This is the nucleic acid-binding domain (NAB) from the multidomain nonstructural protein NSP3, and described as NSP3e domain. NSP3 is part of Orf1a polyproteins in SARS-CoV [1]. It is an essential component of the replication/transcription complex [2 ...
This is the nucleic acid-binding domain (NAB) from the multidomain nonstructural protein NSP3, and described as NSP3e domain. NSP3 is part of Orf1a polyproteins in SARS-CoV [1]. It is an essential component of the replication/transcription complex [2]. The global domain of the NAB represents a new fold, with a parallel four-strand beta-sheet holding two alpha-helices of three and four turns that are oriented antiparallel to the beta-strands and a group of residues form a positively charged patch on the protein surface as the binding site responsible for binding affinity for nucleic acids. When binding to ssRNA, the NAB prefers sequences with repeats of three consecutive Gs, such as (GGGA)5 and (GGGA)2. A positively charged surface patch (Lys75, Lys76, Lys99, and Arg106) is involved in RNA binding [2,3,4].
