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正Dear Editor,Till January 20, 2020, the 2019-new coronavirus(2019-nCoV) has caused more than one hundred cases in Wuhan(WMHC 2020). During a retrospective study of recent pneumonia patients in our department, we found two patients who are likely being infected with the 2019-nCoV. 相似文献
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Lu Ligong Zhang Hui Zhan Meixiao Jiang Jun Yin Hua Dauphars Danielle J. Li Shi-You Li Yong He You-Wen 《中国科学:生命科学英文版》2020,63(12):1833-1849
Science China Life Sciences - The newly emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected millions of people and caused tremendous morbidity and mortality worldwide.... 相似文献
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Sufang Zhang Sifan Shen Jiong Peng Xin Zhou Xiangbo Kong Pingping Ren Fu Liu Lingling Han Shuai Zhan Yongping Huang Aibing Zhang Zhen Zhang 《Molecular ecology resources》2020,20(4):1023-1037
Dendrolimus spp. are important destructive pests of conifer forests, and Dendrolimus punctatus Walker (Lepidoptera; Lasiocampidae) is the most widely distributed Dendrolimus species. During periodic outbreaks, this species is said to make “fire without smoke” because large areas of pine forest can be quickly and heavily damaged. Yet, little is known about the molecular mechanisms that underlie the unique ecological characteristics of this forest insect. Here, we combined Pacific Biosciences (PacBio) RSII single‐molecule long reads and high‐throughput chromosome conformation capture (Hi‐C) genomics‐linked reads to produce a high‐quality, chromosome‐level reference genome for D. punctatus. The final assembly was 614 Mb with contig and scaffold N50 values of 1.39 and 22.15 Mb, respectively, and 96.96% of the contigs anchored onto 30 chromosomes. Based on the prediction, this genome contained 17,593 protein‐coding genes and 56.16% repetitive sequences. Phylogenetic analyses indicated that D. punctatus diverged from the common ancestor of Hyphantria cunea, Spodoptera litura and Thaumetopoea pityocampa ~ 108.91 million years ago. Many gene families that were expanded in the D. punctatus genome were significantly enriched for the xenobiotic biodegradation system, especially the cytochrome P450 gene family. This high‐quality, chromosome‐level reference genome will be a valuable resource for understanding mechanisms of D. punctatus outbreak and host resistance adaption. Because this is the first Lasiocampidae insect genome to be sequenced, it also will serve as a reference for further comparative genomics. 相似文献
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具有多重耐药性和广泛耐药性的结核分枝杆菌菌株正在全球范围内传播,因此,迫切需要新的抗结核药物。结核分枝杆菌的L,D-转肽酶LdtMt2直接参与肽聚糖的形成,细菌毒性和β-内酰胺抗性。该酶是潜在的抗结核靶标,可以被碳青霉烯类抗生素抑制,碳青霉烯类抗生素是FDA批准的用于治疗肺结核的药物。据报道,LdtMt2与碳青霉烯类抗生素(如厄他培南,亚胺培南和美洛培南)相互作用时,存在两种不同的中间状态,即状态I和II。状态I被认为是初始加合物形成状态,而状态II被认为是稳定的蛋白质-配体相互作用状态,并伴有碳青霉烯类抗生素和蛋白质的局部构象排列。本文中,我们报告了一个LdMt2-ertapenem新中间状态I-plus,具有与状态II相同的碳青霉烯类抗生素构象和与状态I相似的局部蛋白质构象。该新状态是从状态I转变为状态II的中间状态,构象变化发生在厄他培南分子而不是蛋白质。我们的工作有助于阐明碳青霉烯类抗生素对LdtMt2的作用后发生的变化,并与其他报道的中间状态一起揭示L,D-转肽酶如何与碳青霉烯类抗生素相互作用。 相似文献
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Joe Carver Domingos Ng Michelle Zhou Peggy Ko Dejin Zhan Mandy Yim David Shaw Brad Snedecor Michael W. Laird Steven Lang Amy Shen Zhilan Hu 《Biotechnology progress》2020,36(4):e2967
Historically, therapeutic protein production in Chinese hamster ovary (CHO) cells has been accomplished by random integration (RI) of expression plasmids into the host cell genome. More recently, the development of targeted integration (TI) host cells has allowed for recombination of plasmid DNA into a predetermined genomic locus, eliminating one contributor to clone-to-clone variability. In this study, a TI host capable of simultaneously integrating two plasmids at the same genomic site was used to assess the effect of antibody heavy chain and light chain gene dosage on antibody productivity. Our results showed that increasing antibody gene copy number can increase specific productivity, but with diminishing returns as more antibody genes are added to the same TI locus. Random integration of additional antibody DNA copies in to a targeted integration cell line showed a further increase in specific productivity, suggesting that targeting additional genomic sites for gene integration may be beneficial. Additionally, the position of antibody genes in the two plasmids was observed to have a strong effect on antibody expression level. These findings shed light on vector design to maximize production of conventional antibodies or tune expression for proper assembly of complex or bispecific antibodies in a TI system. 相似文献
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Molecular Biology Reports - Chemosensory receptors in the dendritic membrane of olfactory cells are critical for the molecular recognition and discrimination of odorants. Tropidothorax elegans is a... 相似文献