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31.
Abstract Extracts of hairpencils ffom male cotton bollworm moth were analyzed by capillary gas chromatography, acid methanolysis, and GC-MS. Ten components have been identified as: 14; OH, 14: Ac, 14: COOH, 211–16: OH, 16: OH, 16: Ac, 16: COOH, 18: OH, 18: Ac, and 18: COOH. Based on the statistics of titer of each chemical, the total amount of three saturated alcohols is over 75%. The amounts of the chemicals in the hairpencils are related to the age of males. There are no chemicals identified in the extracts from males less than 10 h after eclosion, then the quantity of compounds increased rapidly during 48 h after adult eclosion. After 5 days, the quantity decreased. 相似文献
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Yu Bofan Liu Yang Liu Jia Guo Xiaorui Tang Zhonghua 《Journal of Plant Growth Regulation》2022,41(6):2093-2107
Journal of Plant Growth Regulation - In plants, apical hook opening is critical for the post-germination stage and subsequent photomorphogenesis, and this process is activated by a luminous... 相似文献
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为研究鸭C4结合蛋白(C4b-binding protein,C4BP)与鸭疫里默氏菌(Riemerella anatipestifer,RA)的相互作用,对鸭C4BPα进行克隆、原核表达,免疫小鼠制备多克隆抗体,并利用间接免疫荧光试验及斑点杂交试验验证C4BP与RA的相互作用。结果显示,鸭C4BPα核苷酸序列全长为1230bp,与鸡C4BPα的相似性最高(82.1%);系统进化树分析发现,鸭C4BPα与鸡C4BPα处于同一系统进化树分支上,两者遗传进化关系最近;C4BPα在大肠杆菌Escherichia coli BL21 (DE3)中能高效表达,重组蛋白以胞内可溶性形式存在;多克隆抗体效价超过1∶10000,并且可以与重组蛋白发生特异性反应;间接免疫荧光试验和斑点杂交试验结果显示RA与鸭C4BP可以发生相互作用。研究结果为进一步揭示RA的致病机制奠定了基础。 相似文献
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Erju Tang Xiaolin Shen Jia Wang Xinxiao Sun Qipeng Yuan 《Biotechnology and bioengineering》2020,117(4):1247-1252
myo-Inositol (MI) as a dietary supplement can provide various health benefits. One major challenge to its efficient biosynthesis is to achieve proper distribution of carbon flux between growth and production. Herein, this challenge was overcome by synergetic utilization of glucose and glycerol. Specifically, glycerol was catabolized to support cell growth while glucose was conserved as the building block for MI production. Growth and production were coupled via the phosphotransferase system, and both modules were optimized to achieve efficient production. First, the optimal enzyme combination was established for the production module. It was observed that enhancing the production module resulted in both increased MI production and better cell growth. In addition, glucose was shown to inhibit glycerol utilization via carbon catabolite repression and the inhibition was released by over-expressing glycerol kinase. Furthermore, the inducible promoter was replaced by strong constitutive promoters to avoid inducer use. With these efforts, the final strain produced MI with both high titer and yield. In fed-batch cultivation, 76 g/L of MI was produced, showing scale-up potential. This study provides a promising strategy to achieve rational distribution of carbon flux. 相似文献
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Tian Wei Han Xiao-Guang Liu Ya-Jun Tang Guo-Qing Liu Bo Wang Yong-Qing Xiao Bin Xu Yun-Feng 《Neurochemical research》2020,45(7):1729-1730
Neurochemical Research - Since the publication of our article [1] it has come to our attention that there was an error in Figure 4 in which the bottom left immunochemistry panel Control/Bax was a... 相似文献
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The 14-3-3 proteins are a highly conserved family of homodimeric and heterodimeric molecules, expressed in all eukaryotic cells. In human cells, this family consists of seven distinct but highly homologous 14-3-3 isoforms. 14-3-3σ is the only isoform directly linked to cancer in epithelial cells, which is regulated by major tumor suppressor genes. For each 14-3-3 isoform, we have 1,000 peptide motifs with experimental binding affinity values. In this paper, we present a novel method for identifying peptide motifs binding to 14-3-3σ isoform. First, we propose a sampling criteria to build a predictor for each new peptide sequence. Then, we select nine physicochemical properties of amino acids to describe each peptide motif. We also use auto-cross covariance to extract correlative properties of amino acids in any two positions. Finally, we consider elastic net to predict affinity values of peptide motifs, based on ridge regression and least absolute shrinkage and selection operator (LASSO). Our method tests on the 1,000 known peptide motifs binding to seven 14-3-3 isoforms. On the 14-3-3σ isoform, our method has overall pearson-product-moment correlation coefficient (PCC) and root mean squared error (RMSE) values of 0.84 and 252.31 for N–terminal sublibrary, and 0.77 and 269.13 for C–terminal sublibrary. We predict affinity values of 16,000 peptide sequences and relative binding ability across six permutated positions similar with experimental values. We identify phosphopeptides that preferentially bind to 14-3-3σ over other isoforms. Several positions on peptide motifs are in the same amino acid category with experimental substrate specificity of phosphopeptides binding to 14-3-3σ. Our method is fast and reliable and is a general computational method that can be used in peptide-protein binding identification in proteomics research. 相似文献
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