Improving the germination of economically important crops and the condition of young plants is a major challenge currently facing agricultural practice. Pea (Pisum sativum L.) is one of the four most important cultivated legumes, along with groundnut (Arachis hypogaea L.), soybean (Glycine max L.) and beans (Phaseolus vulgaris L.). Due to the high protein content (23–33%), there is an interest in growing this crop as a source of protein for humans and animals. In this study, we focused on the effect of Cold Atmospheric Pressure Plasma (CAPP) on the decontamination and germination of pea seeds, on young seedling growth and production parameters, and on increasing their resistance and mechanical strength. We can state that germination increased by 10 to 25% after plasma treatment, and the most significant decontamination effect was detected when using non-thermal plasma generated in the ambient air (A-variants) and in the nitrogen atmosphere (N-variants). The increased in situ activity of peroxidases (POX) in the cell walls of A-variants and N-variants is also closely related to the increase in the mechanical strength of the cell walls and thus contributes to the higher resistance of these seedlings. This is also illustrated by the differences in lignin deposition among the different variants after CAPP treatment. To our knowledge, this is the first study concerning the influence of CAPP on the lignification of root tissues and on increasing the strength and resistance of plants.
Nucleation and growth of amyloid fibrils were found to only occur in supersaturated solutions above a critical concentration (ccrit). The biophysical meaning of ccrit remained mostly obscure, since typical low values of ccrit in the sub-μM range hamper investigations of potential oligomeric states and their structure. Here, we investigate the parathyroid hormone PTH84 as an example of a functional amyloid fibril forming peptide with a comparably high ccrit of 67±21 μM. We describe a complex concentration dependent prenucleation ensemble of oligomers of different sizes and secondary structure compositions and highlight the occurrence of a trimer and tetramer at ccrit as possible precursors for primary fibril nucleation. Furthermore, the soluble state found in equilibrium with fibrils adopts to the prenucleation state present at ccrit. Our study sheds light onto early events of amyloid formation directly related to the critical concentration and underlines oligomer formation as a key feature of fibril nucleation. Our results contribute to a deeper understanding of the determinants of supersaturated peptide solutions. In the current study we present a biophysical approach to investigate ccrit of amyloid fibril formation of PTH84 in terms of secondary structure, cluster size and residue resolved intermolecular interactions during oligomer formation. Throughout the investigated range of concentrations (1 μM to 500 μM) we found different states of oligomerization with varying ability to contribute to primary fibril nucleation and with a concentration dependent equilibrium. In this context, we identified the previously described ccrit of PTH84 to mark a minimum concentration for the formation of homo-trimers/tetramers. These investigations allowed us to characterize molecular interactions of various oligomeric states that are further converted into elongation competent fibril nuclei during the lag phase of a functional amyloid forming peptide. 相似文献
The structures of the O‐glycosyltransferase LanGT2 and the engineered, C? C bond‐forming variant LanGT2S8Ac show how the replacement of a single loop can change the functionality of the enzyme. Crystal structures of the enzymes in complex with a nonhydrolyzable nucleotide‐sugar analogue revealed that there is a conformational transition to create the binding sites for the aglycon substrate. This induced‐fit transition was explored by molecular docking experiments with various aglycon substrates. 相似文献
A case study of the robust model-based predictive control (MPC) of an exothermic continuous stirred tank reactor (CSTR) with uncertain parameters is presented. Three robust MPC approaches are considered and the simulation results are compared in terms of quality of control performance and total consumption of coolant. The results reveal the main benefits of the considered approaches and confirm that the robust MPC can bring about a reduction in consumption of the coolant. 相似文献
In our study, we examined 91 fecal samples from five different groups of people containing HIV patients, hemodialysis patients, kidney transplant recipients, immunocompetent humans without clinical signs, and humans with suspected cryptosporidiosis. The purpose of our study was to determine species and genotype composition of representatives of Cryptosporidium spp. using PCR analysis of small subunit ribosomal RNA gene and 60‐kDa glycoprotein gene and examine their phylogenetic relationship. In HIV‐positive/AIDS‐infected group of patients and in hemodialysis patients, no presence of Cryptosporidium species was detected. In two kidney transplant recipients, we detected species/genotypes Cryptosporidium parvum IIaA13G1T1R1 (KT355488) and Cryptosporidium hominis IaA11G2R8 (KT355489) and in two immunocompetent patients with clinical symptoms, we identified Cryptosporidium muris and C. hominis IbA10G2T1 (KT355490). In the group of healthy immunocompetent individuals without clinical signs, we identified species/genotype C. hominis IbA11G2 (KT355491) in one sample. 相似文献
Hirshfeld surfaces and two‐dimensional fingerprint plots are used to analyse the intermolecular interactions in two new phosphorothioic triamide structures, namely N,N′,N′′‐tris(3,4‐dimethylphenyl)phosphorothioic triamide acetonitrile hemisolvate, P(S)[NHC6H3‐3,4‐(CH3)2]3·0.5CH3CN or C24H30N3PS·0.5CH3CN, (I), and N,N′,N′′‐tris(4‐methylphenyl)phosphorothioic triamide–3‐methylpiperidinium chloride (1/1), P(S)[NHC6H4(4‐CH3)]3·[3‐CH3‐C5H9NH2]+·Cl− or C21H24N3PS·C6H14N+·Cl−, (II). The asymmetric unit of (I) consists of two independent phosphorothioic triamide molecules and one acetonitrile solvent molecule, whereas for (II), the asymmetric unit is composed of three components (molecule, cation and anion). In the structure of (I), the different components are organized into a six‐molecule aggregate through N—H...S and N—H...N hydrogen bonds. The components of (II) are aggregated into a two‐dimensional array through N—H...S and N—H...Cl hydrogen bonds. Moreover, interesting features of packing arise in this structure due to the presence of a double hydrogen‐bond acceptor (the S atom of the phosphorothioic triamide molecule) and of a double hydrogen‐bond donor (the N—H unit of the cation). For both (I) and (II), the full fingerprint plot of each component is asymmetric as a consequence of the presence of three fragments. These analyses reveal that H...H interactions [67.7 and 64.3% for the two symmetry‐independent phosphorothioic triamide molecules of (I), 30.7% for the acetonitrile solvent of (I), 63.8% in the phosphorothioic triamide molecule of (II) and 62.9% in the 3‐methylpiperidinium cation of (II)] outnumber the other contacts for all the components in both structures, except for the chloride anion of (II), which only receives the Cl...H contact. The phosphorothioic triamide molecules of both structures include unsaturated C atoms, thus presenting C...H/H...C interactions: 17.6 and 21% for the two symmetry‐independent phosphorothioic triamide molecules in (I), and 22.7% for the phosphorothioic triamide molecule of (II). Furthermore, the N—H...S hydrogen bonds in both (I) and (II), and the N—H...Cl hydrogen bonds in (II), are the most prominent interactions, appearing as large red spots on the Hirshfeld surface maps. The N...H/H...N contacts in structure (I) are considerable, whereas for (II), they give a negligible contribution to the total interactions in the system. 相似文献