7eea

Publication Abstract from PubMed

Despite previous structural analyses of bacteriophages, quite little is known about the structures and assembly patterns of cyanophages. Using cryo-EM combined with crystallography, we solve the near-atomic-resolution structure of a freshwater short-tailed cyanophage, Pam1, which comprises a 400-A-long tail and an icosahedral capsid of 650 A in diameter. The outer capsid surface is reinforced by trimeric cement proteins with a beta-sandwich fold, which structurally resemble the distal motif of Pam1's tailspike, suggesting its potential role in host recognition. At the portal vertex, the dodecameric portal and connected adaptor, followed by a hexameric needle head, form a DNA ejection channel, which is sealed by a trimeric needle. Moreover, we identify a right-handed rifling pattern that might help DNA to revolve along the wall of the ejection channel. Our study reveals the precise assembly pattern of a cyanophage and lays the foundation to support its practical biotechnological and environmental applications.

Structure and assembly pattern of a freshwater short-tailed cyanophage Pam1.,Zhang JT, Yang F, Du K, Li WF, Chen Y, Jiang YL, Li Q, Zhou CZ Structure. 2022 Feb 3;30(2):240-251.e4. doi: 10.1016/j.str.2021.10.004. Epub 2021, Nov 1. PMID:34727518^[1]

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