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DNA double-strand breaks (DSBs) are deleterious lesions that challenge genome integrity. To mitigate this threat, human cells rely on the activity of multiple DNA repair machineries that are tightly regulated throughout the cell cycle1. In interphase, DSBs are mainly repaired by non-homologous end joining and homologous recombination2. However, these pathways are completely inhibited in mitosis3–5, leaving the fate of mitotic DSBs unknown. Here we show that DNA polymerase theta6(Polθ) repairs mitotic DSBs and thereby maintains genome integrity. In contrast to other DSB repair factors, Polθ function is activated in mitosis upon phosphorylation by Polo-like kinase 1 (PLK1). Phosphorylated Polθ is recruited by a direct interaction with the BRCA1 C-terminal domains of TOPBP1 to mitotic DSBs, where it mediates joining of broken DNA ends. Loss of Polθ leads to defective repair of mitotic DSBs, resulting in a loss of genome integrity. This is further exacerbated in cells that are deficient in homologous recombination, where loss of mitotic DSB repair by Polθ results in cell death. Our results identify mitotic DSB repair as the underlying cause of synthetic lethality between Polθ and homologous recombination. Together, our findings reveal the critical importance of mitotic DSB repair in the maintenance of genome integrity.

The evaluation of connections between the functional parameters of hydraulic systems and the quality indicators of water, depending on time is obtained with the help of an original automatic calculation program, elaborated by authors. The original automatic calculation program defines the exploitations regimes for the overall outputs installation to be maximum, the total typical energy consumed to be minimum on the work cycle ensemble and the water quality to be according to international settlements. Follow the variation in hydraulic slope water transport channel, the variation between the weir and hydraulic ram level variation. The water depth studies the variation in drainage canal in biological stage.

The pumps are mechanical structures indispensable in numerous socio-economic areas like: villages water supply, irrigations, oil industry, sewage movement, chemical movement, flood control and for the production of various goods. Pumps must supply the energy necessary to lift liquids from a lower elevation to a greater one. Pumps operation and maintenance generates significant costs. One of the most efficient methods to reduce the pump operating costs is by scheduling the pump operations. This can impose pumps to operate during periods in which the electrical tariff is cheaper and combining the operations of several pumps in an efficient way. This paper aims to analyze the possibilities and the limits of using SPEA2 multi-objective optimization algorithm implemented in Matlab in order to schedule the pumps. SPEA2 was used for the first time to schedule the pumps from a water supply system by [. In that paper the algorithm was applied in Linux. This paper presents the results obtained by SPEA2 implemented in a very used programming language, Matlab. The algorithm was improved in order to obtain better solutions. In this paper we applied the optimization methods of the pump schedule to a water supply system, but these methods can be used to minimize the operational costs of any system that incorporates pumps.

This paper aims to analyze the connections between the functional parameters of pumping station and the quality parameters of drinkable water: 1) The connections estimation between the pumps head, flow and the waters turbulence. 2) The values analyze of chlorine and ammonium concentration depending on flow. 3) The water conductivity analyzes depending on flow.

Small and large scale proteomic technologies are providing a wealth of potential interactions between proteins bearing phospho-recognition modules and their substrates. Resulting interaction maps reveal such a dense network of interactions that the functional dissection and understanding of these networks often require to break specific interactions while keeping the rest intact. Here, we developed a computational strategy, called STRIP, to predict the precise interaction site involved in an interaction with a phospho-recognition module. The method was validated by a two-hybrid screen carried out using the ForkHead Associated (FHA)1 domain of Rad53, a key protein of Saccharomyces cerevisiae DNA checkpoint, as a bait. In this screen we detected 11 partners, including Cdc7 and Cdc45, essential components of the DNA replication machinery. FHA domains are phospho-threonine binding modules and the threonines involved in both interactions could be predicted using the STRIP strategy. The threonines T484 and T189 in Cdc7 and Cdc45, respectively, were mutated and loss of binding could be monitored experimentally with the full-length proteins. The method was further tested for the analysis of 63 known Rad53 binding partners and provided several key insights regarding the threonines likely involved in these interactions. The STRIP method relies on a combination of conservation, phosphorylation likelihood, and binding specificity criteria and can be accessed via a web interface at http://biodev.extra.cea.fr/strip/.

