Biodegradation of Malathion with Indigenous Acclimated Activated Sludge in Batch Mode and in Continuous-Flow Packed-Bed Reactor

Acclimated activated sludge was examined for its ability to degrade malathion with and without the presence of glucose as a potential cometabolite substrate. In this study, a packed-bed reactor (PBR) using three kinds of biofilm carriers was employed for efficient degradation of malathion. The results obtained indicate that microorganisms tested were able to degrade malathion. The observed degradation rate of the pesticide in the presence of glucose was the same as without glucose. The activated sludge was found to be able to use malathion as the sole phosphorus source. In contrast, the degradation ability of the activated sludge was lost when the pesticide was used as the sole source of sulfur. The degradation capacity of the PBR was higher than the performance obtained with the batch reactor. The reactor packed with crushed olive kernels exhibited the best performance, allowing a total removal of malathion (10 mg/dm³) within 12 h.     

Non-contiguous finished genome sequence and description of Halopiger goleamassiliensis sp. nov.

Halopiger goleamassiliensis strain IIH3^T sp. nov. is a novel, extremely halophilic archaeon within the genus Halopiger. This strain was isolated from an evaporitic sediment in El Golea Lake, Ghardaïa region (Algeria). The type strain is strain IIH3^T. H. goleamassiliensis is moderately thermophilic, neutrophilic, non-motile and coccus-shaped. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 3,906,923 bp long genome contains 3,854 protein-encoding genes and 49 RNA genes (1 gene is 16S rRNA, 1 gene is 23S rRNA, 3 genes are 5S rRNA, and 44 are tRNA genes).     

Synthesis,X-ray structure,in silico calculation,and carbonic anhydrase inhibitory properties of benzylimidazole metal complexes

Three coordination compounds of formula {M(bmim)₂Cl₂} were synthetised (M?=?Co, Zn, and Hg) and fully characterised. Each complex incorporates 1-benzyl-2-methylimidazole (bmim) as ligand. The coordination polyhedron around the metal center for all complexes has a quasi-regular tetragonal geometry. Density functional theory calculations were carried out on the title compounds and as well on hypothetical complexes (Cu, Ni), in order to elucidate their electronic and molecular structure. The calculations reproduced the Co, Zn, and Hg experimental structures and could predict stable complexes in the case of Ni(II) and Cu(II) ions. The carbonic anhydrase (CA, EC 4.2.1.1) inhibitory effects of the three complexes were investigated. Only compound {Hg(bmim)₂Cl₂} (3) exhibited a modest inhibitory effect against hCA I, probably due to the affinity of Hg(II) for His residues at the entrance of the active site cavity.     

Glycation of lysozyme with galactose,galactooligosaccharides and potato galactan through the Maillard reaction and optimization of the production of prebiotic glycoproteins

The production of glycated lysozyme (LZM), with galactose, galactooligosaccharides (GOSs) and potato galactan through the Maillard reaction, was investigated. The percent blocked lysine, estimated from the furosine content, reached a maximum value of 11.2% for LZM:galactan conjugates after 1 day incubation at a a_w of 0.65. A maximum percent blocked lysine of 7.0 and 13.5% were obtained for LZM:galactose/GOS conjugates at a lower a_w of 0.45 after 3 and 7 days, respectively. However, the low percent blocked lysine and the high protein aggregation index of LZM:galactose/GOS conjugates at a_w 0.79 and 0.65 revealed the prevalence of the degradation of the Amadori compounds and the protein cross-linking. Mass spectrometry of LZM conjugates revealed the formation of different glycoforms. Glycated LZMs containing up to seven galactose moieties were formed; while only mono- and diglycated LZMs with GOSs were detected. 2–3 mol of galactan were conjugated to 1 mol of LZM. Response surface methodology, based on a 5-level and 3-factor central composite design, revealed that molar ratio and temperature were the most significant variables for the glycation of LZM with GOSs. The optimal conditions leading to a high percent blocked lysine (16.11%) with a low protein aggregation index (0.11) were identified: temperature of 49.5 °C, LZM:GOS molar ratio of 1:9 and a_w of 0.65. To the best of our knowledge, this is the first study on the optimization of LZM glycation with GOSs.     

