The E (envelope) protein is the smallest structural protein in all coronaviruses andis the only viral structural protein in which no variation has been detected. Weconducted genome sequencing and phylogenetic analyses...The E (envelope) protein is the smallest structural protein in all coronaviruses andis the only viral structural protein in which no variation has been detected. Weconducted genome sequencing and phylogenetic analyses of SARS-CoV. Based ongenome sequencing, we predicted the E protein is a transmembrane (TM) pro-tein characterized by a TM region with strong hydrophobicity and α-helix con-formation. We identified a segment (NH2-_L-Cys-A-Y-Cys-Cys-N_-COOH) in thecarboxyl-terminal region of the E protein that appears to form three disulfide bondswith another segment of corresponding cysteines in the carboxyl-terminus of the S(spike) protein. These bonds point to a possible structural association between theE and S proteins. Our phylogenetic analyses of the E protein sequences in all pub-lished coronaviruses place SARS-CoV in an independent group in Coronaviridaeand suggest a non-human animal origin.展开更多
文摘The E (envelope) protein is the smallest structural protein in all coronaviruses andis the only viral structural protein in which no variation has been detected. Weconducted genome sequencing and phylogenetic analyses of SARS-CoV. Based ongenome sequencing, we predicted the E protein is a transmembrane (TM) pro-tein characterized by a TM region with strong hydrophobicity and α-helix con-formation. We identified a segment (NH2-_L-Cys-A-Y-Cys-Cys-N_-COOH) in thecarboxyl-terminal region of the E protein that appears to form three disulfide bondswith another segment of corresponding cysteines in the carboxyl-terminus of the S(spike) protein. These bonds point to a possible structural association between theE and S proteins. Our phylogenetic analyses of the E protein sequences in all pub-lished coronaviruses place SARS-CoV in an independent group in Coronaviridaeand suggest a non-human animal origin.