7YFW

Cyanophage Pam3 fiber

Summary for 7YFW

• Entry DOI: 10.2210/pdb7yfw/pdb
• EMDB information: 33799
• Descriptor: Pam3 fiber proreins (1 entity in total)
• Functional Keywords: fiber, virus, viral protein
• Biological source: uncultured cyanophage
• Total number of polymer chains: 3
• Total formula weight: 81971.37

Authors

Yang, F.,Jiang, Y.L.,Zhou, C.Z. (deposition date: 2022-07-09, release date: 2023-01-18, Last modification date: 2024-07-03)

Primary citation

Yang, F.,Jiang, Y.L.,Zhang, J.T.,Zhu, J.,Du, K.,Yu, R.C.,Wei, Z.L.,Kong, W.W.,Cui, N.,Li, W.F.,Chen, Y.,Li, Q.,Zhou, C.Z.
Fine structure and assembly pattern of a minimal myophage Pam3.
Proc.Natl.Acad.Sci.USA, 120:e2213727120-e2213727120, 2023

PubMed Abstract: The myophage possesses a contractile tail that penetrates its host cell envelope. Except for investigations on the bacteriophage T4 with a rather complicated structure, the assembly pattern and tail contraction mechanism of myophage remain largely unknown. Here, we present the fine structure of a freshwater cyanophage Pam3, which has an icosahedral capsid of ~680 Å in diameter, connected via a three-section neck to an 840-Å-long contractile tail, ending with a three-module baseplate composed of only six protein components. This simplified baseplate consists of a central hub-spike surrounded by six wedge heterotriplexes, to which twelve tail fibers are covalently attached via disulfide bonds in alternating upward and downward configurations. In vitro reduction assays revealed a putative redox-dependent mechanism of baseplate assembly and tail sheath contraction. These findings establish a minimal myophage that might become a user-friendly chassis phage in synthetic biology.

PubMed: 36656854
DOI: 10.1073/pnas.2213727120

Experimental method

ELECTRON MICROSCOPY (3.96 Å)