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41.
In the last 10 years, accelerated mineralization of Atrazine (2-chloro-ethylamino-6-isopropylamino-s-triazine) has been evidenced in agricultural soils repeatedly treated with this herbicide. Here, we report on the interaction between earthworms, considered as soil engineers, and the Atrazine-degrading community. The impact of earthworm macrofauna on Atrazine mineralization was assessed in representative soil microsites of earthworm activities (gut contents, casts, burrow linings). Soil with or without earthworms, namely the anecic species Lumbricus terrestris and the endogenic species Aporrectodea caliginosa, was either inoculated or not inoculated with Pseudomonas sp. ADP, an Atrazine-degrading strain, and was either treated or not treated with Atrazine. The structure of the bacterial community, the Atrazine-degrading activity and the abundance of atzA, B and C sequences in soil microsites were investigated. Atrazine mineralization was found to be reduced in representative soil microsites of earthworm activities. Earthworms significantly affected the structure of soil bacterial communities. They also reduced the size of the inoculated population of Pseudomonas sp. ADP, thereby contributing to the diminution of the Atrazine-degrading genetic potential in representative soil microsites of earthworm activities. This study illustrates the regulation produced by the earthworms on functional bacterial communities involved in the fate of organic pollutants in soils. 相似文献
42.
Csilla Krausz Claudia Giachini Deborah Lo Giacco Fabrice Daguin Chiara Chianese Elisabet Ars Eduard Ruiz-Castane Gianni Forti Elena Rossi 《PloS one》2012,7(10)
Context
The role of CNVs in male infertility is poorly defined, and only those linked to the Y chromosome have been the object of extensive research. Although it has been predicted that the X chromosome is also enriched in spermatogenesis genes, no clinically relevant gene mutations have been identified so far.Objectives
In order to advance our understanding of the role of X-linked genetic factors in male infertility, we applied high resolution X chromosome specific array-CGH in 199 men with different sperm count followed by the analysis of selected, patient-specific deletions in large groups of cases and normozoospermic controls.Results
We identified 73 CNVs, among which 55 are novel, providing the largest collection of X-linked CNVs in relation to spermatogenesis. We found 12 patient-specific deletions with potential clinical implication. Cancer Testis Antigen gene family members were the most frequently affected genes, and represent new genetic targets in relationship with altered spermatogenesis. One of the most relevant findings of our study is the significantly higher global burden of deletions in patients compared to controls due to an excessive rate of deletions/person (0.57 versus 0.21, respectively; p = 8.785×10−6) and to a higher mean sequence loss/person (11.79 Kb and 8.13 Kb, respectively; p = 3.435×10−4).Conclusions
By the analysis of the X chromosome at the highest resolution available to date, in a large group of subjects with known sperm count we observed a deletion burden in relation to spermatogenic impairment and the lack of highly recurrent deletions on the X chromosome. We identified a number of potentially important patient-specific CNVs and candidate spermatogenesis genes, which represent novel targets for future investigations. 相似文献43.
Anne‐Maïmiti Dulaurent Annabel J. Porté Inge van Halder Fabrice Vétillard Pierre Menassieu Hervé Jactel 《Agricultural and Forest Entomology》2012,14(1):19-27
- 1 The disruption of host‐finding cues has been proposed as a key mechanism underlying the lower damage caused by phytophagous insects in mixed forests. We tested this hypothesis by investigating the distribution of pine processionary moth Thaumetopoea pityocampa (Denis & Schiffer‐Müller) (Lepidoptera) infestation at the edges of pure stands of Pinus pinaster (AÏton) at some distance from nonhost trees (Experiment 1) or bordered in part by a broadleaved hedgerow (Experiment 2).
- 2 An ‘edge effect' was demonstrated, with trees at the edge of the stand being more heavily infested than those at the interior of the stand.
- 3 The presence of a nonhost broadleaved hedgerow in front of the edge of the pine stand resulted in lower T. pityocampa infestation. There were significantly fewer T. pityocampa nests behind the hedgerow than on the exposed part of the edge. The presence of the hedgerow did not dilute or repel T. pityocampa infestation further into the pine stand, although it decreased the infestation of T. pityocampa throughout the pine stand. The decrease in T. pityocampa infestation behind the hedgerow was greater when the broadleaved hedgerow was taller than the pine trees.
- 4 These results highlight the benefits of using nonhost tree species on the edge of monospecific forest stands to reduce insect damage. This approach could be promoted as an innovative forest pest management method.
44.
