7 research outputs found
Enzymatic epimerization of bacterial mannuronan and of C(6)-oxidised, galactose-depleted guar: A Circular Dichroism and 1H NMR Study
No full textNUOVI URONANI, ESTERI LINEARI E PRODOTTI RETICOLATI DA GLUCOMANNANI: SINTESI E CARATTERIZZAZIONE
No full textSecondary structure and post-translational modifications of the leucine-rich repeat protein PGIP (Polygalacturonase-Inhibiting Protein) from Phaseolus Vulgaris.
No full textIdentification and characterisation of the Arabidopsis thaliana cell wall proteome: unravelling novel cell wall proteins and new potential functions of the plant extracellular matrix
No full textThe application of the proteomic approach has facilitated efforts directed toward the mapping of the entire Arabidopsis cell wall proteome. Proteins were sequentially extracted from purified cell walls using 0.2 M CaC1(_2) followed by a urea buffer. The extracts were resolved via large format two dimensional polyacrylamide gel electrophoresis (2-D PAGE) and were visualised via Coomassie brilliant blue staining. The aim was to identify and characterise as many cell wall proteins as possible, with the hope of identifying novel cell wall proteins. Out of 325 spots visualised on the 2-D polyacrylamide gel, 144 gave a positive protein identification representing 104 different proteins. The identified proteins were divided into 3 categories. The first category included proteins that have been previously identified as plant cell wall proteins. The second category was designated to include novel cell wall proteins (hypothetical proteins) and the third category was made up of proteins, which had recognised functions, but had never hitherto been known to be secreted to the extracellular matrix. Among the identified novel cell wall proteins there were several that shared high homology with protein kinases. These proteins possessed all the characteristics of secreted polypeptides, such as the cleavable N-terminal signal peptide, and were found to lack both the transmembrane domain and the endoplasmic reticulum retention tetrapeptides (HDEL and KDEL). These observations suggested that, as in animal cells, plant cells had extracellular protein kinase activity (phosphorylation). This was supported by the recent discovery that plant cells secrete ATP to the extracellular matrix (Thomas et al., 2000). Verification of the occurrence of extracellular protein kinase activity was further strengthened by the identification of phosphorylated bona fide cell wall proteins and stress responses caused by the depletion extracellular ATP
Path Dependence, Institutions and the Density of Economic Activities: Evidence from Italian Cities
No full textIn recent years a growing body of literature has begun to consider the possible presence of path dependence in the development processes of countries. This phenomenon has always been recognized in regional and urban studies because the path of development almost naturally follows a history-dependent spatial diffusion influenced by both physical geography and the quality of institutions. In this paper, I consider the case of firm concentration in Italy and its impact on local development. A large and growing literature has argued in favour of persisting effects of past institutions on current outcomes. Hence, in order to identify the impact of firm density on income, I use instruments from the history of a set of Italian cities: namely the presence of a university and status as a free-city state in the Early Middle Ages. I first show that those two variables had an important effect on the process of urban development between 1300 and 1861, together with favourable geographic conditions. Then, when I use these instruments to predict firm density, I find that the elasticity of income to firm density is close to 0.1. This result is interpreted as providing evidence of the historical roots of agglomeration economies in Italy.Path dependence, Urban development, Geography, Institutions, Firm density
Molecular characterization of the Arabidopsis thaliana - Botrytis cinerea interaction
No full textIncludes bibliographical references (leaves 199-253).This study attempted to characterize at a transcriptional level, the defence responses of Arabidopsis thaliana after infection by Botrytis cinerea, using microarrays. The first microarray experiment focused on profiling Arabidopsis genes induced by B. cinerea over time (temporal) while the second investigated spatial expression of Arabidopsis genes from the point of inoculation. A number of genes were up- and down-regulated specifically at 12 hrs, others at 24 hrs while others were up- and down-regulated at both time points. Similarly, some genes were specifically induced very close to the lesion while others in more distal tissue
