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Ten predominant bacteria (CSB 1-10), isolated from chromite mine soil of Sukinda, Odisha, were characterized by means of biochemical and 16S rRNA gene sequencing. All of the bacterial isolates were Gram-positive, spore-forming, and motile rods with diameter ranging from 1.57–2.79 μm and identified as Bacillus species. Based on 16S rRNA gene sequencing and phylogenetic tree construction, 10 Bacillus species were grouped into two clusters: Bacillus subtilis cluster with four species (two of B. amyloliquefaciens, and one each of B. tequilensis and B. mojavensis); and Bacillus cereus cluster containing six species of B. cereus. Secondary rRNA structure predicted for all 10 bacteria using 16S rRNA sequences revealed some degree of genetic variations among the species. Among the isolated bacteria, CSB-9 was found to be the most efficient chromate reducing strain (0.8 × 10?4 mg mg?1 h?1) in comparison to the others. Chromate reduction of the bacteria was associated with the contribution of extracellular enzyme production, and highest enzyme activity (0.9 ± 0.09 U mL?1) was observed in CSB-9 (B. amyloliquefaciens). The present study revealed the dominance of Bacillus species in the chromite mine soil and their potential for bioremediation of hexavalent chromium from the polluted environments.  相似文献   
74.
A natural red dye which is produced by the tiny insects Kerria lacca while feeding on host trees is popularly known as lac dye. Lac dye is a mixture of at least five closely related pure compounds all being anthraquinone derivatives designated as laccaic acid A, B, C, D and E. Anthraquinones isolated from different natural sources and reported to have potent antimicrobial activity. The lac dye, which is also a mixture of anthraquinone derivatives, is expected to exhibit antifungal and antibacterial activity. Lac dye cannot be used as antibacterial and antifungal agent due to its low water solubility and high polarity. Therefore, it is modified into its methyl derivative to enhance its bio-efficacy. Methylated lac dye is characterized with the help of TLC, UV–Vis spectroscopy and FT-IR, NMR analysis. An in vitro spore germination assay was carried out to evaluate the antifungal efficacy of methylated lac dye against some phytopathogenic fungi which commonly caused a various foliar diseases in crop plants viz., Alternaria solani, Curvularia lunata, Erysiphe pisi, Helminthosporium oryzae and Verticillium sp. Among the tested fungi, Verticillum sp. showed highest sensitivity, which showed 100% inhibition at 750 and 1000 µg/ml as compared to control. However, E. pisi an obligate parasite also showed varied sensitivity but at 1000 µg/ml showed 100% spore germination as compared to control. Methylated lac dye also showed strong antibacterial properties against Ralstonia solanacearum at very low concentration (40 and 50 µg/ml). Hence, lac dye may serve as potent antifungal and antibacterial agent in plant disease management.  相似文献   
75.
AimThe objective of this research was to estimate the dose distribution delivered by radioactive gold nanoparticles (198AuNPs or 199AuNPs) to the tumor inside the human prostate as well as to normal tissues surrounding the tumor using the Monte-Carlo N-Particle code (MCNP-6.1.1 code).BackgroundRadioactive gold nanoparticles are emerging as promising agents for cancer therapy and are being investigated to treat prostate cancer in animals. In order to use them as a new therapeutic modality to treat human prostate cancer, accurate radiation dosimetry simulations are required to estimate the energy deposition in the tumor and surrounding tissue and to establish the course of therapy for the patient.Materials and methodsA simple geometrical model of a human prostate was used, and the dose deposited by 198AuNPs or 199AuNPs to the tumor within the prostate as well as to the healthy tissue surrounding the prostate was calculated using the MCNP code. Water and A-150 TEP phantoms were used to simulate the soft and tumor tissues.ResultsThe results showed that the dose due to 198AuNPs or 199AuNPs, which are distributed homogenously in the tumor, had a maximal value in the tumor region and then rapidly decreased toward the prostate–tumor interface and surrounding organs. However, the dose deposited by 198Au is significantly higher than the dose deposited by 199Au in the tumor region as well as normal tissues.ConclusionsAccording to the MCNP results, 198AuNPs are a promising modality to treat prostate cancer and other cancers and 199AuNPs could be used for imaging purposes.  相似文献   
76.
Understanding rooting dynamics using the minirhizotron technique is useful for cultivar selection and to quantify nematode damage to roots. A 2-yr microplot study including five bermudagrass (‘Tifway’, Belonolaimus longicaudatus susceptible; two commercial cultivars [TifSport and Celebration] and two genotypes [‘BA132’ and ‘PI 291590’], which have been reported to be tolerant to B. longicaudatus) and two St. Augustinegrass (‘FX 313’, susceptible, and ‘Floratam’ that was reported as tolerant to B. longicaudatus) genotypes in a 5 x 2 and 2 x 2 factorial design with four replications, respectively, was initiated in 2012. Two treatments included were uninoculated and B. longicaudatus inoculated. In situ root images were captured each month using a minirhizotron camera system from April to September of 2013 and 2014. Mixed models analysis and comparison of least squares means indicated significant differences in root parameters studied across the genotypes and soil depths of both grass species. ‘Celebration’, ‘TifSport’ and ‘PI 291590’ bermudagrass, and ‘Floratam’ St. Augustinegrass had significantly different root parameters compared to the corresponding susceptible genotypes (P ≤ 0.05). Only ‘TifSport’ had no significant root loss when infested with B. longicaudatus compared to non-infested. ‘Celebration’ and ‘PI 291590’ had significant root loss but retained significantly greater root densities than ‘Tifway’ in B. longicaudatus-infested conditions (P ≤ 0.05). Root lengths were greater at the 0 to 5 cm depth followed by 5 to 10 and 10 to 15 cm of vertical soil depth for both grass species (P ≤ 0.05). ‘Celebration’, ‘TifSport’, and ‘PI 291590’ had better root vigor against B. longicaudatus compared to Tifway.  相似文献   
77.
