The type of interaction between tumor-associated antigens and specialized antigen-presenting cells such as dendritic cells (DCs) is critical for the type of immunity that will be generated. MUC1, a highly O-glycosylated mucin, is overexpressed and aberrantly glycosylated in several tumor histotypes. This results in the expression of tumor-associated glycoforms and in MUC1 carrying the tumor-spe...

Myxococcus xanthus is a Gram-negative, soil-dwelling bacterium that glides on surfaces, reversing direction approximately once every 6 min. Motility in M. xanthus is governed by the Che-like Frz pathway and the Ras-like Mgl pathway, which together cause the cell to oscillate back and forth. Previously, Igoshin et al. (2004) suggested that the cellular oscillations are caused by cyclic changes i...

Biological uranium reduction was investigated using bacteria isolated from a uranium mine in Limpopo, South Africa. Background uranium concentration in soil from the mine was determined to be 168 mgkg(-1) much higher than the typical background uranium concentration in natural soils (0.30-11.7 mgkg(-1)). Therefore it was expected that the bacteria isolated from the site were resistant to U(VI) ...

The growth properties and biodegradation mechanism of a Gram-negative bacterium, Pseudomonas nitroreducens TX1 that was able to grow on branched octylphenol polyethoxylates (OPEO(n), average n=9.5) as the sole carbon source over a wide concentration range (1-100,000 mgl(-1)) were studied. Analysis of growth factors indicated the highest specific growth rate (micro) of 0.53 h(-1) was obtained at...

We used a combination of genomic techniques to monitor chromosomal evolution across hundreds of generations as Escherichia coli adapted to growth-limiting concentrations of either lactulose, methyl-galactoside, or a 72:28 mixture of the two. DNA microarrays identified 8 unique duplications and 16 unique deletions among 42 evolvants from 23 chemostat experiments. Each mutation was confirmed by s...

Perpendicular orientation of the electron donor in relation to the acceptor in the ground state seems to contribute significantly to high rate constants of the photoinduced intramolecular electron transfer (PET) in electron donor-acceptor (DA) type molecules [1]. A very interesting class of molecules in this respect are systems build around a spiro-type carbon atom, separating mutually orthogon...

Doris E. Vidal ABSTRACT Resistance to contaminants is an important yet unmeasured factor in sediment toxicity tests. The rate at which mercury resistance develops and its genetic persistence in the oligochaete worm Tubifex tubifex were studied under laboratory conditions. Two populations of T. tubifex worms were raised for four generations each in clean and mercurycontaminated sediments, respec...

This study shows that a short-term respirometric measurement based on the rate of oxygen uptake needed to oxidize glucose is a reliable and fast method to assess biocide efficacy against P. fluorescens cells. Respiratory activity using oxygen consumption rate, the determination of viable and nonviable cells using Live/Dead BacLight kit and colony formation units (CFU), were compared as indicato...

This study aimed to investigate the toxicological effects of the LAS-C12 on Mugil platanus (mullet). Fishes exposed to 1.0 mg.L for 24, 48, 72, 96 and 120 hours presented significant increase in specific routine metabolism. At the concentration of 0.5 mgL, the active metabolism presented a decreasing trend from 48 h of exposure on. However, only the consumption averages for 72 h were statistica...