National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
R35GM122510
米国
引用
ジャーナル: Proc Natl Acad Sci U S A / 年: 2020 タイトル: Structures of filamentous viruses infecting hyperthermophilic archaea explain DNA stabilization in extreme environments. 著者: Fengbin Wang / Diana P Baquero / Leticia C Beltran / Zhangli Su / Tomasz Osinski / Weili Zheng / David Prangishvili / Mart Krupovic / Edward H Egelman / 要旨: Living organisms expend metabolic energy to repair and maintain their genomes, while viruses protect their genetic material by completely passive means. We have used cryo-electron microscopy (cryo-EM) ...Living organisms expend metabolic energy to repair and maintain their genomes, while viruses protect their genetic material by completely passive means. We have used cryo-electron microscopy (cryo-EM) to solve the atomic structures of two filamentous double-stranded DNA viruses that infect archaeal hosts living in nearly boiling acid: rod-shaped virus 1 (SSRV1), at 2.8-Å resolution, and filamentous virus (SIFV), at 4.0-Å resolution. The SIFV nucleocapsid is formed by a heterodimer of two homologous proteins and is membrane enveloped, while SSRV1 has a nucleocapsid formed by a homodimer and is not enveloped. In both, the capsid proteins wrap around the DNA and maintain it in an A-form. We suggest that the A-form is due to both a nonspecific desolvation of the DNA by the protein, and a specific coordination of the DNA phosphate groups by positively charged residues. We extend these observations by comparisons with four other archaeal filamentous viruses whose structures we have previously determined, and show that all 10 capsid proteins (from four heterodimers and two homodimers) have obvious structural homology while sequence similarity can be nonexistent. This arises from most capsid residues not being under any strong selective pressure. The inability to detect homology at the sequence level arises from the sampling of viruses in this part of the biosphere being extremely sparse. Comparative structural and genomic analyses suggest that nonenveloped archaeal viruses have evolved from enveloped viruses by shedding the membrane, indicating that this trait may be relatively easily lost during virus evolution.
#241 - 2020年1月 20年の分子を振り返って (Twenty Years of Molecules) 類似性 (2)
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集合体
登録構造単位
7: DNA (301-MER) 8: DNA (301-MER) A: Structural protein B: Structural protein C: Structural protein D: Structural protein E: Structural protein F: Structural protein G: Structural protein H: Structural protein I: Structural protein J: Structural protein K: Structural protein L: Structural protein M: Structural protein N: Structural protein O: Structural protein P: Structural protein Q: Structural protein R: Structural protein S: Structural protein T: Structural protein U: Structural protein V: Structural protein W: Structural protein a: Structural protein b: Structural protein c: Structural protein d: Structural protein e: Structural protein f: Structural protein g: Structural protein h: Structural protein i: Structural protein j: Structural protein k: Structural protein l: Structural protein m: Structural protein n: Structural protein o: Structural protein p: Structural protein q: Structural protein r: Structural protein s: Structural protein t: Structural protein u: Structural protein v: Structural protein w: Structural protein
根拠: microscopy, helical filament was observed by negative staining and Cryo-EM
タイプ
名称
対称操作
数
identity operation
1_555
1
Buried area
370700 Å2
ΔGint
-2578 kcal/mol
Surface area
185600 Å2
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要素
#1: DNA鎖
DNA (301-MER)
分子量: 92878.148 Da / 分子数: 1 / 由来タイプ: 天然 / 由来: (天然) unclassified Rudivirus (ウイルス) Plasmid details: It is rod-like virus purified from a S. solfataricus strain