiont bacteria nodulate several species of spontaneous leguminous plants of Genisteae tribe from northeastern of Algeria.

218 bacterial isolates obtained from different legume species belonging to the Gensisteae tribe (Lupinus micruntus, Retama sphaerocarpa, Retama raetam and Cytisus vilosus) from different sampling sites in Algeria were studied. Cultivated on YMA medium these strains show a slow growth. The phylogenetic analysis based on 16S rDNA and the household genes of the representatives of these strains indicates that they belong to the genus Bradyrhizobium. A variety of Bradyrhizobium sp. (1, 2, 3) is present in this collection with the presence of strains that can lead to new species. (1) Boulila Farida et al., (2009). Syst. Appl. Microbiol. 32:245?255. (2) Ahnia, et al (2014). Antonie van Leeuwenhoek, J.Microbiol. ISSN 0003-6072, Volume 105 [6] 1121?1129. (3) Bourebaba and al., (2016). Syst. Appl. Microbiol. 39 266?274. This study was supported by the AECID project A1/038234/11. Bourebaba acknowledges support of the National Exceptional. Program (PNE), a fellowship from the Ministry of Higher Education and Scientific research of Algeria at CBGP, Madrid

Characterization of type VI secretion systems (T6SS) of endosymbionts from mimosa or lupine

The T6SS is a nanosyringe that injects proteins into prokaryotic or eukaryotic cells, and it is encoded in the genomes of more than 25% of Gram-negative bacteria (1). We are studying the T6SS of Rhizobium etli Mim1 and Bradyrhizobium sp. LmicA16, symbionts of Phaseolus vulgaris/Leucaena leucocephala and Lupinus micranthus/Lupinus angustifolius/Spartium junceum, respectively. R. etli Mim1 contains a T6SS gene cluster organized in two divergent operons. When the T6SS is active, Hcp, a constituent of the secretory apparatus, can be detected in the extracellular medium (2). Hcp has been immunologically detected in the supernatant of Mim1 cultures. This protein was also detected in bean nodule extracts and in cultures grown in the presence of different legumes exudates. The putative divergent promoters located between the two T6SS gene clusters were analysed by ?- gal fusions. The results showed high levels of expression of the two promoters at high OD and low values at lower ODs. Mutants affected in structural genes induced white nodules with P. vulgaris and L. leucocephala. On the other hand, mutagenesis of T6SS structural genes from LmicA16 strain produced different symbiotic phenotypes. An LmicA16 tssC mutant showed reduced levels of nitrogen fixation on L. micranthus, whereas the same mutant induced the formation of few white, non-fixing nodules on L. angustifolius and S. junceum. (1) Ho et al. (2013) Cell Host Microbe 15:9-21. (2) Wu et al. (2012) PLoS Pathog. 8:1-18 Funded by grants BIO2013-43040-P (MINECO), CGL2011-26932 (MICINN) and AL16-PID-06 (UPM)

Catestatin peptide of chromogranin A as a potential new target for several risk factors management in the course of metabolic syndrome

Obesity, lipodystrophy, diabetes, and hypertension collectively constitute the main features of Metabolic Syndrome (MetS), together with insulin resistance (IR), which is considered as a defining element. MetS generally leads to the development of cardiovascular disease (CVD), which is a determinant cause of mortality and morbidity in humans and animals. Therefore, it is essential to implement and put in place adequate management strategies for the treatment of this disease. Catestatin is a bioactive peptide with 21 amino acids, which is derived through cleaving of the prohormone chromogranin A (CHGA/CgA) that is co-released with catecholamines from secretory vesicles and, which is responsible for hepatic/plasma lipids and insulin levels regulation, improves insulin sensitivity, reduces hypertension and attenuates obesity in murine models. In humans, there were few published studies, which showed that low levels of catestatin are significant risk factors for hypertension in adult patients. These accumulating evidence documents clearly that catestatin peptide (CST) is linked to inflammatory and metabolic syndrome diseases and can be a novel regulator of insulin and lipid levels, blood pressure, and cardiac function. The goal of this review is to provide an overview of the CST effects in metabolic syndrome given its role in metabolic regulation and thus, provide new insights into the use of CST as a diagnostic marker and therapeutic target

In-vivo edema inhibition of Hyoscyamus albus antioxidant extracts rich in calystegines

