对乙型肝炎病毒衣壳组装的苯甲酰胺衍生物的发现和研究

newchinabok

Discovery and mechanistic study of benzamide derivatives that modulate hepatitis B virus capsid assembly
Shuo Wu1, Qiong Zhao1, Pinghu Zhang1,2, John Kulp1, Lydia Hu1, Nicky Hwang1, Jiming Zhang3, Timothy M. Block1, Xiaodong Xu1, Yanming Du1, Jinhong Chang1 and Ju-Tao Guo1*
+ Author Affiliations
1Baruch S. Blumberg Institute, Hepatitis B Foundation, 3805 Old Easton Road, Doylestown, Pennsylvania, USA.
2Jiangsu Key Laboratory of New Drug Screening & Jiangsu Center for Pharmacodynamics Research and Evaluation & State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu Province, China.
3Department of Infectious Diseases, Huashan Hospital, Fudan University, 12 Wulumuqi Middle Road, Shanghai, China.
ABSTRACT
Chronic hepatitis B virus (HBV) infection is a global public health problem. Although the currently approved medications can reliably reduce the viral load and prevent the progression of liver diseases, they fail to cure the viral infection. In an effort toward discovery of novel antiviral agents against HBV, a group of benzamide (BA) derivatives that significantly reduced the amount of cytoplasmic HBV DNA were discovered. The initial lead optimization efforts identified two BA derivatives with improved antiviral activity for further mechanistic studies. Interestingly, similar to our previously reported sulfamoylbenzamides (SBAs), the BAs promote the formation of empty capsids through specific interaction with HBV core protein, but not other viral and host cellular components. Genetic evidence suggested that both SBAs and BAs inhibited HBV nucleocapsid assembly by binding to the “HAP” pocket between core protein dimer-dimer interfaces. However, unlike SBAs, BA compounds uniquely induced the formation of empty capsids that migrated slower in native agarose gel electrophoresis from A36V mutant core protein. Moreover, we showed that assembly of chimeric capsids from wild-type and drug-resistant core proteins was susceptible to multiple capsid assembly modulators. Hence HBV core protein is a dominant antiviral target that may suppress the selection of drug resistant viruses during core protein-targeting antiviral therapy. Our studies thus indicate that BAs are a chemically and mechanistically unique type of HBV capsid assembly modulators and warranted for further development as antiviral agents against HBV.
IMPORTANCE HBV core protein plays essential roles in many steps of viral replication cycle. In addition to packaging viral pregenomic (pg) RNA and DNA polymerase complex into nucleocapsids for reverse transcriptional DNA replication to take place, the core protein dimers, existing in several different quaternary structures in infected hepatocytes, participate in and regulate HBV virion assembly, capsid uncoating and cccDNA formation. It is anticipated that small molecular core protein assembly modulators may disrupt one or multiple steps of HBV replication, depending on their interaction with the distinct quaternary structures of core protein. Discovery of novel core protein-targeting antivirals, such as benzamide derivatives reported herein, and investigation of their antiviral mechanism may lead to the identification of antiviral therapeutics for the cure of chronic hepatitis B.

newchinabok

abus科研人员写的

newchinabok

http://jvi.asm.org/content/early ... 1-9e82-298847e7f54f

newchinabok

我发的链接大家能不能打开？

newchinabok

Hepatitis B Virus Capsids Have Diverse Structural Responses to Small-Molecule Ligands Bound to the Heteroaryldihydropyrimidine Pocket
Balasubramanian Venkatakrishnana, Sarah P. Katenb, Samson Francisa,b, Srinivas Chirapuc,d, M. G. Finnc,d and Adam Zlotnicka
aMolecular and Cellular Biochemistry Department, Indiana University, Bloomington, Indiana, USA
bAssembly Biosciences, Bloomington, Indiana, USA, and San Francisco, California, USA
cDepartment of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California, USA
dGeorgia Institute of Technology, School of Chemistry and Biochemistry, Atlanta, Georgia, USA
W. I. Sundquist, Editor
+ Author Affiliations
ABSTRACT
Though the hepatitis B virus (HBV) core protein is an important participant in many aspects of the viral life cycle, its best-characterized activity is self-assembly into 240-monomer capsids. Small molecules that target core protein (core protein allosteric modulators [CpAMs]) represent a promising antiviral strategy. To better understand the structural basis of the CpAM mechanism, we determined the crystal structure of the HBV capsid in complex with HAP18. HAP18 accelerates assembly, increases protein-protein association more than 100-fold, and induces assembly of nonicosahedral macrostructures. In a preformed capsid, HAP18 is found at quasiequivalent subunit-subunit interfaces. In a detailed comparison to the two other extant CpAM structures, we find that the HAP18-capsid structure presents a paradox. Whereas the two other structures expanded the capsid diameter by up to 10 Å, HAP18 caused only minor changes in quaternary structure and actually decreased the capsid diameter by ∼3 Å. These results indicate that CpAMs do not have a single allosteric effect on capsid structure. We suggest that HBV capsids present an ensemble of states that can be trapped by CpAMs, indicating a more complex basis for antiviral drug design.
IMPORTANCE Hepatitis B virus core protein has multiple roles in the viral life cycle—assembly, compartment for reverse transcription, intracellular trafficking, and nuclear functions—making it an attractive antiviral target. Core protein allosteric modulators (CpAMs) are an experimental class of antivirals that bind core protein. The most recognized CpAM activity is that they accelerate core protein assembly and strengthen interactions between subunits. In this study, we observe that the CpAM-binding pocket has multiple conformations. We compare structures of capsids cocrystallized with different CpAMs and find that they also affect quaternary structure in different ways. These results suggest that the capsid “breathes” and is trapped in different states by the drug and crystallization. Understanding that the capsid is a moving target will aid drug design and improve our understanding of HBV interaction with its environment.

newchinabok

核衣壳抑制从某种意义上就是cccdna抑制剂，间接抑制

咬牙硬挺

感谢分享

newchinabok

回复 咬牙硬挺 的帖子

我的链接打不打的开？

MP4

newchinabok 发表于 2017-6-6 22:02
回复 咬牙硬挺 的帖子

我的链接打不打的开？

你能打开的就不用问别人，打不开也是别人的问题

newchinabok

回复 MP4 的帖子

你的链接和sw链接我都打得开。我的链接打不开，该不会是连到火星去了吧，我要查查，哈哈