Synthesis of (di)nucleoside polyphosphates by the ubiquitin activating enzyme E1

Open Access.Previous work from this laboratory had shown that ligases may catalyze the synthesis of (di)nucleoside polyphosphates. Here, we show that one of the enzymes of the proteasome system (E1 or the ubiquitin (Ub) activating enzyme, EC 6.3.2.19) catalyzes very effectively (kcat = 0.29 ± 0.05 s-1) the transfer of AMP from the E-AMP-ubiquitin complex to tripolyphosphate or tetrapolyphosphate with formation of adenosine tetra- or pentaphosphate (p4A or p5A), respectively. Whereas the concomitant formation of AMP is stimulated by the presence of dithiothreitol in a concentration dependent manner, the synthesis of p4A is only slightly inhibited by this compound. Previous treatment of the enzyme (E1) with iodoacetamide inhibited only partially the synthesis of p4A. p 4A can substitute for ATP as substrate of the reaction to generate the ubiquityl adenylate complex. A small amount of diadenosine pentaphosphate (Ap5A) was also synthesized in the presence of p4A. © 2005 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.This investigation was supported by grants from Dirección General de Investigación Científica y Técnica (BMC-2002-00866) and Instituto de Salud Carlos III, RMN (C03/08).Peer Reviewe

Impact on soil degradation factors of changes in rain intensity patterns in southern Spain

In southern of Spain, the torrential nature of the rainfalls alters the soil water availability for vegetation and, consequently, its spatially and temporally pattern. This fact, combined with the current global warming, raises a modification of the eco-geomorphological processes dynamics in Mediterranean areas

The geomorphological rainfall in the Mediterranean landscape modeling

The kinetic energy derived from the heavy rainfall constitutes one of the main factors of the geomorphological processes in Mediterranean environments, as well as in the landscape and the ecosystem modeling, resulting from its extraordinary spatial and temporal variability. When the rainfall is analyzed, particularly in Mediterranean climate and in the context of Climate Change, it is not only necessary to consider the total rainfall collected annually, but also it is essential to take into account other variables as intensity, duration, and frequency. A series of extreme rainfall databases have been analyzed for the last 25 years (1993-2017), with daily, horary and 10-minutes registers. These have been obtained from different weather stations belonging to the Agencia Estatal de Meteorología –AEMET- and the S.A.I.H. Hydrosur Network, spatially distributed in two regions of the province of Malaga. (Guadalhorce and Axarquía). The results show the limited frequency of the events considered as torrential rainfall according to the Agencia Estatal de Meteorología criteria ( 100mm/24h; 60mm/60’) and a high occurrence of shorts heavy downpours ( 10mm/10’), especially in recent years. These downpours have been classified as “geomorphological rainfall”, short events capable of activating hydro-soil processes, owing to its high intensity and the vulnerable conditions of the eco-geomorphological system in the study areas

Synthesis of bisphosphonate derivatives of ATP by T4 RNA ligase

AbstractT4 RNA ligase catalyzes the synthesis of ATP β,γ-bisphosphonate analogues, using the following substrates with the relative velocity rates indicated between brackets: methylenebisphosphonate (pCH2p) (100), clodronate (pCCl2p) (52), and etidronate (pC(OH)(CH3)p) (4). The presence of pyrophosphatase about doubled the rate of these syntheses. Pamidronate (pC(OH)(CH2–CH2–NH2)p), and alendronate (pC(OH)(CH2–CH2–CH2–NH2)p) were not substrates of the reaction. Clodronate displaced the AMP moiety of the complex E-AMP in a concentration dependent manner. The Km values and the rate of synthesis (kcat) determined for the bisphosphonates as substrates of the reaction were, respectively: methylenebisphosphonate, 0.26±0.05mM (0.28±0.05s−1); clodronate, 0.54±0.14mM (0.29±0.05s−1); and etidronate, 4.3±0.5mM (0.028±0.013s−1). In the presence of GTP, and ATP or AppCCl2p the relative rate of synthesis of adenosine 5′,5‴-P1,P4-tetraphosphoguanosine (Ap4G) was around 100% and 33%, respectively; the methylenebisphosphonate derivative of ATP (AppCH2p) was a very poor substrate for the synthesis of Ap4G. To our knowledge this report describes, for the first time, the synthesis of ATP β,γ-bisphosphonate analogues by an enzyme different to the classically considered aminoacyl-tRNA synthetases

Analysis of heavy rainfall in two contrasted Mediterranean watersheds from 1993 to 2017

"Despite the proximity of the watersheds there are strong" "environmental contrasts between both." "• The current rainfall dynamics follows a trend towards concentration in fewer days." "• A rainfall cataloged as torrential by the AEMET (≥ 100 / 24h, ≥60 mmh-1) is not necessary to activate erosion and degradation processes, especially when the system conditions are vulnerable. There are downpours hidden in the hourly precipitation data that get at very high intensities." "• It is considered the need to analyze exhaustively the characteristics of a given system, in order to establish what capacity of response has a specific area in an event of extreme precipitation.

