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21.
We have cloned and sequenced a cDNA of the human homologue of the Saccharomyces cerevisiae Suv3 putative RNA helicase which is indispensable for mitochondrial function in yeast. The human Suv-3-like protein has a typical mitochondrial leader sequence. Northern blot data and analysis of ESTs in the data banks indicate that this human gene (SUPV3L1) is expressed in practically all tissues, though at different levels. Sequence homology analysis has shown a strong conservation of the protein in a number of eukaryotic organisms -- plants, mammals and fungi, but no close homologues exist in bacteria with the exception of the purple bacterium Rhodobacter sphaeroides. This gene is thus ubiquitously present in all eukaryotic organisms.  相似文献   
22.
The state of the macrophyte community of Zostera marina + Stephanocystis crassipes in the cove off Cape Tokarevsky (Eastern Bosphorus Strait, Sea of Japan) was evaluated, using the method of sample plots, in June 2014. The taxonomical and morpho-functional composition, as well as the structure of the community, has been studied. A total of 39 species of marine macrophytes have been found in this area, including 6 species of Chlorophyta, 22 species of Rhodophyta, 10 species of Phaeophyceae, and 1 species of Tracheophyta (Zostera marina), which constitute 15, 56, 26, and 3% of the total number of species in the community, respectively. The studied phytocenosis is characterized by a poor taxonomic composition, a high biomass of opportunistic species (auxiliary species on the dominance scale), and the proportions of higher algal taxa typical of the clean waters of Peter the Great Bay. Thus, based on a combination of these characteristics, the Zostera marina + Stephanocystis crassipes phytocenosis can be regarded as being in an early stage of anthropogenic transformation and the waters are classified as moderately polluted.  相似文献   
23.
Aggregation of Amyloid β (Aβ) in the interneuronal spaces is a major etiopathological factor for onset and progression of Alzheimer’s disease (AD). Since the mechanism of aggregation is not fully understood, control and modulation of the aggregation process is a challenging task. Although, several strategies were developed for the past few decades, yet there is no proper therapeutics available. Herein, we report a peptide based pro-drug, termed as a conformational Pro-Drug peptide (PDp), which disrupts existing Aβ fibrils, but does not produce toxic soluble oligomers, through a series of spontaneous chemical reactions resulting in in situ generation of β-sheet destabilizing factors. Furthermore, PDp reduces Aβ mediated toxicity examined on an in vitro model consisting of the human neuroblastoma SH-SY5Y cells. PDp also disrupts fibrils originated from AD affected human cerebrospinal fluid. These findings will help to understand the process of amyloidogenesis better and also indicate a novel approach for therapeutically important peptide design.  相似文献   
24.
25.
The second-most common cause of death resulting from genetic mutations in DNA sequences is cancer. The difficulty in the field of anticancer research is the application of the traditional methods, which also affects normal cells. Mutations, genetic replication alterations, and chromosomal abnormalities have a direct impact on the effectiveness of anticancer drugs at different stages. Presently, therapeutic techniques utilize nanotechnology, transition metal dichalcogenides (TMDCs), and robotics. TMDCs are being increasingly employed in tumor therapy and biosensing applications due to their biocompatibility, adjustable bandgap, versatile functionality, exceptional photoelectric properties, and wide range of applications. This study reports the advancement of nanoplatforms based on TMDCs that are specifically engineered for responsive and intelligent cancer therapy. This article offers a thorough examination of the current challenges, future possibilities for theranostic applications using TMDCs, and recent progress in employing TMDCs for cancer therapy. Currently, there is significant interest in two-dimensional (2D) TMDCs nanomaterials as ultrathin unique physicochemical properties. These materials have attracted attention in various fields, including biomedicine. Due to their inherent ability to absorb near-infrared light and their exceptionally large surface area, significant efforts are being made to prepare multifunctional nanoplatforms based on 2D TMDCs.  相似文献   
26.
The combined effect of temperature (5, 10, 15, and 20°C) and illumination (40 and 60 mE/(m2 s)) on growth and reproduction of the green marine alga Ulva fenestrata P. et R. from the sublittoral zone of Amursky Bay, Sea of Japan, was studied in the laboratory environment in the months April–July, 2000. It was demonstrated that the temperature of 5°C and illumination of 40 mE/(m2 s) are the most favorable for maintaining the vegetative mass of the algae. A water temperature of 10°C and illumination of 40 mE/(m2 s) are the optimum conditions for vegetative growth of U. fenestrata thalli. A temperature decrease and increase by 5°C reduces the growth rate on average by 30%. Sporo- and gametogenesis in U. fenestrata are the most regular (every 10 days) and occupy the greatest disk area at a water temperature of 15°C and illumination of 40 mE/(m2 s). Vegetative growth of thalli is sharply inhibited at the stage of cell preparation to gametogenesis a day before the beginning of gamete formation.  相似文献   
27.