Deutsch EW Ball CA Berman JJ Bova GS Brazma A Bumgarner RE Campbell D Causton HC Christiansen JH Daian F Dauga D Davidson DR Gimenez G Goo YA Grimmond S Henrich T Herrmann BG Johnson MH Korb M Mills JC Oudes AJ Parkinson HE Pascal LE Pollet N Quackenbush J Ramialison M Ringwald M Salgado D Sansone SA Sherlock G Stoeckert CJ Swedlow J Taylor RC Walashek L Warford A Wilkinson DG Zhou Y Zon LI Liu AY True LD 《Nature biotechnology》2008,26(3):305-312
One purpose of the biomedical literature is to report results in sufficient detail that the methods of data collection and analysis can be independently replicated and verified. Here we present reporting guidelines for gene expression localization experiments: the minimum information specification for in situ hybridization and immunohistochemistry experiments (MISFISHIE). MISFISHIE is modeled after the Minimum Information About a Microarray Experiment (MIAME) specification for microarray experiments. Both guidelines define what information should be reported without dictating a format for encoding that information. MISFISHIE describes six types of information to be provided for each experiment: experimental design, biomaterials and treatments, reporters, staining, imaging data and image characterizations. This specification has benefited the consortium within which it was developed and is expected to benefit the wider research community. We welcome feedback from the scientific community to help improve our proposal. 相似文献
45.
Hélène Déméné Nathalie Jullian Nelly Morellet Hugues de Rocquigny Fabrice Cornille Bernard Maigret Bernard P. Roques 《Journal of biomolecular NMR》1994,4(2):153-170
Summary The nucleocapsid protein of Moloney murine leukemia virus (NCp10) is a 56-amino acid protein which contains one zinc finger of the CysX2CysX4HisX4Cys form, a highly conserved motif present in most retroviruses and retroelements. At pH5, NCp10 binds one zinc atom and the complexation induces a folding of the CysX2CysX4HisX4Cys box, similar to that observed for the zinc-binding domains of HIV-1 NC protein. The three-dimensional structure of NCp10 has been determined in aqueous solution by 600 MHz 1H NMR spectroscopy. The proton resonances could be almost completely assigned by means of phase-sensitive double-quantum-filtered COSY, TOCSY and NOESY techniques. NOESY spectra yielded 597 relevant structural constraints, which were used as input for distance geometry calculations with DIANA. Further refinement was performed by minimization with the program AMBER, which was modified by introducing a zinc force field. The solution structure is characterized by a well-defined central zinc finger (rmsd of 0.747±0.209 Å for backbone atoms and 1.709±0.187 Å when all atoms are considered), surrounded by flexible N- and C-terminal domains. The Tyr28, Trp35, Lys37, Lys41 and Lys42 residues, which are essential for activity, lie on the same face of the zinc finger, forming a bulge structure probably involved in viral RNA binding. The significance of these structural characteristics for the various biological functions of the protein is discussed, taking into account the results obtained with various mutants. 相似文献
46.
Fabrice Neiers Chaithanya Madhurantakam Stefan Fälker Clothilde Manzano Staffan Normark Adnane Achour 《Journal of molecular biology》2009,393(3):704-352
The respiratory tract pathogen Streptococcus pneumoniae is a primary cause of morbidity and mortality worldwide. Pili enhance initial adhesion as well as the capacity of pneumococci to cause pneumonia and bacteremia. Pilus-associated sortases (SrtB, SrtC, and SrtD) are involved in the biogenesis of pneumococcal pili, composed of repeating units of RrgB that create the stalk to which the RrgA adhesin and the preferential pilus tip subunit RrgC are covalently associated. Using single sortase-expressing strains, we demonstrate that both pilin-polymerizing sortases SrtB and SrtC can covalently link pili to the peptidoglycan cell wall, a property shared with the non-pilus-polymerizing enzyme SrtD and the housekeeping sortase SrtA. Comparative analysis of the crystal structures of S. pneumoniae SrtC and SrtB revealed structural differences explaining the incapacity of SrtC, but not of SrtB, to incorporate RrgC into the pilus. Accordingly, site-directed mutagenesis of Thr160 in SrtB to an arginine as in SrtC (Arg160) partially converted its substrate specificity into that of SrtC. Solving two crystal structures for SrtC suggests that an opening of a flexible lid and a concomitant cysteine rotation are important for catalysis and the activation of the catalytic cysteine of pilus-associated sortases. 相似文献
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49.
Thomas Noe Perry Hager Souabni Chiara Rapisarda Rémi Fronzes Fabrice Giusti Jean-Luc Popot Manuela Zoonens Francesca Gubellini 《生物化学与生物物理学报:生物膜》2019,1861(2):466-477
Membrane protein (MP) complexes play key roles in all living cells. Their structural characterisation is hampered by difficulties in purifying and crystallising them. Recent progress in electron microscopy (EM) have revolutionised the field, not only by providing higher-resolution structures for previously characterised MPs but also by yielding first glimpses into the structure of larger and more challenging complexes, such as bacterial secretion systems. However, the resolution of pioneering EM structures may be difficult and their interpretation requires clues regarding the overall organisation of the complexes. In this context, we present BAmSA, a new method for localising transmembrane (TM) regions in MP complexes, using a general procedure that allows tagging them without resorting to neither genetic nor chemical modification. Labels bound to TM regions can be visualised directly on raw negative-stain EM images, on class averages, or on three-dimensional reconstructions, providing a novel strategy to explore the organisation of MP complexes. 相似文献
50.
Dellagi K Rollot O Temmam S Salez N Guernier V Pascalis H Gérardin P Fianu A Lapidus N Naty N Tortosa P Boussaïd K Jaffar-Banjee MC Filleul L Flahault A Carrat F Favier F de Lamballerie X 《PloS one》2011,6(9):e25738