Degradation of glucosinolates of Nasturtium officinale seeds

Nasturtium officinale contains four glucosinolates, the major representative being 2-phenethylglucosinolate. On autolysis of seeds or leaves, isothiocyanates were the main products of glucosinolate degradation but no thiocyanate was detected. The application of heat during extraction caused an increase in nitrile formation to dominance over isothiocyanates. A (benzyl) thiocyanate-forming extract of Lepidium sativum seeds did not provoke generation of any thiocyanate from glucosinolates of N. officinale (or Barbarea praecox), but it did impose accentuated nitrile-forming properties on the systems. The conclusion is reached that some glucosinolate-containing Cruciferae are predominantly nitrile-producing and some predominantly isothiocyanate-producing, all other factors being constant.     

Abiotic and Biotic Stresses and Changes in the Lignin Content and Composition in Plants

Lignin is a polymer of phenylpropanoid compounds formed through a complex biosynthesis route, represented by a metabolic grid for which most of the genes involved have been sequenced in several plants, mainly in the model-plants Arabidopsis thaliana and Populus. Plants are exposed to different stresses, which may change lignin content and composition. In many cases, particularly for plant-microbe interactions, this has been suggested as defence responses of plants to the stress. Thus, understanding how a stressor modulates expression of the genes related with lignin biosynthesis may allow us to develop study-models to increase our knowledge on the metabolic control of lignin deposition in the cell wall. This review focuses on recent literature reporting on the main types of abiotic and biotic stresses that alter the biosynthesis of lignin in plants.     

The frontier between cell and organelle: genome analysis of <Emphasis Type="Italic">Candidatus</Emphasis> Carsonella ruddii

Background  

Bacterial symbioses are widespread among insects. The early establishment of such symbiotic associations has probably been one of the key factors for the evolutionary success of insects, since it may have allowed access to novel ecological niches and to new imbalanced food resources, such as plant sap or blood. Several genomes of bacterial endosymbionts of different insect species have been recently sequenced, and their biology has been extensively studied. Recently, the complete genome sequence of Candidatus Carsonella ruddii, considered the primary endosymbiont of the psyllid Pachpsylla venusta, has been published. This genome consists of a circular chromosome of 159,662 bp and has been proposed as the smallest bacterial endosymbiont genome known to date.     

Real-time detection of Fe·EDTA/H2O2-induced DNA cleavage by linear dichroism

The conditions for the measurement of linear dichroism (LD) can be adjusted so as to solely reflect the length and the flexibility of DNA. The real-time detection of the EDTA·Fe²⁺-induced oxidative cleavage of double-stranded native and synthetic DNAs was performed using LD. The decrease in the magnitude of the LD at 260 nm, which reflects an increase in the flexibility and a decrease in the length of the DNA, can be described by the sum of two or three exponential curves in relation to the EDTA·Fe²⁺ concentration. The fast component was assigned to the cleavage of one of the double strands, inducing an increase in the flexibility, while the other slower component was assigned to the cleavage of the double strand, resulting in the shortening of DNA. The decrease in the magnitude of the LD of poly[d(A-T)₂] was similar to that of poly[d(I-C)₂], while that of poly[d(G-C)₂] was found to be the slowest, indicating that the resistance of poly[d(G-C)₂] against the Fenton-type reagent was the strongest. This observation suggests that the amine group in the minor groove of the double helix may play an important role in slowing the EDTA·Fe²⁺-induced oxidative cleavage.     

DROSOPHILA S2 cell culture in a WAVE Bioreactor: potential for scaling up the production of the recombinant rabies virus glycoprotein

Applied Microbiology and Biotechnology - The transmembrane rabies virus glycoprotein (RVGP) is the main antigen of vaccine formulations used around the world to prevent rabies, the most lethal...