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771.
LuTHy: a double‐readout bioluminescence‐based two‐hybrid technology for quantitative mapping of protein–protein interactions in mammalian cells 下载免费PDF全文
Philipp Trepte Sabrina Kruse Simona Kostova Sheila Hoffmann Alexander Buntru Anne Tempelmeier Christopher Secker Lisa Diez Aline Schulz Konrad Klockmeier Martina Zenkner Sabrina Golusik Kirstin Rau Sigrid Schnoegl Craig C Garner Erich E Wanker 《Molecular systems biology》2018,14(7)
Information on protein–protein interactions (PPIs) is of critical importance for studying complex biological systems and developing therapeutic strategies. Here, we present a double‐readout bioluminescence‐based two‐hybrid technology, termed LuTHy, which provides two quantitative scores in one experimental procedure when testing binary interactions. PPIs are first monitored in cells by quantification of bioluminescence resonance energy transfer (BRET) and, following cell lysis, are again quantitatively assessed by luminescence‐based co‐precipitation (LuC). The double‐readout procedure detects interactions with higher sensitivity than traditional single‐readout methods and is broadly applicable, for example, for detecting the effects of small molecules or disease‐causing mutations on PPIs. Applying LuTHy in a focused screen, we identified 42 interactions for the presynaptic chaperone CSPα, causative to adult‐onset neuronal ceroid lipofuscinosis (ANCL), a progressive neurodegenerative disease. Nearly 50% of PPIs were found to be affected when studying the effect of the disease‐causing missense mutations L115R and ?L116 in CSPα with LuTHy. Our study presents a robust, sensitive research tool with high utility for investigating the molecular mechanisms by which disease‐associated mutations impair protein activity in biological systems. 相似文献
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Hagai Levine Hideo Mohri Anders Ekbom Liliana Ramos Geoff Parker Eduardo Roldan Luca Jovine Sabine Koelle Anna Lindstrand Simone Immler Sharon Mortimer David Mortimer Gerhard van der Horst Sumio Ishijima Natalie Aneck-Hahn Elisabetta Baldi Roelof Menkveld Susan A Rothmann Aleksander Giwercman Yvonne Giwercman Mats Holmberg Ulrik Kvist Lars Björndahl Rebecka Holmberg Stefan Arver John Flanagan Joël R Drevet 《Andrologie》2018,28(1):13
On the occasion of the XIIIth International Symposium on Spermatology held from 9 to 13 May 2018 in Stockholm (Sweden), participants (guest speakers and audience) collectively felt the need to make a public statement on the general issue of male reproductive health. Our intention is to raise awareness of what we believe is a neglected area of research despite alarming situations around the world. The disclosure strategy desired by the co-authors is to bring it to the attention of the greatest number partly by considering co-publication in the various periodicals dealing with Reproductive Biology and Andrology. BaCA’s editorial office accepted this mission and found it natural that our periodical, the official journal of the French Andrology Society (SALF), should carry this message. 相似文献
774.
