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891.
Parkinson's disease (PD) is a neurodegenerative disorder involving progressive deterioration of dopaminergic neurons. Although few genetic markers for familial PD are known, the etiology of sporadic PD remains poorly understood. Microarray data was analysed for induced pluripotent stem cells (iPSCs) derived from PD patients and mature neuronal cells (mDA) differentiated from these iPSCs. Combining expression and semantic similarity, a highly-correlated PD interactome was constructed that included interactions of established Parkinson's disease marker genes. A novel three-way comparative approach was employed, delineating topologically and functionally important genes. These genes showed involvement in pathways like Parkin-ubiquitin proteosomal system (UPS), immune associated biological processes and apoptosis. Of interest are three genes, eEF1A1, CASK, and PSMD6 that are linked to PARK2 activity in the cell and thereby form attractive candidate genes for understanding PD. Network biology approach delineated in this study can be applied to other neurodegenerative disorders for identification of important genetic regulators.  相似文献   
892.
Nematodes are responsible for causing severe diseases in plants, humans and other animals. Infection is associated with the release of Excretory/Secretory (ES) proteins into host cytoplasm and interference with the host immune system which make them attractive targets for therapeutic use. The identification of ES proteins through bioinformatics approaches is cost- and time-effective and could be used for screening of potential targets for parasitic diseases for further experimental studies. Here, we identified and functionally annotated 93,949 ES proteins, in the genome of 73 nematodes using integration of various bioinformatics tools. 30.6% of ES proteins were found to be supported at RNA level. The predicted ES proteins, annotated by Gene Ontology terms, domains, metabolic pathways, proteases and enzyme class analysis were enriched in molecular functions of proteases, protease inhibitors, c-type lectin and hydrolases which are strongly associated with typical functions of ES proteins. We identified a total of 452 ES proteins from human and plant parasitic nematodes, homologues to DrugBank-approved targets and C. elegans RNA interference phenotype genes which could represent potential targets for parasite control and provide valuable resource for further experimental studies to understand host-pathogen interactions.  相似文献   
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894.
The stochasticity of Aspergillus oryzae (Trivially: the koji mold) pan-metabolomes commensurate with its ubiquitously distributed landscapes, i.e. growth matrices have been seemed uncharted since its food fermentative systems are mostly being investigated. In this review, we explicitly have discussed the likely tendencies of A. oryzae metabolomes pertaining to its growth milieu formulated with substrate matrices of varying nature, composition, texture, and associated physicochemical parameters. We envisaged typical food matrices, namely, meju, koji, and moromi as the semi-natural cultivation models toward delineating the metabolomic patterns of the koji mold, which synergistically influences the organoleptic and functional properties of the end products. Further, we highlighted how tailored conditions in sub-natural growth matrices, i.e. synthetic cultivation media blends, inducers, and growth surfaces, may influence A. oryzae metabolomes and targeted phenotypes. In general, the sequential or synchronous growth of A. oryzae on formulated matrices results in a number of metabolic tradeoffs with its immediate microenvironment influencing its adaptive and regulatory metabolomes. In broader context, evaluating the metabolic plasticity of A. oryzae relative to the tractable variables in formulated growth matrices might help approximate its growth and metabolism in the more complex natural matrices and environs. These approaches may considerably help in the design and manipulation of hybrid cultivation systems towards the efficient harnessing of commercial molds.  相似文献   
895.
Plant Molecular Biology Reporter - The original version of this article unfortunately contained missing information at author’s affiliations. The affiliation address of the author’s...  相似文献   
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897.
To study the effect of conserved cysteins on biochemical properties of a previously cloned metagenomic polygalacturonase (PecJKR01), single point variants A42C, M283C, and double variants M283C + F24C, M283C + A42C were constructed. Mutations resulted in shifting the pH toward lower range and enhanced thermostability. The mutants were optimally active at pH 5.0 as compared to pH 7.0 for wild type. Point variants demonstrated slightly higher enzyme activity at 60o C than that of the wild type. In addition, the A42C/M283C + A42C variants displayed nearly 28–40% enhanced thermostability, while M283C + 24C was least thermostable among all variants/ wild type. Cys (pKa 8.18) possibly interfered in the ionization state resulting in change in pH optima of variants. Structure function analysis suggested that the increased activity in A42C could be due to van der Waals interactions in S···Ar with Phe29 and formation of an additional hydrogen bond between Cys42-S....HN-Ala31. Higher thermostability and decreased enzymatic activity of M283C might be attributed to the incorporation of additional disulfide linkage between Cys283 S=S Cys255 and decreased cavity size. Overall cysteine at position 42 was most promising in shifting the optimum pH toward lower range as well as for thermostability of enzyme.  相似文献   
898.
Outbreak of Human Herpes virus-5 (HHV-5) infection in emerging countries has raised worldwide health concern owing to prevalence of congenital impairments and life threatening consequences in immunocompromised individuals. Thus, there lies an impending need to develop vaccine against HHV-5. HHV-5 enters into host cells with the help of necessary components glycoprotein B (gB) and H/L. In this study, the conformational linear B-cell and T-cell epitopes for gB of HHV-5 have been predicted using conformational approaches, for their possible collective use as vaccine candidates. We examined epitope’s interactions with major histocompatibility complexes using molecular docking and also investigated their stable binding with specific toll like receptor-2 (TLR2), present on host cells during HHV-5 infection. Predicted MHC-I epitope ‘LVAIAVVII’ with high antigenicity and large coverage of HLA alleles was found to superimpose on MHC-II epitope (Rank 1) and was also identified to be the core sequence of putative B cell epitope ‘ILVAIAVVIITYLI’. Resulting epitope was found to have consistent interaction with TLR2 during long term (100?ns) MD run. We also validated this nonamer epitope for its dissimilarity with human genome and high population coverage, suggesting it to be a potential vaccine candidate with higher coverage for both the MHC alleles of Indian population.

Communicated by Ramaswamy H. Sarma  相似文献   

899.

Iron deficiency anaemia is a major challenge among consumers in developing countries. Given the deficiency of iron in the diet, there is an urgent need to devise a strategy for providing the required iron in the daily diet to counter the iron deficiency anaemia. We propose that iron biofortification of wheat (Triticum aestivum L.) through seed priming would be an innovative strategy to address this issue. This investigation attempts to find the interaction of iron oxide nanoparticles on germination, growth parameters and accumulation of grain iron in two contrasting wheat genotypes WL711 (low-iron genotype) and IITR26 (high-iron genotype). Wheat seeds were primed with different concentrations of iron oxide nanoparticles in the range of 25–600 ppm, resulting in differential accumulation of grain iron contents. We observed a pronounced increase in germination percentage and shoot length at 400 and 200 ppm treatment concentrations in IITR26 and WL711 genotypes, respectively. Intriguingly, the treatment concentration of 25 ppm demonstrated higher accumulation with a significant increase in grain iron contents to 45.7% in IITR26 and 26.8% in WL711 genotypes, respectively. Seed priming represents an innovative and user-friendly approach for wheat biofortification which triggers iron acquisition and accumulation in grains.

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900.
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