The biosorption of several toxic heavy metals (Pb, Cd, Co, Ni, Zn and Cu) by the exopolysaccharide (EPS) produced by Paenibacillus jamilae, a potential biosorbent for metal remediation and recovery was studied. Firstly, the biochemical composition of this bacterial polymer was determined. Glucose was the most abundant neutral sugar, followed by galactose, rhamnose, fucose and mannose. The polymer presented a high content of uronic acids (28.29%), which may serve as binding sites for divalent cations. The presence of carboxylic groups was also detected by infrared spectroscopy. The EPS presented an interesting affinity for Pb in comparison with the other five metals. Lead biosorption (303.03 mg g -1 ) was tenfold higher (in terms of mg of metal adsorbed per gram of EPS) than the biosorption of the rest of metals. Biosorption kinetics, the effect of pH and the effect of competitive biosorption were determined. Finally, we found that the EPS was able to precipitate Fe(III), but the EPS-metal precipitate did not form with Fe(II), Pb(II), Cd(II), Co(II), Ni(II), Cu(II) and Zn(II).

A novel extremely halophilic archaeon was isolated from Ezzemoul sabkha, Algeria. The strain, designated 5.1 T , was neutrophilic, motile and Gram-negative. At least 15 % (w/v) NaCl was required for growth. The isolate grew at pH 6?5-9?0, with optimum growth at pH 7?0-7?5. Mg 2+ was required for growth. Polar lipids were C 20 C 20 derivatives of phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester, and phosphatidylglycerol sulfate and sulfated diglycosyl diether. The genomic DNA G+C content of strain 5.1 T was 61?9 mol% (T m ). Phylogenetic analysis based on comparison of 16S rRNA gene sequences revealed that strain 5.1 T clustered with Halorubrum species. The results of DNA-DNA hybridization and biochemical tests allowed genotypic and phenotypic differentiation of strain 5.1 T from other Halorubrum species. The name Halorubrum ezzemoulense sp. nov. (type strain 5.1 T =CECT 7099 T =DSM 17463 T ) is proposed.

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 C 16 : 0 and C 18 : 1 v9c. Other fatty acids present were C 16 : 1 v9c, C 18 : 0 10-methyl, C 12 : 0 3-OH, C 10 : 0 and C 12 : 0 . The G+C content of the genomic DNA was 56?0 mol%. 16S rRNA gene sequence analysis indicated that strain B2 T was closely related to Salicola marasensis in the Gammaproteobacteria. The level of 16S rRNA gene sequence similarity between strain B2 T and the type strain of Salicola marasensis was 99 %. DNA-DNA hybridization experiments between strain B2 T and Salicola marasensis indicated a level of relatedness of 52 %.The phenotypic characteristics of strain B2 T allowed its differentiation from recognized species of the genus Salicola. Strain B2 T 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 B2

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.During the preparation of edible olives according to the procedure used to give so-called 'Spanish green olives', residual wash-water (EWW, edible-olive wash-water) is generated as a waste product. In this process, the olives are treated with brines which contain 10-13 % (w/v) NaCl, in which they undergo lactic fermentation (Brenes & de Castro, 1997). The brines represent a large proportion of the total contaminating discharges from the olive industry. However, specific treatments for these wash-waters are either nonexistent or ineffective (Romero Barranco et al., 2001). To obtain a better insight into the microbial community present in EWW, we analysed the microbial content. In the present study, we report the description of a novel aerobic, mesophilic, endospore-forming organism isolated from EWW that was able to grow in 0-20 % NaCl.Initially, 180 strains were isolated from samples of EWW (provided by AgroSevilla S.A., La Roda, Sevilla, Spain) obtained at different stages of the edible olive processing. Isolation was performed by the standard dilutionplating technique on HM medium (Ventosa et al., 1982) supplemented with a balanced mixture of sea salts with 10 % (w/v) NaCl (Rodríguez-Valera et al., 1981) at 30 u C. Strains were maintained on HM medium (Ventosa et al., 1982) supplemented with 5 % (w/v) sea-salt solution (referred to here as HM 5 % sea salts medium) (Rodríguez-Valera et al., 1981). The predominant strains present in this wash-water were Gram-positive, endospore-forming bacilli. For this study, of the 180 isolated strains, four were selected on the basis of their similar physiological characteristics.Cell morphology was examined by light microscopy and transmission electron microscopy using cells from exponentially growing cultures. Endospores were stained accor...

ABSTRACT Referential expressions (REs) have been investigated in L2 English but to date there is no single study that systematically and simultaneously analyzes the development and acquisition of the multiple factors that constrain the choice of REs in natural discourse production. We investigate L1 Spanish–L2 English learners across three proficiency levels versus an English control group from the COREFL corpus. An analysis of both the RE and its antecedent(s) reveals that different intra- and extralinguistic factors constrain the choice of REs (information status, activated antecedents, syntactic configurations, characterhood, within-task effect, and proficiency level). L2 learners (L2ers) are sensitive to some factors but are unable to fully attain native-like levels even at advanced stages. They do not transfer null subjects from their L1 contrary to previous L2 research, and do not find all contexts at the syntax-discourse interface equally problematic, thus confirming previous theoretical proposals and empirical findings.