Structural characterization of the E2 glycoprotein from Sindbis by lysine biotinylation and LC-MS/MS.
Sindbis is an Alphavirus capable of infecting and replicating in both vertebrate and invertebrate hosts. Mature Sindbis virus particles consist of an inner capsid surrounded by a host-derived lipid bilayer, which in turn is surrounded by a protein shell consisting of the E1 and E2 glycoproteins. While a homolog of the E1 glycoprotein has been structurally characterized, the amount of structural data on the E2 glycoprotein is considerably less. In this study, the organization of the E2 glycoprotein was probed by surface biotinylation of intact virions. The virus remained fully infectious, demonstrating that the biotinylation did not alter the topology of the proteins involved in infection. Seven sites of modification were identified in the E2 glycoprotein (K70, K76, K97, K131, K149, K202, and K235), while one site of modification in the E1 glycoprotein (K16) was identified, confirming that the E1 protein is almost completely buried in the virus structure.
Sharp
Joshua S
JS
Laboratory of Structural Biology, National Institute of Environmental Health Sciences, 111 T.W. Alexander Dr., P.O. Box 12233, MD F0-04, Research Triangle Park, NC 27709, USA. sharp1@niehs.nih.gov
Nelson
Steevenson
S
Brown
Dennis
D
Tomer
Kenneth B
KB
D000595:Amino Acid Sequence; D000818:Animals; D001710:Biotin / Q000378:metabolism*; D002460:Cell Line; D006224:Cricetinae; D008239:Lysine / Q000378:metabolism; D013058:Mass Spectrometry / Q000379:methods*; D046529:Microscopy, Electron, Transmission; D008969:Molecular Sequence Data; D020836:Protein Structure, Quaternary; D012845:Sindbis Virus / Q000737:chemistry* / Q000502:physiology / Q000648:ultrastructure; D013194:Staining and Labeling / Q000379:methods*; D014759:Viral Envelope Proteins / Q000737:chemistry* / Q000648:ultrastructure*; D010948:Viral Plaque Assay; D014771:Virion / Q000737:chemistry / Q000648:ultrastructure
D014759:Viral Envelope Proteins; C064950:glycoprotein E2, Sindbis virus; D001710:Biotin; D008239:Lysine