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1.
2.
The model conjugates phycocyanin-allophycocyanin (C-PC-APC) and phycoerythrocyanin-phycocyanin-allophycocyanin (PEC-C-PC-APC)
were synthesized by using a heterobifunctional coupling reagent N-succinimidyl-3-(2-pyridyldithio)propionate. The rod-core
complex (αβ)6
PCLRC
27(αβ)3
APCLC
8.9 and phycobilisomes were separated from Anabaena variabilis. Energy transfer features for the conjugates and the complexes
were compared. The absorption and fluorescence emission spectra indicated that the linker-peptides mediate interaction of
phycobiliproteins and prompt energy transfer. The energy transfer in the conjugates was detected by fluorescence emission
spectra and confirmed by the addition of dithiothreitol. The conjugates may be used as models for studying the energy transfer
mechanism in phycobilisomes.
This revised version was published online in September 2006 with corrections to the Cover Date. 相似文献
3.
Ahmed H.E. Hassan Min Chang Cho Hye In Kim Ji Seul Yang Kyung Tae Park Ji Young Hwang Choon-Gon Jang Ki Duk Park Yong Sup Lee 《Bioorganic & medicinal chemistry》2018,26(18):5069-5078
CRA13; a peripheral dual CB1R/CB2R agonist with clinically proven analgesic properties, infiltrates into CNS producing adverse effects due to central CB1R agonism. Such adverse effects might be circumvented by less lipophilic compounds with attenuated CB1R affinity. Metabolism produces less lipophilic metabolites that might be active metabolites. Some CRA13 oxidative metabolites and their analogues were synthesized as less lipophilic CRA13 analogues. Probing their CB1R and CB2R activity revealed the alcohol metabolite 8c as a more potent and more effective CB2R ligand with attenuated CB1R affinity relative to CRA13. Also, the alcohol analogue 8b and methyl ester 12a possessed enhanced CB2R affinity and reduced CB1R affinity. The CB2R binding affinity of alcohol analogue 8b was similar to CRA13 while that of methyl ester 12a was more potent. In silico study provided insights into the possible molecular interactions that might explain the difference in the elicited biological activity of these compounds. 相似文献
4.
Phenyllactic acid (PLA) is a novel antimicrobial compound derived from phenylalanine (Phe). Lactobacillus sp. SK007, having high PLA-producing ability, was isolated from Chinese traditional pickles. When 6.1 mM phenylpyruvic acid
(PPA) was used to replace Phe as substrate at the same concentration, PLA production increased 14-fold and the fermentation
time decreased from 72 h to 24 h with growing cells. With resting cells, however, 6.8 mM PLA could be obtained as optimal
yield using the following conditions: 12 mM PPA, 55 mM glucose, pH 7.5, 35°C and 4 h. 相似文献
5.
The elevated concentration of atmospheric CO2 may result in a decline of leaf nutritional quality (especially N) and an increase in some kinds of defensive secondary components
(such as phenolics). The changes in the phytochemistry of trees, combined with the effect of elevated CO2
per se, have a potential negative influence on insect herbivores. Here, we review the effect of elevated CO2 on the performance of leaffeeding forest insects at individual-level and community-level. The elevated CO2
per se have little influence on the metabolism of insects. Over half of the tree-insect experimental systems show that the performance
of individual insect become poorer under high-CO2 grown trees; but the others show that the insects have just little or no response to the treatments. The direction and magnitude
of the changes in the performance of insects could be mediated by various factors. The effects of treatment are strongly species-dependent.
The magnitude of changes in the phytochemistry, the sensitivity and adaptive capacity of insects to the poorer leaf quality,
the differences in plant growth conditions and experimental methods, and the mediated effects of other environmental factors
(such as soil nutrient availability, light, temperature, O3) were all closely related to the final performance of insects. However, the larvae’s consumption usually increased under
enriched CO2 treatment, which was widely thought to be a compensatory response to poorer plant quality. The experiments on forest community-level
found identically a reduction in herbivory, which was contrary to the results from small-scale experiments. The changes in
insect population and the actual response of consumption by leaf-feeding forest insects under CO2 enrichment remain unclear, and more field-based experiments need to be conducted.
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Translated from Chinese Journal of Applied Ecology, 2006, 17(4): 720–726 [译自: 应用生态学报] 相似文献
6.
7.
腹腔注射链脲佐霉素(65mg/kg)诱发Wistar大鼠糖尿病。糖尿病发病4周后,向饲料中加尼群地平(30mg·kg-1·d-1)。结果表明,糖尿病4周时大鼠心室舒张功能首先受损,8周后心室舒张和收缩功能均明显受累。尼群地平处理对糖尿病大鼠的心肌收缩性有一定的改善作用。提示尼群地平对大鼠糖尿病性心肌病有一定有益作用。 相似文献
8.
9.
10.
Zhongyuan Liu Yun Wang Guodong Lü Xianlei Wang Fuchun Zhang Ji Ma 《Frontiers of Biology in China》2008,3(3):279-286
Partial cDNA sequences coding for antifreeze proteins in Tenebrio molitor were obtained by RT-PCR. Sequence analysis revealed nine putative cDNAs with a high degree of homology to Tenebrio molitor antifreeze protein genes published in GenBank. The recombinant pGEX-4T-1-tmafp-XJ430 was introduced into E. coli BL21 to induce a GST fusion protein by IPTG. SDSPAGE analysis for the fusion protein shows a band of 38 kDa. pCDNA3-tmafp-XJ430 was injected into mice to generate antiserum which was later detected by indirect ELISA. The titer of the antibody
was 1:2000.Western blotting analysis shows that the antiserum was specifically against the antifreeze protein. Our results
laid the foundation for further studies on the properties and functions of insect antifreeze proteins.
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Translated from Hereditas (Beijing), 2006, 28(12): 1532-1540 [译自: 遗传] 相似文献