Structural basis for neutralization of an anicteric hepatitis associated echovirus by a potent neutralizing antibody

Atomic Structures of Coxsackievirus B5 Provide Key Information on Viral Evolution and Survival

“…However, no empty particle with a smaller radius was found after several rounds of 3D no-alignment classifications using different batches of particles, which is just like E18, CVB1 ( 13 , 20 ). This is different from what has been found in the cases of E3, E30, E6, and E11, where an empty particle with a similar radius to the compacted F particle could be observed ( 11 , 12 , 15 , 18 , 21 ).…”

“…1c ). Based on what has been observed for Echovirus 30 (E30) and E3 ( 11 , 18 ), the lower band (~143 S) might be the mixture of the F particles and A particles, which could not be distinctively separated out probably because of their similar molecular weights and mutual viscosity. The sample containing a mixture of viral particles was vitrified on a cryo-EM grid and loaded onto a 300-kV Titan Krios for data collection.…”

“…While the slender VP4 resided on the interior of the capsid shell, sneaking from the 5-fold axis to 3-fold axis, resembling all the other 10 structure-known EV-Bs including E1, E3, E6, E7, E11, E18, E30, CVB1, CVB3, and CVA9 ( Fig. 2d ) ( 11 – 13 , 15 , 18 , 20 , 21 , 24 – 26 ), the other three viral proteins (VP1-3), which all contained the well-conserved eight-stranded anti-parallel β-barrel motifs, altogether constituted the outer surface of the capsid with their N termini located inside and C termini extended outward. Interestingly, most of the loops connecting the β sheets were exposed on the exterior of the surface and have been suggested to be involved in antibody and receptor binding for EV-Bs ( Fig.…”

“…Interestingly, most of the loops connecting the β sheets were exposed on the exterior of the surface and have been suggested to be involved in antibody and receptor binding for EV-Bs ( Fig. 2c ) ( 11 , 18 , 19 , 23 ).…”

“…The procapsids are further matured by RNA packing followed by VP0 cleavage into VP2 and VP4, priming for the viral release through membrane fusion ( 11 – 17 ). During the life cycle, the viral capsid undergoes uncoating and maturation, serving as the direct targets for cell receptors and neutralizing MAbs ( 18 , 19 ). Therefore, a detailed study of the capsid could aid in the understanding of viral cell entry, viral antigenicity, and pathogenesis, thus facilitating the development of antiviral vaccines and agents.…”