A bacterial field isolate recovered from infected tomato plants in a green-house at Sidi Rehal, a region near Casablanca city (Morocco), was identified as the gammaproteobacterium Pseudomonas syringae pv. tomato DC300...A bacterial field isolate recovered from infected tomato plants in a green-house at Sidi Rehal, a region near Casablanca city (Morocco), was identified as the gammaproteobacterium Pseudomonas syringae pv. tomato DC3000 strain, the causal agent of bacterial speck. The bacterial isolate was characterized by morphological, biochemical and molecular biological tests, its growth curves carried out in various culture media, and its phytopathogenicity verified by infection tests. A screening was performed to evaluate the antibacterial activity of methanolic extracts of 12 selected Moroccan plants against the P. syringae pv. tomato DC3000 isolate, and Agar-well diffusion and Broth microdilution methods were used to determine minimum inhibitory and minimum bactericidal concentrations. Among the methanolic extracts tested, only those of Nigella sativa, Geranuim robertianum, Aizoon canariense and Rubia peregrine showed clear inhibitory and bactericidal activities, although the highest values were achieved with N. sativa, a plant used in Morocco as a spice, condiment and medicinal treatment.展开更多
According to molecular biology, genomic and proteomic data, the phytopathogenic gamma-proteobacterium Pseudomonas syringae pv. tomato DC3000 produces a number of proteins that may promote infection and draw nutrients ...According to molecular biology, genomic and proteomic data, the phytopathogenic gamma-proteobacterium Pseudomonas syringae pv. tomato DC3000 produces a number of proteins that may promote infection and draw nutrients from plants. Remarkably, P. syringae DC3000 strain possesses three paralogous gap genes encoding glyceraldehyde-3-phosphate dehydrogenase (GAPDH) enzymes with different predicted molecular sizes and metabolic functions. As GAPDH was shown to be a virulence factor in other microbial pathogens, in the current study, we analyzed the expression levels of each paralogous gap gene by realtime PCR to understand the actual impact of their protein products on P. syringae virulence. We found that all of them were strongly induced during the infection process. Nevertheless, proteomic analysis of culture supernatants revealed that only Class I GAPDH1 encoded by the gap1 gene was identified as an extracellular protein in infective cells. These results strongly suggest that this GAPDH should play a role in the infective process, including its well-know enzymatic function in the glycolytic metabolic pathway.展开更多
W Tumor proliferation of cancer cells requires a high intake of oxygen by angiogenesis. Deep cancer cells suffer from asphyxia and meet their energy needs through the enzymes of glycolysis. The anti-angio- genesis app...W Tumor proliferation of cancer cells requires a high intake of oxygen by angiogenesis. Deep cancer cells suffer from asphyxia and meet their energy needs through the enzymes of glycolysis. The anti-angio- genesis approach has been recognized for therapeutic purposes, but the deep cancers, difficult to reach by this therapy, could be targeted by inhibiting an enzyme of the glycolytic cycle. Our work focused on the study of the expression of GAPDH, a key enzyme of glycolysis, in cervix, breast and prostate tumors, for two approaches: Fundamental and targeted therapeutics. 60 samples, taken at the Anatomopathology laboratory of the Pasteur Institute of Morocco, were examined histologically and immunohistochemically, demonstrating the expression and cellular localization of GAPDH. The three organs have shown an overex-pression of GAPDH in tumor tissues. At the cellular level, the localization of GAPDH in cancer tissue is diffuse but mostly nuclear whereas it remains focused at the membrane and/or the cytoplasm in benign tumor tissues. From these results we could assume that GAPDH is involved in the cancer process and draws attention to a possible new nuclear role that could be either specific to one form or different isoforms of GAPDH enzyme.展开更多
文摘A bacterial field isolate recovered from infected tomato plants in a green-house at Sidi Rehal, a region near Casablanca city (Morocco), was identified as the gammaproteobacterium Pseudomonas syringae pv. tomato DC3000 strain, the causal agent of bacterial speck. The bacterial isolate was characterized by morphological, biochemical and molecular biological tests, its growth curves carried out in various culture media, and its phytopathogenicity verified by infection tests. A screening was performed to evaluate the antibacterial activity of methanolic extracts of 12 selected Moroccan plants against the P. syringae pv. tomato DC3000 isolate, and Agar-well diffusion and Broth microdilution methods were used to determine minimum inhibitory and minimum bactericidal concentrations. Among the methanolic extracts tested, only those of Nigella sativa, Geranuim robertianum, Aizoon canariense and Rubia peregrine showed clear inhibitory and bactericidal activities, although the highest values were achieved with N. sativa, a plant used in Morocco as a spice, condiment and medicinal treatment.
文摘According to molecular biology, genomic and proteomic data, the phytopathogenic gamma-proteobacterium Pseudomonas syringae pv. tomato DC3000 produces a number of proteins that may promote infection and draw nutrients from plants. Remarkably, P. syringae DC3000 strain possesses three paralogous gap genes encoding glyceraldehyde-3-phosphate dehydrogenase (GAPDH) enzymes with different predicted molecular sizes and metabolic functions. As GAPDH was shown to be a virulence factor in other microbial pathogens, in the current study, we analyzed the expression levels of each paralogous gap gene by realtime PCR to understand the actual impact of their protein products on P. syringae virulence. We found that all of them were strongly induced during the infection process. Nevertheless, proteomic analysis of culture supernatants revealed that only Class I GAPDH1 encoded by the gap1 gene was identified as an extracellular protein in infective cells. These results strongly suggest that this GAPDH should play a role in the infective process, including its well-know enzymatic function in the glycolytic metabolic pathway.
文摘W Tumor proliferation of cancer cells requires a high intake of oxygen by angiogenesis. Deep cancer cells suffer from asphyxia and meet their energy needs through the enzymes of glycolysis. The anti-angio- genesis approach has been recognized for therapeutic purposes, but the deep cancers, difficult to reach by this therapy, could be targeted by inhibiting an enzyme of the glycolytic cycle. Our work focused on the study of the expression of GAPDH, a key enzyme of glycolysis, in cervix, breast and prostate tumors, for two approaches: Fundamental and targeted therapeutics. 60 samples, taken at the Anatomopathology laboratory of the Pasteur Institute of Morocco, were examined histologically and immunohistochemically, demonstrating the expression and cellular localization of GAPDH. The three organs have shown an overex-pression of GAPDH in tumor tissues. At the cellular level, the localization of GAPDH in cancer tissue is diffuse but mostly nuclear whereas it remains focused at the membrane and/or the cytoplasm in benign tumor tissues. From these results we could assume that GAPDH is involved in the cancer process and draws attention to a possible new nuclear role that could be either specific to one form or different isoforms of GAPDH enzyme.
