Enhanced tolerance to boron toxicity in two-rowed barley by marker-assisted introgression of favourable alleles derived from Sahara 3771

Boron (B) is an essential micronutrient for higher plant, but toxic levels can seriously diminish grain yield in cereal crops by affecting root growth, and thus restricting water extraction from the subsoil. Amelioration of high concentrations in soils is expensive and not always feasible, so breeding for B tolerance is the most viable alternative. This article reports the marker-assisted (MAS) transfer of favourable alleles from an unadapted six-rowed barley (Hordeum vulgare L.) variety, Sahara 3771, into two-rowed lines adapted to southern Australia. During the backcrossing process, the SSR marker, EBmac679, located on chromosome 4H was used to control the target region in foreground selection, but no background selection was applied. Gene introgression was confirmed with 40 BC₆F₁-derived doubled haploid lines segregating for the SSR marker EBmac679. We used a combination of molecular and conventional assays to unequivocally classify the 40 BC₆F₁-derived DH lines as B tolerant or sensitive, and then compared their means for grain yield measured over 2 years and four locations. Results showed modest improvements in grain yield of lines carrying B tolerance genes at some B toxic environments, and negative impact at others. Our results also showed that malting quality profile was not adversely affected through the introgression of the B tolerance allele from Sahara 3771, allowing the newly developed material to be used by breeding programs without risk of a penalty on malt quality.     

Thermolysis of sucrose in the presence of alcohols. A novel method for the synthesis of d-fructofuranosides

When sucrose is thermolyzed in the presence of alcohols, either neat or in dimethyl sulfoxide solution, the products are mainly d-glucose and the appropriate alkyl d-fructofuranosides. Conditions have been investigated for optimizing the yields of the latter products, with a view to utilization of the reaction as a synthetic method. Such sterically hindered alcohols as 2-methyl-2-propanol and three sterols did not readily take part in the reaction. Phenols appear to undergo the reaction, but the phenyl d-fructofuranosides are probably degraded subsequently, to give increased yields of 2,6-anhydro-d-fructofuranose.     

Measurement of ion-induced noise in atmospheric counting chambers,and a novel chamber for its elimination

Atmospheric small-ion enhancement is widely employed in medical, physiological and horticultural research. Accurate measurements of both positive and negative ion concentrations are then essential, but in the face of the high ion ratios encountered — up to 10³ — the classical two-electrode counter is unable to measure the ion of low concentration. It is found that the reading is obliterated by noise.The phenomenon is demonstrated and the theory of counting chambers is extended to include it. A novel three-electrode chamber which is free from ion-induced noise is then designed and the Paper concludes with the test results obtained by its use.     

Cholecystokinin elevates cytosolic calcium in small cell lung cancer cells

The ability of cholecystokinin (CCK) to elevate intracellular Ca2+ levels in small cell lung cancer cells was investigated using the fluorescent Ca2+ indicator Fura 2. CCK-8 elevated the cytosolic Ca2+ levels in cell line NCI-H345 in a dose dependent manner. Nanomolar concentration of CCK-8 elevated cytosolic Ca2+ levels in the absence or presence of extracellular Ca2+. Potent CCK agonists such as gastrin-1 and nonsulfated CCK-8 but not inactive compounds such as CCK-27-32-NH2 elevated cytosolic Ca2+ levels. These data suggest that CCK receptors may regulate the release of Ca2+ from intracellular organelles in small cell lung cancer cells.     

Geometry of phage head construction.

The process of phage capsid assembly is reviewed, with particular attention to the probable role of curvature in helping to determine head size and shape. Both measures of curvature (mean curvature and Gaussian curvature, explained in Appendix I), should act best when the assembling shell is spherical, which could account for procapsids having this shape. Procapsids are also relatively thick, which should help head size determination by the mean curvature. The accessory role of inner and outer scaffolds in size determination and head nucleation is also reviewed.Nucleation failure generates various malformations, including non-closure, but the most common is the tube or polyhead, where the subunits' inherent curvature is expressed as a constant mean curvature. This induces lattice distortions that only partly understood. An extra tubular section in normal heads leads to the prolate shape, with a more complex and variable geometry.Newly assembled procapsids are both enlarged and toughened by the head transformation. In the procapsid the Gaussian curvature is uniformly distributed. But toughening tends to equalize bond lengths, so all the Gaussian curvature gets concentrated in the vertices, being zero elsewhere. This explains head angularization. Because of this change in Gaussian curvature, the regular subunit packing in the polyhedral head cannot be mapped onto the procapsid. This explains part of the hexon distortions found in this region.The implications of translocase-induced DNA twist, end rotation and the coiling of packaged DNA, are discussed.The symmetry mismatches between the head, connector and tail are discussed in relation to the possible alpha-helical structures of their DNA channels.     

Lipidomic profiling of model organisms and the world's major pathogens

Lipidomics is a subspecialty of metabolomics that focuses on water insoluble metabolites that form membrane barriers. Most lipidomic databases catalog lipids from common model organisms, like humans or Escherichia coli. However, model organisms' lipid profiles show surprisingly little overlap with those of specialized pathogens, creating the need for organism-specific lipidomic databases. Here we review rapid progress in lipidomic platform development with regard to chromatography, detection and bioinformatics. We emphasize new methods of comparative lipidomics, which use aligned datasets to identify lipids changed after introducing a biological variable. These new methods provide an unprecedented ability to broadly and quantitatively describe lipidic change during biological processes and identify changed lipids with low error rates.