Nature-based solutions to address water threats in the Mediterranean region. A characterisation of the GIAHS area of Axarquia (Málaga, Spain)

The research has focused on a traditionally agricultural territory that is highly fragile to these processes, namely GIAHS dedicated to the raisin production in the Axarquia. The objective has been to (i) assess the impact of the most important water risks and (ii )identify the main NbS implemented as adaptive mechanisms that have been implemented to ensure food security and the sustainability of these areas. To achieve these objectives, the rainfall dynamics have been statistically analysed with the data downloaded from nine meteorological stations located in the region. In addition, a total of 60 soil samples have been collected and analysed for the estimation of soil water erosion rates, based on the RUSLE model, and for the evaluation of its hydrological dynamics in recent decades. Finally, the NbS identified in the study area have been qualitatively assessed and analysed from an ecosystemic and agricultural approach. The results show an increased water stress in this area according to the projections published by the latest IPCC report for this region. A slight tendency to concentration and increased rainfall erosivity is detected, as well as a lower water availability in soil for crop phenology. Soil erosion rates show very high values. However, agricultural practices and the different structures identified have been determinant in the control of these natural risks, being considered as sustainable adaptation strategies and conforming as NbS.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Effect of Bisphosphonates on Root Growth and on Chlorophyll Formation in Arabidopsis thaliana Seedlings

Capítulo 41.-- Open Access: License CC BY 3.0This work was supported by grants from the Spanish National Plan for Research, Development and Innovation (BFU 2008-00666/BMC, BFU 2009-08977 and AYA2009- 07952).Peer Reviewe

Pros and cons of olive fertigation: Influence on fruit and oil quality

Agronomic practices can modify olive fruit and oil quality. However, there is little information on the influence of fertigation, a common practice in most intensive orchards. We studied nutrient distribution in the soil profile following fertigation with different doses of N-P-K fertilizer, and its effect on nutrient concentrations, yield and both table olive and oil quality. Measurements were performed in an adult 'Manzanilla de Sevilla' olive orchard in which 100, 200 and 400 g N per tree and irrigation period of a 4N-1P-3K fertilizer were applied by fertigation from 1999 to 2001 (three growing seasons) and 200, 400 and 600 g N of the same fertilizer were applied in the two following growing seasons (2002-2003). A control treatment, irrigation without fertilizer, was also established. Irrigation amounts were similar in all treatments. In 2003, NO3-N, P and K concentrations in the root zone wetted by irrigation were studied: they increased with respect to those in the drying zone, showing a general linear relationship with fertilizer dose, particularly in the top soil layer where most of the olive roots were active. In the 600 g N treatment, leaching losses were observed at 0.8-0.9 m depth, possibly leading to groundwater contamination. We found an increase in fruit yield with increasing fertilizer dose, likely due to the observed greater concentrations of NO3-N, P and K in the soil. In fact, our data show a positive relationship between increased soil NO3-N, P and K availability and higher leaf N, P, K concentrations. This could have accounted for the observed increase in canopy volume, fruit number per tree and fruit weight with the amount of fertilizer. Despite the fact that fruit weight, pulp/stone ratio and volume increased with fertilizer dose, reducing sugars, necessary for olive fermentation, and pulp texture decreased. Differences in texture remained after 'Spanish-style' green olive processing. In addition, no differences were found in oil content but its quality was negatively affected with increasing fertilizer: in particular, polyphenol total content, bitterness, oxidative stability and the relation of monounsaturated/polyunsaturated fatty acids decreased with fertilizer dose

Diferenciar entre el televidente frecuente de fútbol (TFF) y el televidente ocasional de fútbol (TOF) peruano, para mejorar el modelo tradicional de valorización del costo de los auspicios publicitarios

El valor que los anunciantes pagan por auspiciar un partido de fútbol se basa principalmente en la variable “nivel de audiencia” —denominada “televidentes”— que logran dichos partidos durante su transmisión. Es decir, a mayor número de televidentes, mayor es el valor que los anunciantes y sus marcas encuentran y pagan por este tipo de auspicios publicitarios. Esta investigación plantea, desde un enfoque cuantitativo, diferenciar a estos televidentes en dos clases distintas según su comportamiento y su nivel de involucramiento con la transmisión deportiva: los televidentes ocasionales y los televidentes frecuentes. Mediante esta diferenciación, se busca encontrar y profundizar en un aspecto clave del modelo tradicional que se usa actualmente para determinar el valor de un auspicio de fútbol en televisión de paga, con el fin de cuestionarlo y mejorarlo.The value that advertisers pay to sponsor a soccer game is mainly based on the “audience” variable —also called “viewers”— that these games achieve during their broadcasting. That means that the more viewersthere are, the highest the value advertisers and their brands find and pay for this type of advertising sponsorship. This research uses a quantitative approach to differentiate these viewers in two classes according to their behavior and level of involvement with sports broadcasting: occasional viewers and frequent viewers. With this differentiation, this research seeks to find and deepen on a key aspect of the current traditional model used to determine the value of soccer sponsorship on pay television, in order to question and improve it.Tesi