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Shuen‐Fang Lo Ien‐Chie Wen Yi‐Lun Liu Ku‐Ting Chen Mirng‐Jier Jiang Ming‐Kuang Lin Meng‐Yen Rao Lin‐Chih Yu Tuan‐Hua David Ho Su‐May Yu 《Plant, cell & environment》2016,39(5):998-1013
Rice is an important crop and major model plant for monocot functional genomics studies. With the establishment of various genetic resources for rice genomics, the next challenge is to systematically assign functions to predicted genes in the rice genome. Compared with the robustness of genome sequencing and bioinformatics techniques, progress in understanding the function of rice genes has lagged, hampering the utilization of rice genes for cereal crop improvement. The use of transfer DNA (T‐DNA) insertional mutagenesis offers the advantage of uniform distribution throughout the rice genome, but preferentially in gene‐rich regions, resulting in direct gene knockout or activation of genes within 20–30 kb up‐ and downstream of the T‐DNA insertion site and high gene tagging efficiency. Here, we summarize the recent progress in functional genomics using the T‐DNA‐tagged rice mutant population. We also discuss important features of T‐DNA activation‐ and knockout‐tagging and promoter‐trapping of the rice genome in relation to mutant and candidate gene characterizations and how to more efficiently utilize rice mutant populations and datasets for high‐throughput functional genomics and phenomics studies by forward and reverse genetics approaches. These studies may facilitate the translation of rice functional genomics research to improvements of rice and other cereal crops. 相似文献
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Dawei Jiang Yunchao Liu Aiping Wang Gaiping Zhang Guoyu Yang Yumei Chen Pengchao Ji Chang Liu Yapeng Song Yunfang Su Guoqiang Wang Jucai Wang Baolei Zhao Ruiguang Deng 《Biotechnology letters》2016,38(6):901-908
Objectives
To improve the expression of soluble IBDV VP2 protein by using different tagged vectors in Escherichia coli.Results
Fusion tags, Grifin, MBP, SUMO, thioredoxin, γ-crystallin, ArsC and PpiB, enhanced the expression and solubility of VP2 protein. The fusion proteins were purified by Ni–NTA chromatography, MBP-VP2 showed the highest purity about 90 %. After removing the MBP tag, VP2 self-assembled into virus-like particles, ~25 nm diam. Results from AGP suggested the recombinant IBDV VP2 protein identified by reference serum like IBDV.Conclusion
All the seven tags enhanced the expression and solubility of IBDV VP2 protein. The recombinant protein self-assembly into virus like particles and possess antigenicity as reference IBDV.965.
966.
Xiaobo Dong Haiyun Li Yucheng Jiang Mancheng Hu Shuni Li Quanguo Zhai 《Biotechnology letters》2016,38(9):1483-1491
Objectives
To degrade enzymatically bisphenol A (BPA) that causes serious environmental concerns and is difficult to be degraded by chemical or physical methods.Results
BPA (150 mg l?1) was completely degraded by chloroperoxidase (CPO)/H2O2 within 7 min at room temperature, atmospheric pressure with the enzyme at 6 μg CPO ml?1. The degradation products were identified by HPLC–MS, which suggested involvement of multiple steps. Enzymatic treatment followed by existing bioremediation technologies (activated sludge) enhanced removal of COD from 9 to 54 %. Using an ecotoxicity evaluation with Chlorella pyrenoidosa, the degradation products had a lower toxicity than BPA.Conclusion
BPA can be degraded rapidly and efficiently under mild conditions with chloroperoxidase at 6 μg ml?1. The degradation products had a lower toxicity than BPA.967.
Xiaojie Duan Mingming Zheng Yu Liu Zhengqiang Jiang Shaoqing Yang 《Biotechnology letters》2016,38(12):2127-2135
Objectives
To identify novel cold-active lipases from fungal sources and improve their production by heterologous expression in Pichia pastoris.Results
A novel cold-active lipase gene (ReLipB) from Rhizomucor endophyticus was cloned. ReLipB was expressed at a high level in Pichia pastoris using high cell-density fermentation in a 5-l fermentor with the highest lipase activity of 1395 U/ml. The recombinant lipase (RelipB) was purified and biochemically characterized. ReLipB was most active at pH 7.5 and 25 °C. It was stable from pH 4.5–9.0. It exhibited broad substrate specificity towards p-nitrophenyl (pNP) esters (C2–C16) and triacylglycerols (C2–C12), showing the highest specific activities towards pNP laurate (231 U/mg) and tricaprylin (1840 U/mg), respectively. In addition, the enzyme displayed excellent stability with high concentrations of organic solvents including cyclohexane, n-hexane, n-heptane, isooctane and petroleum ester and surfactants.Conclusions
A novel cold-active lipase from Rhizomucor endophyticus was identified, expressed at a high level and biochemically characterized. The high yield and unique enzymatic properties make this lipase of some potential for industrial applications.968.
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