Despite the widespread use of kinase-targeted agents in clear cell renal cell carcinoma (CC-RCC), comprehensive kinase activity evaluation (kinomic profiling) of these tumors is lacking. Thus, kinomic profiling of CC-RCC may assist in devising a classification system associated with clinical outcomes, and help identify potential therapeutic targets. Fresh frozen CC-RCC tumor lysates from 41 clinically annotated patients who had localized disease at diagnosis were kinomically profiled using the PamStation®12 high-content phospho-peptide substrate microarray system (PamGene International). Twelve of these patients also had matched normal kidneys available that were also profiled. Unsupervised hierarchical clustering and supervised comparisons based on tumor vs. normal kidney and clinical outcome (tumor recurrence) were performed and coupled with advanced network modeling and upstream kinase prediction methods. Unsupervised clustering analysis of localized CC-RCC tumors identified 3 major kinomic groups associated with inflammation (A), translation initiation (B), and immune response and cell adhesions (C) processes. Potential driver kinases implicated include PFTAIRE (PFTK1), PKG1, and SRC, which were identified in groups A, B, and C, respectively. Of the 9 patients who had tumor recurrence, only one was found in Group B. Supervised analysis showed decreased kinase activity of CDK1 and RSK1-4 substrates in those which progressed compared to others. Twelve tumors with matching normal renal tissue implicated increased PIM’s and MAPKAPK’s in tumors compared to adjacent normal renal tissue. As such, comprehensive kinase profiling of CC-RCC tumors could provide a functional classification strategy for patients with localized disease and identify potential therapeutic targets.  相似文献   
78.
Cryptococcus neoformans is an important fungal pathogen of man. The incidence of cryptococcal disease has increased dramatically in patients immunocompromised because of HIV infection, organ transplantation, or treatment with cytotoxic chemotherapy or corticosteroids. This organism is an excellent model for molecular dissection of fungal pathogenesis and virulence factors. Here we report the nucleotide sequence of the C. neoformans serotype D genomic ADE2 gene, which encodes a phosphoribosylaminoimidazole carboxylase required for purine biosynthesis. Importantly, this version of the ADE2 gene has been used as the selectable marker for virtually all gene disruptions by transformation and homologous recombination in C. neoformans. We compare the nucleotide and amino acid sequences of the ADE2 gene and product to other highly related adenine biosynthetic genes and enzymes from other yeasts and fungi. We also describe a series of convenient ADE2 cassettes for gene disruption construct preparation. Finally, we have identified the ade2 mutations in strains M001 and M049, adenine auxotrophic mutants derived from the serotype A strain H99. These mutant strains have served as recipients for targeted gene disruptions using the ADE2 gene. These studies should facilitate transformation and gene disruption approaches using the ADE2 selectable marker in this important human fungal pathogen.  相似文献   
79.
The stoichiometric analysis of the metal induced Metallothionein (MT) is pertinent for understanding the metal-MT interactions. Despite innumerable publications on MT, the literature addressing these aspects is limited. To bridge this gap, PIXE and ESI-MS analysis of the commercial rabbit liver MT1 (an isoform of MT), zinc induced isolated rat liver MT1, apo and Arsenic substituted rabbit liver MT1 have been carried out. These techniques in combination provide information about number and the signature of all the metal ions bound to MT. By using ESI-MS in the rabbit MT1, ions of Zn n MT1 (n = 0, 1, 4, 5, 6, 7) whereas, in rat MT1, the Zn1MT1 and Zn5MT1 ions are observed. PIXE analysis shows that some copper along with zinc is also present in the rabbit as well as rat MT1 which could not be assessed with ESI-MS. During As metallation reaction with rabbit MT1, with increase in arsenic concentration, the amount of arsenic bound to MT1 also increases, though not proportionally. The presence of both Zn and Cu in MT1 on Zn supplementation can be related to the role of MT in Zn and Cu homeostasis. Further, the presence of partially metallated MT1 suggests that MT1 may donate fractional amount of metal from it’s fully metallated form to other proteins where Zn acts as a cofactor.  相似文献   
80.
This work describes the utility of Bsmoc group in the synthesis of ureidopeptides and peptidyl ureas. The reaction of isocyanates derived from Bsmoc-α-amino acids with amino acid ester has yielded the ureidopeptides in good yields. The isocyanates were obtained by subjecting Bsmoc-amino acid azides to Curtius rearrangement. Bsmoc protected ureidopeptides have been isolated as solids and characterized by 1H NMR, 13C NMR and mass spectrum.  相似文献   
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