Background The sea cucumber lysozyme belongs to the family of invertebrate lysozymes and is thought to be a key defense factor in protecting aquaculture animals against bacterial infection. Recently, evidence was found that the sea cucumber lysozyme exerts broad spectrum antimicrobial action in vitro against Gram-negative and Gram-positive bacteria, and it also has more potent antimicrobial activity independent of its enzymatic activity. To explore the antimicrobial role of this non-enzymatic lysozyme and model its structure to novel antimicrobial peptides, the peptide from the C-terminal amino acid residues 70-146 of the sea cucumber lysozyme in Stichopus japonicus (SjLys-C) was heterologously expressed in Escherichia coli Rosetta(DE3)pLysS. Results The fusion protein system led to over-expression of the soluble and highly stable product, an approximate 26 kDa recombinant SjLys-C protein (rSjLys-C). The present study showed that rSjLys-C displayed strong antimicrobial activity against the tested Gram-positive and Gram-negative bacteria. In particular, the heat-treated rSjLys-C exhibited more inhibitive activity than the native rSjLys-C. The structural analysis of SjLys-C showed that it is a typical hydrophilic peptide and contains a helix-loop-helix motif. The modeling of SjLys-C molecular structures at different temperatures revealed that the tertiary structure of SjLys-C at 100°C underwent a conformational change which is favorable for enhancing antimicrobial activity. Conclusion These results indicate that the expressed rSjLys-C is a highly soluble product and has a strong antimicrobial activity. Therefore, gaining a large quantity of biologically active rSjLys-C will be used for further biochemical and structural studies and provide a potential use in aquaculture and medicine.

Two somatic embryogenesis receptor-like kinase genes (identified as AcSERK1 and AcSERK2) have previously been characterized from pineapple (Ananas comosus). In this work, we describe the characterization of a third gene (AcSERK3) in this family. AcSERK3 had all the characteristic domains and shared extensive sequence homology with other plant SERKs. AcSERK3 expression was studied by in situ hybridization and quantitative real-time PCR to analyze its function. Intense in situ hybridization signals were observed only in single competent cells and competent cell clusters; no hybridization signal was detected in the subsequent stages of somatic embryogenesis. AcSERK3 was highly expressed in embryogenic callus compared to other organs, e.g., 20-80 fold more than in anther but similar to that of non-embryogenic callus, which was 20-50 fold that of anther. AcSERK3 expression in root was 80 fold higher than in anther and the highest amongst all organs tested. These results indicate that AcSERK3 plays an important role in callus proliferation and root development. His-tagged AcSERK3 protein was successfully expressed and the luminescence of His6-AcSERK3 protein was only ~5% of that of inactivated AcSERK3 protein and reaction buffer without protein, and 11.3% of that of an extract of host Escherichia coli pET-30a. This finding confirmed that the AcSERK3 fusion protein had autophosphorylation activity.

In this paper, the solubility of Choline chloride (ChCl) in ethylene glycol (EG) was measured by isothermal method in the temperature range between 0°C and 120°C. The solubility of MgCl2 in saturated ChCl-EG mixture was measured by isothermal method at 20°C, 50°C and 70°C, respectively. Ionic liquid analogous containing MgCl2 was prepared based on the measured solubility data. The structure of the ionic liquid analogous is preliminarily investigated by Fourier transform infrared spectroscopy. The physical and electrochemical properties of the ionic liquid such as viscosity, conductivity, molar conductivity and density were measured as function of temperature and compositions. It was found that magnesium ionic liquid analogous was highly conducting and low viscosity. The ChCl and MgCl2 had a great effect on the studied properties.

O alumínio é um material anódico muito atrativo para baterias de íon lítio quando são melhorados o enfraquecimento rápido de capacidade e os ciclos de desempenho. Para solucionar esses problemas, compósitos de alumínio/carbono foram sintetizados utilizando álcool polivinílico (PVA) como fonte de carbono. As amostras foram caracterizadas por análise termogravimétrica e calorimetria diferencial de varredura (DSC-TGA), análise do tamanho de partículas, difração de raios-X (XRD), microscopia eletrônica de varredura (SEM) e ciclos galvanostáticos. Embora a capacidade irreversível inicial aumente devido à presença do carbono, o compósito exibe um aumento no ciclo de desempenho. O compósito com alto teor de carbono (compósito B) possui retenção de capacidade de 58% após 15 ciclos que é muito maior que a do alumínio puro (21%). Os resultados indicam que o carbono pulverizado é um método possível para melhorar o desempenho eletroquímico do alumínio metálico.

Aluminum is a very attractive anode material for lithium ion batteries if the fast capacity fading and cycle performance are improved. Al/carbon composites were synthesized using polyvinyl alcohol (PVA) as carbon source to solve these problems. The samples were characterized by thermogravimetric analysis and differential scanning calorimetry (DSC-TGA), particle size analysis, X-ray diffraction (XRD), scanning electron microscope (SEM) and galvanostatic cycling. Although the initial irreversible capacities increase due to the presence of carbon, the composites exhibit improved cycle performance. The composite with high carbon content (composite B) possesses capacity retention of 58% after 15 cycles, which is much higher than that of pure aluminum (21%). Results indicate that carbon coating is a feasible method to improve the electrochemical performance of metal aluminum.