A detailed bioinformatics analysis of six glycopeptide biosynthetic gene clusters isolated from soil environmental DNA (eDNA) megalibraries indicates that a subset of these gene clusters contains ...collections of tailoring enzymes that are predicted to result in the production of new glycopeptide congeners. In particular, sulfotransferases appear in eDNA-derived gene clusters at a much higher frequency than would be predicted from the characterization of glycopeptides from cultured Actinomycetes. Enzymes found on tailoring-enzyme-rich eDNA clones associated with these six gene clusters were used to produce a series of new sulfated glycopeptide derivatives in both in vitro and in vivo derivatization studies. The derivatization of known natural products with eDNA-derived tailoring enzymes is likely to be a broadly applicable strategy for generating libraries of new natural product variants.
In this work we perform a theoretical study of dehydrogenation process of CH4 on O2– in both molecular and dissociative states - previously adsorbed on Cr2O3(0001). Calculations are based on Density ...Functional Theory (DFT). The results show the methanol formation form the adsorption of CH4 on O2 in dissociative state with a formationenergy5:14 eV. Also formaldehyde was formed by the reaction of CH2with molecular O2(Eads=6:09 eV) and dioxymethylene by the reaction of CH2with O2 previously adsorbed in dissociative state on Cr2O3(0001), withEads=8:17 eV. Finally, the vibrational modes found by DFT for each of the species were compared, which are in good agreement with those of reference bibliography. This allows us to support the values found both by technical calculations and by experimental methods.
Objetivos: Determinar la mortalidad de larvas de distintos estadios de Spodoptera frugiperda y la eficacia del control, con el uso del nematodo entomopatógeno Heterorhabditis bacteriophora Poinar. ...Metodología: Bajo -1 condiciones de laboratorio, se inocularon concentraciones de 10, 100 y 200 nematodos mL sobre los estadios larvales II, III, IV y V de S. frugiperda con aspersiones dirigidas. Se evaluó el porcentaje de mortalidad a los 24, 48, 72 y 96 horas después de la inoculación; así mismo, se determinó el porcentaje de eficacia de control. Resultados: Las larvas de S. frugiperda inoculadas con H. bacteriophora presentaron mortalidad en sus distintos estadios larvales; los estadios con mayor porcentaje de muerte fueron IV y V. Las concentraciones más efectivas -1 que causaron mayor porcentaje de mortalidad fueron 100 y 200 individuos mL . H. bacteriophora causó la mortalidad en gran porcentaje de larvas de S. frugiperda, logrando provocar la muerte de hasta el 75% de la población evaluada del V estadio. Conclusiones: Existe una relación directa entre la concentración del nematodoy el porcentaje de mortalidad en larvas de S. frugiperda; la concentración de 200 nematodos mL -1 logró el más alto control de S. frugiperda. Los estadios larvales IV y V son los más sensibles a la aplicación del nematodo.Palabras clave: Entomopatógeno, nematodo, Heterorhabditis, Spodoptera frugiperda, maíz
In this paper, nanoparticle dispersions (nanosilver, copper nano oxide, nanozinc, and nanosilica) have been formulated to be used as protective impregnants. Since all the components of the ...formulations could be charged according to the pH of the medium, the solutions were formulated with the two profiles of pH=3 and pH=8 (pH changes were handled with the addition of HCl or NH4OH at the time of application), and the interaction capacity has been analyzed. The nanoparticle dispersion medium was alcohol, and the concentrations ranged from 1 to 3% m/v. Impregnations have been performed by immersion. All formulated systems generated good protection against biotic agents due to chemical and structural modifications of the cell wall. It has been observed that the best performances were given with the presence of nanoparticles, which allowed inferring that the composite formed by nano-wood is bioactive. An issue that is also important is that the systems are easy to apply and very low concentrations are required, which translates into low costs.
The leukocyte podosome Calle, Yolanda; Burns, Siobhan; Thrasher, Adrian J. ...
European journal of cell biology,
04/2006, Letnik:
85, Številka:
3
Journal Article
Recenzirano
Myeloid leukocytes are the first line of host defence. When they sense perturbations in tissue homeostasis such as infection, inflammation and ischemia, they respond by trafficking. Whilst ...neutrophils and macrophages migrate to sites of infection, dendritic cells (DC) migrate from tissue-resident sites back into lymph nodes where they activate T and B lymphocytes. The directed migration of these leukocytes through peripheral tissues is thus crucial for their function. This article considers recent advances in our understanding of the adhesive and motile behaviour of macrophages and DC, with particular emphasis on the podosomes that appear to be required for normal migration through extracellular matrices.
Biomaterials used as cell growth stimulants should be able to provide adequate cell adhesion with no alteration in cell function. In this work, we developed a 3D model of mouse spinal cord ...motoneurons on scaffolds composed of electrospun PLA fibers and plasma-polymerized PPy-coated PLA fibers.
The functionality of the cultured motoneurons was assessed by evaluating both the electrophysiological response (i.e., the whole-cell Na+ and K+ currents and the firing of action potentials) and also the expression of the VAChaT by immunostaining techniques. While the expression of the VAChaT was confirmed on motoneurons cultured on the fibrous scaffolds, the electrophysiological responses indicated Na+ and K+ currents with lower amplitude and slower action potentials when compared to the response recorded from spinal cord motoneurons cultured on Poly-DL-Ornithine/Laminin- and plasma-polymerized PPy-coated coverslips.
From a morphological viewpoint, motoneurons cultured on PLA and PPy-coated PLA scaffolds did not show the development of dendritic and/or axonal processes, which were satisfactorily observed in the bidimensional cultures.
We hypothesize that the apparently limited development of dendritic and/or axonal processes could produce a deleterious effect on the electrophysiological response of the cells, which might be due to the limited growth surface available in the fibrous scaffolds and/or to an undesired effect of the purification process.
This paper aims to analyse the level of commitment with the SDGs of large Spanish companies based on the information published in their Non-Financial Statements and their letters from the chairman. ...To achieve this objective and identify potential explanatory factors, a balanced sample of 58 Spanish companies, 29 listed and 29 unlisted, in 2019 has been used. The results of this study evidence: i) the greater commitment with the SDGs of companies which are exposed in the stock markets and those which are larger; ii) the relevance of the diversity into the boards of directors, in order to integrate the largest and the widest number of interests as well as those values and principles which are intrinsically associated to women directors; and iii) the greater emphasis on those SDGs related to well-known issues by these organizations, thanks to their greater experience in non-financial reporting, publishing documents such as corporate social responsibility or sustainability reports.
The Wiskott-Aldrich syndrome protein (WASp) is a key cytoskeletal regulator in hematopoietic cells. Covalent modification of a conserved tyrosine by phosphorylation has emerged as an important ...potential determinant of activity, although the physiological significance remains uncertain. In a murine knockin model, mutation resulting in inability to phosphorylate Y293 (Y293F) mimicked many features of complete WASp-deficiency. Although a phosphomimicking mutant Y293E conferred enhanced actin-polymerization, the cellular phenotype was similar due to functional dysregulation. Furthermore, steady-state levels of Y293E-WASp were markedly reduced compared to wild-type WASp and Y293F-WASp, although partially recoverable by treatment of cells with proteasome inhibitors. Consequently, tyrosine phosphorylation plays a critical role in normal activation of WASp in vivo, and is indispensible for multiple tasks including proliferation, phagocytosis, chemotaxis, and assembly of adhesion structures. Furthermore, it may target WASp for proteasome-mediated degradation, thereby providing a default mechanism for self-limiting stimulation of the Arp2/3 complex.
PDF
