3ja7

Publication Abstract from PubMed

The structure and assembly of bacteriophage T4 has been extensively studied. However, the detailed structure of the portal protein remained unknown. Here we report the structure of the bacteriophage T4 portal assembly, gene product 20 (gp20), determined by cryo-electron microscopy (cryo-EM) to 3.6 A resolution. In addition, analysis of a 10 A resolution cryo-EM map of an empty prolate T4 head shows how the dodecameric portal assembly interacts with the capsid protein gp23 at the special pentameric vertex. The gp20 structure also verifies that the portal assembly is required for initiating head assembly, for attachment of the packaging motor, and for participation in DNA packaging. Comparison of the Myoviridae T4 portal structure with the known portal structures of phi29, SPP1 and P22, representing Podo- and Siphoviridae, shows that the portal structure probably dates back to a time when self-replicating microorganisms were being established on Earth.

Cryo-EM structure of the bacteriophage T4 portal protein assembly at near-atomic resolution.,Sun L, Zhang X, Gao S, Rao PA, Padilla-Sanchez V, Chen Z, Sun S, Xiang Y, Subramaniam S, Rao VB, Rossmann MG Nat Commun. 2015 Jul 6;6:7548. doi: 10.1038/ncomms8548. PMID:26144253^[3]

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