1MEC

CONFORMATIONAL VARIABILITY OF A PICORNAVIRUS CAPSID: PH-DEPENDENT STRUCTURAL CHANGES OF MENGO VIRUS RELATED TO ITS HOST RECEPTOR ATTACHMENT SITE AND DISASSEMBLY

Summary for 1MEC

• Entry DOI: 10.2210/pdb1mec/pdb
• Descriptor: MENGO VIRUS COAT PROTEIN (SUBUNIT VP1), MENGO VIRUS COAT PROTEIN (SUBUNIT VP2), PHOSPHATE ION, ... (6 entities in total)
• Functional Keywords: cardio picornavirus coat protein, icosahedral virus, virus
• Biological source: Mengo virus; More
• Cellular location: Protein 2A: Host nucleus . Protein VP2: Virion. Protein VP3: Virion. Protein VP1: Virion. Protein 2B: Host cytoplasmic vesicle membrane ; Peripheral membrane protein ; Cytoplasmic side . Protein 2C: Host cytoplasmic vesicle membrane ; Peripheral membrane protein ; Cytoplasmic side . Protein 3A: Host cytoplasmic vesicle membrane ; Peripheral membrane protein ; Cytoplasmic side . Protein 3B: Virion . Protease 3C: Host cytoplasm . RNA-directed RNA polymerase 3D-POL: Host cytoplasmic vesicle membrane ; Peripheral membrane protein ; Cytoplasmic side : P12296 P12296 P12296 P12296
• Total number of polymer chains: 4
• Total formula weight: 91778.61

Authors

Rossmann, M.G. (deposition date: 1992-01-17, release date: 1994-01-31, Last modification date: 2024-10-23)

Primary citation

Kim, S.,Boege, U.,Krishnaswamy, S.,Minor, I.,Smith, T.J.,Luo, M.,Scraba, D.G.,Rossmann, M.G.
Conformational variability of a picornavirus capsid: pH-dependent structural changes of Mengo virus related to its host receptor attachment site and disassembly.
Virology, 175:176-190, 1990

PubMed Abstract: The structure of Mengo virus had been determined from crystals grown in the presence of 100 mM phosphate buffer at pH 7.4. It is shown that Mengo virus is poorly infectious at the phosphate concentration similar to that in which it was crystallized. Maximal infectivity is achieved at 10 mM phosphate or less in physiological saline. The phosphate effect is ameliorated when the pH is lowered to 4.6. Although it has not been possible to study the crystal structure of the virus at low phosphate concentrations, it is shown that increasing the Cl- concentration at pH 6.2 or decreasing the pH to 4.6 causes substantial conformational changes confined to the "pit," a deep surface depression. These structural changes involve a movement of the "FMDV loop" (GH loop) in VP1, an ordering of the "VP3 loop" (GH loop in VP3) between 3176 and 3182, the displacement of a bound phosphate near the "FMDV loop" (GH loop in VP1), and movement of the carboxy terminus of VP2. The changes in conformation are correlated with the dissociation of the virion into pentamers at pH 6.2 and 150 mM Cl-. The localization of the conformational changes and the correlated role of the phosphate in controlling infectivity support the hypothesis that the "pit" is the receptor attachment site.

PubMed: 2155508
DOI: 10.1016/0042-6822(90)90198-Z

Experimental method

X-RAY DIFFRACTION (3.2 Å)