Contribution of crop model structure,parameters and climate projections to uncertainty in climate change impact assessments 总被引:2,自引:0,他引:2 下载免费PDF全文
Fulu Tao Reimund P. Rötter Taru Palosuo Carlos Gregorio Hernández Díaz‐Ambrona M. Inés Mínguez Mikhail A. Semenov Kurt Christian Kersebaum Claas Nendel Xenia Specka Holger Hoffmann Frank Ewert Anaelle Dambreville Pierre Martre Lucía Rodríguez Margarita Ruiz‐Ramos Thomas Gaiser Jukka G. Höhn Tapio Salo Roberto Ferrise Marco Bindi Davide Cammarano Alan H. Schulman 《Global Change Biology》2018,24(3):1291-1307
Climate change impact assessments are plagued with uncertainties from many sources, such as climate projections or the inadequacies in structure and parameters of the impact model. Previous studies tried to account for the uncertainty from one or two of these. Here, we developed a triple‐ensemble probabilistic assessment using seven crop models, multiple sets of model parameters and eight contrasting climate projections together to comprehensively account for uncertainties from these three important sources. We demonstrated the approach in assessing climate change impact on barley growth and yield at Jokioinen, Finland in the Boreal climatic zone and Lleida, Spain in the Mediterranean climatic zone, for the 2050s. We further quantified and compared the contribution of crop model structure, crop model parameters and climate projections to the total variance of ensemble output using Analysis of Variance (ANOVA). Based on the triple‐ensemble probabilistic assessment, the median of simulated yield change was ?4% and +16%, and the probability of decreasing yield was 63% and 31% in the 2050s, at Jokioinen and Lleida, respectively, relative to 1981–2010. The contribution of crop model structure to the total variance of ensemble output was larger than that from downscaled climate projections and model parameters. The relative contribution of crop model parameters and downscaled climate projections to the total variance of ensemble output varied greatly among the seven crop models and between the two sites. The contribution of downscaled climate projections was on average larger than that of crop model parameters. This information on the uncertainty from different sources can be quite useful for model users to decide where to put the most effort when preparing or choosing models or parameters for impact analyses. We concluded that the triple‐ensemble probabilistic approach that accounts for the uncertainties from multiple important sources provide more comprehensive information for quantifying uncertainties in climate change impact assessments as compared to the conventional approaches that are deterministic or only account for the uncertainties from one or two of the uncertainty sources. 相似文献
775.
Environmental change and predator diversity drive alpha and beta diversity in freshwater macro and microorganisms 下载免费PDF全文
Pablo Augusto P. Antiqueira Owen L. Petchey Viviane Piccin dos Santos Valéria Maia de Oliveira Gustavo Quevedo Romero 《Global Change Biology》2018,24(8):3715-3728
Global biodiversity is eroding due to anthropogenic causes, such as climate change, habitat loss, and trophic simplification of biological communities. Most studies address only isolated causes within a single group of organisms; however, biological groups of different trophic levels may respond in particular ways to different environmental impacts. Our study used natural microcosms to investigate the predicted individual and interactive effects of warming, changes in top predator diversity, and habitat size on the alpha and beta diversity of macrofauna, microfauna, and bacteria. Alpha diversity (i.e., richness within each bromeliad) generally explained a larger proportion of the gamma diversity (partitioned in alpha and beta diversity). Overall, dissimilarity between communities occurred due to species turnover and not species loss (nestedness). Nevertheless, the three biological groups responded differently to each environmental stressor. Microfauna were the most sensitive group, with alpha and beta diversity being affected by environmental changes (warming and habitat size) and trophic structure (diversity of top predators). Macrofauna alpha and beta diversity was sensitive to changes in predator diversity and habitat size, but not warming. In contrast, the bacterial community was not influenced by the treatments. The community of each biological group was not mutually concordant with the environmental and trophic changes. Our results demonstrate that distinct anthropogenic impacts differentially affect the components of macro and microorganism diversity through direct and indirect effects (i.e., bottom‐up and top‐down effects). Therefore, a multitrophic and multispecies approach is necessary to assess the effects of different anthropogenic impacts on biodiversity. 相似文献
