The importance of the Q motif in the ATPase activity of a viral helicase

FEBS Letters

Gallivan, J.-P¹  McGarvey, Michael J¹ 

[1] Department of Medicine, Faculty of Medicine, Imperial College London, St Mary's Hospital Campus, London W2 1NY, UK

关键词: NS3;    DExD/H box helicase;    Q motif;   

DOI  :  10.1016/S0014-5793(03)01229-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

NS3 proteins of flaviviruses contain motifs which indicate that they possess protease and helicase activities. The helicases are members of the DExD/H box helicase superfamily and NS3 proteins from some flaviviruses have been shown to possess ATPase and helicase activities in vitro. The Q motif is a recently recognised cluster of nine amino acids common to most DExD/H box helicases which is proposed to regulate ATP binding and hydrolysis. In addition a conserved residue occurs 17 amino acids upstream of the Q motif (‘+17’). We have analysed full-length and truncated NS3 proteins from Powassan virus (a tick-borne flavivirus) to investigate the role that the Q motif plays in the hydrolysis of ATP by a viral helicase. The Q motif appears to be essential for the activity of Powassan virus NS3 ATPase, however NS3 deletion mutants that contain the Q motif but lack the ‘+17’ amino acid have ATPase activity albeit at a reduced level.

【 授权许可】

Unknown