ProAlanase is an endoprotease that preferentially cleaves proteins on the C-terminal side of proline and, to a lesser extent, alanine amino acids. Isolated and purified from the fungus Aspergillus niger, ProAlanase is also known as An-PEP or EndoPro. Peptides derived from protein digestion with ProAlanase are suitable for identification and characterization by mass spectrometry.
Digestion with trypsin often provides incomplete sequence coverage or missed identification of post-translational modifications. Like Trypsin, alternative proteases such as Lys-C, Asp-N, Glu-C and Arg-C also cleave at charged residues, introducing bias to regions within proteins that are digested. The newest solution is ProAlanase, which cleaves at unique, non-charged sites in the proteome.
See more data on the application of proalanase to investigations in paleoproteomics, phosphorylation profiling, de-novo sequencing and disulfide bond mapping in the poster "A Proline- and alanine-specific protease is complementary to trypsin in proteomics applications".