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251.
Ding Q Dimayuga E Martin S Bruce-Keller AJ Nukala V Cuervo AM Keller JN 《Journal of neurochemistry》2003,86(2):489-497
Increasing evidence suggests that proteasome inhibition plays a causal role in promoting the neurodegeneration and neuron death observed in multiple disorders, including Alzheimer's disease (AD) and Parkinson's disease (PD). The ability of severe and acute inhibition of proteasome function to induce neuron death and neuropathology similar to that observed in AD and PD is well documented. However, at present the effects of chronic low-level proteasome inhibition on neural homeostasis has not been elucidated. In order to determine the effects of chronic low-level proteasome inhibition on neural homeostasis, we conducted studies in individual colonies of neural SH-SY5Y cells that were isolated following continual exposure to low concentrations (100 nm) of the proteasome inhibitor MG115. Clonal cell lines appeared morphologically similar to control cultures but exhibited significantly different rates of both proliferation and differentiation. Elevated levels of protein oxidation and protein insolubility were observed in clonal cell lines, with all clonal cell lines being more resistant to neural death induced by serum withdrawal and oxidative stress. Interestingly, clonal cell lines demonstrated evidence for increased macroautophagy, suggesting that chronic low-level proteasome inhibition may cause an excessive activation of the lysosomal system. Taken together, these data indicate that chronic low-level proteasome inhibition has multiple effects on neural homeostasis, and suggests that studying the effects of chronic low-level proteasome inhibition may be useful in understanding the relationship between protein oxidation, protein insolubility, proteasome function, macroautophagy and neural viability in AD and PD. 相似文献
252.
A hyperperformer for the production of verbenol was produced from the fusion of two improved strains of Aspergillus niger. A 2-deoxy glucose de-repressed mutant [high sporulation (50%), viability (80%) showing a conversion of 15.6% of initial alpha-pinene to verbenol in 6 h under the conditions used] was fused with another strain enriched with alpha-pinene (26.4% of alpha pinene converted to verbenol) to obtain a final verbenol conversion yield of 48.6% of initial alpha pinene. 相似文献
253.
Twenty soil communities from the northeastern forests (Assam) and the Western Ghats (Maharashtra) were screened for the presence
of the lysine aminotransferase (lat) gene fromNocardia. Hybridization probes and primers were synthesized in accordance with the reported sequence of theNocardia lat gene from GenBank (number: G1 49355). Seven positives were obtained from the 20 soils. Six of the seven positive were from
the Western Ghats and one from the northeast Assam forests. Eighteen actinomycete isolates from the 7 positive soils showed
the presence of thelat gene. Only 9 isolates actually produced an antibiotic. These results are discussed. 相似文献
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Photosynthetic characteristics of peanut genotypes under excess and deficit irrigation during summer
Kalariya Kuldeepsingh A. Singh Amrit Lal Goswami Nisha Mehta Deepti Mahatma Mahesh Kumar Ajay B. C. Chakraborty Koushik Zala P. V. Chaudhary Vidya Patel C. B. 《Physiology and Molecular Biology of Plants》2015,21(3):317-327
Physiology and Molecular Biology of Plants - In a field experiment three irrigation treatments were given to twelve peanut genotypes through drip. At 80 days after sowing (DAS) the amount... 相似文献
256.
ABSTRACT Soil heavy metal contamination, a major threat due to industrialization, can be tackled by an efficient and economical process called bioremediation. Mushrooms are employed to accumulate heavy metals from soil due to their high metal accumulation potential and better adaptability. The bioaccumulation potential of Galerina vittiformis was already reported for individual metals. At natural conditions, since soil consists of more than one polluting metal, more focus has to be given to multimetal systems. In this study, multimetal accumulation potential was analyzed using central composite design, and the responses obtained were analyzed using response surface methodology. Heavy metals such as Cu(II), Cd(II), Cr(VI), Pb(II), and Zn(II) were subjected to biosorption at 10–250 mg/kg concentrations along with pH 5–8. The results showed that the preference of the organism for the five metals under study was in the order Pb(II) > Zn(II) > Cd(II) > Cu(II) > Cr(VI) at pH 6.5 under multimetal condition. The study also indicates that the metal interaction pattern in multimetal interaction is a property of their ionic radii. The response surface methodology clearly explains the effect of interaction of heavy metals on the accumulation potential of the organism using three-dimensional response plots. The present work suggests that the fungus Galerina vittiformis could be employed as a low-cost metal removal agent from heavy metal–polluted soil. 相似文献
257.
Vidya Sagar Narottam P. Sahu Asim K. Pal Mohamed Hassaan Kamal K. Jain Heba S. Salim Vikas Kumar Ehab R. El‐Haroun 《Zeitschrift fur angewandte Ichthyologie》2019,35(4):1016-1024
A feeding trial was conducted to study the effect of dietary protein (DP) levels on the enzyme activities of different stocks of Macrobrachium rosenbergii juveniles, fed two diets prawn type diets either at optimum (ODP, 32%) or sub‐optimum (SDP, 27%) dietary protein. The activity of key enzymes: glycolysis, gluconeogenesis, amino acid catabolism, pentose phosphate pathway, and energy metabolism was examined on different stocks of M. rosenbergii juveniles in various tissues (muscle, hepatopancreas, and gill). Wild juveniles of M. rosenbergii were collected from the west coast of India, Gujarat (G), Maharashtra (M) and from the east coast of India, Andhra Pradesh (A), and raised in culture ponds of 200 m2 at 1 juvenile m‐2. The experiment was conducted for a period of 60 days. A Visible Implant Elastomer (VIE) Tag was injected into different prawn juveniles’ stocks A, (3.06–3.10 g), M, (0.80–1.01 g) and G (0.90–1.06 g) for the individual identification of each class. All the animals were acclimatized for 7 days before being released into the pond. Each of the two diets, the first with 27% SDP, termed the sub‐optimum level (S), and the second 32% DP, termed the optimum level (O), was fed in triplicate ponds. The weight gain of stocked prawn was significantly higher for G stock (3.03 ± 0.18 g) compared to M stock (2.53 ± 0.25 g) and A stock (1.33 ± 0.10 g). In addition weight gain in ODP was significantly higher (3.05 ± 0.22 g) compared to SDP (2.11 ± 0.17 g). Furthermore, both protein level and stock type had a significant (p ≤ 0.05) effect on the survival rate, specific growth rate, and feed conversion ratio of the prawn. A significant interaction was recorded between metabolic enzyme activities and the variation of dietary protein levels and differences in M. rosenbergii stocks, in which stock “G” and “M” exhibited healthier enzyme physiological status than stock “A”. The findings presented here may conclude that the enzymes quickly respond to dietary protein manipulations of cultured shrimp. The results can be useful in identifying the optimum stock (genotypes) in a given culture condition and subsequently higher production may be achieved. 相似文献
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