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排序方式: 共有573条查询结果,搜索用时 156 毫秒
571.
Xing Zhu Dhiraj Mannar Shanti S. Srivastava Alison M. Berezuk Jean-Philippe Demers James W. Saville Karoline Leopold Wei Li Dimiter S. Dimitrov Katharine S. Tuttle Steven Zhou Sagar Chittori Sriram Subramaniam 《PLoS biology》2021,19(4)
The recently reported “UK variant” (B.1.1.7) of SARS-CoV-2 is thought to be more infectious than previously circulating strains as a result of several changes, including the N501Y mutation. We present a 2.9-Å resolution cryo-electron microscopy (cryo-EM) structure of the complex between the ACE2 receptor and N501Y spike protein ectodomains that shows Y501 inserted into a cavity at the binding interface near Y41 of ACE2. This additional interaction provides a structural explanation for the increased ACE2 affinity of the N501Y mutant, and likely contributes to its increased infectivity. However, this mutation does not result in large structural changes, enabling important neutralization epitopes to be retained in the spike receptor binding domain. We confirmed this through biophysical assays and by determining cryo-EM structures of spike protein ectodomains bound to 2 representative potent neutralizing antibody fragments. 相似文献
572.
Booysen Elzaan Bezuidenhout Martin van Staden Anton Du Preez Dimitrov Dimiter Deane Shelly M. Dicks Leon M. T. 《Probiotics and antimicrobial proteins》2019,11(1):310-316
Probiotics and Antimicrobial Proteins - Vancomycin is often used to treat infections caused by β-lactam-resistant bacteria. However, methicillin-resistant strains of Staphylococcus aureus... 相似文献
573.
Dimitrov Ivan Bangov Ivan Flower Darren R. Doytchinova Irini 《Journal of molecular modeling》2014,20(6):1-6
The microcosmic mechanism of the Menshutkin reaction between DABCO and benzyl fluoride/fluorodiphenylmethane has been investigated in both the gas and solvent phase by performing DFT calculations at B3LYP/6-31G(d,p) level of theory. The Gibbs free energy profiles to reach the possible transition states, i.e., five-membered ring transition state and SN2 transition state show that the reaction between DABCO and benzyl fluoride proceeds through SN2 transition state in accordance with previously reported studies, while the reaction between DABCO and fluorodiphenylmethane proceeds through five-membered ring transition state contrary to earlier literature. The role of solvent has been elucidated by reoptimizing the structures using SMD model of solvation. Hydrogen bonding and steric hinderance have been identified as the key factors in guiding the reaction pathway of commercially important Menshutkin reaction. 相似文献