Methanosarcina baltica,sp. nov., a novel methanogen isolated from the Gotland Deep of the Baltic Sea

A novel methanogen, Methanosarcina baltica GS1-AT, DSM 14042, JCM 11281, was isolated from sediment at a depth of 241 m in the Gotland Deep of the Baltic Sea. Cells were irregular, monopolar monotrichous flagellated cocci 1.5-3 microm in diameter often occurring in pairs or tetrads. The catabolic substrates used included methanol, methylated amines, and acetate, but not formate or H2/CO2. Growth was observed in a temperature range between 4 degrees and 27 degrees C with an optimum at 25 degrees C. The doubling time with methanol as substrate was 84 h at 25 degrees C, 120 h at 9 degrees C, and 167 h at 4 degrees C. The doubling time with acetate as substrate was 252 h at 25 degrees C and 425 h at 20 degrees C. After the transfer of methanol-grown cultures, long lag phases were observed that lasted 15-20 days at 25 degrees C and 25 days at 4 degrees -9 degrees C. The NaCl optimum for growth was 2%-4%, and the fastest growth occurred within a pH range of 6.5-7.5. Analysis of the 16S rDNA sequence revealed that the strain was phylogenetically related to Methanosarcina. The sequence similarity to described species of <95.7% and its physiological properties distinguished strain GS1-A(T) from all described species of the genus Methanosarcina.     

Stimulation of the DNA unwinding activity of human DNA helicase II/Ku by phosphorylation

The Ku autoantigen is a heterodimeric protein of 70- and 83-kDa subunits, endowed with duplex DNA end-binding capacity and DNA helicase activity (Human DNA Helicase II, HDH II). HDH II/Ku is well established as the DNA binding component, the regulatory subunit as well as a substrate for the DNA-dependent protein kinase DNA-PK, a complex involved in the repair of DNA double-strand breaks and in V(D)J recombination in eukaryotes. The effects of phosphorylation by this kinase on the helicase activity of Escherichia coli-produced HDH II/Ku were studied. The rate of DNA unwinding by recombinant HDH II/Ku heterodimer is stimulated at least fivefold upon phosphorylation by DNA-PK_cs. This stimulation is due to the effective transfer of phosphate residues to the helicase rather than the mere presence of the complex. In vitro dephosphorylation of HeLa cellular HDH II/Ku caused a significant decrease in the DNA helicase activity of this enzyme.     

CFD modelling of wave damping over a fringing reef in the Colombian Caribbean

Coral Reefs - The understanding of physical processes over submerged reefs represents an important ongoing research topic when considering wave energy dissipation and coastal protection that these...     

Comparative analysis of urinary biomarkers for early detection of acute kidney injury following cardiopulmonary bypass

The purpose of this study was to compare the performance of six candidate urinary biomarkers, kidney injury molecule (KIM)-1, N-acetyl-β-D-glucosaminidase (NAG), neutrophil gelatinase-associated lipocalin (NGAL), interleukin (IL)-18, cystatin C and α-1 microglobulin, measured 2?h following cardiopulmonary bypass (CPB) for the early detection of acute kidney injury (AKI) in a prospective cohort of patients undergoing cardiac surgery. A total of 103 subjects were enrolled; AKI developed in 13%. Urinary KIM-1 achieved the highest area under-the-receiver-operator-characteristic curve (AUC 0.78, 95% confidence interval 0.64–0.91), followed by IL-18 and NAG. Only urinary KIM-1 remained independently associated with AKI after adjustment for a preoperative AKI prediction score (Cleveland Clinic Foundation score; p?=?0.02), or CPB perfusion time (p?=?0.006). In this small pilot cohort, KIM-1 performed best as an early biomarker for AKI. Larger studies are needed to explore further the role of biomarkers for early detection of AKI following cardiac surgery.