Amino acid sequence of cinnamomin, a new member of the elicitin family, and its comparison to cryptogein and capsicein

AbstractThe phytopathogenic fungi Phytophthora cinnamomi cause systemic leaf necrosis on its non-host tobacco; in culture, it secretes a protein, called cinnamomin, which elicits leaf necrosis and protects tobacco against the pathogen Phytophthora nicotianæ, in a way similar to cryptogein and different from capsicein, elicitins of known amino acid sequences. The cinnamomin sequence has been determined and compared to other elicitins. The differences in the 3 elicitin sequences were correlated to the biological acivities: 2 lysines were ascribed as the key amino acids involved in the differential control of protection with respect to necrosis

The impact of compaction, moisture content, particle size and type of bulking agent on initial physical properties of sludge-bulking agent mixtures before composting

This study aimed to experimentally acquire evolution profiles between depth, bulk density, Free Air Space (FAS), air permeability and thermal conductivity in initial composting materials. The impact of two different moisture content, two particle size and two types of bulking agent on these four parameters was also evaluated. Bulk density and thermal conductivity both increased with depth while FAS and air permeability both decreased with it. Moreover, depth and moisture content had a significant impact on almost all the four physical parameters contrary to particle size and the type of bulking agent

Structure-function relationships of tt and p elicitins, signal proteins involved in the plant-Phytophthora interaction

Abstract. Elicitins form a family of 10-kDa holoproteins secreted by various Phytophthora species. The large-scale purification of parasiticein, a novel elicitin secreted by P. parasitica, led to the determination of its sequence. We have compared the necrotic activities and the primary and secondary structures (determined through circular dichroism) of four elicitins. On tobacco plants, they could be classified into two classes: a, comprising capsicein and parasiticein (less necrotic), and ]3, comprising cryptogein and cinnamomin (very toxic with a necrosis threshold of 0.1 i~g per leaf). The features of elicitin structure which might be involved in the interaction of elicitins with the leaf target cells and that could explain the different necrosis-inducing properties of the two proteins are investigated. About 75% sequence identity was observed between the four elicitins: only two short terminal regions are heterologous, while the central core is mainly conserved. The circular-dichroism spectra showed that the secondary structure of the elicitins was largely conserved. All of them consisted of approx. 50% a-helix with little or no [3-structure. Comparisons of the complete sequences, amino-acid compositions, isoelectric points, hydropathy indices and th e secondary-structure predictions correlated with the necrotic classification. Alpha elicitins corresponded to acidic molecules with a valine residue at position 13, while 13 elicitins were basic with a lysine at this position, which appeared to be a putative active site responsible for necrosis induction

A new strategy for primary structure determination of proteins: Application to bovine β-casein

AbstractA new approach has been developed for sequencing proteins. A radioactive label is attached specifically to the C-terminus of the protein. The labelled molecule is subjected to varying proteolysis conditions. From the electrophoretic patterns (SDS-PAGE) of the hydrolysates, appropriate cleavage conditions are selected, giving labelled peptides of different lengths which are purified. The labelled peptides are sequenced in order of increasing size (from 1 to n), peptide (i) being sequenced until the N-terminal sequence of peptide (i-1) is encountered. This approach allows the determination of a complete protein sequence with a minimal number of Edman cycles. The method was successfully applied to bovine β-casein (209 residues) which was completely resequenced with only 239 Edman cycles

Older drivers' self-regulation: discrepancy reduction or region of proximal learning?

We examined older adults' self-regulation within the region of proximal learning (RPL) framework. Younger and older drivers completed four circuits of increasing difficulty in a driving simulator and were then given a limited amount of time to train for a test. While older drivers chose to train on easier circuits than younger ones, both age groups focused on the easier circuits first, only moving to the more difficult ones later. They were thus equally able to identify their RPL. This framework appears to apply beyond the obvious scope of metamemory and provides a behavioral assessment of self-regulation in driving settings

Les fondements anthropologiques de l’autorité

International audienceL'autorité, une question anthropologique Lorsque nous parlons communément d'autorité, nous pensons savoir de quoi il s'agit. Nous considérons en effet que, sans elle, aucune situation ne peut être traitée, qu'aucun savoir ou savoir-faire ne peut être reconnu, qu'aucun métier ne peut s'exercer convenablement et apporter les satisfactions attendues, qu'aucune décision ne peut être aisément acceptée et appliquée. Cela vaut dans toutes les sociétés et à toute époque. L'autorité est donc une propriété fondamentale de l'homme, et indispensable dans la construction permanente de ses relations avec ses semblables. En même temps, elle ne cesse de faire problème, d'être à la fois contestée et revendiquée. Les débats sur l'autorité courent tout au long de l'histoire des sociétés et dans toutes les cultures. L'article traite d'abord de la différence à effectuer entre autorité et pouvoir. Il travaille ensuite les conditions à partir desquelles il est possible de parler d'autorité. Enfin, il insiste sur la distinction, essentielle à opérer aux yeux des auteurs, entre légal et légitime

High homology between a trophoblastic protein (trophoblastin) isolated from ovine embryo and α-interferons

AbstractOvine trophoblastic protein B (oTPB), an embryonic protein, is a 20 kDa secretory protein which is synthesized by the ovine conceptus from days 12 to 22 of pregnancy. oTPB was purified by HPLC using ion-exchange chromatography on a DEAE column and was subsequently chromatographed on a reversed-phase column. Automated Edman degradation was then used to determine the N-terminal amino acid sequence up to 45 residues. The sequence data reveal a significant homology between oTPB and bovine interferons α of class II: 64% of the amino acids are identical and 75% are homologous. A highly conserved region including residues 23–44 exhibits 82% homology. Identity between oTPB and either HuIFN-α.9 or MuIFNα. 1 is 55%. These alignments between oTPB and IFNs occur at the N-terminus of the mature proteins and proceed without deletion. These results suggest that oTPB is an embryonic interferon