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5hx2
From Proteopedia
In vitro assembled star-shaped hubless T4 baseplate
Structural highlights
Function[BP53_BPT4] Baseplate protein that is part of the baseplate wedge (PubMed:15315755). Involved in the tail assembly.[1] [2] [BP07_BPT4] Baseplate protein that is part of the baseplate wedge. Involved in the tail assembly.[3] [4] [BP06_BPT4] Baseplate protein that is part of the baseplate wedge (PubMed:15315755). Involved in the tail assembly.[5] [6] [BP08_BPT4] Baseplate protein that is part of the baseplate wedge. Involved in the tail assembly.[7] [8] [BP10_BPT4] Baseplate protein that is part of the baseplate wedge and that connects the short tail fibers to the baseplate (PubMed:16554069). During infection, the baseplate undergoes a conformational change from a dome-shaped to a star-shaped structure. At this point, gp10 rotates and acts as a lever that unfolds the short tail fibers, which then interact with host cell surface receptors. Involved in the tail assembly.[9] [10] Publication Abstract from PubMedBacteriophage T4 consists of a head for protecting its genome and a sheathed tail for inserting its genome into a host. The tail terminates with a multiprotein baseplate that changes its conformation from a "high-energy" dome-shaped to a "low-energy" star-shaped structure during infection. Although these two structures represent different minima in the total energy landscape of the baseplate assembly, as the dome-shaped structure readily changes to the star-shaped structure when the virus infects a host bacterium, the dome-shaped structure must have more energy than the star-shaped structure. Here we describe the electron microscopy structure of a 3.3-MDa in vitro-assembled star-shaped baseplate with a resolution of 3.8 A. This structure, together with other genetic and structural data, shows why the high-energy baseplate is formed in the presence of the central hub and how the baseplate changes to the low-energy structure, via two steps during infection. Thus, the presence of the central hub is required to initiate the assembly of metastable, high-energy structures. If the high-energy structure is formed and stabilized faster than the low-energy structure, there will be insufficient components to assemble the low-energy structure. Role of bacteriophage T4 baseplate in regulating assembly and infection.,Yap ML, Klose T, Arisaka F, Speir JA, Veesler D, Fokine A, Rossmann MG Proc Natl Acad Sci U S A. 2016 Mar 8;113(10):2654-9. doi:, 10.1073/pnas.1601654113. Epub 2016 Feb 29. PMID:26929357[11] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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Categories: Fokine, A | Klose, T | Rossmann, M G | Yap, M L | Baseplate | Complex | T4 | Viral protein
