TABLE 1.

Cryo-EM image reconstruction data^a

Type of virus particle	No. of micrographs	Defocus (μm)	No. of particles	PFT CCb	Resolution (Å)
NOIPsc	45	1.3-3.1	341	0.288	24
ACIPsd	39	1.2-3.3	720	0.261	24

^aImages were recorded with an FEI Philips CM300 transmission electron microscope at a calibrated magnification of ×47,400. Micrographs were digitized with a Zeiss-PHODIS scanner to yield a sampling corresponding to 2.95 Å between pixels on the specimen.

^bPFT CC is the correlation coefficient (CC) between the model projection and the corresponding raw image after polar Fourier transformation (PFT) (1).

^cWest Nile virus NOIPs were centered and classified as described by Furst et al. (6) but using the program SPIDER (5). The self-common line method (2) was then applied to the class averages to generate an initial model for the subsequent reconstruction of the NOIP data as for the reconstruction of the West Nile virus ACIP data.

^dThe reconstruction of West Nile virus ACIPs was performed with the cryo-EM image reconstruction of dengue virus ACIPs as a starting model by using the PFT procedure (1).