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Applied Microbiology and Biotechnology - The objective of this study was to identify and exploit a robust biocatalyst that can be applied in reductive amination for enantioselective synthesis of... 相似文献
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Cindy H. Wu Thomas K. Wood Ashok Mulchandani Wilfred Chen 《Applied microbiology》2006,72(2):1129-1134
The use of plants for rehabilitation of heavy-metal-contaminated environments is an emerging area of interest because it provides an ecologically sound and safe method for restoration and remediation. Although a number of plant species are capable of hyperaccumulation of heavy metals, the technology is not applicable for remediating sites with multiple contaminants. A clever solution is to combine the advantages of microbe-plant symbiosis within the plant rhizosphere into an effective cleanup technology. We demonstrated that expression of a metal-binding peptide (EC20) in a rhizobacterium, Pseudomonas putida 06909, not only improved cadmium binding but also alleviated the cellular toxicity of cadmium. More importantly, inoculation of sunflower roots with the engineered rhizobacterium resulted in a marked decrease in cadmium phytotoxicity and a 40% increase in cadmium accumulation in the plant root. Owing to the significantly improved growth characteristics of both the rhizobacterium and plant, the use of EC20-expressing P. putida endowed with organic-degrading capabilities may be a promising strategy to remediate mixed organic-metal-contaminated sites. 相似文献
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To study the effects of different durations of forward masker sound on neuronal firing and rate-intensity function (RIF) of
mouse inferior collicular (IC) neurons, a tone relative to 5 dB above the minimum threshold (re MT+5 dB) of the best frequency
of recorded neurons was used as forward masker sound under free field stimulation condition. The masker durations used were
40, 60, 80, and 100 ms. Results showed that as masker duration was increased, inhibition in neuronal firing was enhanced (P < 0.000 1, n = 41) and the latency of neurons was lengthened (P<0.01, n = 41). In addition, among 41 inhibited IC neurons, 90.2% (37/41) exhibited narrowed dynamic range (DR) when masker sound
duration was increased (P < 0.000 1), whereas the DR of 9.8%(4/41) became wider. These data suggest that masking effects of different durations of
forward masker sound might be correlated with the amplitude and duration of inhibitory input to IC neurons elicited by the
masker sound.
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Translated from Journal of Central China Normal University (Nat. Sci.), 2005, 39(2): 236–240 [译自: 华中师范大学学报 (自然科学版), 2005, 39(2): 236–240] 相似文献