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Παράρτημα Ι: Αποτελέσματα έρευνας μαθητών πρωτοβάθμιας εκπαίδευσης που συμμετείχαν σε δράσεις ενισχυτικής διδασκαλίας του προγράμματος «Εκπαίδευση των παιδιών Ρομά» την περίοδο 2010-2014
No full textΜέγεθος δείγματος/ γεωγραφική κάλυψη: 162 πλήρως συμπληρωμένα ερωτηματολόγια μαθητών Ρομά πρωτοβάθμιας εκπαίδευσης
Χρονικό διάστημα συλλογής στοιχείων: Νοέμβριος – Δεκέμβριος 201
Βιοτικοί Πόροι- Τεχνικές Μελέτης και Αξιολόγησης Διάλεξη 4: Βιοποικιλότητα και οικοσυστημικές διεργασίες
Get PDFΑνθεκτικότητα βιο-υµενικών κυττάρων Salmonella Typhimurium και Staphylococcus aureus υπό συνθήκες µονο- και µεικτής καλλιέργειας σε υποθανάτιες συγκεντρώσεις χλωριούχου βενζαλκονίου , υπεροξικού οξέος και υποχλωριώδους νατρίου
Get PDFΣτην παρούσα µελέτη µελετήθηκε η ανθεκτικότητα βιο-υµενικών κυττάρων Salmonella Typhimurium (ST) και Staphylococcus aureus (SA) (3 στελέχη ανά είδος), όταν αυτά αφέθηκαν να σχηµατίσουν βιο-υµένια είτε σε συνθήκες µόνο ή µεικτής καλλιέργειας σε επιφάνεια ανοξείδωτου χάλυβα (SS), σε τρία διαφορετικά απολυµαντικά (χλωριούχο βενζαλκόνιο BC, υπεροξικό οξύ ΡΑ και υποχλωριώδες νατρίου SH). Τα αποτελέσµατα της µελέτης έδειξαν ότι οι συνθήκες µεικτής καλλιέργειας οδήγησαν σε µείωση του πληθυσµού των βιο-υµενικών κυττάρων (0.6 και 1.1 log cfu/cm2 για ST και SA, αντίστοιχα), σε σύγκριση µε τις συνθήκες µονο-καλλιέργειας. Φάνηκε ότι το BC ήταν το πιο αποτελεσµατικό απολυµαντικό στις δύο περιπτώσεις βιο-υµενικών κυττάρων. Το PA ήταν πιο αποτελεσµατικό στην απολύµανση ST βιο-υµενικών κυττάρων και στις δύο συνθήκες καλλιέργειας.
Ιn this study, the resistance of sessile cells of Salmonella Typhimurium (ST) and Staphylococcus aureus (SA) (3 strains per species), when these were left to form biofilms under either monoor dual-species conditions on a stainless steel surface, to 3 different disinfectants (benzalkonium chloride BC, paracetic acid PA and sodium hypochlorite SH) was investigated. Results showed that dual-species conditions seem to lead to a reduction in the number of sessile cells (0.6 and 1.1 log cfu/cm2 for ST and SA, respectively), compared to mono-species conditions. Regarding the disinfection resistance, in general BC was found to be more effective in both mono-and dual-species biofilm communities. PA was more effective against ST biofilm cells under both conditions
Adaptation of Streptococcus macedonicus and Streptococcus thermophilus in milk. Common strategies, distinct ways.
Get PDFLactic acid bacteria (LAB) are the most important bacteria in food fermentations. Among the genera included in LAB is the Streptococcus genus, containing a number of species that are commensals and opportunistic pathogens. Up to now only one species in the Streptococcus genus, Streptococcus thermophilus, has been traditionally used as a starter in milk and is considered a domesticated organism. However, Streptococcus macedonicus, belonging to the S. bovis/S. equinus complex (SBSEC), can be also found in milk. In this study, S. macedonicus was fully sequenced and a comparative analysis was performed against all other SBSEC members. According to our analysis, S. macedonicus missed several genes encoding enzymes for the degradation of complex plant carbohydrates typically met in the genome of Streptococcus gallolyticus, indicating a reduced ability to survive in the gastrointestinal tract of herbivores. In addition, two pilus operons necessary for the adhesion of S. gallolyticus to the host and the initiation of infection were absent from the S. macedonicus genome. Adaptation of S. macedonicus to the milk environment was supported by the presence of an extra lactose operon. Finally, the plasmid pSMA198 found in S. macedonicus also provided evidence about the habituation of the species to milk. Our findings support adaptation of S. macedonicus to the rich in nutrients milk environment characterized by diminished biosynthetic capabilities and loss of pathogenicity-related genes in parallel to gene gain events through horizontal gene transfer, similarly to S. thermophilus. Comparative analysis between S. macedonicus and S. thermophilus though revealed numerous species-specific differences at the genomic and proteomic level, suggesting that common strategies can be used by truly divergent organisms during their evolutionary histor
Isolation of GST isoenzymes from Phaseolus vulgaris L. and characterization of detoxifying mechanism under biotic and abiotic stress
