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71.
Mei‐Hong Yang Hong‐Xia Liu Jin‐Long Liu Xiao‐Yuan Jing Jin‐Tong Zhang Li‐Hua Fan Shi‐Fei Wang 《Entomologia Experimentalis et Applicata》2015,154(3):199-205
Extracts of the female sex pheromone gland of the carpenterworm moth, Holcocerus vicarius (Walker) (Lepidoptera: Cossidae), a pest of Ulmus pumila L. (Ulmaceae), were found to contain Z7‐tetradecenyl acetate (Z7‐14Ac), E3‐tetradecenyl acetate (E3‐14Ac), (Z3,E5)‐tetradecenyl acetate (Z3,E5‐14Ac), and Z7‐tetradecenyl alcohol (Z7‐14OH) by coupled gas chromatographic‐electroantennographic detection (GC‐EAD) and coupled gas chromatography‐mass spectrometry (GC‐MS). Field trapping studies with impregnated rubber septa indicated that Z7‐14Ac was essential for attraction of males of H. vicarius. However, the most attractive blend contained Z7‐14Ac, E3‐14Ac, Z3,E5‐14Ac, and Z7‐14OH in a 50:22:17:10 ratio. Our results demonstrated that a blend of Z7‐14Ac, E3‐14Ac, Z3,E5‐14Ac, and Z7‐14OH represented the sex pheromone of H. vicarius. The optimized four‐component lure blend may be useful for monitoring H. vicarius infestations and mating disruption. 相似文献
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74.
Marc‐André Dubois Alain Grandbois Shawn K. Collins Andreea R. Schmitzer 《Journal of molecular recognition : JMR》2011,24(2):288-294
Dimerization of a hydroxycarbazole produces an axially chiral biaryl, BICOL ( 2 ). One enantiomer (R)‐ 2 , is capable of enantioselective binding to different polymorphs of DNA. The biaryl (R)‐ 2 was shown by fluorescence and circular dichroism to induce a shift of Z‐DNA to B‐DNA. The opposite enantiomer (S)‐ 2 shows no specific binding. The significant difference in behaviour between the two enantiomers (S)‐ 2 and (R)‐ 2 is in line with molecular modelling studies which show two very different binding geometries between the enantiomers with each polymorph of DNA. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
75.
Prakash M. Davadra Batuk Dabhi Manoj K. Singh Mukul R. Jain Hitendra S. Joshi Atul H. Bapodra 《Chirality》2011,23(10):955-960
A reverse phase high performance liquid chromatography (HPLC) method has been developed for the separation of two geometric isomers of Acrivastine using crude reaction mixture. The resolution between two isomers was found more than 2.9. The geometric isomers have been isolated by preparative HPLC and characterized by spectroscopic techniques, such as NMR, infrared, and MS. The developed method has been validated for the determination of Z‐isomer in Acrivastine. The limit of detection and limit of quantification of the Z‐isomer were 0.05 and 0.2 μg/ml, respectively. The developed method is precise, linear, accurate, rugged and robust for its intended use. Chirality, 2011. © 2011 Wiley‐Liss, Inc. 相似文献
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已测序的微生物基因组中包含的注释开放阅读框(open reading frames,ORFs)可以分为两大类:第一类对应于功能已知的蛋白质编码基因;第二类则为功能未知的假设ORFs,其中通常有一部分实际上不编码蛋白质。采用基于Z曲线的方法从属于第一类的功能已知基因出发训练参数,进而确定第二类ORFs中非编码的部分。通过支持向量机的学习及分类,结果显示十重交叉检验平均正确率为98.45%,说明Z曲线联合支持向量机是一种高度准确的基因识别方法。最终,确定216个假设ORFs实际上不编码蛋白质。通过采用Blastp进行序列比对,保留的假设ORFs中有341个在高可靠性的条件下获得了功能信息。根据蛋白质直系同源簇方法进行功能分类,分别有30、53、59和159个新注释的假设ORFs属于信息储存和加工类、细胞加工和信号传递类、新陈代谢类和特征不明显类。另外还有70个不属于其中的任何一类。注释结果比RefSeq及GenBank提供的原注释更加准确,更加完整。 相似文献
78.
N-Glycosylation of many glycoprotein drugs is important for biological activity and should therefore be the target of specific and quantitative analytical methods. In this study, we focus on the two N-glycan mapping approaches that are used in pharmacopoeial monograph to analyse N-glycans released from fifteen preparations of recombinant human erythropoietin supplied by ten Chinese manufacturers. Underivatised N-glycans were analysed by high performance anion-exchange chromatography with pulsed amperometric detection and fluorophore-labelled N-glycans were analysed by weak anion-exchange and normal-phase high performance liquid chromatography. N-glycans were also analysed by matrix assisted laser desorption ionisation mass spectrometry. The release of N-glycans by PNGase F was shown to be consistent. Z number, a mathematical expression of the total negatively charged N-glycans composition has provided a convenient way to summarise the complex dataset and it might be suitable for product consistency monitoring. However, this Z number reduces the information of individual acidic N-glycan structure and is also found to be method dependent. Therefore, its use requires clear specification and validation. In this study, we only found weak but positive correlation between the Z number and its bioactivity. Wide range of N-glycans yields were obtained from the fifteen preparations but the significance of their differences is unclear. 相似文献
79.
Peter Järver Cecilia Mikaelsson Amelie Eriksson Karlström 《Journal of peptide science》2011,17(6):463-469
The Z‐molecule is a small, engineered IgG‐binding affinity protein derived from the immunoglobulin‐binding domain B of Staphylococcus aureus protein A. The Z‐domain consists of 58 amino acids forming a well‐defined antiparallel three‐helix structure. Two of the three helices are involved in ligand binding, whereas the third helix provides structural support to the three‐helix bundle. The small size and the stable three‐helix structure are two attractive properties comprised in the Z‐domain, but a further reduction in size of the protein is valuable for several reasons. Reduction in size facilitates synthetic production of any protein‐based molecule, which is beneficial from an economical viewpoint. In addition, a smaller protein is easier to manipulate through chemical modifications. By omitting the third stabilizing helix from the Z‐domain and joining the N‐ and C‐termini by a native peptide bond, the affinity protein obtains the advantageous properties of a smaller scaffold and in addition becomes resistant to exoproteases. We here demonstrate the synthesis and evaluation of a novel cyclic two‐helix Z‐domain. The molecule has retained affinity for its target protein, is resistant to heat treatment, and lacks both N‐ and C‐termini. Copyright © 2011 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
80.
Kawamori A Ono TA Ishii A Nakazawa S Hara H Tomo T Minagawa J Bittl R Dzuba SA 《Photosynthesis research》2005,84(1-3):187-192
The functional site of ChlZ, an auxiliary electron donor to P680+, was determined by pulsed ELDOR applied to a radical pair of YD• and Chlz+ in oriented PS II membranes from spinach. The radical-radical distance was determined to be 29.5 Å and its direction was 50° from the membrane normal, indicating that a chlorophyll on the D2 protein is responsible for the EPR Chlz+ signal. Spin polarized ESEEM (Electronin Spin Echo Envelop Modulation) of a 3Chl and QA− radical pair induced by a laser flash was observed in reaction center D1D2Cytb559 complex, in which QA was functionally reconstituted with DBMIB and reduced chemically. QA−ESEEM showed a characteristic oscillating time profile due to dipolar coupling with 3Chl. By fitting with the dipolar interaction parameters, the distance between 3Chl and QA− was determined to be 25.9 Å, indicating that the accessory chlorophyll on the D1 protein is responsible for the 3Chl signal. 相似文献