6l4z

From Proteopedia

Crystal structure of Zika NS2B-NS3 protease with compound 6

Structural highlights

6l4z is a 8 chain structure with sequence from Zika virus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 1.9Å
Ligands:
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

POLG_ZIKV Protein C: Encapsulates the genomic RNA.[UniProtKB:P17763] prM: Acts as a chaperone for envelope protein E during intracellular virion assembly by masking and inactivating envelope protein E fusion peptide. prM is matured in the last step of virion assembly, presumably to avoid catastrophic activation of the viral fusion peptide induced by the acidic pH of the trans-Golgi network. After cleavage by host furin, the pr peptide is released in the extracellular medium and small envelope protein M and envelope protein E homodimers are dissociated.[UniProtKB:P17763] Envelope protein E: Binding to host cell surface receptor is followed by virus internalization through clathrin-mediated endocytosis. Envelope protein E is subsequently involved in membrane fusion between virion and host late endosomes. Synthesized as a homodimer with prM which acts as a chaperone for envelope protein E. After cleavage of prM, envelope protein E dissociate from small envelope protein M and homodimerizes.[UniProtKB:P17763] Non-structural protein 1: Involved in virus replication and regulation of the innate immune response.[UniProtKB:P17763] Non-structural protein 2A: May be involved viral RNA replication and capsid assembly.[UniProtKB:P09732] Non-structural protein 4A: Induces host endoplasmic reticulum membrane rearrangements leading to the formation of virus-induced membranous vesicles hosting the dsRNA and polymerase, functioning as a replication complex. NS4A might also regulate the ATPase activity of the helicase region of Serine protease NS3 chain.[UniProtKB:P17763] Peptide 2k: Functions as a signal peptide for NS4B and is required for the interferon antagonism activity of the latter.[UniProtKB:P17763] Non-structural protein 4B: Inhibits interferon (IFN)-induced host STAT1 phosphorylation and nuclear translocation, thereby preventing the establishment of cellular antiviral state by blocking the IFN-alpha/beta pathway.[UniProtKB:P17763]

Publication Abstract from PubMed

Zika virus (ZIKV) NS2B-NS3 protease is a validated antiviral target as it is essential for maturation of viral proteins. However, its negatively charged active site hinders the development of orthosteric small-molecule inhibitors. Fragment-based drug discovery (FBDD) is a powerful tool to generate novel chemical starting points against difficult drug targets. In this study, we scre ened a fragment compound library against the Zika protease using a primary thermal shift assay and identified twenty-two fragments which (bind to and) stabilize the protease. We then determined the X-ray crystal structures of two hits from different classes, all of which bind to the S1 pocket of the protease. We confirmed that these two fragments bind to the protease without inducing significant conformational changes using solution NMR spectroscopy. These fragment scaffolds serve as the starting point for subsequent lead compound development.

Identification and structural characterization of small molecule fragments targeting Zika virus NS2B-NS3 protease.,Quek JP, Liu S, Zhang Z, Li Y, Ng EY, Loh YR, Hung AW, Luo D, Kang C Antiviral Res. 2020 Mar;175:104707. doi: 10.1016/j.antiviral.2020.104707. Epub , 2020 Jan 15. PMID:31953156^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Quek JP, Liu S, Zhang Z, Li Y, Ng EY, Loh YR, Hung AW, Luo D, Kang C. Identification and structural characterization of small molecule fragments targeting Zika virus NS2B-NS3 protease. Antiviral Res. 2020 Mar;175:104707. PMID:31953156 doi:10.1016/j.antiviral.2020.104707