Get PDFThree Glutathione transferase (GSTs) isoenzymes have been isolated from P. vulgaris leaves after in vivo treatment with 1/250 fluazifop-p-butyl herbicide. The inducible GST isoenzymes were identified and separated by affinity chromatography. They found to belong to phi and tau classes. Moreover, the fluazifop-inducible glutathione transferases from P. vulgaris (PvGSTs, termed PvGSTU2-2, PvGSTF1-1 and PvGSTU3-3) were found to catalyze a broad range of reactions and exhibit quite varied substrate specificity. Another GST isoenzyme was isolated from P. vulgaris (PvGST, termed PvGSTU3-3), after its induction with biotic stress treatment (Uromyces appendiculatus infection). PvGSTU3-3 shares high homology the tau class plant and catalyzes several different reactions and exhibits wide substrate specificity. Of particular importance are the high antioxidant catalytic function and hydroperoxidase, thioltransferase, and dehydroascorbate reductase action of Pv-GSTU3-3. Transgenic tobacco plants over-expressing PvGSTU2-2 isoenzyme have
been developed via Agrobacteriun tumefaciens in order to study their in planta potential to confer biotic and abiotic resistance as a means of plant breeding. Our results provide new insights into catalytic and structural diversity of GSTs and the detoxifying mechanism used by P. vulgaris. Moreover, highlight the functional and catalytic diversity of plant GSTs and demonstrate their pivotal role for addressing biotic stresses in P. vulgaris
Plant Glutathione Transferases: Structure, Antioxidant Catalytic Function and in planta Protective Role in Biotic and Abiotic Stress
Get PDFPlant cytosolic glutathione transferases (GSTs) belong to an ancient enzyme superfamily with multiple and diverse functions which are important in counteracting biotic and abiotic stress. GSTs catalyze the conjugation of xenobiotics and endogenous electrophilic compounds with glutathione (GSH), leading to their detoxification. GSTs not only catalyze detoxification reactions but they are also involved in GSH-dependent isomerization reactions, in GSH-dependent reduction of organic hydroperoxides, biosynthesis of secondary metabolites, and exhibit thioltransferase and dehydroascorbate reductase activity. The applications of ‘omics’ technologies have allowed the classification of GSTs and the study of their evolution and sequence diversity, while enzymology has provided powerful insights into their catalytic role. This review focuses on plant GSTs, and attempts to give an overview of the new insights into their catalytic function and biological role in biotic and abiotic stress tolerance mechanisms in plants
Stress-inducible GmGSTU4 shapes transgenic tobacco plants metabolome towards increased salinity tolerance
Get PDFThe involvement of glutathione transferases (GSTs) in plant’s tolerance to abiotic stresses has been extensively studied; however, the metabolic changes occurring in the plants with altered GSTs expression have not been studied in detail. We have previously demonstrated that GmGSTU4 overexpression in tobacco plants conferred increased tolerance to herbicides, partly through its peroxidase activity. Here, we investigated GmGSTU4 transcriptional response to abiotic and chemical stimuli in soybean. Transgenic tobacco plants overexpressing GmGSTU4 were also evaluated regarding their phenotypic and metabolomics responses under salt stress. GmGSTU4 expression was highly induced after salt stress and atrazine treatment. Tobacco plants overexpressing GmGSTU4 were highly tolerant to 150 mM NaCl in vitro. Metabolomics comparison of plants growing under optimal conditions, indicating a shift of the transgenic plants metabolism towards the metabolic profiles observed under stress, increased concentration of precursors of glutathione biosynthesis and hexose concentration reduction. Under salt stress, transgenic plants maintained their cellular homeostasis in contrast to wild-type plants which exhibited deregulated energy metabolism. The metabolic response of the transgenic plants was characterized by higher concentration of protective metabolites such as proline and trehalose and greater induction of the oxidative pentose phosphate pathway. These results confirm GmGSTU4 contribution to salt stress tolerance, and outline a regulatory role that primes plants towards the up-regulation of protective and detoxification mechanisms under abiotic stress
Tracking Single-Cells in Overcrowded Bacterial Colonies
Get PDFCell tracking enables data extraction from timelapse "cell movies" and promotes modeling biological processes at the single-cell level. We introduce a new fully automated computational strategy to track accurately cells across frames in time-lapse movies. Our method is based on a dynamic neighborhoods formation and matching approach, inspired by motion estimation algorithms for video compression. Moreover, it exploits "divide and conquer" opportunities to solve effectively the challenging cells tracking problem in overcrowded bacterial colonies. Using cell movies generated by different labs we demonstrate that the accuracy of the proposed method remains very high (exceeds 97%) even when analyzing large overcrowded microbial colonies