Small and large scale proteomic technologies are providing a wealth of potential interactions between proteins bearing phospho-recognition modules and their substrates. Resulting interaction maps reveal such a dense network of interactions that the functional dissection and understanding of these networks often require to break specific interactions while keeping the rest intact. Here, we developed a computational strategy, called STRIP, to predict the precise interaction site involved in an interaction with a phospho-recognition module. The method was validated by a two-hybrid screen carried out using the ForkHead Associated (FHA)1 domain of Rad53, a key protein of Saccharomyces cerevisiaeDNA checkpoint, as a bait. In this screen we detected 11 partners, including Cdc7 and Cdc45, essential components of the DNA replication machinery. FHA domains are phospho-threonine binding modules and the threonines involved in both interactions could be predicted using the STRIP strategy. The threonines T484 and T189 in Cdc7 and Cdc45, respectively, were mutated and loss of binding could be monitored experimentally with the full-length proteins. The method was further tested for the analysis of 63 known Rad53 binding partners and provided several key insights regarding the threonines likely involved in these interactions. The STRIP method relies on a combination of conservation, phosphorylation likelihood, and binding specificity criteria and can be accessed via a web interface at http://biodev.extra.cea.fr/strip/.

Polyoxometalates POMs show promising antibacterial, antiviral particularly antiHIV, antitumor, and anticancer activities, but the mechanism of these potential therapeutic effects remains to be elucidated at the molecular level. The interaction between the Gdcontaining tungstosilicate [Gdβ2SiW11O392]13–and human serum albumin HSA was studied by several techniques. Fluorescence spectroscopy showed an energy transfer between the single tryptophan residue of HSA and the POM. Circular dichroism led to the conclusion that the POM significantly altered the secondary structure of HSA. Isothermal titration calorimetry revealed an enthalpydriven binding reaction between HSA and the POM, resulting in the formation of a 1:1 complex.© WileyVCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009

Calbindin D28kis a member of the calmodulin superfamily of Ca2+-binding proteins and contains six EF-hands. The protein is generally believed to function as a Ca2+buffer, but the studies presented in this work indicate that it may also act as a Ca2+sensor. The results show that Mg2+binds to the same sites as Ca2+with an association constant of ∼1.4·103m−1in 0.15 mKCl. The four high affinity sites in calbindin D28kbind Ca2+in a non-sequential, parallel manner. In the presence of physiological concentrations of Mg2+, the Ca2+affinity is reduced by a factor of 2, and the cooperativity, which otherwise is modest, increases. Based on the binding constants determined in the presence of physiological salt concentrations, we estimate that at the Ca2+concentration in a resting cell calbindin D28kis saturated to 40–75% with Mg2+but to less than 9% with Ca2+. In contrast, the protein is expected to be nearly fully saturated with Ca2+at the Ca2+level of an activated cell. A substantial conformational change is observed upon Ca2+binding, but only minor structural changes take place upon Mg2+binding. This suggests that calbindin D28kundergoes Ca2+-induced structural changes upon Ca2+activation of a cell. Thus, calbindin D28kdisplays several properties that would be expected for a protein involved in Ca2+-induced signal transmission and hence may function not only as a Ca2+buffer but also as a Ca2+sensor. Digestion patterns resulting from limited proteolysis of the protein suggest that the loop of EF-hand 2, a variant site that does not bind Ca2+, becomes exposed upon Ca2+binding.

The adkgene from Mycobacterium tuberculosiscodes for an enzyme of 181 amino acids. A sequence comparison with 52 different forms of adenylate kinases (AK) suggests that the enzyme from M. tuberculosisbelongs to a new subfamily of “short” bacterial AKs. The recombinant protein, overexpressed in Escherichia coli, exhibits a low catalytic activity and an unexpectedly high thermal stability (Tm = 64.8°C). Based on various spectroscopic data, on the known three‐dimensional structure of the AK from E. coliand on secondary structure predictions for various sequenced AKs, we propose a structural model for AK from M. tuberculosis(AKmt). Proteins 1999;36:238–248. © 1999 Wiley‐Liss, Inc.

The adk gene from Mycobacterium tuberculosis codes for an enzyme of 181 amino acids. A sequence comparison with 52 different forms of adenylate kinases (AK) suggests that the enzyme from M. tuberculosis belongs to a new subfamily of “short” bacterial AKs. The recombinant protein, overexpressed in Escherichia coli, exhibits a low catalytic activity and an unexpectedly high thermal stability (Tm = 64.8°C). Based on various spectroscopic data, on the known three-dimensional structure of the AK from E. coli and on secondary structure predictions for various sequenced AKs, we propose a structural model for AK from M. tuberculosis (AKmt). Proteins 1999;36:238–248. © 1999 Wiley-Liss, Inc.