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31.
Inhibitor design by wrapping packing defects in HIV-1 proteins 总被引:1,自引:0,他引:1
Fernández A Rogale K Scott R Scheraga HA 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(32):11640-11645
Two viral proteins, HIV-1 protease and HIV-1 integrase, have been targeted for inhibitor design to prevent assembly and maturation of HIV-1 virions. The enzymatic mechanism of these proteins involves side-chain groups that serve as general acids or bases. Furthermore, catalytic activity requires that water be removed from the microenvironment surrounding the chemical reaction site or be constrained to serve as an activated nucleophile. Here, we identify previously unrecognized structural features that promote water removal from polar catalytic regions. Packing defects in the form of hydrogen bonds that are insufficiently dehydrated intramolecularly, named "dehydrons," are strategically placed in the structure to induce an anhydrous enzymatic pathway. Dehydrons become electrostatically enhanced and stabilized upon further desolvation. Thus, packing defects act synergistically with the polar active groups to enhance the enzymatic electrostatics. However, because dehydrons are sticky, they constitute targets for inhibitor design. We noticed that inhibitors attach to polar surfaces by further desolvating dehydrons, thus blocking the active sites or the sites involved in harnessing the substrate. The dehydrons are thus required for functional reasons, making them suitable targets. The differences in success when targeting HIV-1 protease, feline immunodeficiency virus protease, and HIV-1 integrase are rationalized in terms of the dehydron distribution, revealing possible improvements in the targeting strategy. Principles of design optimization are proposed to create an inhibitor that can be neutralized only at the expense of the loss of catalytic function. The possibility of using drugs that wrap dehydrons to block protein-protein associations is also discussed. 相似文献
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Vitamin D Analogue: Potent Antiproliferative Effects on Cancer Cell Lines and Lack of Hypercalcemic Activity 下载免费PDF全文
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Amirahmadi Roxana Sullivan Scott Britton Noel Siegel Ariel Spiegel Rory Miceli Jennifer Duong Vu Sholander Jeffrey T. Fontaine Magali J. McCurdy Michael T. 《Annals of hematology》2022,101(9):2045-2052
Annals of Hematology - Despite the low risk of peripherally inserted central catheter (PICC) insertion-related bleeding, the practice of administering prophylactic platelets varies greatly.... 相似文献
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Folayan Morenike Oluwatoyin Ibigbami Olanrewaju Brown Brandon El Tantawi Maha Uzochukwu Benjamin Ezechi Oliver C. Aly Nourhan M. Abeldaño Giuliana Florencia Ara Eshrat Ayanore Martin Amogre Ayoola Oluwagbemiga O. Osamika Bamidele Emmanuel Ellakany Passent Gaffar Balgis Idigbe Ifeoma Ishabiyi Anthonia Omotola Jafer Mohammed Khan Abeedha Tu-Allah Khalid Zumama Lawal Folake Barakat Lusher Joanne Nzimande Ntombifuthi P. Popoola Bamidele Olubukola Quadri Mir Faeq Ali Rashwan Maher Roque Mark Shamala Anas Al-Tammemi Ala’a B. Yousaf Muhammad Abrar Abeldaño Zuñiga Roberto Ariel Okeibunor Joseph Chukwudi Nguyen Annie Lu 《AIDS and behavior》2022,26(3):739-751
AIDS and Behavior - The aim of the study was to assess if there were significant differences in the adoption of COVID-19 risk preventive behaviors and experience of food insecurity by people living... 相似文献