The need for designers and users of pesticide application equipment to balance the risk of off-target contamination with high product efficacies when using the minimum dose of active ingredient has led to the requirem...
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The plastid genome is transcribed by three different RNA polymerases, one is called plastid- encoded RNA polymerase (PEP) and two are called nucleus- encoded RNA polymerases (NEPs). PEP transcribes preferentially phot...
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The plastid genome is transcribed by three different RNA polymerases, one is called plastid- encoded RNA polymerase (PEP) and two are called nucleus- encoded RNA polymerases (NEPs). PEP transcribes preferentially photosynthesis- related genes in mature chloroplasts while NEP transcribes preferentially housekeeping genes during early phases of plant development, and it was generally thought that during plastid differentiation the building up of the NEP transcription system precedes the building up of the PEP transcription system. We have now analyzed in detail the establishment of the two different transcription systems, NEP and PEP, during germination and early seedling development on the mRNA and protein level. Experiments have been performed with two different plant species, Arabidopsis (Arabidopsis thaliana) and spinach (Spinacia oleracea). Results show that the building up of the two different transcription systems is different in the two species. However, in both species NEP as well as PEP are already present in seeds, and results using Tagetin as a specific inhibitor of PEP activity demonstrate that PEP is important for efficient germination, i.e. PEP is already active in not yet photosynthetically active seed plastids.
The application of aqueous two-phase systems (ATPS) to bioseparation and biocatalyst engineering has attracted interest. However, despite the distinct advantages of the technique, the scaling up of ATPS is limited by ...
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The application of aqueous two-phase systems (ATPS) to bioseparation and biocatalyst engineering has attracted interest. However, despite the distinct advantages of the technique, the scaling up of ATPS is limited by the cost of the system components. In this study, two novel recyclable pH-responsive polymers were synthesized and tested for the partition of demeclocycline. The recoveries of two recyclable *** polymers could reach over 95.0% by only adjusting the solution pH to the isoelectric points of the polymers. The control variate method was used to investigate the effects of polymerization conditions on polymer synthesis. Polymer P-ADB4.6 was firstly synthesized in 5001 reactor with two-stage heating method (25-40 degrees C and 40-62 degrees C), as the heating rate is an important factor in the scale-up process. The polymer characteristics (molecular weight, viscosity, surface tension, and zeta potential) were studied to understand their influences on the synthetic process. Furthermore, the phase formation mechanism was studied with low-field nuclear magnetic resonance (LF-NMR). The optimal partition coefficient and recovery of demeclocycline using the recyclable ATPS were 0.24 and 82.9% at pH 6.30 in presence of 20 mmol/L MgSO4.
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