A Multi-Omics Approach Reveals New Signatures in Obese Allergic Asthmatic Children.

Background: Asthma is a multifactorial condition where patients with identical clinical diagnoses do not have the same clinical history or respond to treatment. This clinical heterogeneity is reflected in the definition of two main endotypes. We aimed to explore the metabolic and microbiota signatures that characterize the clinical allergic asthma phenotype in obese children. Methods: We used a multi-omics approach combining clinical data, plasma and fecal inflammatory biomarkers, metagenomics, and metabolomics data in a cohort of allergic asthmatic children. Results: We observed that the obese allergic asthmatic phenotype was markedly associated with higher levels of leptin and lower relative proportions of plasma acetate and a member from the Clostridiales order. Moreover, allergic children with a worse asthma outcome showed higher levels of large unstained cells, fecal D lactate and D/L lactate ratio, and with a higher relative proportion of plasma creatinine and an unclassified family member from the RF39 order belonging to the Mollicutes class. Otherwise, children with persistent asthma presented lower levels of plasma citrate and dimethylsulfone. Conclusion: Our integrative approach shows the molecular heterogeneity of the allergic asthma phenotype while highlighting the use of omics technologies to examine the clinical phenotype at a more holistic level.

Characterisation of Paenibacillus jamilae strains that produce exopolysaccharide during growth on and detoxification of olive mill wastewaters.

A total of 10 bacterial strains were isolated from a compost of corn treated with olive mill wastewaters (OMW) and selected by their capacity to synthesize exopolysaccharides (EPS). Morphological, physiological, biochemical and nutritional tests were used for a phenotypic study. A numerical analysis showed that all strains were 90% similar to each other. A DNA-DNA hybridization assay confirmed that all the strains belonged to Paenibacillus jamilae species. All the characterized strains were able to produce EPS growing on OMW batch cultures. The strain which was able to produce the highest EPS yield was chosen to perform an assay for testing its putative detoxifying activity, and it showed to reduce more than half the toxic capacity of the OMW. The results presented in this study, indicated the possible perspectives for using these bacterial strains to produce EPS and contribute to the bioremediation of the waste waters that are produced in the olive oil elaboration process.

Virgibacillus olivae sp. nov., isolated from waste wash-water from processing of Spanish-style green olives.

Four bacterial strains (E(30)8(T), E(55)49, I(30)77 and N(30)129) were isolated from the residual wash-water produced during the processing of Spanish-style green table olives. The isolates were subjected to a polyphasic taxonomic study using phenotypic, phylogenetic and genotypic methods. The bacteria were Gram-positive, spore-forming rods. Moreover, they were heterotrophs that were able to utilize cellobiose, glucose, mannose and rhamnose as carbon sources. The G+C content of their genomic DNA ranged from 30.7 to 33.4 mol%. The major cellular fatty acids found in strain E(30)8(T) were iso-C(15 : 0), anteiso-C(15 : 0), iso-C(17 : 0) and anteiso-C(17 : 0). DNA-DNA hybridization shows 76.2-88.3 % relatedness among the four strains. The 16S rRNA gene sequence of isolate E(30)8(T) shows that it belongs to the genus Virgibacillus, with the highest sequence similarity (99 %) to Virgibacillus marismortui 123(T). However, phenotypic differences and DNA-DNA relatedness between strain E(30)8(T) and V. marismortui ATCC 700626(T) of less than 47 % suggest the placement of these strains within a novel species of the genus Virgibacillus. The name Virgibacillus olivae sp. nov. is proposed, with strain E(30)8(T) (=LMG 23503(T)=DSM 18098(T)) as the type strain.

Production and characterization of the exopolysaccharide produced by Paenibacillus jamilae grown on olive mill-waste waters.

Paenibacillus jamilae, a strain isolated from compost prepared with olive-mill wastewaters, produced an extracellular polysaccharide (EPS) when it was grown in a culture containing olive-mill waste waters (OMWW) as sole carbon and energy sources. Maximal EPS production in 100 mL batch-culture experiments (5.1 g L(-1)) was reached with a concentration of 80% of OMWW as fermentation substrate (v/v). Although an inhibitory effect was observed on growth and EPS production when OMWW concentration was increased, an appreciable amount of EPS (2.7 g L(-1)) was produced with undiluted OMWW. Sepharose CL-2B chromatography showed that the EPS presented two fractions, EPS I (>2000 kDa) and EPS II (500 kDa). Both fractions were characterized by GC-MS as two different acidic heteropolysaccharides containing glucose, galactose and mannose as the major components. The performed study made evident the possibility of using OMWW as substrate for the production of EPS by P. jamilae with a satisfactory yield.

Salicola salis sp. nov., an extremely halophilic bacterium isolated from Ezzemoul sabkha in Algeria.

A novel, extremely halophilic bacterium was isolated from brine samples collected from Ezzemoul sabkha in north-east Algeria. Cells of this isolate, designated B2T, were Gram-negative, rod-shaped and motile. Growth occurred between 10 and 25% (w/v) NaCl and the isolate grew optimally at 15-20% (w/v) NaCl. The pH range for growth was 6.0-9.0 with an optimum at pH 7.0-7.5. The predominant fatty acids were C16:0 and C18:1omega9c. Other fatty acids present were C16:1omega9c, C18:0 10-methyl, C12:0 3-OH, C10:0 and C12:0. The G+C content of the genomic DNA was 56.0 mol%. 16S rRNA gene sequence analysis indicated that strain B2T was closely related to Salicola marasensis in the Gammaproteobacteria. The level of 16S rRNA gene sequence similarity between strain B2T and the type strain of Salicola marasensis was 99%. DNA-DNA hybridization experiments between strain B2T and Salicola marasensis indicated a level of relatedness of 52%. The phenotypic characteristics of strain B2T allowed its differentiation from recognized species of the genus Salicola. Strain B2T was able to hydrolyse starch but not aesculin. It was unable to use carbohydrates and could not use citrate, pyruvate or succinate as sole carbon and energy sources. On the basis of the polyphasic data presented, strain B2T is considered to represent a novel species of the genus Salicola, for which the name Salicola salis sp. nov. is proposed. The type strain is B2T (=CECT 7106T=LMG 23122T).

Production of a metal-binding exopolysaccharide by Paenibacillus jamilae using two-phase olive-mill waste as fermentation substrate.

The present study investigated the use of two-phase olive mill waste (TPOMW) as substrate for the production of exopolysaccharide (EPS) by the endospore-forming bacilli Paenibacillus jamilae. This microorganism was able to grow and produce EPS in aqueous extracts of TPOMW as a unique source of carbon. The effects of substrate concentration and the addition of inorganic nutrients were investigated. Maximal polymer yield in 100-ml batch-culture experiments (2 g l(-1)) was obtained in cultures prepared with an aqueous extract of 20% TPOMW (w/v). An inhibitory effect was observed on growth and EPS production when TPOMW concentration was increased. Nutrient supplementation (nitrate, phosphate, and other inorganic nutrients) did not increase yield. Finally, an adsorption experiment of Pb (II), Cd (II), Cu (II), Zn (II), Co (II), and Ni (II) by EPS is reported. Lead was preferentially complexed by the polymer, with a maximal uptake of 230 mg/g EPS.