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Biosurfactant production by Pseudomonas aeruginosa EBN-8 mutant was studied in shake flasks on separate wastes from canola, soybean and corn oil refineries. Of the substrates tested, canola oil refinery waste (COD=20 g l−1) supplemented with sodium nitrate (at COD/N=20) showed the best microbial growth (4.50 g l−1) and rhamnolipid production (8.50 g l−1), at 10 d of incubation with the specific growth rate of 0.316 h−1 and specific product yield of 0.597 g g−1 h. Its cell-free supernatant showed the critical micelle dilution (CMD) of 150 and surface tension (ST) of 28.5 mN m−1.  相似文献   
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International Journal of Peptide Research and Therapeutics - Klebsiella oxytoca is a gram-negative bacterium. It is opportunistic in nature and causes hospital acquired infections....  相似文献   
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The precise characterization of post translational modifications (PTMs) is important for the understanding of protein regulatory mechanisms and their role in disease. However, experimental studies on PTMs, especially with multifunctional proteins are difficult to follow and investigate. Bioinformatic tools are therefore helpful in predicting key protein modifications. To study the role of PTMs in claudin proteins, specifically claudin-1, -3 and -4 in the onset or progression of human cancers, we performed an in silico study of various PTMs and investigated their interplay. Given that the activity of claudins is known to be influenced by two types of PTMs, specifically palmitoylation and kinase- dependent phosphorylation, we predicted two conserved regions in the topological domains of claudin-1, -3 and -4 as potential palmitoylation sites. Furthermore, conserved phosphorylation residues, which may be targets for kinases and can alter claudin’s ability to maintain the integrity of tight junctions, were identified. To our knowledge, this is the first report to suggest O-glycosylation of claudin proteins, as well as a potential novel interplay between phosphorylation and O-glycosylation at Yin Yang sites. Thus, our findings may facilitate the production of anti-cancer drugs, and suggest that novel therapeutic strategies should target post translational events.  相似文献   
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One group of commonly found parasites in birds, for which fitness consequences and effects on life history traits have been much debated are Haemosporidian blood parasites. In a long term study population of great reed warblers Acrocephalus arundinaceus in Sweden, previous studies have shown that the Haemosporidian blood parasites are in their chronic phase during the breeding season and that the fitness of infected and non‐infected birds are similar. In the present study, we quantified parasite intensity (parasitemia) in 718 adults great reed warblers sampled between 1987 and 1998 for the three most common parasite species; Haemoproteus payevskyi (lineage GRW1), Plasmodium ashfordi (GRW2) and Plasmodium relictum (GRW4). We verified that the q‐PCR method is accurately quantifying Haemoproteus payevskyi (GRW1) as it was highly correlated with the number of parasites seen under microscope. Frequency of mixed infections with two lineages was significantly higher than expected based on the prevalence of each of the three parasite lineages. The mean level of parasitemia was significantly different for the three lineages and individual birds had repeatable parasitemia levels between years. Females tended to have a higher parasitemia than males for all three parasite lineages combined. Females with higher GRW1 parasitemia tended to arrive later in spring to their breeding sites. There was a negative correlation between parasitemia and number of fledged offspring for GRW1, and a tendency for a negative correlation between GRW2 parasitemia and the proportion of recruiting offspring. Overall our results demonstrate that chronic Haemosporidian infections can have slight but significant effects on host life history traits, and therefore may act as important selective agents in wild bird populations.  相似文献   
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We investigate high-modulus degradable materials intended to replace metals in biomedical applications.These are typicallycomposites comprising a polylactide(PLA)matrix reinforced with phosphate glass fibres,which provide reinforcementsimilar to E-glass but are entirely degradable in water to produce,principally,calcium phosphate.We have made compositesusing a variety of fibre architectures,from non-woven random mats to unidirectional fibre tapes.Flexural properties in theregion of 30 GPa modulus and 350 MPa strength have been achieved-directly comparable to quoted values for human corticalbone.In collaboration with other groups we have begun to consider the development of foamed systems with structures mimickingcancellous bone and this has shown significant promise.The fibres in these foamed structures provide improved creepresistance and reinforcement of the pore walls.To date the materials have exhibited excellent cellular responses in vitro andfurther studies are due to include consideration of the surface character of the materials and the influence of this on cell interaction,both with the composites and the glass fibres themselves,which show promise as a standalone porous scaffold.  相似文献   
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This paper presents new simple approaches for evaluating determinant and inverse of a matrix. The choice of pivot selection has been kept arbitrary thus they reduce the error while solving an ill conditioned system. Computation of determinant of a matrix has been made more efficient by saving unnecessary data storage and also by reducing the order of the matrix at each iteration, while dictionary notation [1] has been incorporated for computing the matrix inverse thereby saving unnecessary calculations. These algorithms are highly class room oriented, easy to use and implemented by students. By taking the advantage of flexibility in pivot selection, one may easily avoid development of the fractions by most. Unlike the matrix inversion method [2] and [3], the presented algorithms obviate the use of permutations and inverse permutations.  相似文献   
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