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51.
Peters JU Weber S Kritter S Weiss P Wallier A Boehringer M Hennig M Kuhn B Loeffler BM 《Bioorganic & medicinal chemistry letters》2004,14(6):1491-1493
The influence of aromatic substitution on a newly discovered class of inhibitors of dipeptidyl peptidase IV was investigated. A 10(5)-fold increase in potency was achieved by the optimization of aromatic substituents in a parallel chemistry program. The observed SAR could be explained by an X-ray structure of the protein-ligand complex. 相似文献
52.
Partially purified prostacyclin synthase from pig aorta converted the prostaglandin (PG) endoperoxide PGH2 to prostacyclin (PGI2), and PGH1 to 12-hydroxy-8,10-heptadecadienoic acid (HHD). Both reactions were inhibited by 15-hydroperoxy-5,8,11,13-eicosatetraenoic acid (15-HP) in a dose-dependent fashion. However, the reactions PGH2 → PGI2 and PGH1 → HHD appeared to differ: substrate availability was rate limiting in the latter reaction, while the enzyme became rapidly saturated with PGH2 and a steady rate of prostacyclin formation was observed at higher substrate levels. 相似文献
53.
Bobby G. Ng Paulina Sosicka François Fenaille Annie Harroche Sandrine Vuillaumier-Barrot Mindy Porterfield Zhi-Jie Xia Shannon Wagner Michael J. Bamshad Marie-Christine Vergnes-Boiteux Sophie Cholet Stephen Dalton Anne Dell Thierry Dupré Mathieu Fiore Stuart M. Haslam Yohann Huguenin Tadahiro Kumagai Hudson H. Freeze 《American journal of human genetics》2021,108(6):1040-1052
54.
The flacca tomato (Lycopersicon esculentum) mutant displays a wilty phenotype as a result of abscisic acid (ABA) deficiency. The Mo cofactor (MoCo)-containing aldehyde oxidases (AO; EC 1.2.3.1) are thought to play a role in the final oxidation step required for ABA biosynthesis. AO and related MoCo-containing enzymes xanthine dehydrogenase (XDH; EC 1.2.1.37) and nitrate reductase (EC 1.6.6.1) were examined in extracts of the flacca tomato genotype and of wild-type (WT) roots and shoots. The levels of MoCo were found to be similar in both genotypes. No significant XDH or AO (MoCo-containing hydroxylases) activities were detected in flacca leaves; however, the mutant exhibited considerable MoCo-containing hydroxylase activity in the roots, which contained notable amounts of ABA. Native western blots probed with an antibody to MoCo-containing hydroxylases revealed substantial, albeit reduced, levels of cross-reactive protein in the flacca mutant shoots and roots. The ABA xylem-loading rate was significantly lower than that in the WT, indicating that the flacca is also defective in ABA transport to the shoot. Significantly, in vitro sulfurylation with Na2S reactivated preexisting XDH and AO proteins in extracts from flacca, particularly from the shoots, and superinduced the basal-level activity in the WT extracts. The results indicate that in flacca, MoCo-sulfurylase activity is impaired in a tissue-dependent manner. 相似文献
55.
Maria Victoria Sanchez Thomas Ebensen Kai Schulze Diego Cargnelutti Paulina Blazejewska Eduardo A. Scodeller Carlos A. Guzmán 《PloS one》2014,9(8)
There is a critical need for new influenza vaccines able to protect against constantly emerging divergent virus strains. This will be sustained by the induction of vigorous cellular responses and humoral immunity capable of acting at the portal of entry of this pathogen. In this study we evaluate the protective efficacy of intranasal vaccination with recombinant influenza nucleoprotein (rNP) co-administrated with bis-(3′,5′)-cyclic dimeric adenosine monophosphate (c-di-AMP) as adjuvant. Immunization of BALB/c mice with two doses of the formulation stimulates high titers of NP-specific IgG in serum and secretory IgA at mucosal sites. This formulation also promotes a strong Th1 response characterized by high secretion of INF-γ and IL-2. The immune response elicited promotes efficient protection against virus challenge. These results suggest that c-di-AMP is a potent mucosal adjuvant which may significantly contribute towards the development of innovative mucosal vaccines against influenza. 相似文献
56.
Tom A. R. Price Amanda Bretman Ana C. Gradilla Julia Reger Michelle L. Taylor Paulina Giraldo-Perez Amy Campbell Gregory D. D. Hurst Nina Wedell 《Proceedings. Biological sciences / The Royal Society》2014,281(1783)
The extent of female multiple mating (polyandry) can strongly impact on the intensity of sexual selection, sexual conflict, and the evolution of cooperation and sociality. More subtly, polyandry may protect populations against intragenomic conflicts that result from the invasion of deleterious selfish genetic elements (SGEs). SGEs commonly impair sperm production, and so are likely to be unsuccessful in sperm competition, potentially reducing their transmission in polyandrous populations. Here, we test this prediction in nature. We demonstrate a heritable latitudinal cline in the degree of polyandry in the fruitfly Drosophila pseudoobscura across the USA, with northern population females remating more frequently in both the field and the laboratory. High remating was associated with low frequency of a sex-ratio-distorting meiotic driver in natural populations. In the laboratory, polyandry directly controls the frequency of the driver by undermining its transmission. Hence we suggest that the cline in polyandry represents an important contributor to the cline in sex ratio in nature. Furthermore, as the meiotic driver causes sex ratio bias, variation in polyandry may ultimately determine population sex ratio across the USA, a dramatic impact of female mating decisions. As SGEs are ubiquitous it is likely that the reduction of intragenomic conflict by polyandry is widespread. 相似文献
57.
Anastasia Chasapi Paulina Wachowicz Anne Niknejad Philippe Collin Andrea Krapp Elena Cano Viesturs Simanis Ioannis Xenarios 《PloS one》2015,10(8)
Cytokinesis in fission yeast is controlled by the Septation Initiation Network (SIN), a protein kinase signaling network using the spindle pole body as scaffold. In order to describe the qualitative behavior of the system and predict unknown mutant behaviors we decided to adopt a Boolean modeling approach. In this paper, we report the construction of an extended, Boolean model of the SIN, comprising most SIN components and regulators as individual, experimentally testable nodes. The model uses CDK activity levels as control nodes for the simulation of SIN related events in different stages of the cell cycle. The model was optimized using single knock-out experiments of known phenotypic effect as a training set, and was able to correctly predict a double knock-out test set. Moreover, the model has made in silico predictions that have been validated in vivo, providing new insights into the regulation and hierarchical organization of the SIN. 相似文献
58.
59.
Construction of a 'unigene' cDNA clone set by oligonucleotide fingerprinting allows access to 25 000 potential sugar beet genes 总被引:1,自引:0,他引:1
60.
Jakub Karczmarski Tymon Rubel Agnieszka Paziewska Michal Mikula Mateusz Bujko Paulina Kober Michal Dadlez Jerzy Ostrowski 《Clinical proteomics》2014,11(1):24