Figure 3.

The structure of Qβ bound to MurA. A, structure of Qβ bound to MurA, colored as follows: coat proteins (blue), A₂ (hot pink), gRNA (yellow), and MurA (orange). B, a 90° turn and cutaway view of Qβ shows MurA bound to the maturation protein with same color scheme as in A except in the case of coat proteins (radially colored from light blue to blue) and extra protein density (green). C, the ribbon model of A₂ bound to MurA with uridine diphosphate GlcNAc (UDP-GlcNAc) in the active site (cornflower blue). D, the ribbon model of MurA viewed from the MurA–A₂ interface. The point mutations that render MurA resistant to A₂ are labeled and shown as red stick models. Locations of the catalytic loop and the UDP-GlcNAc are indicated by black arrows. E, ribbon model of A₂ as viewed from the MurA–A₂ interface. The region interacting with MurA, encompassing the N-terminal β-sheet region of residues 30–120, is outlined by a black lasso. The N and C termini are indicated by black arrows. This research was originally published in Proceedings of the National Academy of Sciences of the United States of America. Cui, Z., Gorzelnik, K. V., Chang, J. Y., Langlais, C., Jakana, J., Young, R., and Zhang, J. Proc. Natl. Acad. Sci. U.S.A. Structures of Qβ virions, virus-like particles, and the Qβ-MurA complex reveal internal coat proteins and the mechanism of host lysis. 2017; 114:11697–11702. © United States National Academy of Sciences.