6d0u

From Proteopedia

Crystal structure of C05 V110P/A117E mutant bound to H3 influenza hemagglutinin, HA1 subunit

Structural highlights

6d0u is a 12 chain structure with sequence from Homo sapiens and Influenza A virus (A/Hong Kong/1/1968(H3N2)). Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 3.25Å
Ligands:
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

HEMA_I68A4 Binds to sialic acid-containing receptors on the cell surface, bringing about the attachment of the virus particle to the cell. This attachment induces virion internalization of about two third of the virus particles through clathrin-dependent endocytosis and about one third through a clathrin- and caveolin-independent pathway. Plays a major role in the determination of host range restriction and virulence. Class I viral fusion protein. Responsible for penetration of the virus into the cell cytoplasm by mediating the fusion of the membrane of the endocytosed virus particle with the endosomal membrane. Low pH in endosomes induces an irreversible conformational change in HA2, releasing the fusion hydrophobic peptide. Several trimers are required to form a competent fusion pore (By similarity).

Publication Abstract from PubMed

Influenza is a yearly threat to global public health. Rapid changes in influenza surface proteins resulting from antigenic drift and shift events make it difficult to readily identify antibodies with broadly neutralizing activity against different influenza subtypes with high frequency, specifically antibodies targeting the receptor binding domain (RBD) on influenza HA protein. We developed an optimized computational design method that is able to optimize an antibody for recognition of large panels of antigens. To demonstrate the utility of this multistate design method, we used it to redesign an antiinfluenza antibody against a large panel of more than 500 seasonal HA antigens of the H1 subtype. As a proof of concept, we tested this method on a variety of known antiinfluenza antibodies and identified those that could be improved computationally. We generated redesigned variants of antibody C05 to the HA RBD and experimentally characterized variants that exhibited improved breadth and affinity against our panel. C05 mutants exhibited improved affinity for three of the subtypes used in design by stabilizing the CDRH3 loop and creating favorable electrostatic interactions with the antigen. These mutants possess increased breadth and affinity of binding while maintaining high-affinity binding to existing targets, surpassing a major limitation up to this point.

Multistate design of influenza antibodies improves affinity and breadth against seasonal viruses.,Sevy AM, Wu NC, Gilchuk IM, Parrish EH, Burger S, Yousif D, Nagel MBM, Schey KL, Wilson IA, Crowe JE Jr, Meiler J Proc Natl Acad Sci U S A. 2019 Jan 14. pii: 1806004116. doi:, 10.1073/pnas.1806004116. PMID:30642961^[1]

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

References

↑ Sevy AM, Wu NC, Gilchuk IM, Parrish EH, Burger S, Yousif D, Nagel MBM, Schey KL, Wilson IA, Crowe JE Jr, Meiler J. Multistate design of influenza antibodies improves affinity and breadth against seasonal viruses. Proc Natl Acad Sci U S A. 2019 Jan 14. pii: 1806004116. doi:, 10.1073/pnas.1806004116. PMID:30642961 doi:http://dx.doi.org/10.1073/pnas.1806004116