Horsegram [Macrotyloma uniflorum (Lam.) Verdc.) is an important grain legume and fodder crop in India. Information on root nodule endosymbionts of this legume in India is limited. In the present study, 69 isolates from naturally occurring root nodules of horsegram collected from two agro-eco-climatic regions of South India was analyzed by generation rate, acid/alkali reaction on YMA medium, restriction fragment length polymorphism analysis of 16S-23S rDNA intergenic spacer region (IGS), and sequence analyses of IGS and housekeeping genes glnII and recA. Based on the rDNA IGS RFLP by means of three restriction enzymes rhizobia were grouped in five clusters (I–V). By sequence analysis of 16S-23S rDNA IGS identified genotypes of horsegram rhizobia were distributed into five divergent lineages of Bradyrhizobium genus which comprised (I) the IGS type IV rhizobia and valid species B. yuanmingense, (II) the strains of IGS type I and Bradyrhizobium sp. ORS 3257 isolated from Vigna sp., (III) the strains of the IGS type II and Bradyrhizobium sp. CIRADAc12 from Acacia sp., (IV) the IGS type V strains and Bradyrhizobium sp. genospecies IV, and (V) comprising genetically distinct IGS type III strains which probably represent an uncharacterized new genomic species. Nearly, 87% of indigenous horsegram isolates (IGS types I, II, III, and V) could not be related to any other species within the genus Bradyrhizobium. Phylogeny based on housekeeping glnII and recA genes confirmed those results found by the analysis of the IGS sequence. All the isolated rhizobia nodulated Macrotyloma sp. and Vigna spp., and only some of them formed nodules on Arachis hypogeae. The isolates within each IGS type varied in their ability to fix nitrogen. Selection for high symbiotic effective strains could reward horsegram production in poor soils of South India where this legume is largely cultivated.  相似文献   
28.
Assam hill goat (Capra hircus) is a prolific local goat in India. bone morphogenetic protein receptor (BMPR1B) gene was studied as a candidate gene for the prolificacy of goats. The objective of the present study was to detect the incidence of mutation in the exonic region of BMPR1B gene of Assam hill goat. Total 90 blood samples were collected randomly from different parts of Assam and genomic DNA were extracted using phenol–chloroform method. The quantity and quality of extracted DNA was examined by spectrophotometry and gel electrophoresis, respectively. PCR amplicon showed a product of 140 bp fragment of BMPR1B gene. The purified product upon digestion with AvaII showed monomorphic banding pattern and revealed wild type alleles with AA genotype. Nucleotide sequencing showed one new mutation 773 (G→C) which is found to be unique in Assam hill goat. Construction of tree at nucleotide level generates from the present experiment lies in common cluster which differs from the other breeds of goat. The analysis of polymorphism for BMPR1B in Assam hill goat indicates that the genetic factor responsible for prolificacy or multiple kidding rates is not related to the reported mutated alleles of BMPR1B gene. Therefore, attempts to be made to detect other SNPs for BMPR1B gene or otherwise effort should be made towards other fecundity gene which might be responsible for the prolificacy of Assam hill goat.  相似文献   
29.
Protein complexes are known to play a major role in controlling cellular activity in a living being. Identifying complexes from raw protein protein interactions (PPIs) is an important area of research. Earlier work has been limited mostly to yeast. Such protein complex identification methods, when applied to large human PPIs often give poor performance. We introduce a novel method called CSC to detect protein complexes. The method is evaluated in terms of positive predictive value, sensitivity and accuracy using the datasets of the model organism, yeast and humans. CSC outperforms several other competing algorithms for both organisms. Further, we present a framework to establish the usefulness of CSC in analyzing the influence of a given disease gene in a complex topologically as well as biologically considering eight major association factors.  相似文献   
30.
Fasciola gigantica is the causative organism of fascioliasis and is responsible for major economic losses in livestock production globally. F. gigantica thioredoxin1 (FgTrx1) is an important redox-active enzyme involved in maintaining the redox homeostasis in the cell. To identify a potential anti-fasciolid compound, we conducted a structure-based virtual screening of natural compounds from the ZINC database (n = 1,67,740) against the FgTrx1 structure. The ligands were docked against FgTrx1 and 309 ligands were found to have better docking score. These compounds were evaluated for Lipinski and ADMET prediction, and 30 compounds were found to fit well for re-docking studies. After refinement by molecular docking and drug-likeness analysis, three potential inhibitors (ZINC15970091, ZINC9312362, and ZINC9312661) were identified. These three ligands were further subjected to molecular dynamics simulation (MDS) to compare the dynamics and stability of the protein structure after binding of the ligands. The binding free energy analyses were calculated to determine the intermolecular interactions. The results suggested that the two compounds had a binding free energy of –82.237, and –109.52 kJ.mol?1 for compounds with IDs ZINC9312362 and ZINC9312661, respectively. These predicted compounds displayed considerable pharmacological and structural properties to be drug candidates. We concluded that these two compounds could be potential drug candidates to fight against F. gigantica parasites.  相似文献   
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