Structural basis of severe acute respiratory syndrome coronavirus ADP-ribose-1''-phosphate dephosphorylation by a conserved domain of nsP3.
The crystal structure of a conserved domain of nonstructural protein 3 (nsP3) from severe acute respiratory syndrome coronavirus (SARS-CoV) has been solved by single-wavelength anomalous dispersion to 1.4 A resolution. The structure of this "X" domain, seen in many single-stranded RNA viruses, reveals a three-layered alpha/beta/alpha core with a macro-H2A-like fold. The putative active site is a solvent-exposed cleft that is conserved in its three structural homologs, yeast Ymx7, Archeoglobus fulgidus AF1521, and Er58 from E. coli. Its sequence is similar to yeast YBR022W (also known as Poa1P), a known phosphatase that acts on ADP-ribose-1''-phosphate (Appr-1''-p). The SARS nsP3 domain readily removes the 1'' phosphate group from Appr-1''-p in in vitro assays, confirming its phosphatase activity. Sequence and structure comparison of all known macro-H2A domains combined with available functional data suggests that proteins of this superfamily form an emerging group of nucleotide phosphatases that dephosphorylate Appr-1''-p.
Saikatendu
Kumar Singh
KS
Department of Cell Biology, The Scripps Research Institute, La Jolla, California 92037, USA.
Joseph
Jeremiah S
JS
Subramanian
Vanitha
V
Clayton
Tom
T
Griffith
Mark
M
Moy
Kin
K
Velasquez
Jeffrey
J
Neuman
Benjamin W
BW
Buchmeier
Michael J
MJ
Stevens
Raymond C
RC
Kuhn
Peter
P
D000246:Adenosine Diphosphate Ribose / Q000031:analogs & derivatives* / Q000378:metabolism; D000595:Amino Acid Sequence; D017124:Conserved Sequence / Q000502:physiology*; D008969:Molecular Sequence Data; D010766:Phosphorylation; D017434:Protein Structure, Tertiary / Q000502:physiology; D012324:RNA-Dependent RNA Polymerase / Q000737:chemistry* / Q000502:physiology*; D045473:Severe acute respiratory syndrome-related coronavirus / Q000737:chemistry* / Q000201:enzymology / Q000502:physiology*; D020539:Sequence Analysis, Protein; D013329:Structure-Activity Relationship; D017361:Viral Nonstructural Proteins / Q000737:chemistry* / Q000502:physiology*
C496852:ADP-ribose 1''-phosphate; D017361:Viral Nonstructural Proteins; D000246:Adenosine Diphosphate Ribose; C510959:Nsp3 protein, SARS-CoV; D012324:RNA-Dependent RNA Polymerase