Cerato-platanin (CP) is a secretion protein produced by the fungal pathogen Ceratocystis platani, the causal agent of the plane canker disease and the first member of the CP family. CP is considered a pathogen-associated molecular pattern because it induces various defense responses in the host, including production of phytoalexins and cell death. Although much is known about the properties of CP and related proteins as elicitors of plant defense mechanisms, its biochemical activity and host target(s) remain elusive. Here, we present the three-dimensional structure of CP. The protein, which exhibits a remarkable pH and thermal stability, has a double ψβ-barrel fold quite similar to those found in expansins, endoglucanases, and the plant defense protein barwin. Interestingly, although CP lacks lytic activity against a variety of carbohydrates, it binds oligosaccharides. We identified the CP region responsible for binding as a shallow surface located at one side of the β-barrel. Chemical shift perturbation of the protein amide protons, induced by oligo-N-acetylglucosamines of various size, showed that all the residues involved in oligosaccharide binding are conserved among the members of the CP family. Overall, the results suggest that CP might be involved in polysaccharide recognition and that the double ψβ-barrel fold is widespread in distantly related organisms, where it is often involved in host-microbe interactions.
Saliva samples of seventeen soccer players were analyzed by nuclear magnetic resonance before and after an official match. Two different ways of normalizing data are discussed, using total proteins and total metabolite concentrations. Changes in markers related to energy, hydration status, amino acids and other compounds were found. The limits and advantages of using saliva to define the systemic responses to exercise are examined, both in terms of data normalization and interpretation, and the time that the effect lasts in this biofluid, which is shorter to that commonly observed in blood. The heterogeneous nature and different timing of the exercise developed by players also plays an important role in the metabolic changes that can be measured. Our work focuses mainly on three different aspects: The effect that time sampling has on the observed effect, the type of normalization that is necessary to perform in order to cope with changes in water content, and the metabolic response that can be observed using saliva.
Urothelial bladder cancer (UBC) is the most common tumor of the urinary system. One of the biggest problems related to this disease is the lack of markers that can anticipate the progression of the cancer. Genomics and transcriptomics have greatly improved the prediction of risk of recurrence and progression. Further progress can be expected including information from other omics sciences such as metabolomics. In this study, we used 1H-NMR to characterize the intake of nutrients and the excretion of products in the extracellular medium of three UBC cell lines, which are representatives of low-grade tumors, RT4, high-grade, 5637, and a cell line that shares genotypic features with both, RT112. We have observed that RT4 cells show an activated oxidative phosphorylation, 5637 cells depend mostly on glycolysis to grow, while RT112 cells show a mixed metabolic state. Our results reveal the relative importance of glycolysis and oxidative phosphorylation in the growth and maintenance of different UBC cell lines, and the relationship with their genomic signatures. They suggest that cell lines associated with a low risk of progression present an activated oxidative metabolic state, while those associated with a high risk present a non-oxidative state and high glycolytic activity.