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1,3‐Regiospecific ethanolysis of soybean oil catalyzed by crosslinked porcine pancreas lipase aggregates 下载免费PDF全文
Margarita D. Ramos Letícia P. Miranda Raquel L. C. Giordano Roberto Fernandez‐Lafuente William Kopp Paulo W. Tardioli 《Biotechnology progress》2018,34(4):910-920
The preparation of crosslinked aggregates of pancreatic porcine lipase (PPL‐CLEA) was systematically studied, evaluating the influence of three precipitants and two crosslinking agents, as well as the use of soy protein as an alternative feeder protein on the catalytic properties and stability of the immobilized PPL. Standard CLEAs showed a global yield (CLEA’ observed activity/offered total activity) of less than 4%, whereas with the addition of soy protein (PPL:soy protein mass ratio of 1:3) the global yield was approximately fivefold higher. The CLEA of PPL prepared with soy protein as feeder (PPL:soy protein mass ratio of 1:3) and glutaraldehyde as crosslinking reagent (10 μmol of aldehyde groups/mg of total protein) was more active mainly because of the reduced enzyme leaching in the washing step. This CLEA, named PPL‐SOY‐CLEA, had an immobilization yield around 60% and an expressed activity around 40%. In the ethanolysis of soybean oil, the PPL‐SOY‐CLEA yielded maximum fatty acid ethyl ester (FAEE) concentration around 12‐fold higher than that achieved using soluble PPL (34 h reaction at 30°C, 300 rpm stirring, soybean oil/ethanol molar ratio of 1:5) with an enzyme load around 2‐fold lower (very likely due to free enzyme inactivation). The operational stability of the PPL‐SOY‐CLEA in the ethanolysis of soybean oil in a vortex flow type reactor showed that FAEE yield was higher than 50% during ten reaction cycles of 24 h. This reactor configuration may be an attractive alternative to the conventional stirred reactors for biotransformations in industrial plants using carrier‐free biocatalysts. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:910–920, 2018 相似文献
779.
Flávia Correa Raffaini Alice Ramos Freitas Thalisson Saymo Oliveira Silva Tarsis Cavagioni Jessica Felix Oliveira Rubens Ferreira Albuquerque Junior 《Biofouling》2018,34(2):173-182
This cross-sectional study aimed to identify and quantify up to 42 target species colonizing the early biofilm of dental implants restored with titanium or zirconia abutments. A total of 720 samples from 20 healthy individuals were investigated. Biofilm samples were collected from the peri-implant sulci, inner parts of implants, abutment surfaces and prosthetic crowns over a functioning period of 30 days. Checkerboard DNA–DNA hybridization was used for microbial detection and quantitation. Clinical characteristics (probing depth, bleeding on probing, clinical attachment level and marginal bone loss) were also investigated during the monitoring period. Genome counts were low at the implant loading time point for both the abutment materials, and increased over time. Both the titanium and the zirconia groups presented similar microbial counts and diversity over time, and the microbiota was very similar to that colonizing the remaining teeth. Clinical findings were consistent with a healthy condition with no significant difference regarding marginal bone loss between the two materials. 相似文献
780.
José Cavalcante Souza Vieira Camila Pereira Braga Grasieli de Oliveira Cilene do Carmo Federici Padilha Paula Martin de Moraes Luiz Fabricio Zara Aline de Lima Leite Marília Afonso Rabelo Buzalaf Pedro de Magalhães Padilha 《Biological trace element research》2018,181(1):164-172
Poly-trans-[(2-carboxyethyl)germasesquioxane] (Ge-132) is a water-soluble organogermanium compound that exerts various physiological effects, including anti-inflammatory activity and pain relief. In water, Ge-132 is hydrolyzed to 3-(trihydroxygermyl)propanoic acid (THGP), which in turn is capable of interacting with cis-diol compounds through its trihydroxy group, indicating that this compound could also interact with diol-containing nucleic acid constituents. In this study, we evaluated the ability of THGP to interact with nucleosides or nucleotides via nuclear magnetic resonance (NMR) analysis. In addition, we evaluated the effect of added THGP on the enzymatic activity of adenosine deaminase (ADA) when using adenosine or 2′-deoxyadenosine as a substrate. In solution, THGP indeed formed complexes with nucleotides or nucleosides through their cis-diol group. Moreover, the ability of THGP to form complexes with nucleotides was influenced by the number of phosphate groups present on the ribose moiety. Notably, THGP also inhibited the catalysis of adenosine by ADA in a concentration-dependent manner. Thus, interactions between THGP and important biological nucleic acid constituents might be implicated in the physiological effects of Ge-132. 相似文献