Calystegines are polyhydroxylated alkaloids that mimic carbohydrate structures. In this study, nortropane alkaloids were extracted from Hyoscyamus albus in order to evaluate their antioxidant and In-vivo anti-inflammatory activities. Gas chromatography-mass spectrometry analysis indicated the presence of several calystegines in the plant (leaves, flowers and seeds), and highlighted the existence of calystegines A and B in seeds and flowers; in fact the occurrence of these two compounds in the plant has been showed for the first time in this study. Antioxidant tests (DPPH, ABTS, reducing power assay and inhibition of human erythrocyte hemolysis mediated by peroxyl free radicals) showed potent activity of seeds calystegines with an EC of 60.83 μg/ml in DPPH scavenging test, TEAC value of 111.4 μmol Trolox/g in ABTS assay and gave 54.03% human membrane RBC hemolysis protection at 2.5 mg/ml. Similar trend was found in anti-inflammatory test, where H. albus extracts showed strong activity, being seeds extract the strongest. This extract enriched in calystegines inhibited mice paw edema induced by carrageenan at 100 and 200 mg/kg 2 h after injection comparably to the standard Indomethacin. In conclusion, seeds extract had the strongest antioxidant and antiinflammatory activity, which can be related with the highest content of calystegines compared to leaves and flowers and this can support the traditional uses of this plant in many countries.Peer Reviewe

Phylogenetic diversity of Bradyrhizobium strains nodulating Calicotome spinosa in the Northeast of Algeria

Fifty-two slow-growing strains were isolated from root nodules of Calicotome spinosa grown in the Northeast of Algeria and grouped in 24 rep-PCR clusters. One representative strain for each profile was further phylogenetically characterized. The nearly complete 16S rRNA gene sequence indicated that all strains were affiliated to Bradyrhizobium. Multi-Locus Sequence Analysis (MLSA) of the atpD, glnII and recA genes and of the 16S-23S rRNA internal transcribed spacer (ITS) showed that these strains formed four divergent clusters: one close to Bradyrhizobium canariense and Bradyrhizobium lupini and three others separate from all the described species, representing three putative new Bradyrhizobium species. A phylogenetic analysis based on the nodC gene sequence affiliated the strains to either of the two symbiovars, genistearum or retamae

Bradyrhizobium sp endosymbiont bacteria nodulate several species of spontaneous leguminous plants of Genisteae tribe from northeastern of Algeria.

218 bacterial isolates obtained from different legume species belonging to the Gensisteae tribe (Lupinus micruntus, Retama sphaerocarpa, Retama raetam and Cytisus vilosus) from different sampling sites in Algeria were studied. Cultivated on YMA medium these strains show a slow growth. The phylogenetic analysis based on 16S rDNA and the household genes of the representatives of these strains indicates that they belong to the genus Bradyrhizobium. A variety of Bradyrhizobium sp. (1, 2, 3) is present in this collection with the presence of strains that can lead to new species. (1) Boulila Farida et al., (2009). Syst. Appl. Microbiol. 32:245?255. (2) Ahnia, et al (2014). Antonie van Leeuwenhoek, J.Microbiol. ISSN 0003-6072, Volume 105 [6] 1121?1129. (3) Bourebaba and al., (2016). Syst. Appl. Microbiol. 39 266?274. This study was supported by the AECID project A1/038234/11. Bourebaba acknowledges support of the National Exceptional. Program (PNE), a fellowship from the Ministry of Higher Education and Scientific research of Algeria at CBGP, Madrid

Characterization of type VI secretion systems (T6SS) of endosymbionts from mimosa or lupine

The T6SS is a nanosyringe that injects proteins into prokaryotic or eukaryotic cells, and it is encoded in the genomes of more than 25% of Gram-negative bacteria (1). We are studying the T6SS of Rhizobium etli Mim1 and Bradyrhizobium sp. LmicA16, symbionts of Phaseolus vulgaris/Leucaena leucocephala and Lupinus micranthus/Lupinus angustifolius/Spartium junceum, respectively. R. etli Mim1 contains a T6SS gene cluster organized in two divergent operons. When the T6SS is active, Hcp, a constituent of the secretory apparatus, can be detected in the extracellular medium (2). Hcp has been immunologically detected in the supernatant of Mim1 cultures. This protein was also detected in bean nodule extracts and in cultures grown in the presence of different legumes exudates. The putative divergent promoters located between the two T6SS gene clusters were analysed by ?- gal fusions. The results showed high levels of expression of the two promoters at high OD and low values at lower ODs. Mutants affected in structural genes induced white nodules with P. vulgaris and L. leucocephala. On the other hand, mutagenesis of T6SS structural genes from LmicA16 strain produced different symbiotic phenotypes. An LmicA16 tssC mutant showed reduced levels of nitrogen fixation on L. micranthus, whereas the same mutant induced the formation of few white, non-fixing nodules on L. angustifolius and S. junceum. (1) Ho et al. (2013) Cell Host Microbe 15:9-21. (2) Wu et al. (2012) PLoS Pathog. 8:1-18 Funded by grants BIO2013-43040-P (MINECO), CGL2011-26932 (MICINN) and AL16-PID-06 (UPM)