Asp-N protease is a highly specific endoproteinase used to improve sequence coverage in mass spectrometry protein identification applications.
- Hydrolyses proteins specifically at the amino side of aspartate and cysteic acid residues thus being complementary to tryptic digests
- Better protein characterisation results from overlapping peptides with complementary chromatographic, ionisation and fragmentation properties thereby increasing sequence coverage
- High specific activity of greater than 20000 units/mg protein
- N-terminal arginine cleavage specificity of 90% for a complex protein sample
- Stable since it's provided in a lyophilised format
Applications include improved sequence coverage of protein digests, in-solution digestion of proteins and in-gel digestion of proteins.
MS-grade zinc metalloproteinase derived from a mutant strain of Pseudomonas fragi and requires a trace amount of zinc for activity. Cleaves primarily at the amino side of aspartate and cysteic acid that results from cysteine oxidation. Cleavage can also occur at glutamic acid; however, the rate of cleavage at the glutamyl residue is significantly lower than the rate of cleavage at the aspartic acid residue. Asp-N Protease can efficiently digest protein in 2 to 20 hours at 37 °C and remains active under denaturing conditions, such as 1 M urea, 2 M guanidine·HCl, 0,1% SDS, 2% CHAPS, and 10% acetonitrile, with optimal activity at pH 6 to 8. This lyophilised enzyme has a mass of 27 kDa and is stable for one year when stored at –20 °C.
