|PROSITE documentation PDOC00865 [for PROSITE entry PS50830]|
Staphylococcus aureus secretes a thermostable nuclease (EC 22.214.171.124), known as thermonuclease (TNase) or staphylococcal nuclease (SNase), which is a calcium-dependent enzyme that catalyzes the hydrolysis of both DNA and RNA at the 5' position of the phosphodiester bond yielding 3'-mononucleotides and dinucleotides . Three residues, two arginines and a glutamate, have been implicated in the catalytic mechanism.
- Nuclease from the pSa plasmid of Shigella flexneri. - Escherichia coli plasmid RP4 parB protein, which is involved in plasmid partition. - Escherichia coli plasmid R100 hypothetical protein (OrfA). - Rhizobium meliloti succinoglycan biosynthesis protein exoI. - Bacillus subtilis hypothetical protein yhcR. - Mycoplasma genitalium hypothetical lipoprotein MG186. - Haemophilus influenzae hypothetical protein HI1296. - Methanococcus jannaschii hypothetical protein MJ1439. - Yeast hypothetical protein Ygl085w. - A 38.1 Kd protein of unknown function from the plant Corydalis sempervirens. - Human Epstein-Barr virus nuclear antigen 2 (EBNA-2) coactivator p100, which contains four repeats homologous to TNase. As each of these repeats lacks equivalent TNase catalytic residues, they are unlikely to possess TNase-like activities, but may mediate single-stranded DNA-binding function. - Caenorhabditis elegans F10g7.2 protein, which is similar to the human p100 coactivator.
The TNase-like domain is about 150 residues long and consists of a highly twisted five stranded β-barrel and three helices. It folds into two subdomains consisting of an oligonucleotide/oligosaccharide-binding (OB)-fold and two C-terminal helices. The OB-fold consists of a five-stranded Greek-key β-barrel often capped by an α-helix located between the third and fourth strands. It is found in several proteins that bind nucleic acid as well as carbohydrates, whereas others bind protein receptors or small molecules .
We developed two signature patterns based on conserved regions that each contain active site residues. We also developed a profile that spans the entire TNase-like domain.Last update:
April 2006 / Pattern revised.
PROSITE methods (with tools and information) covered by this documentation:
|1||Authors||Hynes T.R. Fox R.O.|
|Title||The crystal structure of staphylococcal nuclease refined at 1.7 A resolution.|
|2||Authors||Chesneau O. el Solh N.|
|Title||Primary structure and biological features of a thermostable nuclease isolated from Staphylococcus hyicus.|
|Title||P100, a transcriptional coactivator, is a human homologue of staphylococcal nuclease.|
|Source||Protein Sci. 6:459-463(1997).|
|4||Authors||Callebaut I. Mornon J.-P.|
|Title||The human EBNA-2 coactivator p100: multidomain organization and relationship to the staphylococcal nuclease fold and to the tudor protein involved in Drosophila melanogaster development.|
|Source||Biochem. J. 321:125-132(1997).|