An extracellular ␤-fructofuranosidase from the yeast Xanthophyllomyces dendrorhous was characterized biochemically, molecularly, and phylogenetically. This enzyme is a glycoprotein with an estimated molecular mass of 160 kDa, of which the N-linked carbohydrate accounts for 60% of the total mass. It displays optimum activity at pH 5.0 to 6.5, and its thermophilicity (with maximum activity at 65 to 70°C) and thermostability (with a T 50 in the range 66 to 71°C) is higher than that exhibited by most yeast invertases. The enzyme was able to hydrolyze fructosyl-␤-(231)-linked carbohydrates such as sucrose, 1-kestose, or nystose, although its catalytic efficiency, defined by the k cat /K m ratio, indicates that it hydrolyzes sucrose approximately 4.2 times more efficiently than 1-kestose. Unlike other microbial ␤-fructofuranosidases, the enzyme from X. dendrorhous produces neokestose as the main transglycosylation product, a potentially novel bifidogenic trisaccharide. Using a 41% (wt/vol) sucrose solution, the maximum fructooligosaccharide concentration reached was 65.9 g liter ؊1. In addition, we isolated and sequenced the X. dendrorhous ␤-fructofuranosidase gene (Xd-INV), showing that it encodes a putative mature polypeptide of 595 amino acids and that it shares significant identity with other fungal, yeast, and plant ␤-fructofuranosidases, all members of family 32 of the glycosyl-hydrolases. We demonstrate that the Xd-INV could functionally complement the suc2 mutation of Saccharomyces cerevisiae and, finally, a structural model of the new enzyme based on the homologous invertase from Arabidopsis thaliana has also been obtained.

Different types of floods are frequently causing important economic and personal damages in a variety of locations within Navarre, a region located in northern Spain. Navarre is found very close to the Cantabrian sea, but only about ten percent of its area belongs to that basin, whereas ninety percent of the region belongs to the -Ebro river watershed -Mediterranean basin. Ranging from very humid oceanic climate areas to semi-deserted locations in the south of the region, floods can be caused by persistent winter fronts coming from the Atlantic ocean to very intense convective summer storm events originated in the Iberic mountain range, located to the south of Navarre. The NAdapta Life project includes actions that focus on the mitigation of flood damages. Specifically, the drafting of local emergency plans for small and medium size towns in Navarre is described here. In order to facilitate the flood emergency episodes management, computer tools have been developed for each village selected for the project. Specific websites and smartphone applications have been implemented for each local entity. Awareness, diffusion and training sessions have been carried out along with the implementation of 'drafting and tools' plans.